DRC-2012-001831 - 0901a06880304e1c

0 ^ - c u 12-001831
Energy FUEIS RESOurces (U5FII Inc.
August 31, 2012
Sent VIA OVERNIGHT DELIVERY
Mr Rusty Lundberg
Division of Radiation Control
Utah Department ofEnvironmental Quality
195 North 1950 West
PO Box 144850
Salt Lake City, UT 84114-4820
Re: Re-transmittal of Responses to Reclamation Plan Interrogatories - Round 1 for Reclamation
Plan, Revision 5.0, March 2012
Dear Mr Lundberg
Mr John Hultquist advised Energy Fuels Resources (USA) Inc ("EFR") that the Utah Division of Radiation
Control ("DRC") did not receive the hard copy and CD ROM of the Responses to Reclamation Plan
Interrogatories - Round 1 for Reclamation Plan, Revision 5 0, which was transmitted from EFR's consultant
MWH Americas, Inc on August 15, 2012 EFR is transmitting, by this letter, one additional hard copy and one
CD ROM of the above-named document MWH Americas is also transmitting to DRC, by Federal Express,
two additional CD ROM copies
Ifyou should have any questions regarding this report please contact me
Yours very truly,
ENERGY FUELS RESOURCES (USA) INC
Jo Ann Tischler
Director, Compliance
CC David C Frydenlund
Harold R Roberts
David E Turk
Kathenne A Weinel
Central Files
Energy Fuels Resources (USA) Inc
Lakewood, CO 80228
225 Union Boulevard, Suite 600
Phone [phone]

ENERGY FUELS RESOURCES (USA) INC.

RESPONSES TO INTERROGATORIES –
ROUND 1 FOR RECLAMATION PLAN,
REVISION 5.0, MARCH 2012;

AUGUST 15, 2012

August 15, 2012
TABLE OF CONTENTS
INTERROGATORY WHITEMESA RECPLAN REV 5.0; R313-24-4; 10CFR40.31(H); INT 01/1:
RESPONSES TO RECLAMATION PLAN REV. 4.0 INTERROGATORIES ........................................... 1 
INTERROGATORY WHITEMESA RECPLAN REV 5.0; R313-24-4; 10CFR40, APPENDIX A,
CRITERION 4; INT 02/1: ENGINEERING DRAWINGS .......................................................................... 3 
INTERROGATORY WHITEMESA RECPLAN Rev. 5.0; R313-24-4; 10CFR40 APPENDIX A
CRITERIA 1 AND 4; INT 03/1: CONSTRUCTION QUALITY ASSURANCE/QUALITY CONTROL
PLAN, COVER CONSTRUCTABILITY, AND FILTER AND ROCK RIP RAP LAYER CRITERIA
AND PLACEMENT ..................................................................................................................................... 7 
INTERROGATORY WHITEMESA RECPLAN Rev5.0; R313-24-4; 10CFR40, APPENDIX A,
CRITERION 4; INT 04/1: VOID SPACE CRITERIA AND DEBRIS, RUBBLE PLACEMENT AND
SOIL/BACKFILL REQUIREMENTS ....................................................................................................... 12 
INTERROGATORY WHITEMESA RECPLAN Rev. 5.0 R313-24-4, 10 CFR 40 APPENDIX A; INT
05/1: SEISMIC HAZARD EVALUATION .............................................................................................. 21 
INTERROGATORY WHITEMESA RECPLAN REV5.0; R313-24-4; 10CFR40 APPENDIX A,
CRITERION 1; INT 06/1: SLOPE STABILITY ........................................................................................ 26 
INTERROGATORY WHITEMESA RECPLAN Rev. 5.0; R313-24-4; 10 CFR 40 APPENDIX A,
CRITERION 4; INT 07/1: TECHNICAL ANALYSIS - SETTLEMENT AND POTENTIAL FOR
COVER SLOPE REVERSAL AND/OR COVER LAYER CRACKING ................................................. 35 
INTERROGATORY WHITEMESA RECPLAN Rev5.0 R313-24-4; 10cfr40 APPENDIX A
CRITERION 4; INT 08/1: TECHNICAL ANALYSIS –EROSION STABILITY EVALUATION ......... 51 
INTERROGATORY WHITEMESA RECPLAN Rev. 5.0; R313-24-4; 10CFR40 APPENDIX A
CRITERION 1; INT 09/1: LIQUEFACTION .......................................................................................... 58 
INTERROGATORY WHITEMESA RECPLAN 5.0 R313-24-4; 10CFR40 APPENDIX A, CRITERION
6; INT 10/1: TECHNICAL ANALYSES - FROST PENETRATION ANALYSIS ................................ 63 
INTERROGATORY WHITE MESA RECPLAN REV 5.0 R313-24-4; 10CFR40 APPENDIX A; INT
11/1: VEGETATION AND BIOINTRUSION EVUALATION AND REVEGETATION PLAN ........... 67 
INTERROGATORY WHITEMESA RECPLAN REV 5.0 R313-24-4; 10CFR40 APPENDIX A,
CRITERION 6(4); INT 12/1: REPORT RADON BARRIER EFFECTIVENESS .................................... 75 
INTERROGATORY WHITEMESA RECPLAN REV 5.0 R313-24-4; 10CFR40, APPENDIX A,
CRITERION 6(6); INT 13/1: CONCENTRATIONS OF RADIONUCLIDES OTHER THAN RADIUM
IN SOIL ...................................................................................................................................................... 83 
INTERROGATORY WHITE MESA RECPLAN REV 5.0 R313-24-4; 10CFR40 APPENDIX A; INT
14/1: COVER TEST SECTION AND TEST PAD MONITORING PROGRAMS ................................... 90 
INTERROGATORY WHITEMESA RECPLAN REV 5.0 R313-24-4; 10CFR40, APPENDIX A,
CRITERION 9; INT 15/1: FINANCIAL SURETY ARRANGEMENTS................................................ 101 
INTERROGATORY WHITE MESA REC PLAN REV 5.0 R313-15-501; INT 16/1; RADIATION
PROTECTION MANUAL ....................................................................................................................... 104 
INTERROGATORY WHITE MESA REC PLAN REV 5.0 R313-15-1002; INT 17/1; RELEASE
SURVEYS ................................................................................................................................................ 105 
INTERROGATORY WHITE MESA REC PLAN REV 5.0 R313-12; INT 18/1: INSPECTION AND
QUALITY ASSURANCE ........................................................................................................................ 106 
August 15, 2012
INTERROGATORY WHITE MESA REC PLAN REV 5.0 R313-24; 10 CFR 40.42(J); INT 19/1:
REGULATORY GUIDANCE .................................................................................................................. 107 
INTERROGATORY WHITE MESA REC PLAN REV 5.0 R313-24,;10 CFR 40 APPENDIX A
CRITERION 6(6); INT 20/1: SCOPING, CHARACTERIZATION, AND FINAL SURVEYS ............. 108 

ATTACHMENTS

ATTACHMENT A Supporting Documentation for Interrogatory 01/1: Asbestos Inspection
Reports
ATTACHMENT B Supporting Documentation for Interrogatory 02/1: April 2012 Cover
Material Field Investigation and Laboratory Testing Results
ATTACHMENT C Supporting Documentation for Interrogatory 02/1 and 08/1: Revised
Appendix G, Erosional Stability Evaluation, to the Updated Tailings Cover
Design Report (Appendix D of Reclamation Plan, Revision 5.0)
ATTACHMENT D Supporting Documentation for Interrogatory 06/1: Revised Appendix E,
Slope Stability Analysis, to the Updated Tailings Cover Design Report
(Appendix D of Reclamation Plan, Revision 5.0)
ATTACHMENT E Supporting Documentation for Interrogatory 7/1: Updated Settlement
Analyses
ATTACHMENT F Supporting Documentation for Interrogatory 9/1: Updated Liquefaction
Analyses
ATTACHMENT G Supporting Documentation for Interrogatory 11/1: Revised Appendix D,
Vegetation and Biointrusion, to the Updated Tailings Cover Design Report
(Appendix D of Reclamation Plan, Revision 5.0)
ATTACHMENT H Supporting Documentation for Interrogatory 12/1: Revised Appendix C,
Radon Emanation Modeling, to the Updated Tailings Cover Design
Report (Appendix D of Reclamation Plan, Revision 5.0)
ATTACHMENT I Supporting Documentation for Interrogatory 13/1: The Radium
Benchmark Dose Approach

August 15, 2012
Interrogatory 01/1: R313-24-4; 10CFR40.31(H): Responses to Reclamation Plan Rev. 4.0 Interrogatories Page 1 of 117
INTERROGATORY WHITEMESA RECPLAN REV 5.0; R313-24-4; 10CFR40.31(H); INT 01/1:
RESPONSES TO RECLAMATION PLAN REV. 4.0 INTERROGATORIES
REGULATORY BASIS:
UAC R313-24-4 invokes the following requirement from 10CFR40.31(h): An application for a license to
receive, possess, and use source material for uranium or thorium milling or byproduct material, as
defined in 10CFR40, at sites formerly associated with such milling shall contain proposed written
specifications relating to milling operations and the disposition of the byproduct material to achieve the
requirements and objectives set forth in appendix A of 10CFR40. Each application must clearly
demonstrate how the requirements and objectives set forth in appendix A of 10CFR40 have been
addressed. Failure to clearly demonstrate how the requirements and objectives in Appendix A have been
addressed shall be grounds for refusing to accept an application.
INTERROGATORY STATEMENT:
The Division has reviewed the responses to Reclamation Plan 4.0 and is not asking for additional
information at this time; however, the Division reserves the right and may submit comments and/or
additional interrogatories following completion of review of the Denison Mines (USA) Corp (DUSA)
response document dated December 28, 2011 (DUSA 2011).
Response (May 31, 2012):
No response required.

Response (August 15, 2012):
Denison noted in their response to Interrogatory 01/1 of Denison (2011) that a facility-
wide inspection to determine the presence of asbestos in building materials in the milling
facility would be conducted for Denison in the spring of 2012. These inspections have
been completed and the inspection reports are provided in Attachment A. The locations
inspected included:
• Administration Building;
• Mill Building, Boiler Plant, Scale House, and the Sample Plant;
• Maintenance-Warehouse Facility; and
• SX Building.
These reports will be included in the next version of the Reclamation Plan.

Reference for Response (August 15, 2015):
Denison Mines (USA) Corp. (Denison), 2011. Responses to Interrogatories – Round 1
for Reclamation Plan, Revision 4.0, November 2009. December.
BASIS FOR INTERROGATORY:
The State transmitted Interrogatory Round 1 following its review and evaluation of Reclamation Plan
Rev. 4.0 (o/a September 10, 2010). A meeting was held on October 5, 2010 with DUSA personnel
regarding Denison’s plan to prepare and submit a Reclamation Plan Rev. 5.0 incorporating an
evapotranspiration cover system. The State prepared and issued Interrogatory Round 1A for the purpose
of giving guidance to DUSA on topics that it must address in Reclamation Plan Rev. 5.0 for matters
relating to the evapotranspiration cover system. A complete review of DUSA’s December 28, 2011
August 15, 2012
Interrogatory 01/1: R313-24-4; 10CFR40.31(H): Responses to Reclamation Plan Rev. 4.0 Interrogatories Page 2 of 117
response to the Round 1 and Round 1A must be performed to ensure that all issues that are still relevant
have been adequately addressed.
The Division received a letter from Denison Mines (USA) Corp (DUSA ) dated December 28, 2011
(DUSA 2011) that provided responses) to: (i) Round 1 and Round 1A interrogatories that were submitted
to DUSA on Rev. 4.0 of the Reclamation Plan Rev. (DUSA 2009) in 2010 (Division 2010); and (ii)
Round 1A interrogatories that were submitted to DUSA in 2011 (Division 2011) regarding an alternative
cover system design that was proposed by DUSA in 2010 (see DUSA letter dated October 6, 2010 [DUSA
2010]. The December 28, 2011 response document was forwarded to URS Corporation on February 23,
2012 and is currently under review.
REFERENCES:
Denison Mines (USA) Corp. 2009. Reclamation Plan, White Mesa Mill, Blanding, Utah, Radioactive
Materials License No. UT1900479, Revision 4.0, November 2009.
Denison Mines (USA) Corp. 2011. Responses to Supplemental Interrogatories – Round 1A for
Reclamation Plan, Revision 4.0, November 2009. December 28, 2011.
Division (Utah Division of Radiation Control) 2010. Denison Mines (USA) Corporation Reclamation
Plan, Revision 4.0, November 2009: Interrogatories – Round 1. September 2010
Division (Utah Division of Radiation Control) 2011. Denison Mines (USA) Corporation Reclamation
Plan, Revision 4.0, November 2009: Supplemental Interrogatories – Round 1A. April 2011.

August 15, 2012
Interrogatory 02/1: R313-24-4; 10CFR40.Appendix A, Criterion 4: Engineering Drawings Page 3 of 117
INTERROGATORY WHITEMESA RECPLAN REV 5.0; R313-24-4; 10CFR40, APPENDIX A,
CRITERION 4; INT 02/1: ENGINEERING DRAWINGS
REGULATORY BASIS:
UAC R313-24-4 invokes the following requirement from 10CFR40, Appendix A, Criterion 4: “The
following site and design criteria must be adhered to whether tailings or wastes are disposed of above or
below grade:
… (c) Embankment and cover slopes must be relatively flat after final stabilization to minimize erosion
potential and to provide conservative factors of safety assuring long-term stability. The broad objective
should be to contour final slopes to grades which are as close as possible to those which would be
provided if tailings were disposed of below grade; this could, for example, lead to slopes of about 10
horizontal to 1 vertical (10h:1v) or less steep. In general, slopes should not be steeper than about 5h:1v.
Where steeper slopes are proposed, reasons why a slope less steep than 5h:1v would be impracticable
should be provided, and compensating factors and conditions which make such slopes acceptable should
be identified.
(d) A full self-sustaining vegetative cover must be established or rock cover employed to reduce wind and
water erosion to negligible levels.
Where a full vegetative cover is not likely to be self-sustaining due to climatic or other conditions, such as
in semi-arid and arid regions, rock cover must be employed on slopes of the impoundment system. The
Executive Secretary will consider relaxing this requirement for extremely gentle slopes such as those
which may exist on the top of the pile.
….Furthermore, all impoundment surfaces must be contoured to avoid areas of concentrated surface
runoff or abrupt or sharp changes in slope gradient. In addition to rock cover on slopes, areas toward
which surface runoff might be directed must be well protected with substantial rock cover (rip rap). In
addition to providing for stability of the impoundment system itself, overall stability, erosion potential,
and geomorphology of surrounding terrain must be evaluated to assure that there are not ongoing or
potential processes, such as gully erosion, which would lead to impoundment instability.”

NUREG-1620, Section 2.5.3: The assessment of the disposal cell cover design and engineering parameters
will be acceptable if it meets the following criteria:
(3) Details are presented (including sketches) of the disposal cell cover termination at boundaries, with any
considerations for safely accommodating subsurface water flows.
(4) A schematic diagram displaying various disposal cell layers and thicknesses is provided. The particle size
gradation of the disposal cell bedding layer and the rock layer are established to ensure stability against
particle migration during the period of regulatory interest (NRC 1982).
INTERROGATORY STATEMENT:
Drawing REC-1: Provide design details for Discharge Channel.
Drawing REC-3: Provide design details for Discharge Channel. Identify the limits of the proposed
Sedimentation Pond.
Establish and indicate on the appropriate drawing(s) the location of the main drainage channel.
Demonstrate that the Cell 1 embankment and appurtenant apron are designed to remain stable under
PMP conditions.
August 15, 2012
Interrogatory 02/1: R313-24-4; 10CFR40.Appendix A, Criterion 4: Engineering Drawings Page 4 of 117
Drawing TRC-2: Correct the location shown by green dashes for the “Approximate limit of compacted
cover,”
Drawing TRC-4: State where “Filter Layer” is defined. Link Rock Apron A and Rock Apron B to
characteristics presented in the table at Detail 1/8.
Drawing TRC-5: In Sections A/3 and B/3, indicate the cover thickness to be 9 feet minimum. State the
maximum tailings elevation on the North end of each section.
Drawing TRC-6: Please explain why the Compacted Cover cannot continue through the entire sections
rather that terminating as “wedges”.
Drawing TRC-7: Please explain why the Compacted Cover cannot continue through the entire sections
rather that terminating as “wedges”. State maximum slope on transitional slopes in Section A/3, B/3, and
C/3 to be 5:1. State maximum tailings elevations in each section.
Drawing TRC-8: Revise both the Plan and the Elevation of Detail 1/8 to refer to the table provided below
rather than stating D50 = 7.4” min. State where “Filter Layer” is defined. Show the “Riprap Filter
Layer” on the side slopes of Details 3/5, Detail 4/8, and Detail 5/8 or otherwise resolve the conflict
involving “Riprap Filter Layer” that exists between Detail 1/8 and the details cited. State where “Clay
Liner” called out in Detail 4/8 is defined. Justify terminating the “Clay Liner” shown in Detail 4/8 at the
exterior extreme (of top) of the “Radon Attenuation and Grading Layer”. State the cover thickness
shown in Detail 4/8 to be 9 feet minimum. Show the correct maximum tailings elevations in Details 6/8
(presently incorrectly stated) and 7/8 (presently not stated).
Response (August 15, 2012):
This response supersedes the response provided in the previous response document
dated May 31, 2012.
Denison conducted a field investigation on April 19, 2012 to supplement existing soils
data and further evaluate the geotechnical properties of the potential cover material.
Test pits were excavated at select on-site stockpiles and representative bulk samples
were collected for laboratory testing. The locations of the test pits are shown on Figure
1 in Attachment B.1. Figure 1 also shows the test pit locations from the field
investigation conducted for the on-site stockpiles on October 10, 2010. The test pit logs
from the April 2012 investigation are provided in Attachment B.1.
Laboratory testing on the collected samples from the April 2012 investigation was done
in two phases. Phase 1 testing included Atterberg limits, specific gravity, and gradation
(including hydrometer). Based on evaluation of the Phase 1 laboratory testing results for
the April 2012 investigation and further evaluation of the laboratory testing conducted on
samples from the October 2010 investigation, in addition to information provided by
Benson (2012), the stockpile soils were categorized into four soil categories. The
categories included topsoil, fine-grained soils, broadly graded soils, and uniformly
graded soils. Select samples from the April 2012 investigation from these categories
were selected for Phase 2 testing which included standard Proctor compaction,
saturated hydraulic conductivity, and moisture retention tests. The laboratory testing
reports are provided as Attachment B.2. The results of the 2010 and 2012 laboratory
testing are provided in Table 1 in Attachment B.2 and Figures 1 and 2 present the
results of the gradation testing and identify the soil categories.
The results of the 2010 and 2012 laboratory testing were used to revise the technical
analyses for the cover design. The resulting cover design is discussed in the responses
to Interrogatory 12/1. The Drawings will be updated to reflect the revised cover design in
the next revision of the Reclamation.
August 15, 2012
Interrogatory 02/1: R313-24-4; 10CFR40.Appendix A, Criterion 4: Engineering Drawings Page 5 of 117
The following paragraphs respond directly to the interrogatory comments listed above.
The Drawings will be updated to provide design details for the Discharge Channel and
identify the limits of the Sedimentation Pond.
The Cell 1 embankment and toe are designed to be erosionally stable from peak runoff
from the PMP. Erosion protection is provided by riprap on the reclaimed slope of the
Cell 1 embankment, and by a riprap apron at the toe of the embankment. The updated
erosional stability analyses, including for the embankment and toe apron, are provided in
Attachment C as a revised Appendix G that will be included in the next version of the
Updated Tailings Cover Design Report (Appendix D of the Reclamation Plan).
Cell 1 will be cleaned of contaminated materials upon reclamation and the materials will
be placed in the tailings cells. A portion of the Cell 1 area will be used for permanent
disposal of contaminated materials and mill debris. The remaining area of Cell 1 will be
breached and converted to a sedimentation basin. The Sedimentation Pond is designed
to grade at a 0.1 percent slope northwest towards the Discharge Channel. This area is
designed to be erosionally stable from peak runoff from the PMP with topsoil and
vegetation. A rock apron is included at the transition between the vegetated surface of
the Sedimentation Basin and the bedrock surface at the entrance of the Discharge
Channel. Although channeling in this area would not cause erosional issues for the Cell
1 embankment, Denison has revised the grading to include a drainage swale along the
center of the Sedimentation Pond area parallel to the toe of the Cell 1 embankment and
draining to the west towards the Discharge Channel as shown in Figure G.1 of
Attachment C.
The location of the “approximate limit of compacted cover” will change due to revisions
to the cover design and the updated limit will be provided on Drawing TRC-2 in the next
revision of the Reclamation Plan after approval of the conceptual cover design. The
compacted cover was shown correctly as terminating as “wedges” on Drawings TRC-7
and 8 in Reclamation Plan Rev. 5.0. The compacted cover is the cover layer that will be
compacted to 95 percent of standard Proctor dry density. In some areas of Cell 2 and 3,
the placed interim cover is thicker than required for the cover design and/or additional
interim cover is required to meet grading requirements. As a result, there are areas in
Cell 2 and 3 that do not require the compacted cover layer to meet radon emanation
requirements. This is discussed further with the revised radon modeling results provided
in Attachment H. A minimum compacted layer will be included for the final design and
the drawings will be updated to incorporate this change as well as the revised cover
design. A note will be added to the drawings to provide additional clarification.
Notes will be added to Drawing TRC-4 to clarify details on the filter and aprons provided
on Drawing TRC-8.
A minimum cover thickness will be added to Drawing TRC-5 for Sections A/3 and B/3.
The maximum tailings elevation will be added to the north end of Sections A/3 and B/3.
The maximum transitional slopes will be stated as 10H:1V on Drawings TRC-6 and
TRC-7.
Drawing TRC-8 will be revised to reference the table for the Plan and Elevation of Detail
1/8. The filter layer and clay liner will be defined on Drawing TRC-8. The riprap filter
layer will be added to the Details 3/5, 4/8, and 5/8. The termination of the clay liner will
be revised to terminate at the bottom of the radon attenuation and grading layer and a 3-
ft berm will be added at the termination location. The minimum cover thickness will be
August 15, 2012
Interrogatory 02/1: R313-24-4; 10CFR40.Appendix A, Criterion 4: Engineering Drawings Page 6 of 117
added to Detail 4/8. The maximum tailings elevations will be corrected for Detail 6/8 and
will be added to Detail 7/8

References for Response 1 (August 15, 2012):
Benson, Craig, 2012. Electronic communication from Craig Benson, University of
Wisconsin-Madison, to Melanie Davis, MWH Americas, Inc., regarding evaluation
of gradations performed for potential cover soils for White Mesa, May 20.

BASIS FOR INTERROGATORY:
The Licensee should resolve conflicts, clarify ambiguities, and provide missing information to properly
document the proposed designs.
Upstream of the discharge channel, it appears that drainage from precipitation events would likely create
a random main drainage channel location in Cell 1. It is not desirable for this drainage channel to have
the northern toe of the Cell 1 dike as a channel wall. Controlling the location of drainage channeling in
Cell 1 appears to be important. Without establishing the location of the main drainage channel location,
the Cell 1 embankment and appurtenant apron would need to be designed to be stable under PMP
drainage channel wall depth and velocities. Note: Drawing TRC-4 shows topsoil and vegetation east of
the riprap rock in Cell 1 and bedrock to the west.
REFERENCES:
NRC 1992. “Preparation of Environmental Reports for Uranium Mills,” Regulatory Guide 3.8, October,
1992.
NRC 2003. Standard Review Plan for the Review of a Reclamation Plan for Mill Tailings Sites under
Title II of the Uranium Mill Tailings Radiation Control Act of 1978. Washington DC, June 2003.
NRC 2008. “Standard Format and Content Of License Applications for Conventional Uranium Mills,”
Draft Regulatory Guide DG-3024, Ma, 2008.
August 15, 2012
Interrogatory 03/1: R313-24-4; 10CFR40.Appendix A, Criteria 1 and 4: Construction Quality Assurance/Quality Control Plan, Cover Constructability,
and Filter and Rock Riprap Layer Criteria and Placement Page 7 of 117
INTERROGATORY WHITEMESA RECPLAN REV. 5.0; R313-24-4; 10CFR40 APPENDIX A
CRITERIA 1 AND 4; INT 03/1: CONSTRUCTION QUALITY ASSURANCE/QUALITY
CONTROL PLAN, COVER CONSTRUCTABILITY, AND FILTER AND ROCK RIP RAP
LAYER CRITERIA AND PLACEMENT
REGULATORY BASIS:
UAC R313-24-4 invokes the following requirement from 10CFR40, Appendix A, Criterion 1: “ The general
goal or broad objective in siting and design decisions is permanent isolation of tailings and associated
contaminants by minimizing disturbance and dispersion by natural forces, and to do so without ongoing
maintenance. For practical reasons, specific siting decisions and design standards must involve finite
times (e.g., the longevity design standard in Criterion 6)…
UAC R313-24-4 invokes the following requirement from 10CFR40, Appendix A, Criterion 4: “The
following site and design criteria must be adhered to whether tailings or wastes are disposed of above or
below grade:
… (c) Embankment and cover slopes must be relatively flat after final stabilization to minimize erosion
potential and to provide conservative factors of safety assuring long-term stability. The broad objective
should be to contour final slopes to grades which are as close as possible to those which would be
provided if tailings were disposed of below grade; this could, for example, lead to slopes of about 10
horizontal to 1 vertical (10h:1v) or less steep. In general, slopes should not be steeper than about 5h:1v.
Where steeper slopes are proposed, reasons why a slope less steep than 5h:1v would be impracticable
should be provided, and compensating factors and conditions which make such slopes acceptable should
be identified.
(d) A full self-sustaining vegetative cover must be established or rock cover employed to reduce wind and
water erosion to negligible levels.
Where a full vegetative cover is not likely to be self-sustaining due to climatic or other conditions, such as
in semi-arid and arid regions, rock cover must be employed on slopes of the impoundment system. The
Executive Secretary will consider relaxing this requirement for extremely gentle slopes such as those
which may exist on the top of the pile.
….Furthermore, all impoundment surfaces must be contoured to avoid areas of concentrated surface
runoff or abrupt or sharp changes in slope gradient. In addition to rock cover on slopes, areas toward
which surface runoff might be directed must be well protected with substantial rock cover (rip rap). In
addition to providing for stability of the impoundment system itself, overall stability, erosion potential,
and geomorphology of surrounding terrain must be evaluated to assure that there are not ongoing or
potential processes, such as gully erosion, which would lead to impoundment instability.”
INTERROGATORY STATEMENT:
Refer to Section 5 of Attachment B, Construction Quality Assurance/Quality Control Plan, to the
Reclamation Plan, Rev. 5.0: Please provide the following:
1. In Sections 5.3 and 5.4, clarify the nature and characteristics of wastes that would be placed into
the reclaimed Cell 1 footprint area within which the 1-foot-thick compacted clay liner would first
be installed. Verify whether and state consistently throughout the CQA/CQC Plan whether any
uranium mill tailings materials would be placed into the clay-lined Cell 1 footprint area. If no
tailings will be placed in the Cell 1 area, then change the name (“Cell 1 Tailings Area”) given in
the T.O.C., and Sections 1.1, 5.3, 5.4.2, and 5.6 of the CQA/CQA Plan to “Cell 1 Contaminated
Soil and Demolition Debris Disposal Area” or other name as appropriate, and revise the
August 15, 2012
Interrogatory 03/1: R313-24-4; 10CFR40.Appendix A, Criteria 1 and 4: Construction Quality Assurance/Quality Control Plan, Cover Constructability,
and Filter and Rock Riprap Layer Criteria and Placement Page 8 of 117
descriptions of waste materials to be placed into the clay-lined Cell 1 area as needed throughout
the CQA/CQC Plan to be consistent with the proposed disposal plan.
Response 1 (May 31, 2012 and August 15, 2012):
No tailings are planned to be disposed of within the footprint of the 1-foot-thick clay liner
to be constructed in the reclaimed Cell 1 area. Sections 1.1, 5.3, 5.4.2, and 5.6 of the
CQA/CQC Plan will be revised to change the designation of “Cell 1 Tailings Area” to
“Cell 1 Disposal Area”. In addition, the designation of “Cell 1 Tailings Area” will be
revised to “Cell 1 Disposal Area" in Sections 3.3 and 8.1 of the Technical Specifications
and Section 3.2 of the main text of the Reclamation Plan.
Sections 5.3.3 and 5.4.2 of the CQA/CQC Plan will be revised to denote that the
materials to be placed in the Cell 1 Disposal Area will consist of contaminated materials
and mill debris from the mill site decommissioning, and that tailings will not be placed in
the Cell 1 Disposal Area. To be consistent with the CQA/CQC Plan, Section 3.2 of the
main text of the Reclamation Plan will be revised to clarify that materials to be placed in
the Cell 1 Disposal Area will consist of contaminated materials and mill debris from the
mill site decommissioning, and that tailings will not be placed in the Cell 1 Disposal Area

2. In Sections 5.6.4 and 5.6.5, provide a detailed justification to support the technical
appropriateness and the constructability of the proposed topslope areas of the proposed cover
system having such extremely flat slopes (e.g. 0.1 to 0.82 %). Provide information
demonstrating that such topslope areas of the cover could be constructed with such shallow
inclinations maintained continuously over the long distances that are required based on the
currently proposed over design drawings such that no areas of runoff concentration or areas
where ponding or could occur would result. Provide information justifying that appropriate
required tolerances specified for final grades for ensuring conformance to the proposed
extremely flat slope inclinations can be maintained and measured in the field with sufficient
accuracy to ensure compliance with the specified slope requirements.
Response 2 (August 15, 2012):
This response supersedes the response provided in the previous response document
dated May 31, 2012.
The proposed top surface cover slopes range from 0.5 to 1 percent, not 0.1 to 0.82
percent as listed in Comment 2. Cover with similar slopes have been permitted and
constructed for Uranium Mill Tailings Radiation Control Act (UMTRCA) Title I and II sites
including:
• Falls City Title I site in Texas (less than 1% cover slopes)
• Bluewater Title II site in New Mexico (0.5 – 4% cover slopes)
• Conquista Title II site in Texas (0.5 – 1% cover slopes)
• Highland Title II site in Wyoming (0.5 – 2% cover slopes)
• Panna Maria Title II site in Texas (0.5% cover slopes)
• Ray Point Title II site in Texas (0.5 – 1% cover slopes)
• Sherwood Title II site in Washington (0.25% cover slopes)
• L-Bar Title II site in New Mexico (0.1% cover slopes)
Settlement monuments currently exist in Cell 2 and the eastern portion of Cell 3 where
interim cover has been placed, and the monuments have been measured since 1989
August 15, 2012
Interrogatory 03/1: R313-24-4; 10CFR40.Appendix A, Criteria 1 and 4: Construction Quality Assurance/Quality Control Plan, Cover Constructability,
and Filter and Rock Riprap Layer Criteria and Placement Page 9 of 117
and 1999, respectively. The standard operating procedure (SOP) for settlement
monitoring was revised in October 2011 to incorporate comments provided by the
Division in their letter dated July 2, 2012 (DRC, 2012). The updated SOP has been
used since October 2011 for settlement monitoring. For the remainder of Cell 3, and for
Cells 4A and 4B, settlement monuments will be installed after placement of interim cover
using the procedures provided in the updated SOP. Monuments will be monitored on a
regular basis in order to verify that 90 percent of the settlement due to tailings
dewatering and interim cover placement has occurred prior to construction of the final
cover. Additional interim cover, if necessary, will be placed in any low areas in order to
maintain positive drainage of the cover surface.
Settlement analyses were revised and are discussed in the responses to Interrogatory
07/1. The results of the settlement analyses indicate that the majority of the total
settlement due to final cover placement and creep will occur within the first five years
after placement of the final cover. During this time period, additional fill can be placed in
any low areas in order to maintain positive drainage of the cover surface. Settlement
occurring over five years after placement of the final cover ranges from 0.52 to 0.83 feet,
with a maximum potential total differential settlement on the order of 0.31 feet. This
estimated settlement is sufficiently low such that ponding is not expected to occur with a
cover slope of 0.5 percent. In addition, it is not expected that the differential settlement
is significant enough for slope reversal to occur.
The recommended tolerances provided Section 5.6.5 of the CQA/CQC Plan are
sufficient to meet the specified grading for the final cover surface.

3. In Section 5.7.1.2, described material sampling frequency and filter gradation and filter
permeability calculations (with associated acceptance criteria) that will be performed for the
granular materials used in constructing the granular filter layer beneath the riprap layer on the
sideslopes, to ensure that all applicable filter acceptance criteria will be achieved between the
granular filter layer and each topslope cover layer component.
Response 3 (August 15, 2012):
This response supersedes the response provided in the previous response document
dated May 31, 2012.
Section 5.7.1.2 will be revised to include a testing requirement for particle size
distribution testing prior to placement, using ASTM D-422. The recommended testing
frequency is at least one test per 10,000 cubic yards of filter material placed, or when
filter material characteristics show significant variation. The filter material gradation
requirements will be updated based on the revised filter gradation presented in
Attachment C. The procedure from NRCS (1994) was used to determine the filter
gradation limits. In addition, criteria provided in Nelson et al. (1986) and Cedegren
(1989) were evaluated for the filter gradation limits.

Reference for Response 3 (August 15, 2012):
Cedegren, H.R., 1989. Seepage, Drainage, and Flow Nets. Equation 5.3. 3rd Edition.
John Wiley & Sons, Inc., New York.
August 15, 2012
Interrogatory 03/1: R313-24-4; 10CFR40.Appendix A, Criteria 1 and 4: Construction Quality Assurance/Quality Control Plan, Cover Constructability,
and Filter and Rock Riprap Layer Criteria and Placement Page 10 of 117
Natural Resource Conservation Service (NRCS), 1994. Gradation Design of Sand and
Gravel Filters, U.S. Department of Agriculture, National Engineering Handbook,
Part 633, Chapter 26, October.
Nelson, J., S. Abt, R. Volpe, D. van Zyl, N. Hinkle, and W. Staub, 1986. "Methodologies
for Evaluation of Long-term Stabilization Designs of Uranium Mill Tailings
Impoundments." NUREG/CR-4620, U.S. Nuclear Regulatory Commission, June.

4. In Section 5.7.1, specify the minimum required thickness of the rock riprap layer on the
sideslopes – equal to 1.5 times the D50 of the rock rip diameter of 7.4 inches, or the D100 of the
rock rip rap materials, whichever is greater, as per NUREG-1623 (NRC 2002) –for clarity and
transparency in the CQA/CQC process.

Response 4 (May 31, 2012 and August 15, 2012):
Section 5.7.1 of the CQA/CQC Plan will be revised to include the minimum required
thickness of the side slope riprap of 1.5 times the D50 or the D100 of the riprap, whichever is greater. To be consistent with the CQA/CQC Plan, Section 8.2.4 of the Technical
Specifications will be will be revised to include the minimum required thickness of the
side slope riprap of 1.5 times the D50 or the D100 of the riprap, whichever is greater.

5. In Sections 5.7.2, 5.7.4, and 5.7.5 provide additional details regarding the minimum thickness for
placed riprap layer material and requirements for using specialized equipment or rearranging of
rocks by hand, as needed, in accordance with the specified minimum required final thickness of
the rock rip rap layer. Also provide additional details and requirements regarding procedures to
be used to verify proper in-place rock riprap layer thickness and procedures for gradation testing
in a completed initial riprap layer section, and for visual observations of the test section by field
personnel. Provide criteria and procedures for testing additional test sections where
observations suggest rock placement appears to be inadequate or where difficulties are
experienced during rock place activities.
Response 5 (May 31, 2012 and August 15, 2012):
Sections 5.7.2 and 5.7.4 of the CQA/CQC Plan will be revised to include reference to
Section 5.7.1 for the minimum required thickness for the riprap layers (see Response 4
above).
Section 5.7.2 of the CQA/CQC Plan will be revised to include the following text at the
end of the section “Hand placing will be required only to the extent necessary to secure
the results specified above.”
Section 5.7.4 of the CQA/CQC Plan will be revised to include the following text at the
end of the section “Riprap layer thickness will be directly measured as outlined in
Section 5.7.2. A measurement device (i.e. tape measure) may be used to determine the
distance from the top of the bedding or filter layer to the top of the riprap layer.”
Section 5.7.2 of the CQA/CQC Plan will be revised to include the following text “An initial
section of each type of riprap constructed shall be visually examined and used to
evaluate future riprap placement. The initial section will be constructed with material
meeting gradation and riprap thickness requirements.”
August 15, 2012
Interrogatory 03/1: R313-24-4; 10CFR40.Appendix A, Criteria 1 and 4: Construction Quality Assurance/Quality Control Plan, Cover Constructability,
and Filter and Rock Riprap Layer Criteria and Placement Page 11 of 117
Section 5.7.1.1 of the CQA/CQC Plan will be revised to include the following text at the
end of the section “Gradations will also be performed at the direction of the QC
Technician for any locations considered inadequate based on visual inspection by the
QC Technician, or if difficulties are experienced by the Contractor during rock
placement.”

BASIS FOR INTERROGATORY:
In Section 5.4.4 of the CQA.CQC it states that backfill materials placed around placed demolition debris
might include stockpiled soils, contaminated soils, tailings and or other approved materials [as approved
by the Construction Manager and CQA officer]; however, in other sections of the CQA/CQAC Plan and
in the Reclamation Plan it is indicated that no tailings placement would occur in the Cell 1 area.
The ability to accurately construct the extremely flat topslope areas with a uniform slope to the proposed
specified grades and within the associated allowable tolerances, and the ability to accurately verify that
these flat slopes have been constructed uniformly and without the occurrence of areas of flow
concentrations or areas where ponding of water could occur has not been adequately demonstrated.
It has not been adequately demonstrated that all applicable filter layer criteria have been met for all
interfaces that would occur between the sideslope filter layer and topslope cover components.
NUREG-1623 (NRC 2002), Section 2.1.2 recommends that the minimum required thickness of a rock
riprap layer be no less than 1.5 times the D50 of the rock riprap materials, or the D100 of the rock rip rap
materials, whichever is greater.
NUREG-1623 (NRC 2002), Appendix F provides specific recommendations regarding rock rip placement
procedures and procedures for conducting testing and visual observations during rock rip rap placement
that should be adhered to during construction and that should be addressed in the CQA/CQC Plan.
REFERENCES:
NRC 2002. U.S. Nuclear Regulatory Commission, “Design of Erosion Protection for Long-Term
Stability”, NUREG-1623, September 2002.
August 15, 2012
Interrogatory 04/1: R313-24-4; 10CFR40.Appendix A, Criterion 4: Void Space Criteria and Debris, Rubble Placement and Soil/Backfill Requirements
Page 12 of 117
INTERROGATORY WHITEMESA RECPLAN REV5.0; R313-24-4; 10CFR40, APPENDIX A,
CRITERION 4; INT 04/1: VOID SPACE CRITERIA AND DEBRIS, RUBBLE PLACEMENT
AND SOIL/BACKFILL REQUIREMENTS
REGULATORY BASIS:
UAC R313-24-4 invokes the following requirement from 10CFR40, Appendix A, Criterion 4: “The following
site and design criteria must be adhered to whether tailings or wastes are disposed of above or below
grade:
…(c) Embankment and cover slopes must be relatively flat after final stabilization to minimize erosion
potential and to provide conservative factors of safety assuring long-term stability. The broad objective
should be to contour final slopes to grades which are as close as possible to those which would be
provided if tailings were disposed of below grade; this could, for example, lead to slopes of about 10
horizontal to 1 vertical (10h:1v) or less steep. In general, slopes should not be steeper than about 5h:1v.
Where steeper slopes are proposed, reasons why a slope less steep than 5h:1v would be impracticable
should be provided, and compensating factors and conditions which make such slopes acceptable should
be identified.
(d) A full self-sustaining vegetative cover must be established or rock cover employed to reduce wind and
water erosion to negligible levels.
Where a full vegetative cover is not likely to be self-sustaining due to climatic or other conditions, such as
in semi-arid and arid regions, rock cover must be employed on slopes of the impoundment system. The
Executive Secretary will consider relaxing this requirement for extremely gentle slopes such as those
which may exist on the top of the pile.
…Rock covering of slopes may be unnecessary where top covers are very thick (or less); bulk cover
materials have inherently favorable erosion resistance characteristics; and, there is negligible drainage
catchment area upstream of the pile and good wind protection as described in points (a) and (b) of this
criterion.
Furthermore, all impoundment surfaces must be contoured to avoid areas of concentrated surface runoff
or abrupt or sharp changes in slope gradient. In addition to rock cover on slopes, areas toward which
surface runoff might be directed must be well protected with substantial rock cover (rip rap). In addition
to providing for stability of the impoundment system itself, overall stability, erosion potential, and
geomorphology of surrounding terrain must be evaluated to assure that there are not ongoing or
potential processes, such as gully erosion, which would lead to impoundment instability.

INTERROGATORY STATEMENT:
1. Refer to Section 6.0 of Appendix G and Section 7.0 of Attachment A (Technical Specifications) of
the Reclamation Plan, Rev. 5.0:
a. Please define and justify a maximum void space percentage that will be allowed when disposing
of demolition and decommissioning debris fragments and rubble in Cell 1.
Response 1(1a) (May 31, 2012 and August 15, 2012):
The procedures for sizing and placement of debris were developed from mill demolition
and debris placement at other uranium mill sites in the western US. The procedures
reflected in the Technical Specifications were based on whether the demolition materials
were compressible. These procedures are incorporated in the Technical Specifications,
as summarized below.
August 15, 2012
Interrogatory 04/1: R313-24-4; 10CFR40.Appendix A, Criterion 4: Void Space Criteria and Debris, Rubble Placement and Soil/Backfill Requirements
Page 13 of 117
Compressible materials are to be crushed and covered with soils, and incompressible
materials are to be placed in the cell, with the void spaces outside of the materials filled
with soils. Internal void spaces of incompressible materials are to be filled with soil
where possible, or grout if needed.
Materials such as pipe and tubing have a varying degree of compressibility, depending
on the diameter and wall thickness of the pipe. Pipe with a 12-inch diameter or larger is
to be filled with grout or soil for burial, and pipe with smaller diameter was crushed
before burial.
A requirement for the maximum void space percentage is not included because there is
no practical method for measuring this percentage in the placed debris or the compacted
soil during or after placement. Therefore a method specification reflecting best
management practice from other projects was incorporated in the Technical
Specifications.

b. Describe, in detail, construction practices that will enable satisfying this specified limit.
Response 1(1b) (May 31, 2012 and August 15, 2012):
The debris is to be spread in a layer such that structural shapes or other large pieces do
not lie on across or on top of each other, to prevent nesting. The soil to be used for filling
voids around the debris is to be spread in loose layers over the debris, and worked into
and around the debris materials until the void spaces are minimized. Enough soil should
be placed so that the surface is accessible with tracked equipment. The debris is then
walked with heavy tracked equipment to compress the debris as much as possible into
the underlying soil. After additional soil fill placement, the soil and debris lift can be
compacted with compaction equipment. From the proposed specifications:
“The debris, contaminated soils and other materials for the first lift will be placed
to a depth of up to four feet thick, in a bridging lift, to allow access for placing and
compacting equipment. The first lift will be compacted by the tracking of heavy
equipment, such as a Caterpillar D6 Dozer (or equivalent), using at least 4
passes, prior to the placement of the next lift. Subsequent lifts will not exceed 12
inches and will be compacted using a minimum of 4 passes with the tracked
equipment or a vibratory compactor.
The CQA technicians will monitor and approve of the final debris placement. In
areas where voids are observed during placement, the contractor shall re-
excavate the area, fill any voids encountered with soil and recompact the
materials, or grout the voids.”
Vessels and tanks will either be crushed (if thin-walled and compressible) or cut open (if
thick-walled and incompressible). Vessels that are to be cut open and filled, will be
placed in the cell such that fill can also be placed around them and compacted. For
thick-walled tanks or vessels that cannot be cut open due to cutting difficulties or worker
health concerns with cutting these items open, these tanks or vessels will be placed in
the designated area of disposal, with interior voids spaces grouted full.

c. Please provide detailed procedures that will be used to control residual voids to meet the
specified maximum allowable void space percentage(s) and a description of the specific
August 15, 2012
Interrogatory 04/1: R313-24-4; 10CFR40.Appendix A, Criterion 4: Void Space Criteria and Debris, Rubble Placement and Soil/Backfill Requirements
Page 14 of 117
construction quality assurance / quality control and verification procedures to be used to
demonstrate that the void space criteria will be achieved.
Response 1(1c) (May 31, 2012 and August 15, 2012):
Quality assurance observation during fill and debris placement must be used to monitor
the occurrence of voids that will require additional material to fill, or additional
compaction of the debris layer. The contractor must ensure that debris is size-reduced to
meet the specifications, so that it can be placed in the cell efficiently and without nesting
or the occurrence of large voids. The Contractor will be required to repetitively attempt
to make passes over the debris and fill voids with soil until the QA staff has determined
that the voids are adequately filled, or an alternate method such as grouting will be
required. The QA staff will make a recommendation to the Contractor for the
implementation of a grouting program in instances when voids, either within a debris
mass, or within a vessel, cannot be properly filled with soil using conventional
equipment.

d. Demonstrate how the percentage of allowable void space relates to the settlement analyses
performed to evaluate the effectiveness of the procedures for placing debris fragments and
rubble, placement of backfill in/around/under debris items, and compaction of the
debris/backfill materials, for precluding the potential for slope reversal in the Cell1 cover
system. Please also refer to “INTERROGATORY WHITEMESA RECPLAN REV. 5.0; R313-
24-4; 10CFR40 APPENDIX A; INT 07/1: TECHNICAL ANALYSIS - SETTLEMENT AND
POTENTIAL FOR COVER SLOPE REVERSAL AND/OR COVER LAYER CRACKING”.
Response 1(1d) (May 31, 2012 and August 15, 2012):
Limiting the percentage of allowable void space within the debris fill will minimize the
resulting settlement caused by the consolidation of the debris mass and the potential for
slope reversal. However, the in-situ void characteristics of debris mass consisting of
concrete and steel of various shapes and sizes, can be difficult to quantify for settlement
analyses. The settlement analyses and any correlation to the percentage of voids within
the debris will be discussed further in responses to that interrogatory.
It should be noted that the cover on top of the disposal cell will not be placed until
settlement monitoring of the subsurface shows that anticipated settlement has taken
place.

e. Please further define the characteristics of, and estimate the percentage of organic materials
(including, for example, wood, branches, roots, paper, and plastic), expected to be disposed
of. Provide specifications and procedures for disposing of organic materials such that long-
term biodegradation of the disposed organic materials will not compromise the integrity and
stability of the cover system.
Response 1(1e) (May 31, 2012 and August 15, 2012):
The percentage of organic materials to be disposed of is anticipated to be a small
percentage of the total material being disposed. Because the quantity of organics for
disposal is minimal and because these materials are likely be mixed with incompressible
debris and soil, the biodegradation of these materials is not anticipated to compromise
the integrity of the cover system. Additionally, the organic materials will be spread
August 15, 2012
Interrogatory 04/1: R313-24-4; 10CFR40.Appendix A, Criterion 4: Void Space Criteria and Debris, Rubble Placement and Soil/Backfill Requirements
Page 15 of 117
throughout the disposal area which will minimize concentrated areas of compressible
organic materials.
Organic debris should be size-reduced by crushing, chipping, or shredding prior to
placement. As described in the Technical Specifications, organic material should only be
placed in lifts less than 12 inches thick and should be mixed with the soil and other
incompressible debris during placement to prevent pockets of organic material from
being created. Organics mixed with soil for spreading should be limited to 30% by
volume of the mixture. This limit will be added to the Technical Specifications.

f. Please provide detailed specifications for segmenting and placing metallic waste materials in
layers so that structural shapes or other large pieces will not lie across or on top of each
other. Please indicate that placement of metallic materials will allow large voids to be
minimized and filled with soil. Please address special handling and disposal procedures for
oversized and/or odd-shaped steel materials, including cutting or trimming dimensions before
positioning for burial, and placement procedures to ensure that no large “slip planes” will
occur within the disposal mass. Specify maximum allowable lift thickness for such material
placement. Please also describe shredding, cutting or trimming procedures required to
ensure that such materials following shredding, cutting or trimming can be placed within the
specified allowable layer thickness.
Response 1(1f) (May 31, 2012 and August 15, 2012):
The Contractor will select and place metallic debris by sizes so that larger pieces are not
stacked on top of each other at angles. Large structural shapes will either be laid edge to
edge so that they can be covered by soil that will fill in open spaces or they must be
spaced far enough apart that equipment can operate between them to compact fill. As
stated in the Technical Specifications, long structural (incompressible) members will be
oriented horizontally. Metallic materials will be size reduced before placement and burial
to a maximum dimension of 20 feet and a maximum volume of 30 cubic feet. Any
metallic materials exceeding the specified dimensions will be cut or trimmed until they
meet this specification.

g. Provide additional details of type of materials and placement practices, including specific
dimensions of all demolition debris expected to be disposed of in Cell 1. Please justify that
items needing to be size-reduced prior to disposal will in fact be size reduced. Provide
additional information to justify that a maximum allowable size of dismantled or cut
materials of 20 feet in the longest dimension (as proposed) and a maximum volume of 30
cubic feet are acceptable criteria for placement of such objects in a disposal cell.
Response 1(1g) (May 31, 2012 and August 15, 2012):
At this time the specific dimensions of all demolition debris expected to be disposed of is
not available. These maximum allowable sizes of cut or dismantled materials have been
specified for demolition of multiple uranium mill sites in the western US. While the
specified maximum dimensions of 30 cubic feet, 20 feet for debris, and 10 feet for pipe,
may be larger than the references cited (DOE, 1995, 2000), typically demolition is sized
for the haulage equipment and often the individual pieces of debris will be less than
these maximum dimensions in order to fit in trucks. Debris objects approaching 20 feet
in length or 30 cubic feet are most likely to be long slender shapes which will have to be
laid flat for disposal, or they are large blocky, or open vessel objects, which will be filled
August 15, 2012
Interrogatory 04/1: R313-24-4; 10CFR40.Appendix A, Criterion 4: Void Space Criteria and Debris, Rubble Placement and Soil/Backfill Requirements
Page 16 of 117
for placement. In either case, it is the method of placement in the cell and controlling the
lift thickness, rather than the dimension of the debris that will determine the potential for
excessive void spaces.
The references cited by the reviewer describe limiting the maximum volume to 27 cubic
feet however only one of the references cited (DOE, 1995) includes a maximum
dimension of 10 feet. The second reference, specifications for Weldon Springs Disposal
Facility (DOE, 2000) does not include a maximum dimension for metal waste or large
metal pieces, it states only that pipe stockpiled “…has been cut to 10 feet or less…”
Based on our experience at other sites, and the review of the cited specifications, the
proposed maximum length of 20 feet falls within the range of maximum lengths specified
by the cited specifications. The proposed specifications include a maximum dimension of
20 feet for all debris and a 10-foot maximum dimension for pipes.

h. Please provide a contingency plan to address the situation in which an insufficient quantity of
demolition debris and rubble and contaminated soil would be available to fill the Cell 1
footprint area to a sufficiently high final waste grading configuration to provide a smooth,
continuous transition between the completed Cell 1 cover system and the Cell 2 cover system,
with no sudden, abrupt changes in slope between the two cover systems. Discuss means and
methods that will be used, regardless of achieved final debris/rubble/contaminated soil
placement grades, for ensuring that a smooth cover slope transition will occur between these
two cell area cover systems.
Response 1(1h) (May 31, 2012 and August 15, 2012):
If sufficient debris, rubble and contaminated soil is not available to fill Cell 1 as designed,
the footprint of Cell 1 can be reduced in size so that the horizontal dimension extending
out from the Cell 2 is reduced and the lateral extent of the disposed materials is reduced
to be closer the base of the Cell 2 impoundment. This would allow the height of the cell
to be maintained and the volume reduced, so that the cover slopes, as designed, will
create a smooth, positive sloping transition from the Cell 2 to Cell 1. While it is unlikely
that the volume of contaminated soil will be insufficient, if additional fill is needed to raise
the elevation above the disposed material, clean fill could be used to establish proper
positive drainage on the cover.

i. Clearly and consistently define procedures/specifications for backfilling of interior void spaces
inside debris objects (e.g., backfill of insides of smaller segmented pipe sections). Rectify
apparent current inconsistencies between descriptions of backfill materials proposed for such
use as described in Attachment A (e.g., controlled low-strength materials [CLSM] or
flowable fill) and backfill materials for this use as described in Appendix (random fill
materials). Provide rationale for selecting preferred backfill materials (e.g., CLSM) for
different types and/or sizes of internal void space, as appropriate. For CLSM/ flowable fill,
etc… used, provide information on the minimum required compressible strength of the
material.
Response 1(1i) (May 31, 2012) and August 15, 2012:
The proposed procedure for filling void spaces, either within vessels, pipes that cannot
be crushed (with a diameter of larger than 12 inches), or other miscellaneous voids, is to
first attempt to fill the voids with soil. This would be done in the case of vessels by either
placing soil through an existing opening, or cutting them open so that soil can be placed
August 15, 2012
Interrogatory 04/1: R313-24-4; 10CFR40.Appendix A, Criterion 4: Void Space Criteria and Debris, Rubble Placement and Soil/Backfill Requirements
Page 17 of 117
using the bucket of an excavator. Pipe sections, that cannot be crushed flat, can be cut
short enough to stand on their ends, and then filled with soil from the bucket of an
excavator.
To rectify the discrepancy between Attachment A and Appendix G, the language in the
specification Section 7.3.6 of the Technical Specifications will be modified as follows:
“The voids on the inside of the item shall be filled with contaminated soil, clean fill
soil, or grout (controlled low-strength material, flowable fill, etc.). Contaminated
soil (Section 7.3.3) or clean fill will be placed outside of the items and compacted
with standard compaction equipment (where possible) or hand-operated
equipment to the compaction requirements in Specification Section 7.4.”
For debris where internal voids cannot practically be filled with soil, a grouting program
would be initiated to pump controlled low strength material (CLSM, flowable fill) into the
voids. Debris would be grouped together and characterized as materials that would
require grouting, so that a significant volume of debris can be grouted in a single action,
rather than grouting individual lengths of pipe. Pipe sections could be stacked
horizontally, or cut short enough to stand vertically in a safe manner. Grout would then
likely be batched offsite and delivered to the site and a pump truck would likely be
required to place the material within the debris, within the cell. A soil berm would be
used to contain the grout laterally around the perimeter of the selected debris. The
debris voids would be grouted, and grout would also be placed around the debris to
develop a monolithic grouted mass.
The specified unconfined compressive strength of the CLSM would be between 30 psi
(minimum) and 150 psi (maximum). Unit weights on the order of 100 to 120 pcf will be
specified. These requirements will be added to the specifications.

j. Describe how the compressive strength requirement for CLSM or other grout backfill, in
conjunction with the void space backfilling requirements and ultimate allowable void space
and organic waste percentages relate to the design objectives for minimizing settlement of the
backfilled Cell 1 area debris/rubble/backfill mass to preclude the possibility for long-term
cover slope reversals.
Response 1(1j) (May 31, 2012 and August 15, 2012):
If CLSM is required for the grouting of voids that cannot be filled mechanically with soil,
the mix design for the grout should mimic, as closely as possible, the strength and
hydraulic properties of the contaminated soil that will also be used for filling voids within
the debris. This will minimize any effects of differential settlement that would result from
the grout having a higher strength and being less compressible than the surrounding
soil.

BASIS FOR INTERROGATORY:
The placement of debris materials in the reclaimed tailings embankment has the potential to create voids
or areas of insufficient compaction. The presence of excessive voids in the final reclaimed waste disposal
embankment following waste placement and construction of the final closure cover could lead to
unacceptable amounts of long-term total or differential settlement in the reclaimed embankment.
Excessive amounts of such settlement could impact the integrity of the final closure cover system, and, if
sufficient in extent, result in localized slope change(s) and/or slope reversal(s) in the final slopes of the
August 15, 2012
Interrogatory 04/1: R313-24-4; 10CFR40.Appendix A, Criterion 4: Void Space Criteria and Debris, Rubble Placement and Soil/Backfill Requirements
Page 18 of 117
reclaimed embankment. A slope reversal would create an opportunity for localized ponding of moisture
or water which could result in increased infiltration rates through the embankment. To address/mitigate
potential concerns relating to settlement following waste placement, procedures for placing and
compacting soil and debris wastes should incorporate several requirements, including specifying a
method or methods for filling of larger-sized void spaces (e.g., with CLSM/flowable fill or other grout,
etc…) that cannot be readily accessed by standard construction equipment for backfilling with soil or
tailings.
Appendix G to the Reclamation Plan Rev. 5.0 states “Contaminated soils will be disposed of in last active
tailings cell or Cell 1. Contaminated soils will be placed in the last active cell or Cell 1 as random fill
material (material used to fill voids within mill material, achieve desired cover system slopes, and
provide a firm base for construction of the cover system)”. In contrast, Attachment A to the Reclamation
Plan Rev. 5.0 states “…The voids on the inside of the item shall be filled with sand or grout (controlled
low-strength material, flowable fill, etc.)”. Clarification needs to be made on which method/methods will
be used for filling larger-sized void spaces.
It is recommended that if the void space resulting from placement of such large concrete monoliths is
greater than approximately 5%, then an acceptable cement grout or flowable fill such as controlled low-
strength material be placed between the monoliths, or alternativelythat monoliths be placed far enough
apart to allow proper equipment access to compact as necessary.
Attachment A to the Reclamation Plan Rev. 5 states that “the maximum size of dismantled or cut
materials shall not exceed 20 feet in the longest dimension and a maximum volume of 30 cubic feet for
placement in the cells”. Additional justification needs to be provided to demonstrate that these
dimensions will be adequate for disposal with respect to minimizing potential for differential settlement
occurring within the disposal cell. For other similar projects (e.g., DOE 1995; DOE 2000), based on
experience gained at several uranium mill demolition debris and rubble disposal projects, specified the
following procedures for placing and compacting soil and debris and rubble wastes into tailings
repositories to address/mitigate potential concerns relating to settlement:
• Limiting the maximum dimension of larger-sized debris items to a maximum allowable length
(e.g., 10 ft) in longest dimension;
• Limiting at least one dimension of larger-sized debris items to no more than a maximum
allowable width (e.g., 10 to 12 inches for pipes); and
• Specifying a method or methods for filling of larger-sized void spaces (e.g., with flowable fill or
grout) that cannot be readily accessed by standard construction equipment for backfilling with
soil or tailings.
To accomplish the above objectives, it was specified that larger sized items be placed as flatly as possible
rather than in a tangled mass that could result in “nesting”, i.e., result in a compressible mass that would
be subject to excessive compression as additional fill is placed and compacted. For these projects,
individual loads of larger sized items were also specified to be spread out as necessary to ensure proper
filling of any open voids with contaminated soil or tailings and so that contaminated soil or tailings
backfill materials and the debris items could be adequately compacted.
Additionally, these projects included specifications that window frames, siding, and roofing material be
placed and compacted, at a minimum, as pieces or stacks of such materials (e.g., bundles of siding) in an
18-inch lift, occasionally increased to 24 inches for taller bundles of wood pieces; that placement be
accomplished in a compact, dense layer with bundles placed next to each other to the extent possible, that
voids between bundles be reduced to the minimum achievable, and that bundles that are broken be
separated into stacks 12 inches or less in height; and that contaminated soil or tailings then be spread
and compacted over the layer not exceeding 12-inches in loose lift thickness.
August 15, 2012
Interrogatory 04/1: R313-24-4; 10CFR40.Appendix A, Criterion 4: Void Space Criteria and Debris, Rubble Placement and Soil/Backfill Requirements
Page 19 of 117
Similar sets of detailed specifications were developed and used on the above-described projects for size-
reduction and controlled placement of pipe sections, concrete rubble, monoliths, and large rock
fragments, and associated backfill placement, and compaction of debris/rubble and soil mixtures.
The applicability and benefit of employing these specifications or similarly detailed specifications, should
be evaluated, and implemented for this project as warranted.

REFERENCES:
Denison Mines (USA) Corporation. 2011. Reclamation Plan, Revision5.0, White Mesa Mill, Blanding,
Utah: September 2011
Denison Mines (USA) Corporation. 2009a. Reclamation Plan, Revision 4.0, White Mesa Mill, Blanding,
Utah, Exhibit C: November 2009
Exhibit C: Probable Maximum Precipitation (PMP) Event Computation, White Mesa Mill - Cell 4B,
Blanding , Utah”. September 10, 2009. Letter to Dane Finerfrock, dated September 11, 2009.
DOE (U.S. Department of Energy). 1989. Technical Approach Document, Revision II. UMTRA-DOE/AL
050425.0002.
DOE 1995. Uranium Mill Tailings Remedial Action Project, Slick Rock, Colorado Subcontract
Documents. U.S. Department of Energy, Albuquerque, New Mexico. October 1, 1995. DOE/AL/62350—
21F-Rev. 1-Attachment.
DOE 2000. WSSRAP Disposal Facility Technical Specifications, Section 2300: Waste Removal,
Handling, and Placement. WP-437, Disposal Cell Construction. May 15, 2000.
EPA (U.S. Environmental Protection Agency). 1989a. Final Covers on Hazardous Waste Landfills and
Surface Impoundments, Technical Guidance Document, EPA/530-SW-89-047, Office of Solid Waste and
Emergency Response, Washington, D.C. URL:
http://webcache.googleusercontent.com/search?q=cache:VEVCaJfyPDQJ:nepis.epa.gov/Exe/ZyPURL.cg
i%3FDockey%3D100019HC.txt+site:epa.gov+EPA+Final+Covers+Guidance&cd=4&hl=en&ct=clnk
&gl=us.
EPA 1991. Seminar Publication, Design and Construction of RCRA/CERCLA Final Covers. EPA/625/4-
91/025.May 1991, 208 pp.
EPA 2004. (Draft) Technical Guidance for RCRA/CERCLA Final Covers. U.S EPA 540-R-04-007,
OSWER 9283.1-26. April 2004, 421 pp. URL: nepis.epa.gov/Exe/ZyPURL.cgi?Dockey=P10074PP.txt.
Gilbert, P.A., and Murphy, W.M. 1987. Prediction/Mitigation of Subsidence Damage to Hazardous Waste
Landfill Covers.EPA/600/2-87/025, March 1987, 81 pp. NTIS PB-175386.
Nelson, J.D., Abt, S.R., Volpe, R.L, van Zyl, D., Hinkle, N.E., and Staub, W.P. 1986. Methodologies for
Evaluating Long-Term Stabilization Designs of Uranium Mill Tailings Impoundments. Prepared for
Nuclear Regulatory Commission, Washington, DC.NUREG/CR-4620, ORNL/TM-10067.June 1986, 151
pp.
NRC 2002. U.S. Nuclear Regulatory Commission, “Design of Erosion Protection for Long-Term
Stability”, NUREG-1623, September 2002.
August 15, 2012
Interrogatory 04/1: R313-24-4; 10CFR40.Appendix A, Criterion 4: Void Space Criteria and Debris, Rubble Placement and Soil/Backfill Requirements
Page 20 of 117
NRC 2003. Standard Review Plan for the Review of a Reclamation Plan for Mill Tailings Sites under
Title II of the Uranium Mill Tailings Radiation Control Act of 1978. Washington DC, June 2003.
August 15, 2012
Interrogatory 05/1: R313-24-4; 10CFR40.Appendix A: Seismic Hazard Evaluation Page 21 of 117
INTERROGATORY WHITEMESA RECPLAN REV. 5.0 R313-24-4, 10 CFR 40 APPENDIX A;
INT 05/1: SEISMIC HAZARD EVALUATION
REGULATORY BASIS:
UAC R313-24-4 invokes the following requirement from 10CFR40, Appendix A, Criterion 1: “ The general
goal or broad objective in siting and design decisions is permanent isolation of tailings and associated
contaminants by minimizing disturbance and dispersion by natural forces, and to do so without ongoing
maintenance. For practical reasons, specific siting decisions and design standards must involve finite
times (e.g., the longevity design standard in Criterion 6).
Refer to R313-24-4, 10 CFR 40 Appendix A, Criterion 4 (e): The impoundment may not be located near a
capable fault that could cause a maximum credible earthquake larger than that which the impoundment
could reasonably be expected to withstand. As used in this criterion, the term “capable fault” has the
same meaning as defined in section III(g) of Appendix A of 10 CFR Part 100. The term “maximum
credible earthquake” means that earthquake which would cause the maximum vibratory ground motion
based upon an evaluation of earthquake potential considering the regional and local geology and
seismology and specific characteristics of local subsurface material.
UAC R313-24-4 invokes the following requirement from 10CFR40, Appendix A, Criterion 6(1): “In
disposing of waste byproduct material, licensees shall place an earthen cover (or approved alternative)
over tailings or wastes at the end of milling operations and shall close the waste disposal area in
accordance with a design which provides reasonable assurance of control of radiological hazards to (i)
be effective for 1,000 years, to the extent reasonably achievable, and, in any case, for at least 200 years,
and (ii) limit releases of radon-222 from uranium byproduct materials, and radon-220 from thorium
byproduct materials, to the atmosphere so as not to exceed an average release rate of 20 picocuries per
square meter per second (pCi/m2s) to the extent practicable throughout the effective design life
determined pursuant to (1)(i) of this criterion. In computing required tailings cover thicknesses, moisture
in soils in excess of amounts found normally in similar soils in similar circumstances may not be
considered. Direct gamma exposure from the tailings or wastes should be reduced to background levels.
The effects of any thin synthetic layer may not be taken into account in determining the calculated radon
exhalation level. If non-soil materials are proposed as cover materials, it must be demonstrated that these
materials will not crack or degrade by differential settlement, weathering, or other mechanism, over long-
term intervals.”
NUREG-1620 specifies that “Reasonable assurance [shall be] provided that the requirements of 10 CFR
Part 40, Appendix A, Criterion 6(1), which requires that the design of the disposal facility provide
reasonable assurance of control of radiological hazards to be effective for 1,000 years, to the extent
reasonably achievable, and, in any case, for at least 200 years, have been met.”

INTERROGATORY STATEMENT:
Refer to Appendix E and Attachment E.1 to Appendix E to Appendix D, Updated Tailings Cover
Design Report of the Reclamation Plan, Rev. 5: Please provide the following:
1. Please further clarify the rationale for selecting the annual probability of exceedance of hazard
for the facility.
Response 1 (May 31, 2012 and August 15, 2012): Previous seismic hazard analyses
for the site evaluated peak ground acceleration (PGA) at the site for the operational life
(MFG, 2006) and long-term reclaimed conditions (Tetra Tech, Inc. (Tetra Tech), 2010).
The seismic hazard analysis by MFG (2006) compared the results of a deterministic
seismic hazard analysis (DSHA) to USGS National Seismic Hazard Maps showing the
August 15, 2012
Interrogatory 05/1: R313-24-4; 10CFR40.Appendix A: Seismic Hazard Evaluation Page 22 of 117
peak ground acceleration (PGA) associated with a 2 percent probability of exceedance
in 50 years, or a return period of 2,475 years. The projected operational lifetime of the
most recently constructed tailings cell at the site is estimated to be approximately 50
years, from the time of construction through the time when the cell will have been
dewatered and reclaimed. Therefore, use off a 2,475-year return period in formulating
the probabilistic operational design criteria is considered conservative as this event has
a 2-percent probability of exceedance over the anticipated 50-year operational design
life.
The seismic hazard analysis by Tetra Tech (2010) evaluated the PGA for long-term site
conditions. Tetra Tech conducted a deterministic seismic hazard analysis and
compared the results with the PGA associated with a 2 percent probability of
exceedance during a 200-year design life, based on the USGS 2008 National Seismic
Hazard Mapping Program (NSHMP) PSHA Interactive Deaggregation data. Two
percent probability of exceedance during a 200-year period is equivalent to a return
period of 9,900 years. The U.S. Environmental Protection Agency (EPA) Standards for
the Control of Residual Radioactive Materials from Inactive Uranium Processing Sites
(40 CFR 192) and the NRC Criteria Relating to the Operation of Uranium Mills and the
Disposition of Tailings or Wastes Produced by the Extraction or Concentration of Source
Material From Ores Processed Primarily for Their Source Material Content (NRC 10
CFR Appendix A to Part 100 A) both specify that control of residual radioactive material
must be effective for up to 1,000 years to the extent reasonably achievable, and for at
least 200 years. Use of a 9,900-year return period in formulating the probabilistic design
criteria for reclaimed conditions is considered conservative as this event has a 2 percent
probability of exceedance during a 200-year period and a less than 10 percent
probability of exceedance in a 1,000-year period.
A site-specific probabilistic seismic hazard analysis (PSHA) for both operational
conditions and long-term reclaimed conditions has been performed for the site. The
results of the analysis are discussed in Response 5.

References for Response 1 (May 31, 2012 and August 15, 2012):
MFG, Inc. (MFG), 2006. White Mesa Uranium Facility, Cell 4 Seismic Study, Blanding,
Utah. November 27.

Tetra Tech, Inc (Tetra Tech), 2010. Technical Memorandum: White Mesa Uranium
Facility, Seismic Study Update for a Proposed Cell, Blanding Utah. February 3.

2. Adjust the cited USGS National Hazard Map PGA (peak ground acceleration) value of 0.15 g for
the site Vs30 as appropriate.
Response 2 (May 31, 2012 and August 15, 2012): The site Vs30 was calculated by
Tetra Tech (2010) for the uppermost 100 feet of soil and bedrock underlying the site.
The site-specific Vs30 was determined to be 586 m/s. This seismic velocity correlates to
materials characterized as Site Class E – Soft Soil, by both the International Building
Code (IBC) and the National Earthquake Hazard Reduction Program (NEHRP).
Denison’s consultant MWH Americas, Inc. (MWH) checked Tetra Tech’s calculation of
Vs for the uppermost 100 feet of soils and bedrock underlying the site. The drilling logs
by Tetra Tech (2010) and Dames and Moore (1978) were used to obtain information
August 15, 2012
Interrogatory 05/1: R313-24-4; 10CFR40.Appendix A: Seismic Hazard Evaluation Page 23 of 117
about the subsurface conditions at the site (Standard Penetration Test (SPT) blow
counts, bedrock descriptions, and depths of auger drilling versus coring) and to calculate
values of Vs for the soils and estimate values of Vs30 for the underlying bedrock
materials.
The average value of SPT blow counts for the silty sand and soil material encountered in
the top 30 feet of the Tetra Tech boring is 58.6 (Tetra Tech, 2010). Using information in
Sykora (1987) (eqs.20, 21 and Table 4 eq. 8) values of Vs30 were calculated to range
from approximately 660 feet/second (ft/s) to 990 ft/s (approximately 200 to 300
meters/second (m/s)). This is also consistent with information presented in Fig. 5, Fig. 6,
Fig. 10, and Table 8 of Sykora (1987). Based on the bedrock descriptions presented in
the drilling logs by Dames and Moore (1978) to a maximum depth of 140 feet, the
estimated seismic velocity for the remaining 70 feet of generally well-cemented
sandstone with minor interbedded claystone, siltstone and conglomerate, is estimated to
range from 800 to 1,000 m/s. A weighted average of seismic velocity for the upper 100
feet below the site was calculated to range from approximately 620 m/s to 700 m/s. This
seismic velocity correlates with materials characterized as Site Class D – Stiff Soil by
both the IBC and NEHRP.
The NSHMP 2008 PSHA Interactive Deaggregation web site used by Tetra Tech to
calculate the PGA for the site limits input values of Vs30 to either 760 m/s or 2,000 m/s.
These seismic velocities correspond to Site Class BC (intermediate between dense soil
and rock) and Site Class A (hard rock), respectively. Although the text that accompanies
the PSHA program states that site-specific values of Vs30 can be input for sites in the
Western US, the White Mesa site is considered to be located within the Central/Eastern,
United States for the program (Martinez, 2012), and input values for Vs30 are limited to
760 m/s or 2,000 m/s. The available input value of Vs30 of 760 m/s is appropriate for
the site-specific analysis based on the range of seismic velocity estimated for the site.

References for Response 2 (May 31, 2012 and August 15, 2012):

Dames and Moore, 1978. Site Selection and Design Study - Tailing Retention and Mill
Facilities, White Mesa Uranium Project. January 17.

Martinez, E., 2012. Electronic communication from E. Martinez, U.S. Geological
Survey, to E. Dornfest, MWH Americas, Inc., regarding 2008 deaggregations
web site bug, May 16.

Sykora, D.W., 1987. Examination of Existing Shear Wave Velocity and Shear Modulus
Correlations in Soils. U.S. Army Corps of Engineers Miscellaneous Paper GL-
87-22. September.

Tetra Tech, Inc (Tetra Tech), 2010. Technical Memorandum: White Mesa Uranium
Facility, Seismic Study Update for a Proposed Cell, Blanding Utah. February 3.

3. Explain why the calculated hazard for the background earthquake PGA of 0.24 g was estimated
but ignored in the recommendations provided in Appendix E.
August 15, 2012
Interrogatory 05/1: R313-24-4; 10CFR40.Appendix A: Seismic Hazard Evaluation Page 24 of 117
Response 3 (May 31, 2012 and August 15, 2012): Evaluation of the PGA due to a
background earthquake unassociated with a known structure is typically included as a
portion of a deterministic seismic hazard analysis. The analysis includes evaluating the
potential for low to moderate earthquakes unassociated with tectonic structures to
contribute to the seismic hazard of the site. The seismic hazard analysis performed by
Tetra Tech included an evaluation of a background earthquake because it was a
deterministic analysis. However, in order to evaluate the contribution from a background
event in a deterministic analysis, one must estimate a likely magnitude and distance
from the site. Tetra Tech (2010) estimated a magnitude 6.3 event consistent with that
used in previous seismic evaluations performed for sites in the Colorado plateau, and
cited in their report. The 15km distance to a background earthquake was chosen as a
distance which would provide a conservative PGA at the site.
The total seismic hazard at a site is better quantified by performing a probabilistic
seismic hazard analysis to determine the likelihood of a specific ground acceleration
occurring at the site within a given time frame (operational or reclaimed design life). A
site-specific PSHA has been performed for the site. The results of the analysis are
discussed in Response 5.

References for Response 3 (May 31, 2012 and August 15, 2012):
Dames and Moore, 1978. Site Selection and Design Study - Tailing Retention and Mill
Facilities, White Mesa Uranium Project. January 17.

Tetra Tech, Inc (Tetra Tech), 2010. Technical Memorandum: White Mesa Uranium
Facility, Seismic Study Update for a Proposed Cell, Blanding Utah. February 3.

4. Provide information to justify the use of 15 km distance for a background earthquake Mw 6.3
event.
Response 4 (May 31, 2012 and August 15, 2012): See Response 3.

5. Perform and report results of a site-specific probabilistic seismic analysis in lieu of using the
USGS National Hazard Maps for developing site-specific seismic design parameters.
Response 5 (May 31, 2012 and August 15, 2012):
Denison’s consultant MWH performed a site-specific PSHA for the Site. The PGA
associated with a 2 percent probability of exceedance in 50 years, calculated for the
operational lifetime of the facility, is 0.07g. The PGA associated with a 2 percent
probability of exceedance in 200 years, calculated for the long-term reclaimed site
conditions, is 0.15g. The details of the analysis are presented in Attachment A of the
previous response document (Denison, 2012).

References for Response 4 (August 15, 2012):
Denison Mines (USA) Corp. (Denison), 2012. Responses to Interrogatories – Round 1
for Reclamation Plan, Revision 5.0, March 12. May 31.

August 15, 2012
Interrogatory 05/1: R313-24-4; 10CFR40.Appendix A: Seismic Hazard Evaluation Page 25 of 117

BASIS FOR INTERROGATORY:
The rationale for selecting the annual probability of exceedance of hazard for the facility needs to be
clarified. Appendix E to the Appendix D of the Reclamation Plan Rev. 5 states that the “10,000 year
return period (1 in 10,000 annual probability) is adopted for evaluating the long-term stability of the
facility”. However, in the following sentences, the report states that a return period of 2,500 years (1 in
2500 annual probability) is appropriate for the operational conditions of the facility. It needs to be
clarified if or how the facility is being evaluated for the two annual probabilities. Is so, further details
would need to be provided.
It is unclear how the 0.15 g PGA is “reasonable for the White Mesa site”. Appendix E cites the USGS
National Hazard Maps and a PGA of 0.15 g for a 10,000 year return period. This value is for a Vs30 of
760 m/sec. The report continues by stating that the Vs30 for the site is 586 m/sec. The 0.15 g value cited
in this regard needs to be adjusted for the site Vs30.
Appendix E describes background earthquakes and adopts an Mw 6.3 event at a distance of 15 km.
Additional justification needs to be provided for the use of the 15 km distance.
A single ground motion prediction model should not be used in hazard analysis because the epistemic
uncertainty in ground motion prediction is being ignored. Currently, there are five Next Generation
Attenuation (NGA) ground motion models, including an update of Campbell and Bozorgnia (2007), which
should be used in the deterministic calculation for the PGAs in Table 1, Peak Ground Accelerations for
White Mesa, in Attachment E.1 of Appendix E.
The USGS National Hazard Maps should not be used for developing site-specific seismic design
parameters (Personal Communication between Dr. Mark Petersen, Chief, National Seismic Hazard
Mapping Project, and Ivan Wong of URS Corporation 2010) for critical and important facilities. For
such types of facilities, a site-specific probabilistic seismic hazard analysis is recommended.

REFERENCES:
Campbell, K.W. and Bozorgnia, Y., 2007, Campbell-Bozorgnia NGA Ground motion relations for the
geometric mean horizontal component of PGA, PGV, PGD and 5% Damped Linear Elastic Response
Spectra for Periods Ranging from 0.01 to 10 s: Earthquake Spectra 24, pp. 139-171. 2008
Denison Mines (USA) Corp., 2011. Reclamation Plan, White Mesa Mill, Blanding, Utah, Radioactive
Materials License No. UT1900479, Revision 5.0, Appendix E, September 2011.
August 15, 2012
Interrogatory 06/1: R313-24-4; 10CFR40.Appendix A, Criterion 1: Slope Stability Page 26 of 117
INTERROGATORY WHITEMESA RECPLAN REV5.0; R313-24-4; 10CFR40 APPENDIX A,
CRITERION 1; INT 06/1: SLOPE STABILITY
REGULATORY BASIS:
UAC R313-24-4 invokes the following requirement from 10CFR40 Appendix A, Criterion 1: The general
goal or broad objective in siting and design decisions is permanent isolation of tailings and associated
contaminants by minimizing disturbance and dispersion by natural forces, and to do so without ongoing
maintenance. For practical reasons, specific siting decisions and design standards must involve finite
times (e.g., the longevity design standard in Criterion 6). . . .
Refer also to INTERROGATORY WHITEMESA RECPLAN Rev. 5.0 R313-24-4, 10 CFR 40 APPENDIX
A; INT 05/1: SEISMIC HAZARD EVALUATION above.
Slope Stability
NUREG-1620, Section 2.2.3: The analysis of slope stability will be acceptable if it meets the
following criteria:
(1) Slope characteristics are properly evaluated.
(a) Cross sections and profiles of natural and cut slopes whose instability would directly or
indirectly affect the control of radioactive materials are presented in sufficient number and detail
to enable the reviewer to select the cross sections for detailed stability evaluation.
(b) Slope steepness is a minimum of five horizontal units (5h) to one vertical unit (1v) or less. The
use of slopes steeper than 5h:1v is considered an alternative to the requirements in 10 CFR Part
40, Appendix A, Criterion 4(c). When slopes steeper than 5h:1v are proposed, a technical
justification should be offered as to why a 5h:1v or flatter slope would be impractical and
compensating factors and conditions are incorporated in the slope design for assuring long-term
stability.
(c) Locations selected for slope stability analysis are determined considering the location of
maximum slope angle, slope height, weak foundation, piezometric level(s), the extent of rock mass
fracturing (for an excavated slope in rock), and the potential for local erosion.
(2) An appropriate design static analysis is presented.
(a) The analysis includes calculations with appropriate assumptions and methods of analysis (NRC,
1977). The effect of the assumptions and limitations of the methods used is discussed and accounted
for in the analysis. Acceptable methods for slope stability analysis include various limit equilibrium
analysis or numerical modeling methods.
(b) The uncertainties and variability in the shape of the slope, the boundaries and parameters of the
several types of soils and rocks within and beneath the slope, the material properties of soil and rock
within and beneath the slope, the forces acting on the slope, and the pore pressures acting within and
beneath the slope are considered.
(c) Appropriate failure modes during and after construction and the failure surface corresponding to
the lowest factor of safety are determined. The analysis takes into account the failure surfaces within
the slopes, including through the foundation, if any.
(d) Adverse conditions such as high water levels from severe rain and the probable maximum flood
are evaluated.
(e) The effects of toe erosion, incision at the base of the slope, and other deleterious effects of surface
runoff are assessed.
August 15, 2012
Interrogatory 06/1: R313-24-4; 10CFR40.Appendix A, Criterion 1: Slope Stability Page 27 of 117
(f) The resulting safety factors for slopes analyzed are comparable to the minimum acceptable values
of safety factors for slope stability analysis given in NRC Regulatory Guide 3.11 . . . .
(3) Appropriate analyses considering the effect of seismic ground motions on slope stability are
presented.
(a) Evaluation of overall seismic stability, using pseudostatic analysis or dynamic analysis, as
appropriate (U.S. Army Corps of Engineers, 1977; NRC, 1977). Alternatively, a dynamic analysis
following Newmark (1965) can be carried out to establish that the permanent deformation of the
disposal cell from the design seismic event will not be detrimental to the disposal cell. The reviewer
should verify that the yield acceleration or pseudostatic horizontal yield coefficient necessary to
reduce the factor of safety against slippage of a potential sliding mass to 1.0 in a “Newmark-type”
analysis has been adequately estimated (Seed and Bonaparte, 1992).
(b) An appropriate analytical method has been used. A number of different methods of analysis are
available (e.g., slip circle method, method of slices, and wedge analysis) with several variants of
each (Lambe and Whitman, 1979; U.S. Army Corps of Engineers, 1970b; NRC, 1977; Bromhead,
1992). Limit-equilibrium analysis methods do not provide information regarding the variation of
strain within the slope and along the slip surface. Consequently, there is no assurance that the peak
strength values used in the analysis can be mobilized simultaneously along the entire slip surface
unless the material shows ductile behavior (Duncan, 1992). Residual strength values should be
evaluated if mobilized shear strength at some points is less than the peak strength. The reviewer
should ensure that appropriate conservatism has been incorporated in the analysis using the limit
equilibrium methods. The limit equilibrium analysis methodologies may be replaced by other
techniques, such as finite element or finite difference methods. If any important interaction effects
cannot be included in an analysis, the reviewer must determine that such effects have been treated in
an approximate but conservative fashion. The engineering judgment of the reviewer should be used
in assessing the adequacy of the resulting safety factors (NRC, 1983a,b).
(c) For dynamic loads, the dynamic analysis includes calculations with appropriate assumptions and
methods (NRC, 1977; Seed, 1967; Lowe, 1967; Department of the Navy, 1982a,b,c; U.S. Army
Corps of Engineers, 1970a,b, 1971, 1972; Bureau of Reclamation, 1968). The effect of the
assumptions and limitations of the methods used is discussed and accounted for in the analysis.
(d) For dynamic loads, a pseudostatic analysis is acceptable in lieu of dynamic analysis if the
strength parameters used in the analysis are conservative, the materials are not subject to significant
loss of strength and development of high pore pressures under dynamic loads, the design seismic
coefficient is 0.20 or less, and the resulting minimum factor of safety suggests an adequate margin,
as provided in NRC Regulatory Guide 3.11 (NRC, 1977).
(e) For pseudostatic analysis of slopes subjected to earthquake loads, an assumption is made that the
earthquake imparts additional horizontal force acting in the direction of the potential failure (U.S.
Army Corps of Engineers, 1970b, 1977; Goodman, 1989). The critical failure surface obtained in the
static analysis is used in this analysis with the added driving force. Minimum acceptable values for
safety factors of slope stability analysis are given in Regulatory Guide 3.11 (NRC, 1977).
(f) The assessment of the dynamic stability considers an appropriate design level seismic event
and/or strong ground motion acceleration, consistent with that identified in Chapter 1 of this review
plan. Influence of local site conditions on the ground motions associated with the design level event
is evaluated. The design seismic coefficient to be used in the pseudostatic analysis is either 67
percent of the peak ground acceleration at the foundation level of the tailings piles for the site or
0.1g, whichever is greater.
August 15, 2012
Interrogatory 06/1: R313-24-4; 10CFR40.Appendix A, Criterion 1: Slope Stability Page 28 of 117
(g) If the design seismic coefficient is greater than 0.20g, then the dynamic stability investigation
(Newmark, 1965) should be augmented by other appropriate methods (i.e., finite element method),
depending on specific site conditions.
(h) In assessing the effects of seismic loads on slope stability, the effect of dynamic stresses of the
design earthquake on soil strength parameters is accounted for. As in a static analysis, the
parameters such as geometry, soil strength, and hydrodynamic and pore pressure forces are varied
in the analysis to show that there is an adequate margin of safety.
(i) Seismically induced displacement is calculated and documented. There is no universally accepted
magnitude of seismically induced displacement for determining acceptable performance of the
disposal cell (Seed and Bonaparte, 1992; Goodman and Seed, 1966). Surveys of five major
geotechnical consulting firms by Seed and Bonaparte (1992) indicate that the acceptable
displacement is from 15 to 30 cm [6 to 12 in.] for tailings piles. The reviewer should ensure that this
criterion is also augmented by provisions for periodic maintenance of the slope(s).
(j) Where there is potential for liquefaction, changes in pore pressure from cyclic loading are
considered in the analysis to assess the effect of pore pressure increase on the stress-strain
characteristics of the soil and the post-earthquake stability of the slopes. Liquefaction potential is
reviewed using Section 2.4 of this review plan. Evaluations of dynamic properties and shear
strengths for the tailings, underlying foundation material, radon barrier cover, and base liner system
are based on representative materials properties obtained through appropriate field and laboratory
tests (NRC, 1978, 1979).
(k) The applicant has demonstrated that impoundments will not be located near a capable fault on
which a maximum credible earthquake larger than that which the impoundment could reasonably be
expected to withstand might occur.
(4) Provision is made to establish a vegetative cover, or other erosion prevention, to include the
following considerations:
(a) The vegetative cover and its primary functions are described in detail. This determination should
be made with respect to any effect the vegetative cover may have on reducing slope erosion and
should be coordinated with the reviewer of standard review plan Chapter 3. If strength enhancement
from the vegetative cover is taken into account, the methodology should be appropriate (Wu, 1984).
(b) In arid and semi-arid regions, where a vegetative cover is deemed not self-sustaining, a rock
cover is employed on slopes of the mill tailings. If credit is taken for strength enhancement from rock
cover, the reviewer should confirm that appropriate methodology has been presented. The design of
a rock cover, where a self-sustaining vegetative cover is not practical, is based on standard
engineering practice. Standard review plan Chapter 3 discusses this item in detail.
(5) Any dams meet the requirements of the dam safety program if the application demonstrates the
following:
(a) The dam is correctly categorized as a low hazard potential or a high hazard potential structure
using the definition of the U.S. Federal Emergency Management Agency;(b) If the dam is ranked as
a high hazard potential, an acceptable emergency action plan consistent with the Federal
Emergency Management Agency guide (U.S. Federal Emergency Management Agency, 1998) has
been developed.
(6) The use of steeper slopes as an alternative to the requirements in 10 CFR, Part 40, Appendix A,
will be found acceptable if the following are met:
(a) An equivalent level of stabilization and containment and protection of public health, safety, and
the environment is achieved.
August 15, 2012
Interrogatory 06/1: R313-24-4; 10CFR40.Appendix A, Criterion 1: Slope Stability Page 29 of 117
(b) A site-specific need for the alternate slopes is demonstrated.
INTERROGATORY STATEMENT:
1. Demonstrate slope stability for the tailings impoundment and new cover system using shear
strength parameters and other soil properties assigned to the various components (cover,
embankment/dike, tailings, and foundation) consistent with soil type, degree of compaction, and
anticipated degree of variability. Justify selection of values for soil parameters.
Response 1 (August 15, 2012):
This response supersedes the response provided in the May 31, 2012 submittal.
A site investigation to further evaluate cover borrow materials was conducted on April
19, 2012. Laboratory results for samples collected were used to develop updated cover
material parameters for slope stability analyses. The results of the updated analyses are
provided in Attachment D as a revised Appendix E, Slope Stability Analysis, of the
Updated Tailings Cover Design Report (Appendix D of the Reclamation Plan, Revision
5.0). Justification of the parameters used in the analyses is provided in Attachment D.

2. In evaluating slope stability, address and report the effects of shallow and non-circular failure
surfaces, in addition to circular and/or deeper ones.
Response 2 (August 15, 2012):
This response supersedes the response provided in the May 31, 2012 submittal.
See Response 1. The stability analyses were revised to include evaluation of shallow
and non-circular failures.

3. Demonstrate that assumed drainage conditions are appropriate, are at least consistent with, or
are conservative compared with drainage/seepage results, projected immediately at closure and
at the end of the impoundment design life (i.e., 1,000 years, to the extent reasonably achievable,
and, in any case, for at least 200 years).
Response 3 (August 15, 2012):
This response supersedes the response provided in the May 31, 2012 submittal.
See Response 1. The phreatic conditions used for the revised stability analyses are
consistent with regards to the tailings dewatering analyses.

4. Assess the slope stability of Cell 1 adjacent to Cell 2 where mill debris and contaminated soils
are to be placed and covered.
Response 4 (August 15, 2012):
This response supersedes the response provided in the May 31, 2012 submittal.
See Response 1. The revised stability analyses include evaluation of the stability of the
Cell 1 Disposal Area embankment.

August 15, 2012
Interrogatory 06/1: R313-24-4; 10CFR40.Appendix A, Criterion 1: Slope Stability Page 30 of 117
5. Explain and justify the selection of the pseudo-static coefficient used in the assessment of seismic
stability. If the selected value of the pseudo-static coefficient cannot be justified, revise the value
of the coefficient used in stability analyses and revise and report the results of stability analyses.
Response 5 (August 15, 2012):
This response supersedes the response provided in the May 31, 2012 submittal.
An update to the previous seismic study for the site has been conducted and was
included as Attachment A of the previous response submittal (Denison, 2012). The
pseudo-static coefficient is estimated as 0.10 corresponding to 2/3 of the Peak Ground
Acceleration (PGA) presented in the Attachment A of Denison (2012). This pseudo-
static coefficient was used for the revised slope stability analyses.

References for Response 5 (August 15, 2012):
Denison Mines (USA) Corp. 2012. Responses to Interrogatories – Round 1 for
Reclamation Plan, Revision 5.0, March 12. May 31.

BASIS FOR INTERROGATORY:
The slope stability analyses presented by the Licensee uses the same shear strength parameters (phi=26
degrees, c=900 psf) for the reclamation cover, impoundment dikes, and the foundation soils above the
bedrock. These properties were derived from limited triaxial testing of very stiff / very dense material
recovered from apparently in-situ soil. Given that the different soil zones in the cover system are to be
placed with varying degrees of compaction (some being quite loose) and that the density of the dikes may
vary from that of the foundation, the use of singular soil properties throughout the analyses is
inappropriate. Shear strength parameters and other soil properties such as unit weight should be
assigned to the various earthen components consistent with soil type, degree of compaction, and
anticipated degree of variability. The selection of strength parameters should also be explained and
justified. Because of the relatively loose state proposed for some of the cover soils, the Licensee’s stated
approach (i.e., “circular failure surface analyses were conducted by targeting deeper, full-slope failures
as opposed to shallower, superficial failures.”) may miss truly critical failure surfaces. Shallow surfaces
as well as non-circular ones should be considered.
The slope stability analyses performed by the Licensee assume that the tailings impoundment cells behave
fully drained, thus phreatic surfaces were not included in the analyses. The Licensee should demonstrate
that such assumptions are appropriate (i.e., are at least consistent with, if not conservatively interpreted)
based on the results of drainage/seepage analyses representing conditions immediately at closure as well
as at the end of the design storage life of the facility. Such analyses should reflect the variations in the
tailings properties and drainage systems (slimes dewatering systems) particular to each tailings
management cell (e.g., approximately 600-ft by 400-ft area containing slimes “burrito drain” array in
each of Cell 2 and Cell 3 vs. area blanket sand layer and slimes drain piping system in Cells 4A and 4B;
). Tailings properties will vary in response to variations in historic (and future) milling processes as well
as deposition history (and future) and discharge –related distribution within each cell. The soil shear
strength parameters (particularly those of the tailings) used in the slope stability analyses should be
consistent with the drainage conditions thus demonstrated.
As described in the Basis for Interrogatory section of “INTERROGATORY WHITEMESA RECPLAN
REV. 5.0 R313-24-4; 10CFR40 APPENDIX A, CRITERION 4; INT 07/1: TECHNICAL ANALYSIS -
SETTLEMENT AND POTENTIAL FOR COVER SLOPE REVERSAL AND/OR COVER LAYER
August 15, 2012
Interrogatory 06/1: R313-24-4; 10CFR40.Appendix A, Criterion 1: Slope Stability Page 31 of 117
CRACKING”, the tailings dewatering analyses presented in Appendix H to the Updated Tailings Cover
Design Report, do not adequately represent (i.e., account for) potential variations in the tailings
properties, nor their potential distribution within the various tailings management cells. As requested in
the interrogatory cross-referenced above, the tailings dewatering analyses should be revisited or at least
clarified and better substantiated, and the Licensee should test actual tailings specimens from the site.
The number of specimens involved should be commensurate with anticipated variability of the tailings
conditions in the containment cells.
The slope stability analyses presented by the Licensee are based on a selected cross-section in Cell 4A
apparently intended to represent the greatest height of an otherwise uniformly designed embankment.
However, different conditions exist in Cell 1 adjacent to Cell 2 where mill debris and contaminated soils
are to be placed and covered. The slope stability of this section should be analyzed.
To aid future review, the shading applied to the slices of the failure mass should be removed (thus
enabling the profile lines of the underlying soil type to be seen). It is also suggested that contours for the
factor of safety be added to the search grid as well as definitions of the search radii.
The explanation and justification for the factor applied to the PGA to establish the pseudo-static
coefficient provided by the Licensee appears to be flawed. The Licensee’s report reads thusly:
“The seismic coefficient represents an inertial force due to strong ground motions during the
design earthquake, and is represented as a fraction of the PGA at the site (typically at the base of
the structure). Tetra Tech (2010) recommended using a value of 0.1 g for the seismic coefficient
in accordance with IBC (2006) recommendations to multiply the PGA by 0.667 to determine a
design acceleration value. The strategy of representing the seismic coefficient as a fraction of the
PGA has been adopted in review of uranium tailings facility design and documented in DOE
(1989). A value of 0.667 typically represents post-reclamation conditions. Based on this
guidance and the recommendations in Tetra Tech (2010), the seismic coefficient used for the
pseudo-static stability analysis was 0.1 g.”
The 2006 International Building Code (IBC) does not contain such a recommendation (it does not discuss
pseudo-static slope analysis). The code does use a factor of 2/3 to convert MCE ground accelerations to
design accelerations for structural components, but this is an issue separate from and not related to the
seismic coefficient used for slope stability. Explain why reference is made to the IBC since that document
is for the design of buildings and not earthen tailings impoundments, or revise the discussion accordingly
to more clearly state the justification for use of the selected seismic coefficient.
Assessment of slope stability under seismic conditions is dependent upon the Licensee’s seismic hazard
analysis. Any revisions to the seismic hazard analysis may necessitate revisions to this assessment.
NUREG-1620 (NRC 2003), Section 2.2.3 specifies that: “The analysis of slope stability will be acceptable
if it meets the following criteria:
(1) Slope characteristics are properly evaluated.
(a) Cross sections and profiles of natural and cut slopes whose instability would directly or indirectly
affect the control of radioactive materials are presented in sufficient number and detail to enable the
reviewer to select the cross sections for detailed stability evaluation.
(b) Slope steepness is a minimum of five horizontal units (5h) to one vertical unit (1v) or less. The use of
slopes steeper than 5h:1v is considered an alternative to the requirements in 10 CFR Part 40, Appendix
A, Criterion 4(c). When slopes steeper than 5h:1v are proposed, a technical justification should be
offered as to why a 5h:1v or flatter slope would be impractical and compensating factors and conditions
are incorporated in the slope design for assuring long-term stability.
August 15, 2012
Interrogatory 06/1: R313-24-4; 10CFR40.Appendix A, Criterion 1: Slope Stability Page 32 of 117
(c) Locations selected for slope stability analysis are determined considering the location of maximum
slope angle, slope height, weak foundation, piezometric level(s), the extent of rock mass fracturing (for an
excavated slope in rock), and the potential for local erosion.
(2) An appropriate design static analysis is presented.
(a) The analysis includes calculations with appropriate assumptions and methods of analysis (NRC, 1977).
The effect of the assumptions and limitations of the methods used is discussed and accounted for in the
analysis. Acceptable methods for slope stability analysis include various limit equilibrium analysis or
numerical modeling methods.
(b) The uncertainties and variability in the shape of the slope, the boundaries and parameters of the several
types of soils and rocks within and beneath the slope, the material properties of soil and rock within and
beneath the slope, the forces acting on the slope, and the pore pressures acting within and beneath the slope
are considered.
(c) Appropriate failure modes during and after construction and the failure surface corresponding to the
lowest factor of safety are determined. The analysis takes into account the failure surfaces within the slopes,
including through the foundation, if any.
(d) Adverse conditions such as high water levels from severe rain and the probable maximum flood are
evaluated.
(e) The effects of toe erosion, incision at the base of the slope, and other deleterious effects of surface runoff
are assessed.
(f) The resulting safety factors for slopes analyzed are comparable to the minimum acceptable values of
safety factors for slope stability analysis given in NRC Regulatory Guide 3.11 . . . .
(3) Appropriate analyses considering the effect of seismic ground motions on slope stability are presented.
(a) Evaluation of overall seismic stability, using pseudostatic analysis or dynamic analysis, as appropriate
(U.S. Army Corps of Engineers, 1977; NRC, 1977). Alternatively, a dynamic analysis following Newmark
(1965) can be carried out to establish that the permanent deformation of the disposal cell from the design
seismic event will not be detrimental to the disposal cell. The reviewer should verify that the yield
acceleration or pseudostatic horizontal yield coefficient necessary to reduce the factor of safety against
slippage of a potential sliding mass to 1.0 in a “Newmark-type” analysis has been adequately estimated
(Seed and Bonaparte, 1992).
b) An appropriate analytical method has been used. A number of different methods of analysis are available
(e.g., slip circle method, method of slices, and wedge analysis) with several variants of each (Lambe and
Whitman, 1979; U.S. Army Corps of Engineers, 1970b; NRC, 1977; Bromhead, 1992). Limit-equilibrium
analysis methods do not provide information regarding the variation of strain within the slope and along the
slip surface. Consequently, there is no assurance that the peak strength values used in the analysis can be
mobilized simultaneously along the entire slip surface unless the material shows ductile behavior (Duncan,
1992). Residual strength values should be evaluated if mobilized shear strength at some points is less than the
peak strength. The reviewer should ensure that appropriate conservatism has been incorporated in the
analysis using the limit equilibrium methods. The limit equilibrium analysis methodologies may be replaced
by other techniques, such as finite element or finite difference methods. If any important interaction effects
cannot be included in an analysis, the reviewer must determine that such effects have been treated in an
August 15, 2012
Interrogatory 06/1: R313-24-4; 10CFR40.Appendix A, Criterion 1: Slope Stability Page 33 of 117
approximate but conservative fashion. The engineering judgment of the reviewer should be used in assessing
the adequacy of the resulting safety factors (NRC, 1983a,b).
(c) For dynamic loads, the dynamic analysis includes calculations with appropriate assumptions and
methods (NRC, 1977; Seed, 1967; Lowe, 1967; Department of the Navy, 1982a,b,c; U.S. Army Corps of
Engineers, 1970a,b, 1971, 1972; Bureau of Reclamation, 1968). The effect of the assumptions and limitations
of the methods used is discussed and accounted for in the analysis.
(d) For dynamic loads, a pseudostatic analysis is acceptable in lieu of dynamic analysis if the strength
parameters used in the analysis are conservative, the materials are not subject to significant loss of strength
and development of high pore pressures under dynamic loads, the design seismic coefficient is 0.20 or less,
and the resulting minimum factor of safety suggests an adequate margin, as provided in NRC Regulatory
Guide 3.11 (NRC, 1977).
(e) For pseudostatic analysis of slopes subjected to earthquake loads, an assumption is made that the
earthquake imparts additional horizontal force acting in the direction of the potential failure (U.S. Army
Corps of Engineers, 1970b, 1977; Goodman, 1989). The critical failure surface obtained in the static
analysis is used in this analysis with the added driving force. Minimum acceptable values for safety factors of
slope stability analysis are given in Regulatory Guide 3.11 (NRC, 1977).
(f) The assessment of the dynamic stability considers an appropriate design level seismic event and/or strong
ground motion acceleration, consistent with that identified in Chapter 1 of this review plan. Influence of local
site conditions on the ground motions associated with the design level event is evaluated. The design seismic
coefficient to be used in the pseudostatic analysis is either 67 percent of the peak ground acceleration at the
foundation level of the tailings piles for the site or 0.1g, whichever is greater.
(g) If the design seismic coefficient is greater than 0.20g, then the dynamic stability investigation (Newmark,
1965) should be augmented by other appropriate methods (i.e., finite element method), depending on specific
site conditions.
h) In assessing the effects of seismic loads on slope stability, the effect of dynamic stresses of the design
earthquake on soil strength parameters is accounted for. As in a static analysis, the parameters such as
geometry, soil strength, and hydrodynamic and pore pressure forces are varied in the analysis to show that
there is an adequate margin of safety.
(i) Seismically induced displacement is calculated and documented. There is no universally accepted
magnitude of seismically induced displacement for determining acceptable performance of the disposal cell
(Seed and Bonaparte, 1992; Goodman and Seed, 1966). Surveys of five major geotechnical consulting firms
by Seed and Bonaparte (1992) indicate that the acceptable displacement is from 15 to 30 cm [6 to 12 in.] for
tailings piles. The reviewer should ensure that this criterion is also augmented by provisions for periodic
maintenance of the slope(s).

REFERENCES
International Building Code 2006. International Code Council, Inc.
MWH Americas 2011. Appendix E – Slope Stability Analysis, contained in Appendix D, Updated
Tailings Cover Design Report, White Mesa Mill, September 2011 to the Reclamation Plan, White Mesa
Mill, Rev. 5.0, September 2011.
August 15, 2012
Interrogatory 06/1: R313-24-4; 10CFR40.Appendix A, Criterion 1: Slope Stability Page 34 of 117
Tetra Tech, Inc. (Tetra Tech) 2010. “White Mesa Uranium Facility Seismic Study Update for a Proposed
Cell,” Technical Memorandum to Denison Mines, February 3.
U.S. Department of Energy (DOE) 1989. Technical Approach Document, Revision II, UMTRADOE/AL
050425.0002, Uranium Mill Tailings Remedial Action Project, Albuquerque, New Mexico.
NRC 1982. U.S. Nuclear Regulatory Commission, “Regulatory Guide 3.8; Preparation of Environmental
Reports for Uranium Mills”, Washington DC, Rev. 2, October 1982.
NRC 2003. Standard Review Plan (NUREG–1620) for Staff Reviews of Reclamation Plans for Mill
Tailings Sites Under Title II of The Uranium Mill Tailings Radiation Control Act”, NUREG-1620, June
2003.
NRC 2008. DG-3024, “Standard Format and Content of License Applications for Conventional
Uranium Mills,” Draft Regulatory Guide DG-3024, May, 2008.
August 15, 2012
Interrogatory 07/1: R313-24-4; 10CFR40.Appendix A, Criterion 4: Technical Analysis – Settlement and Potential for Cover Slope Reversal and/or
Cover Layer Cracking Page 35 of 117
INTERROGATORY WHITEMESA RECPLAN REV. 5.0; R313-24-4; 10 CFR 40 APPENDIX A,
CRITERION 4; INT 07/1: TECHNICAL ANALYSIS - SETTLEMENT AND POTENTIAL FOR
COVER SLOPE REVERSAL AND/OR COVER LAYER CRACKING

REGULATORY BASIS
Refer to UAC R313-24-4 which invokes the following requirement from 10CFR40, Appendix A, Criterion
4: “The following site and design criteria must be adhered to whether tailings or wastes are disposed of
above or below grade:
…(c) Embankment and cover slopes must be relatively flat after final stabilization to minimize erosion
potential and to provide conservative factors of safety assuring long-term stability. The broad objective
should be to contour final slopes to grades which are as close as possible to those which would be
provided if tailings were disposed of below grade; this could, for example, lead to slopes of about 10
horizontal to 1 vertical (10h:1v) or less steep. In general, slopes should not be steeper than about 5h:1v.
Where steeper slopes are proposed, reasons why a slope less steep than 5h:1v would be impracticable
should be provided, and compensating factors and conditions which make such slopes acceptable should
be identified.
(d) A full self-sustaining vegetative cover must be established or rock cover employed to reduce wind and
water erosion to negligible levels.
Where a full vegetative cover is not likely to be self-sustaining due to climatic or other conditions, such as
in semi-arid and arid regions, rock cover must be employed on slopes of the impoundment system. The
Executive Secretary will consider relaxing this requirement for extremely gentle slopes such as those
which may exist on the top of the pile.
…Rock covering of slopes may be unnecessary where top covers are very thick (or less); bulk cover
materials have inherently favorable erosion resistance characteristics; and, there is negligible drainage
catchment area upstream of the pile and good wind protection as described in points (a) and (b) of this
criterion.
Furthermore, all impoundment surfaces must be contoured to avoid areas of concentrated surface runoff
or abrupt or sharp changes in slope gradient.

INTERROGATORY STATEMENT
Refer to Appendix D, Updated Tailings Cover Design Report of the Reclamation Plan, Rev. 5, and
Drawings TRC-1 through TRC-8 in the Reclamation Plan, Rev. 5.0 :
1. Please revise (i.e., steepen) the slopes of the top slope portions of the final cover system to
provide an adequate factor of safety to ensure long-term stability of the covered embankment
area considering:

a. The potential for future slope reversal(s) and/or cracking to occur in the cover system
due to long-term total and differential settlement or subsidence which could lead to
conditions where ponding of precipitation could occur on the cover system in the future,
after the end of the active institutional control period; and

b. The significant disparity between the presently proposed topslope inclination ranges and
published recommended ranges of slopes for final cover systems for uranium mill tailings
repositories, surface impoundments, and landfills – namely ranging between 2% to 5%
(e.g., see DOE 1989; EPA 1989; EPA 1991, and ITRC 2003 and EPA 2004).
August 15, 2012
Interrogatory 07/1: R313-24-4; 10CFR40.Appendix A, Criterion 4: Technical Analysis – Settlement and Potential for Cover Slope Reversal and/or
Cover Layer Cracking Page 36 of 117
OR, alternatively, provide additional evaluations that clearly and unequivocally demonstrate (1)
the ability to construct such gently sloped cover systems as proposed, designed, and specified and
(2) the ability of the proposed embankment closure cover design to accommodate settlement-
induced slope changes (including slope reversal) without increasing infiltration into the
stabilized tailings impoundment.
Response 1 (August 31, 2012):
This response supersedes the response provided in the May 31, 2012 submittal.
In the Basis for Interrogatory, it is stated that the top cover slopes range from 0.1 to 1 %.
This is not correct. The top cover slopes range from 0.5 to 1%.
While the EPA references listed above specify cover slopes of 2 to 5 %, they are for
landfill covers, which cover materials with significantly different settlement characteristics
and have different erosional stability performance criteria than uranium mill tailings
impoundments.
Denison does not currently plan to steepen the top cover slopes. As noted in Response
2 to Interrogatory 03/1, cover with similar slopes have been permitted and constructed
for Uranium Mill Tailings Radiation Control Act (UMTRCA) Title I and II sites including:
• Falls City Title I site in Texas (less than 1% cover slopes)
• Bluewater Title II site in New Mexico (0.5 – 4% cover slopes)
• Conquista Title II site in Texas (0.5 – 1% cover slopes)
• Highland Title II site in Wyoming (0.5 – 2% cover slopes)
• Panna Maria Title II site in Texas (0.5% cover slopes)
• Ray Point Title II site in Texas (0.5 – 1% cover slopes)
• Sherwood Title II site in Washington (0.25% cover slopes)
• L-Bar Title II site in New Mexico (0.1% cover slopes)
Denison has conducted cover cracking analyses for the highly compacted cover layer
and evaluated differential settlements. The results are discussed in Response 2.
2. Provide technical justification for 1) quantitative acceptance criteria to be used as the basis for
evaluating the potential for slope reversal within the cover system in terms of potential long-term
total and differential settlement, 2) quantitative assessments of maximum tensile strain capacity
and other engineering properties such as Atterberg limits of the materials to be used in design of
the cover system, and 3) quantitative acceptance criteria, including maximum allowable linear
and angular distortion values, including effects of bending within any select layer or layers of the
cover, and (4) the minimum acceptable factor of safety for concluding that cover layer cracking
will not occur.
Response 2 (August 15, 2012):
This response supersedes the response provided in the May 31, 2012 submittal.
Denison has conducted revised settlement analyses to update the analyses presented in
the Reclamation Plan, Revision 5.0 (Denison, 2011). These analyses were used to
evaluate differential settlement of the cover system and the potential for cover cracking.
Additional discussion on the revised settlement analyses and evaluation of differential
settlement and cover cracking is provided below.
The results of the analyses indicate that cover cracking of the highly compacted radon
barrier is unlikely. Evaluation of the differential settlement in Cell 2 indicates that the
majority of the total settlement due to final cover placement and creep will occur within
August 15, 2012
Interrogatory 07/1: R313-24-4; 10CFR40.Appendix A, Criterion 4: Technical Analysis – Settlement and Potential for Cover Slope Reversal and/or
Cover Layer Cracking Page 37 of 117
the first five years after placement of the final cover. During this time period, additional
fill can be placed in any low areas in order to maintain positive drainage of the cover
surface. The total estimated settlement that could occur (due to primary consolidation
associated with final cover loading, secondary creep, and seismic settlement) once five
years has elapsed since final cover placement is estimated to range from 0.52 to 0.83
feet. This indicates that the maximum potential differential settlement that could be
expected between adjacent movement monitoring locations would be on the order of 0.3
feet. This estimated differential settlement is sufficiently low that ponding is not
expected to occur on a cover slope of 0.5 percent. In addition, it is not expected that the
differential settlement is significant enough for slope reversal to occur.

Settlement Analyses
Twenty settlement monuments were installed in Cell 2 and six monuments were installed
in the east portion of Cell 3. Monuments were installed shortly after interim cover was
placed over the tailings (Roberts, 2012). The locations of the existing settlement
monument locations were presented in Figure I.2 of Appendix D to Reclamation Plan,
Revision 5.0 (Denison, 2011). This figure has been provided in Attachment E for ease of
reference.
The revised settlement analyses focused on evaluating measured settlement monument
data for Cell 2, which has the longest period of record for measured settlement data and
includes monitoring data during dewatering which began in 2009. Cell 3 was not
included in the revised analyses due to limited measured settlement monitoring data. In
addition, interim cover is placed over only a portion of Cell 3 and dewatering has not yet
been started.
One-dimensional analyses of primary consolidation were conducted at select locations
(specifically at each settlement monitoring point) for Cell 2 to evaluate settlement during
1) interim cover loading, 2) tailings dewatering, 3) final cover loading. In addition
estimates were made of settlement due to creep associated with secondary
consolidation during each these phases. Estimates were also made of seismically-
induced settlement due to earthquake loadings. The revised settlement analyses are an
update to the analyses presented in Reclamation Plan Revision 5.0 (Denison, 2011).
Revisions from the analyses presented in Denison (2011) include incorporation of
additional settlement data, revisions to measured monitoring data used in the analyses
based on information provided by Denison (Roberts, 2012 and Turk, 2012) and further
evaluation of the data, selection of representative settlement monitoring locations based
on data quality for use in the analyses, and incorporation of evaluation of settlement due
to creep and seismic conditions. The revised settlement analyses are provided in
Attachment E.
The analyses of primary consolidation settlement are separated into three phases, as
presented in Attachment E. The phases are listed below:
• Phase 1 – Primary consolidation settlement due to interim
cover loading. The time period for this phase is estimated to have begun with
the placement of interim cover and effectively ended prior to the start of
dewatering. Settlement measurements made during this phase were used to
estimate consolidation parameters for the analyses of subsequent phases.

August 15, 2012
Interrogatory 07/1: R313-24-4; 10CFR40.Appendix A, Criterion 4: Technical Analysis – Settlement and Potential for Cover Slope Reversal and/or
Cover Layer Cracking Page 38 of 117
• Phase 2 – Primary consolidation settlement due to dewatering.
The time period for this phase is estimated to extend from the start of dewatering
until the placement of final cover.

• Phase 3 – Primary consolidation settlement due to final cover
loading. The time period for this phase is estimated to be from the time of final
cover placement until primary consolidation due to final cover loading is
complete.
Creep settlement and seismic settlement were calculated and presented separately from
primary consolidation settlement in Attachment E.
Depth of tailings at each monument location was estimated as presented in Denison
(2011) by comparing the base of the cells with the estimated top surface of tailings. The
top surface of tailings is assumed to be 18 inches below the top of berm, or at the top of
the flexible membrane liner (FML). The depth of existing interim cover was estimated to
be the difference between the top of tailings and the ground surface as estimated from a
LiDar survey taken in 2007. The final cover thickness was estimated as the maximum
cover thickness determined from the radon modeling (see Attachment H). The
references for the material properties of the tailings and cover soils used in the analyses
are listed in Attachment E
Estimation of Consolidation Parameters
The Compression index (Cc) of the tailings (used for calculation of the amount of primary
consolidation within saturated portions of the tailings) was estimated for eighteen of the
twenty settlement monitoring locations in Cell 2 for the time period before the start of
dewatering. One of the locations (2W5-N) did not have adequate data and was
excluded from the estimation. The second location excluded from the analyses (2W5-S)
was not monitored until after dewatering had begun. The Cc was calculated based upon
classical one-dimensional consolidation theory (Terzaghi et al, 1996) using the
measured settlement for the Phase 1 time period and the estimated initial tailings void
ratio presented in the settlement analyses in Denison (2011). The thickness of saturated
tailings used for Phase I consolidation was estimated using the water elevation within
the tailings at the start of dewatering, based on discussions with Denison (Roberts,
2012). A capillary fringe of nearly-saturated tailings above the water elevation was
conservatively assumed to also undergo primary consolidation. This capillary fringe was
assumed to extend approximately 8 feet above the water level in the tailings based upon
information provided in Fredlund et al. (2003), using the measured percent passing the
number 200 sieve and the plasticity index of the tailings, and assuming 90% saturation
or higher within the capillary fringe that is subject to primary consolidation. An additional
3 feet was added to the saturated thickness estimated for the tailings to account for
perched saturated zones in the tailings above the capillary fringe. The results of the
analyses are presented in Table 1. The average value estimated for Cc is 0.39 and is
within the range of typical published values of sands to slime tailings of 0.06 to 0.566
(Keshian and Rager, 1988). The laboratory gradations for the tailings indicate an
average fines content of 30 to 43 percent, which corresponds to the Keshian and Rager
(1988) definition of sand/slimes (fines content between 30 and 70 percent).
Five monitoring locations from Cell 2 where primary consolidation settlement was
observed were used to estimate the coefficient of consolidation, cv, using traditional
consolidation theory (Terzaghi et al, 1996) and the square-root-of-time fitting method.
Figures for the five settlement locations used in the analyses are provided in Attachment
August 15, 2012
Interrogatory 07/1: R313-24-4; 10CFR40.Appendix A, Criterion 4: Technical Analysis – Settlement and Potential for Cover Slope Reversal and/or
Cover Layer Cracking Page 39 of 117
E. The results of the analyses are presented in Attachment E and summarized below in
Table 1. For the thirteen monitoring locations not included in the analyses, measured
settlements due to placement of the interim cover were too small to develop curves for
accurate estimation of cv values. The small settlement values indicate that primary
consolidation occurred during placement of the interim cover and it can be reasonably
be assumed that a similar response (i.e. primary consolidation occurring during
construction) will be seen at these locations during final cover placement. The range of
calculated cv values is 0.00034 to 0.00539 cm2/s. The average value estimated for cv,
0.00176 cm2/s is within the range of typical published values of sands to slime tailings of
0.001 to 0.05 cm2/s (Keshian and Rager, 1988).

Table 1. Estimated Compression Index and Coefficient of Consolidation Values
Cc cv (cm2/s)
Minimum Value 0.02 0.00034
Maximum Value 1.30 0.00539
Average Value 0.39 0.00176

Results of Settlement Analyses
The estimated Cc values for eighteen of twenty monitoring locations on Cell 2 were used
to estimate the total settlement due to dewatering. The dewatering analyses presented
in MWH (2010) were used to estimate the final water level in the tailings after
dewatering. MWH (2010) estimated an average saturated thickness of approximately
3.5 feet at the end of dewatering. A final water level at the end of dewatering was
estimated based on this value using the stage-storage curve for Cell 2. The results of
the dewatering settlement estimates are provided in Attachment E. The total settlement
due to placement of interim cover and dewatering is summarized in Table 2 and ranges
from 0.01 to 1.96 feet. Based upon the results of settlement monitoring, it appears that
primary consolidation due to interim cover loading was effectively complete prior to
commencement of dewatering. The cv values estimated from the Phase 1 settlement
monitoring data were used to calculate the time to reach 90 percent of primary
consolidation due to dewatering of the tailings in Cell 2 for five monitoring locations. The
results are summarized in Table 2 and range from 0.14 to 0.63 years. The one-
dimensional analyses of Phase 2 consolidation assume the tailings are completely
underlain by a high-permeability drain layer, and that an instantaneous drop to the final
water elevation occurs in this layer at the start of dewatering. These assumptions will
result in consolidation due to dewatering occurring at a rate described by the classical
pore-pressure dissipation curve for double-drained conditions (Lambe and Whitman,
1969). It should be noted the assumptions made in the one-dimensional consolidation
analyses of Phase 2 (i.e. complete coverage of the tailings impoundment by an infinitely-
permeable underdrain system, and instantaneous drawdown to final water level) do not
exist within the impoundment, and will result in an underestimation of the time required
to achieve 90% consolidation. The results of the tailings dewatering analysis, which
includes the 3-dimensional aspects of flow toward the underdrain strips, and a finite
underdrain permeability, are considered to provide a more reliable estimate of the
duration Phase 2 consolidation.
August 15, 2012
Interrogatory 07/1: R313-24-4; 10CFR40.Appendix A, Criterion 4: Technical Analysis – Settlement and Potential for Cover Slope Reversal and/or
Cover Layer Cracking Page 40 of 117
The total settlement due to final cover placement was estimated for the eighteen
monitoring locations using the estimated Cc values and the final water level estimated
from MWH (2010). The results are provided in Attachment E and summarized in Table
2. The estimated cv values were used to estimate the time to reach 90 percent
consolidation due to placement of the final cover in Cell 2 for five monitoring locations.
The results are presented in Attachment E and summarized in Table 2. The values for
time to reach 90 percent consolidation due to final cover placement range from 0.42 to
2.12 years. Based upon the settlement monitoring results obtained after interim cover
placement, it is conservatively assumed 90% consolidation will be achieved during
placement of the final cover at the other monitoring locations, as discussed previously.
Creep settlement was estimated using the method presented in Holtz and Kovacs (1981)
using the average value of Cc and assuming a typical value for the Cα/Cc ratio for
saturated soils from Terzaghi et al. (1996). The time period used for analysis of creep
settlement was 1000 years. The results are presented in Attachment E and summarized
in Table 2. The range of values for creep settlement is 0.09 to 0.31 feet. Approximately
one third of the creep settlement is estimated to occur within the first five years of
placement of the final cover.
Seismic settlement was estimated using methods presented in Stewart and Wang
(2003) and seismic parameters presented in the updated seismic study provided in the
May 31, 2012 response document. An uncorrected (SPT) blow count of 2 in 12 inches
was conservatively assumed for the tailings. The results are presented in Attachment E
and summarized in Table 2. The range of values for seismic settlement is 0.46 to 0.60
feet.

Table 2 Summary of Settlement Results
Parameter Min. Max. Ave.
Total Settlement due to Interim Cover Placement and
Dewatering (ft) 0.02 1.49 0.31
Total Settlement due to Final Cover Placement (ft) 0.02 1.34 0.34
Total Settlement due to Seismic Event (ft) 0.46 0.60 0.53
Total Settlement due to 1000 Years of Creep (ft) 0.09 0.31 0.22
Total Settlement five years after placement of Final
Cover due to Final Cover Placement, Creep, and a
Seismic Event (ft) 0.52 0.83 0.68
Time to Reach 90% Primary Consolidation due to
Dewatering (yrs) 0.14 0.63 0.34
Time to Reach 90% Primary Consolidation Following
Final Cover Placement (yrs) 0.42 2.12 1.03

Differential Settlement and Cover Cracking Analysis
The majority of the total settlement due to final cover placement and creep will occur
within the first five years after placement of the final cover. During this time period,
additional fill can be placed in any low areas in order to maintain positive drainage of the
cover surface. The total estimated settlement that could occur (due to primary
August 15, 2012
Interrogatory 07/1: R313-24-4; 10CFR40.Appendix A, Criterion 4: Technical Analysis – Settlement and Potential for Cover Slope Reversal and/or
Cover Layer Cracking Page 41 of 117
consolidation associated with final cover loading, secondary creep, and seismic
settlement) once five years has elapsed since final cover placement is estimated to
range from 0.52 to 0.83 feet. This indicates that the maximum potential differential
settlement that could be expected between adjacent movement monitoring locations
would be on the order of 0.3 feet. This estimated differential settlement is sufficiently low
that ponding is not expected to occur on a cover slope of 0.5 percent. In addition, it is
not expected that the differential settlement is significant enough for slope reversal to
occur.
Cover cracking analyses were evaluated for the highly compacted radon barrier for the
timer period after placement of the final cover. The maximum differential total settlement
due to final cover placement, creep, and a seismic event is 1.66 feet between the
settlement monument 2W3-S and the edge of the tailings cell (conservatively estimated
to have settlement equal to 0). The horizontal distance between the two locations is
approximately 230 feet. However, the differential settlement between monitoring point
2W4-S and the edge of the tailings cell of 0.9 feet in 100 feet was used for the cover
cracking analyses because the resulting horizontal strain is larger for this case.
Morrison-Knudsen Environmental Corporation (1993) presents a method for determining
the tensile strain required to cause cracking of the radon barrier as a function of the
plasticity index (PI) of the soil. The tensile strain at cracking is calculated by the
equation below:
εf (%) = 0.05 +0.003 x (PI)
where: εf(%) = tensile strain to cause cracking of the radon barrier, and
PI = plasticity index of radon barrier.
The PI value for the highly compacted radon attenuation layer was conservatively
estimated as the lowest measured PI (0) for composite samples collected during the
April 2012 borrow investigation (see Attachment B.2). Using this value for PI, the
tensile strain to cause cracking is 0.05 percent. The maximum horizontal tensile strain
on the radon attenuation layer must be less than 0.05 percent so that cover cracking will
not occur.
The horizontal movement at the top of the radon barrier can be calculated based on the
following equation (Lee and Shen, 1969), which is referenced in NUREG 1620 (NRC,
2003) for cover cracking analysis:
αHm3
2=
where: m = horizontal movement in feet,
H = thickness of relatively incompressible material (radon barrier overlying the
random fill), and
α = local slope of the settlement profile (expressed as decimal fraction).
The horizontal movement at the maximum tailing thickness is calculated to be 0.028 feet
using a maximum thickness of relatively incompressible material of 4.7 feet, and a total
differential settlement of 0.9 feet over 100 feet. The thickness of relatively
incompressible material was estimated assuming a maximum 4.7-ft highly compacted
radon barrier.
August 15, 2012
Interrogatory 07/1: R313-24-4; 10CFR40.Appendix A, Criterion 4: Technical Analysis – Settlement and Potential for Cover Slope Reversal and/or
Cover Layer Cracking Page 42 of 117
The horizontal strain between any two settlement monitoring locations is the maximum
horizontal movement divided by the horizontal distance (0.028 ft/100 ft). Using these
values, the maximum horizontal strain is calculated as 0.028 percent. This value is
lower than the maximum allowable strain of 0.05 percent. This indicates that cracking of
the radon attenuation layer is not likely.

References for Response 2 (August 15, 2012):
Denison Mines (USA) Corporation (Denison), 2011. Reclamation Plan, Revision 5.0,
White Mesa Mill, Blanding, Utah, September.
Fredlund, M.D., Fredlund, D.G., Houston, S.L., and Houston, W., 2003. Assessment of
Unsaturated Soil Properties for Seepage Modeling Through Tailings and Mine
Wastes, Proceedings of Tailings and Mine Waste 2003.
Holtz, R.D. and Kovacs, W.D., 1981. An Introduction to Geotechnical Engineering.
Prentice Hall, Inc. New Jersey.
Keshian, B., and Rager, R. 1988. Geotechnical Properties of Hydraulically Placed
Uranium Mill Tailings, in Hydraulically Fill Structures, Geotechnical Special
Publication No. 21, Eds. Van Zyl, D., and Vick, S., ASCE, August.
Lambe, T.W. and Whitman, R.V., 1969. Soil Mechanics. New York: John Wiley & Sons,
1969.
Lee, K.L., and C.K. Shen, 1969. “Horizontal Movements Related to Subsidence.”
Journal of Soil Mechanics and Foundation Division, ASCE Volume 95. January.
Morrison-Knudsen Environmental Corporation (Morrison-Knudsen), 1993. UMTRA-
Naturita, Embankment Design, Settlement Analysis and Cracking Potential
Evaluation. Calc. No. 17-740-02-01. May.
MWH Americas, Inc. (MWH), 2010. Denison Mines (USA) Corp. Revised Infiltration and
Contaminant Transport Modeling Report, White Mesa Mill Site, Blanding, Utah.
Report prepared for Denison Mines. March.
Roberts, H., 2012. Personal communication from Harold Roberts, Denison Mines (USA)
Corp., to Melanie Davis, MWH Americas, Inc. regarding water levels in Cell 2
prior to dewatering, as well as additional information on placement of settlement
monuments, July 26.
Stewart, L. P., and D. H. Whang, 2003. Simplified Procedure to Estimate Ground
Settlement from Seismic Compression in Compacted Soils. 2003 Pacific
Conference on Earthquake Engineering.
Terzaghi, K., R. Peck, and G. Mesri, 1996. Soil Mechanics in Engineering Practice, Third
Edition. John Wiley and Sons, Inc. New York.
Turk, D., 2012. Personal communication from David Turk, Denison Mines (USA) Corp.,
to Steve McManus, MWH Americas, Inc. regarding settlement monitoring
procedures and changes in measurement procedures and/or personnel during
measurement time period and on select measurement dates., August 1.
August 15, 2012
Interrogatory 07/1: R313-24-4; 10CFR40.Appendix A, Criterion 4: Technical Analysis – Settlement and Potential for Cover Slope Reversal and/or
Cover Layer Cracking Page 43 of 117
U.S. Nuclear Regulatory Commission (NRC), 2003. “Standard Review Plan for the
Review of a Reclamation Plan for Mill Tailings Sites Under Title II of Uranium Mill
Tailings Radiation Control Act of 1978, Final Report.” NUREG-1620. June.

3. Provide engineering analyses (including calculations and numerical modeling simulations as
applicable) documenting the range of anticipated total and differential settlements within each of
the containment cells. In doing so, use consolidation parameters obtained from site-specific
testing of the tailings materials, reflecting both spatial and temporal variations in the tailings.
Data from other sources may supplement (but not replace) site-specific test data in the analyses.
Response 3 (August 15, 2012):
This response supersedes the response provided in the May 31, 2012 submittal.
See Response 2. Denison will not be conducting site-specific testing of tailings.
Denison has updated estimations for consolidation parameters based on further
evaluation of historical settlement monitoring data and incorporation of more recent
settlement monitoring data. The analyses are consistent with tailings dewatering
analyses previously conducted. The consolidation analyses included sensitivity
analyses to evaluate a range of coefficients of consolidation and compression indices.

4. Demonstrate that tailings have been deposited in such a way that variations in tailings properties
by location do not compromise the stability of the tailings as a foundation for cover system
construction. Consider effects of sand-rich tailings zones lying adjacent to our near slime-rich
tailings zones, due to deposition during slurry flow. Describe and account for effects of any
different tailings placement methods (e.g., wet slurry vs. thickened slurry deposition) used
throughout the mill’s operating life. Identify and quantify the effects on stability of variations in
such tailings physical characteristics as moisture content, consolidation coefficients, specific
gravity, hydraulic conductivity (as listed in Appendix D Updated Tailings Cover Design Report,
September 2011). Perform and provide results of numerical analyses using this information to
project differential settlement across the tailings impoundments using software such as the Fast
Lagrangian Analysis of Continuum (FLAC®) code (Itasca 2009) or other similar software, as
appropriate. Alternatively, provide information to justify why such analyses are not warranted.
Response 4 (May 31, 2012 and August 15, 2012):
See Response 2. Knowledge of tailings discharge history with observation of the
response of tailings to interim cover placement (i.e. settlement monitoring) provide the
most reliable information for identifying the potential for, and location of slimes or other
soft zones. Interim cover has been placed over the tailings in Cell 2 and the portions of
Cell 3. No cover stability issues have been observed since placement of the interim
cover in either cell. Typically the worst-case foundation conditions for cover stability
occur as the interim cover is first placed and the saturated tailings thicknesses are at a
maximum. As the tailings dewater, settlement within the tailings is observed as the
effective stresses increase within the tailings. As tailings consolidation and settlement
occur, the stability of the tailings as a foundation for the cover system improves.
Observation and monitoring of the tailing behavior will continue be conducted as the
interim cover is being placed and dewatering progresses.

August 15, 2012
Interrogatory 07/1: R313-24-4; 10CFR40.Appendix A, Criterion 4: Technical Analysis – Settlement and Potential for Cover Slope Reversal and/or
Cover Layer Cracking Page 44 of 117
5. Include secondary settlement (i.e., creep) and any seismically induced settlement of the tailings in
settlement analyses and consider their effects when assessing the anticipated performance of the
cover system.
Response 5 (August 15, 2012):
This response supersedes the response provided in the May 31, 2012 submittal.
See Response 2. The revised settlement analyses include secondary (creep) settlement
and seismically induced settlement.

6. Demonstrate that the results of settlement analyses are consistent with results of
drainage/dewatering analyses. Ensure that drainage/dewatering analyses reflect the tailings and
drainage conditions (including slime drain system) existing in each cell.
Response 6 (August 15, 2012):
This response supersedes the response provided in the May 31, 2012 submittal.
See Response 2. As discussed in Response 2, the drainage/dewatering analyses more
accurately reflect underdrainage conditions than do the one-dimensional consolidation
analyses and as such, provide a more reliable estimate of the rates of primary
consolidation during the dewatering phase. The total amounts of consolidation
settlement are dependent on the initial and final water levels, and as such, the one-
dimensional consolidation analyses are seen as providing a realistic estimate of total
amount of primary consolidation settlement due to dewatering.

7. Perform and report results of sensitivity and uncertainty analyses to demonstrate that the cover
system will remain stable despite the effects of differential settlement. Report the time required to
reach 90% consolidation.
Response 7 (August 15, 2012):
This response supersedes the response provided in the May 31, 2012 submittal.
See Response 2.

8. As part of the analyses identified above, please also perform a seepage analyses to evaluate the
shape of the phreatic surface within the tailings prism for each representative area within Cells 2
and/or 3, 4A, and 4B to be analyzed for consolidation timeframes and in differential settlement
analyses. Ensure that effects of planned dewatering procedures and the dewatering system
design configuration in each specific cell analyzed are reflected in seepage analyses.
Response 8 (August 15, 2012):
This response supersedes the response provided in the May 31, 2012 submittal.
Sufficient information was provided in the dewatering analyses to estimate the rate at
which consolidation settlement will occur during dewatering. Supplemental seepage
analyses were not performed for the settlement analyses. The actual rates and amounts
of settlement occurring during the dewatering phase will continue to be monitored as
dewatering progresses to provide verification of the estimated settlements at each
monitoring location.
August 15, 2012
Interrogatory 07/1: R313-24-4; 10CFR40.Appendix A, Criterion 4: Technical Analysis – Settlement and Potential for Cover Slope Reversal and/or
Cover Layer Cracking Page 45 of 117

9. Provide sensitivity analyses to assess the effect a of changes in tailings coefficients of
consolidation parameters, void ratios, and tailings hydraulic conductivity values (note: it is
acknowledged that values of all of these parameters are subject to uncertainty) on the amount of
time required to reach approximately 90% consolidation of the tailings at each locations
assessed within each cell and/or across individual tailings cells.
Response 9 (August 15, 2012):
This response supersedes the response provided in the May 31, 2012 submittal.
Sensitivity analyses to variations in the rate parameters (as reflected in settlement
monitoring results) were performed for the 90 percent consolidation calculations and the
range of values are provided in Response 2 for Cell 2. The results for Cell 2 are
considered representative of the conditions that would be expected for Cell 3 and Cells
4A and 4B.

10. Using the information obtained from the analyses identified above, for each critical section
defined, complete differential settlement analyses and compare the analyses results to the
specified design criteria and evaluate the potential for slope reversal(s) to occur in the cover
system over the tailings cells over the worst-case sections analyzed.
Response 10 (May 31, 2012 and August 15, 2012):
See Response 2.

11. Provide information on the expected range of plasticity characteristics of the soil materials
proposed for use for constructing the highly compacted upper portion of the radon attenuation
and radon attenuation and grading layer of the proposed cover system, and specify design
criteria (including maximum allowable values of both linear and angular distortion) to be used
for evaluating the potential for cracking of this layer to occur as a result of any differential
settlement that may occur.
Response 11 (May 31, 2012 and August 15, 2012):
See Response 2.

BASIS FOR INTERROGATORY
The proposed cover slope (minimum of 0.1% to a maximum of 1.0 %) is very flat and, based on the
information provided, has to be considered to likely be problematic from the standpoint of potential long-
term subsidence/differential settlement. 10CFR 40, Appendix A, Technical Criterion 4(c) specifies that
embankment and cover slopes must be relatively flat after final stabilization to minimize erosion and
provide conservative factors of safety assuring long-term stability (emphasis added). Technical guidance
developed for and typically utilized by the U.S. Department of Energy on the UMTRA Project for design
and construction of uranium mill tailings repositories included typical repository topslope inclinations of
2 to 3 percent (U.S. DOE 1989, Section 3, Figure 3-3). Further, minimum technology guidance for final
cover systems for surface impoundments recommended by the USEPA (EPA 1989; EPA 1991) consists of
the following:
August 15, 2012
Interrogatory 07/1: R313-24-4; 10CFR40.Appendix A, Criterion 4: Technical Analysis – Settlement and Potential for Cover Slope Reversal and/or
Cover Layer Cracking Page 46 of 117
“…a top layer…, the surface of which slopes uniformly at least 3 percent but not more than 5
percent, to facilitate runoff while minimizing erosion, …”
Additionally, an EPA document published in 2004 (EPA) further discusses this guideline in the following
context:
“…[In the Draft Technical Guidance for RCRA/CERCLA Final Covers, EPA states that] most
landfill cover system top decks are designed to have a minimum inclination of 2% to 5%, after
accounting for settlement, to promote runoff of surface water. …However, [EPA states that] in
some cases involving the closure or remediation of existing landfills, waste piles, or source areas,
flatter slopes may already exist and that the cost to increase the slope inclination by fill
placement or waste excavation may be significant. In these cases, slightly flatter inclinations can
be considered if the future settlement potential can be demonstrated to be small, if concerns about
localized subsidence can be adequately addressed, and if monitoring and maintenance provisions
exist to repair areas of grade reversal or subsidence…”
The proposed cover topslope inclinations (minimum of 0.1%) are much flatter than the above
recommended ranges. The cover design should include a topslope slope inclination that ensures that an
adequate factor of safety is provided to maintain long-term stability of the completed embankment(s),
considering the potential for future slope reversal(s) due to long-term differential settlement or
subsidence, given a reasonable estimate of the range of different tailings characteristics and tailings
consolidation conditions that may exist within the different tailings placement cells. The final topslope
inclinations must ensure that the topslope portion of the embankment will maintain a positive slope
across the entire embankment after settlement/subsidence, thus providing lateral runoff of precipitation
without ponding throughout the performance period of the covered and closed embankment.
Drawings TRC-3 through TRC-8 of the Reclamation Plan Rev. 5.0 depict several areas where slopes are
nearly flat and have low-lying areas already (e.g. over portions of Cell 2) where differential settlement, if
it were to occur, could further aggravate these areas from the standpoint of further flattening or creating
of larger areas of flat ground surface for future ponding of incident precipitation.
Available published information and/or testing should be used to estimate the maximum amount of
strain/maximum distortion value that can be tolerated within the compacted layer over the design life of
the embankment and not crack the radon barrier. Such a limit should be based on properties (e.g., range
of plasticity indices) of the soils proposed for constructing the compacted portion of the radon barrier
layer. Engineering analyses should be provided for various representative disposal configurations
involving disposed tailings to demonstrate that predicted settlement/subsidence magnitudes and locations
will not exceed specified acceptance criteria for strain or distortion value.
To quantify the amount of settlement in the tailings due to the placement of the interim and final soil
covers, the Licensee has attempted to quantify the coefficients of consolidation (cv) and compression
indices (Cc) for the tailings based on back-analysis of existing settlement monitoring data from Cells 2
and 3. While this approach is a conceptually sound approach for obtaining site-specific parameters,
successful implementation often proves to be problematic. For instance, high quality monitoring data is
needed. Unfortunately, the monitoring data exhibits an appreciable amount of “noise” and numerous
erratic shifts, making it uncertain as to which data points are the "real data" to which the modeled
settlement response should be matched. This approach also typically requires that the initial portion of
the load-settlement curve be well defined. Without this initial data, the total amount of settlement
ultimately expected to occur can be difficult to accurately quantify, particularly if the rate of
consolidation is rapid relative to the rate of loading (i.e., cover placement). Any settlement occurring
during construction of the cover and before monitoring begins is lost, leading to questions as to how
tightly the “bend” in the time rate of consolidation curve should be matched in the absence of a well-
defined starting point for the settlement model. It should also be noted that assessing the goodness of the
fit itself can also be problematic. For example, while the report states that the model values of Cc and cv
August 15, 2012
Interrogatory 07/1: R313-24-4; 10CFR40.Appendix A, Criterion 4: Technical Analysis – Settlement and Potential for Cover Slope Reversal and/or
Cover Layer Cracking Page 47 of 117
were varied “until the observed settlement curve correlated well with the calculated settlement”, it is the
reviewer’s opinion that the degree of correlation achieved was not always “well”, particularly for the
first and most meaningful part of the consolidation time history curve shown in Fig F-1, and for the entire
plots shown for cells 2W1, 2W3, 3-1C, 3-1S. It may be simply fortuitous that the back-calculated values
appear to be within the ranges suggested Keshian and Rager (cited by the Licensee), particularly
recognizing that the ranges cover one or more orders of magnitude. It should also be noted that no
assessment has been made as to whether or not the tailings’ behavior in Cells 2 and 3 are applicable to
the other cells.
It is noted that the calculated/estimated amounts of settlement presented in the report appear to be based
on assumed dry and saturated unit weights of 86.3 and 117.1 pcf, respectively. However, elsewhere in
the report, (Section C.2.4 of sub-Appendix C in Appendix D), the tailings are described as having a dry
unit weight of 74.3 pcf. Consistent characterization of the tailings throughout the report seems to be
needed, or at least this variation should be accounted for when reporting values of settlement. It is also
noted that all the back analyses involved the same initial void ratio for the tailings which is a very
unlikely scenario given that the other consolidation parameters (which are not entirely independent of
void ratio) were varied.
A key deficiency of the settlement assessment presented by the Licensee lies in the following conclusion:
“Additional settlement due to the construction of the final cover is estimated to be on the order of 5 to 6
inches. The estimated amount of additional settlement is sufficiently low such that ponding is not
expected with a cover slope of 0.5 percent.” The calculated settlements are magnitudes of settlement
without specified locations, whereas an assessment of ponding potential (i.e., localized grade reversal of
the cover) requires that the spatial variation of settlement be known or calculated. The reported
magnitudes of vertical settlement need to be translated into reliable estimates of differential settlement in
order to properly assess the adequacy of the cover slope. In doing this, the Licensee should evaluate the
various areas within individual tailings placement cells and/or or spanning more than one of the tailings
Cells 2, 3, and 4A/B where tailings slurry deposition modes may vary, leading to different tailings
conditions within and/or between cells (e.g., tailings areas comprised of sand/slime mixture located
laterally adjacent to tailings areas containing mostly slimes, including, for example, areas near side slope
portions of tailings placement cells where more sand-rich tailings may be laterally juxtaposed against
slime-rich tailings areas). The analysis should particularly account for varying thicknesses of
compressible tailings along the side slopes of the cells as well as the potential for differences in stress
conditions along such slopes. The locations and characteristics for the different tailings materials (such
as moisture content, horizontal and vertical coefficients of consolidation, specific gravity, void ratios, unit
weights, hydraulic conductivity, etc.) should be clearly shown for one or more analyzed critical cross-
sections.
While the above discussion focuses on the settlement of tailings, different conditions exist in Cell 1
adjacent to Cell 2 where mill debris and contaminated soils instead of tailings are to be placed and
covered. Total and differential settlement based on the particular conditions of this cell together with
their effects on both the liner and cover systems should be assessed.
To more reliably quantify total and differential settlements as well as settlement rates for the tailings
impoundments, the Licensee should test tailings specimens to determine their consolidation properties.
The number of specimens involved should be commensurate with anticipated variability of the tailings
conditions in the containment cells. The Licensee should then consider performing coupled stress and
seepage analyses of critical cross-section of Cells 2 and 3, and/or 4A/B. As a minimum, the settlement
analyses should be compared with the drainage/seepage/dewatering analyses to demonstrate that they
are consistent. It appears that such a check was not performed since the discussion of the results of the
time-rate of consolidation/settlement does not make any reference to the dewatering analyses in sub-
Appendix H, despite the fact that the back-calculated coefficients of consolidation of the former should be
August 15, 2012
Interrogatory 07/1: R313-24-4; 10CFR40.Appendix A, Criterion 4: Technical Analysis – Settlement and Potential for Cover Slope Reversal and/or
Cover Layer Cracking Page 48 of 117
proportional to the hydraulic conductivity values of the latter (the coefficient of consolidation is a
composite variable which includes hydraulic conductivity).
Unfortunately, the tailings dewatering analyses presented in sub-Appendix H do not adequately represent
(i.e., account for) potential variations in the tailings properties, nor their potential distribution within the
containment cells. In the models presented for Cells 2 and 3, isotropic conditions are assumed (which is
very unlikely) and a single hydraulic conductivity value is assigned to all of the tailings (which might be
acceptable if the effect/sensitivity of the parameter had been assessed parametrically – but it wasn’t).
The hydraulic conductivity value itself appears to be flawed, apparently being based on the geometric
mean of four discrete hydraulic conductivity values taken from technical literature (representing four
generic soil types ranging from medium sand to silty clayey) which span 5 orders of magnitude. It is
inappropriate to use a type of average, single value to represent such a vast range of hydraulic
conductivity. (Although there is seemingly contradictory information as to what was really used as the
basis for the hydraulic conductivity in the analysis. On page J[sic]-4 of sub-Appendix H, the text states
that hydraulic conductivity values are based on testing from the Canon City Mill tailings whereas
attachment H-2 indicates that the hydraulic value is based on the aforementioned averaging of typical
values. Clarification is needed). The tailings dewatering analyses should be revisited or at least clarified
and better substantiated. To reliably quantify total and differential both drainage and settlement
characteristics of the tailings, the Licensee should test actual tailings specimens from the site.
Drainage/seepage/dewatering analyses performed should reflect the tailings and drainage conditions
(including drainage system) associated with each particular cell. One or more cross-sections may need
to be considered. Due to uncertainty and/or inherent variability of the tailings materials, multiple
analyses bracketing the ranges of anticipated engineering properties should be performed.
Contingencies for less-than-most-likely performance should be incorporated into the design of the cover
system. Particular consideration should be given to variations in the magnitude of differential settlement
as well as the time required to reach 90% consolidation. In light of the particularly large range in the
coefficients of consolidation already presented by the Licensee, it can be misleading to cite or use
“average” values when discussing or planning other activities (for example, see the monitoring section of
the report (sub-Appendix I of Appendix D) which states, “a monitoring period of four years prior to final
cover system construction is anticipated, based on the estimated time required to reach 90 percent
consolidation.” All references to settlement magnitude, rate, and duration should be provided as ranges.
Given the erratic nature exhibited in the existing settlement monitoring data, it is recommended that the
monitoring process be reviewed and revised to assure greater accuracy. As a minimum, the data should
be reviewed as soon as it is gathered and its quality be checked by plotting it with previous data and
making certain that the data makes sense (i.e., is consistent with expected trends; not showing significant
amounts of upward displacement, for example). Questionable data should be confirmed or replaced with
new measurements. Without such quality control measures, it may become difficult or impossible to
demonstrate that 90% consolidation has been reached and that cover materials can be placed.
It is suggested that statements such as the following from page I-2 of sub-Appendix I of Appendix D:
“typically less than 0.1 feet (30 mm) of cumulative settlement over a 12 month period is acceptable” be
avoided because such statements might be mistakenly substituted for the real requirement of 90%
consolidation.
The Licensee’s assessment of settlement only addresses primary settlement and does not consider
secondary settlement effects (i.e., creep) or seismically-induced settlement of the tailings. Secondary
settlement and seismically induced settlement of the tailings (if any) and their subsequent effects on the
cover system should be assessed. Assessment of settlement under seismic conditions is dependent upon
the Licensee’s seismic hazard analysis. Any revisions to the seismic hazard analysis may necessitate
revisions to such an assessment.
August 15, 2012
Interrogatory 07/1: R313-24-4; 10CFR40.Appendix A, Criterion 4: Technical Analysis – Settlement and Potential for Cover Slope Reversal and/or
Cover Layer Cracking Page 49 of 117
NUREG-1620 (NRC 2003), Section 2.3.3, specifies that: “The analysis of tailings settlement will be
acceptable if it meets the following criteria:
(1) Computation of immediate settlement follows the procedure recommended in NAVFAC DM–7.1
(Department of the Navy, 1982). If a different procedure is used, the basis for the procedure is
adequately explained. The procedure recommended in NAVFAC DM–7.1 (Department of the Navy,
1982) for calculation of immediate settlement is adequate if applied incrementally to account for
different stages of tailings emplacement. If this method is used, the reviewer should verify that the
computation of incremental tailings loading and the width of the loaded area, as well as the
determination of the undrained modulus and Poisson’s ratio, have been computed and documented.
Settlement of tailings arises from compression of soil layers within the disposal cell and in the
underlying materials. Because compression of sands occurs rapidly, compression of sand layers in
the disposal cell and foundations must be considered in the assessment of immediate settlement.
However, the contribution of immediate settlement to consolidation settlement cannot be ignored.
Clay layers and slime undergo instantaneous elastic compression controlled by their undrained
stiffness as well as long-term inelastic compression controlled by the processes of consolidation and
creep (NRC, 1983a).
(2) Each of the following is appropriately considered in calculating stress increments for assessment
of consolidation settlement:
(a) Decrease in overburden pressure from excavation
(b) Increase in overburden pressure from tailings emplacement\
(c) Excess pore-pressure generated within the disposal cell
(d) Changes in ground-water levels from dewatering of the tailings
(e) Any change in ground-water levels from the reclamation action
(3) Material properties and thicknesses of compressible soil layers used in stress change and volume
change calculations for assessment of consolidation settlement are representative of in situ
conditions at the site.
(4) Material properties and thicknesses of embankment zones used in stress change and volume
change calculations are consistent with as-built conditions of the disposal cell.
(5) Values of pore pressure within and beneath the disposal cell used in settlement analyses are
consistent with initial and post-construction hydrologic conditions at the site.
(6) Methods used for settlement analyses are appropriate for the disposal cell and soil conditions at
the site. Contributions to settlement by drainage of mill tailings and by consolidation/compression of
slimes and sands are considered. Both instantaneous and time-dependent components of total and
differential settlements are appropriately considered in the analyses (NRC, 1983a,b,c). The
procedure recommended in NAVFAC DM–7.1 (Department of the Navy, 1982) for calculation of
secondary compression is adequate.
(7) The disposal cell is divided into appropriate zones, depending on the field conditions, for
assessment of differential settlement, and appropriate settlement magnitudes are calculated and
assigned to each zone.
August 15, 2012
Interrogatory 07/1: R313-24-4; 10CFR40.Appendix A, Criterion 4: Technical Analysis – Settlement and Potential for Cover Slope Reversal and/or
Cover Layer Cracking Page 50 of 117
(8) Results of settlement analyses are properly documented and are related to assessment of overall
behavior of the reclaimed pile.
(9) An adequate analysis of the potential for development of cracks in the radon/infiltration barrier
as a result of differential settlements is provided (Lee and Shen, 1969).”
REFERENCES
DOE (U.S. Department of Energy). 1989. Technical Approach Document, Revision II. UMTRA-DOE/AL
050425.0002.
EPA (U.S. Environmental Protection Agency). 1989. Final Covers on Hazardous Waste Landfills and
Surface Impoundments, Technical Guidance Document, EPA/530-SW-89-047, Office of Solid Waste and
Emergency Response, Washington, D.C. URL:
http://webcache.googleusercontent.com/search?q=cache:VEVCaJfyPDQJ:nepis.epa.gov/Exe/ZyPURL.cg
i%3FDockey%3D100019HC.txt+site:epa.gov+EPA+Final+Covers+Guidance&cd=4&hl=en&ct=clnk
&gl=us.
EPA 1991. Seminar Publication, Design and Construction of RCRA/CERCLA Final Covers. EPA/625/4-
91/025.May 1991, 208 pp.
EPA 2004. (Draft) Technical Guidance for RCRA/CERCLA Final Covers. U.S EPA 540-R-04-007,
OSWER 9283.1-26. April 2004, 421 pp. URL: nepis.epa.gov/Exe/ZyPURL.cgi?Dockey=P10074PP.txt.
U.S. Nuclear Regulatory Commission 2003. “Standard Review Plan (NUREG–1620) for Staff Reviews of
Reclamation Plans for Mill Tailings Sites Under Title II of The Uranium Mill Tailings Radiation Control
Act”, NUREG-1620, June, 2003.
August 15, 2012
Interrogatory 08/1: R313-24-4; 10CFR40.Appendix A, Criterion 4: Technical Analysis – Erosion Stability Evaluation Page 51 of 117
INTERROGATORY WHITEMESA RECPLAN REV5.0 R313-24-4; 10CFR40 APPENDIX A
CRITERION 4; INT 08/1: TECHNICAL ANALYSIS –EROSION STABILITY EVALUATION
REGULATORY BASIS:
UAC R313-24-4 invokes the following requirement from 10CFR40, Appendix A, Criterion 4: “The
following site and design criteria must be adhered to whether tailings or wastes are disposed of above or
below grade:
… (c) Embankment and cover slopes must be relatively flat after final stabilization to minimize erosion
potential and to provide conservative factors of safety assuring long-term stability. The broad objective
should be to contour final slopes to grades which are as close as possible to those which would be
provided if tailings were disposed of below grade; this could, for example, lead to slopes of about 10
horizontal to 1 vertical (10h:1v) or less steep. In general, slopes should not be steeper than about 5h:1v.
Where steeper slopes are proposed, reasons why a slope less steep than 5h:1v would be impracticable
should be provided, and compensating factors and conditions which make such slopes acceptable should
be identified.
(d) A full self-sustaining vegetative cover must be established or rock cover employed to reduce wind and
water erosion to negligible levels.
Where a full vegetative cover is not likely to be self-sustaining due to climatic or other conditions, such as
in semi-arid and arid regions, rock cover must be employed on slopes of the impoundment system. The
Executive Secretary will consider relaxing this requirement for extremely gentle slopes such as those
which may exist on the top of the pile.
The following factors must be considered in establishing the final rock cover design to avoid
displacement of rock particles by human and animal traffic or by natural process, and to preclude
undercutting and piping:
• Shape, size, composition, and gradation of rock particles (excepting bedding material average
particles size must be at least cobble size or greater);
• Rock cover thickness and zoning of particles by size; and
• Steepness of underlying slopes.
Individual rock fragments must be dense, sound, and resistant to abrasion, and must be free from cracks,
seams, and other defects that would tend to unduly increase their destruction by water and frost actions.
Weak, friable, or laminated aggregate may not be used.
Rock covering of slopes may be unnecessary where top covers are very thick (or less); bulk cover
materials have inherently favorable erosion resistance characteristics; and, there is negligible drainage
catchment area upstream of the pile and good wind protection as described in points (a) and (b) of this
criterion.
Furthermore, all impoundment surfaces must be contoured to avoid areas of concentrated surface runoff
or abrupt or sharp changes in slope gradient. In addition to rock cover on slopes, areas toward which
surface runoff might be directed must be well protected with substantial rock cover (rip rap). In addition
to providing for stability of the impoundment system itself, overall stability, erosion potential, and
August 15, 2012
Interrogatory 08/1: R313-24-4; 10CFR40.Appendix A, Criterion 4: Technical Analysis – Erosion Stability Evaluation Page 52 of 117
geomorphology of surrounding terrain must be evaluated to assure that there are not ongoing or
potential processes, such as gully erosion, which would lead to impoundment instability.

INTERROGATORY STATEMENT:
Refer to Section 3.3.5 of the Reclamation Plan, Rev. 5.0 and Section 4.9 and Appendix G to Appendix
D (Updated Tailings Cover Design Report), and Drawings TRC-1 through TRC-8 to the Reclamation
Plan, Rev. 5.0: Please provide the following:
1. To further confirm the appropriateness and currency of the calculated Probable Maximum
Precipitation (PMP) value and as used, for example, in the ET cover design erosion protection
rock rip rap sizing calculations, please provide a revised PMP calculation updating the PMP
distribution that incorporates information from the following documents, in addition to HMR 49
(Hansen et al.1984):
• “2002 Update for Probable Maximum Precipitation, Utah 72 Hour Estimates to 5,000
sq. mi”. – March 2003 Jensen 2003); and
• “Probable Maximum Precipitation Estimates for Short Duration, Small Area Storms in
Utah” – October 1995 (Jensen 1995)
Response 1 (May 31, 2012 and August 15, 2012):
The local-storm Probable Maximum Precipitation (PMP) events used to calculate the
peak discharges for evaluation of erosional stability were the six-hour duration PMP
(with a precipitation total of 10.0 inches) and the one-hour duration PMP (with a
precipitation total of 8.3 inches). These events were determined for the site area using
HMR No. 49 (Hansen et al. 1984). These PMP values were evaluated for
appropriateness using the two references listed above by Jensen (1995 and 2003) and
the updated calculations were provided as Attachment B of the May 31, 2012 response.
The updated PMP values are 8.3 and 9.6 for the one-hour and six-hour duration PMP,
respectively.

2. Using the revised PMP information obtained from Item 1 above, provide revised calculations of
required rock rip rap sizes for the cover sideslope areas using the updated method developed for
round-shaped rip rap as described in Abt et al. 2008. Update and revise other erosion protection
calculation presented in Appendix G, as required and appropriate, to reflect the revised PMP
determination.
Response 2 (August 15, 2012):
This response supersedes the response provided in the previous response document
dated May 31, 2012.
There are no modifications required to the erosion protection calculations as a result of
updating the PMP calculations.
The procedure provided in Abt et al. (2008) has not been approved or adopted by the
NRC for sizing round-shaped riprap (personal communication with Dr. Steven Abt on
May 12, 2012). The latest NRC guidance for sizing round-shaped riprap is the method
presented in Abt and Johnson (1991) and referenced in NUREG-1623 (NRC, 2002).
The erosional stability analyses have been updated to incorporate the use of angular
rock on the embankments, as well as to revise the riprap sizing on the embankment
slopes for non-accumulating flows. The results of the analyses are provided in
August 15, 2012
Interrogatory 08/1: R313-24-4; 10CFR40.Appendix A, Criterion 4: Technical Analysis – Erosion Stability Evaluation Page 53 of 117
Attachment C as a revised Appendix G that will be included in the next version of the
Updated Tailings Cover Design Report (Appendix D of the Reclamation Plan).
References for Response 2 (May 31, 2012 and August 15, 2012):
Abt, S., 2012. Personal communication from Steven Abt, Colorado State University, to
Melanie Davis, MWH Americas, Inc., May 12.
Abt, S., and Johnson, T. 1991. Riprap Design for Overtopping Flow, Journal of
Hydraulic Engineering, Vol. 117, No. 8, August.
U.S. Nuclear Regulatory Commission (NRC), 2002 “Design of Erosion Protection for
Long-Term Stability”, NUREG-1623, September.
3. Please provide additional calculations to estimate the magnitude and location of a potential gully
intrusion into each soil-covered portion of the proposed cover system (e.g., using the procedure
described in Thornton and Abt 2008). Demonstrate that excluding rock (gravel) particles from
the currently proposed flattest (0.1 % and 0.5%) top slope areas would adequately protect
against sheet flow under potential precipitation conditions and would adequately control longer-
term rill and/or gully initiation and development. Provide information on required “overdesign”
of the cover thickness needed to accommodate maximum predicted gully depths and locations.
Response 3 (May 31, 2012 and August, 15, 2012):
The gully intrusion analysis procedure described in Thornton and Abt (2008), as well as
the precursor gully analysis procedure developed by Abt and documented in Appendix B
of NUREG-1623 (NRC, 2002) are intended for soil-covered embankment slopes. The
procedure is not applicable to the flatter top slope only (personal communication with Dr.
Steven Abt on May 12, 2012). The top slopes have been designed to meet erosional
stability using the Temple method as presented in Appendix A of NUREG-1623 (NRC,
2002). Gully intrusion analysis was not conducted for the side slopes which have been
designed with rock protection.
References for Response 3 (May 31, 2012 and August 15, 2012):
Abt, S., 2012. Personal communication from Steven Abt, Colorado State University, to
Melanie Davis, MWH Americas, Inc., May 12.
Thornton, C., and Abt, S., 2008. “Gully Intrusion into Reclaimed Slope: Long-Term
Time-Average Calculation Procedure”, Journal of Energy Engineering, Vol. 134, No. 1,
March 2008, pp. 15-23.
U.S. Nuclear Regulatory Commission (NRC), 2002 “Design of Erosion Protection for
Long-Term Stability”, NUREG-1623, September.

4. Provide additional detailed cross sections showing every interface that will occur between
sidelope cover layers and topslope cover layers. Demonstrate that all applicable filter criteria
will be met for each interface between each topslope cover layer component and the proposed
granular filter layer on the sideslope, including standard filter gradation criteria as well as
applicable permeability filter criteria (e.g., for filter layer underlying riprap on sideslope areas).
Consider filter criteria for preventing migration of granular materials into an adjacent coarser
grained granular layer (e.g., Nelson et al. 1986, Equation 4.35); for preventing piping of finer
grained cohesionless soil particles into an adjacent coarser-grained material layer (e.g.,
Cedegren 1989, Equation 5.3); and for preventing erosion of a finer-grained material layer from
occurring over the long term as a result of flows in an adjacent coarser (filter zone) layer (e.g.,
August 15, 2012
Interrogatory 08/1: R313-24-4; 10CFR40.Appendix A, Criterion 4: Technical Analysis – Erosion Stability Evaluation Page 54 of 117
Nelson et al. 1986, Equation 4.36). Include consideration of different specific filter stability
criteria (e.g., NRCS 1994, Tables 26-1 and 26-2) for determining the maximum allowable D15 of
a granular filter layer material for preventing erosion of any adjacent layer (e.g., sacrificial soil
layer) consisting of fine-grained/finer-grained particles, as a function of soil type. Address
applicable filter permeability criteria for the filter layer in the sideslope cover system, including
Table 26-3 of NRCS 1994.
Response 4 (August 15, 2012):
This response supersedes the response provided in the previous response document
dated May 31, 2012.
The Drawings will be revised to show include the filter and riprap layers. The filter
gradation requirements were determined using NRCS (1994) as documented in
Appendix G of Appendix D of the Reclamation Plan. These filter material gradation
requirements were updated based on the results of laboratory tests conducted on
additional samples of cover borrow material collected in April, 2012. The results are
provided in Attachment C. The procedure from NRCS (1994) was used to determine the
filter gradation limits. In addition, criteria provided in Nelson et al. (1986) and Cedegren
(1989) were evaluated for the filter gradation limits.

Reference for Response 4 (August 15, 2012):
Cedegren, H.R., 1989. Seepage, Drainage, and Flow Nets. Equation 5.3. 3rd Edition.
John Wiley & Sons, Inc., New York.
Natural Resource Conservation Service (NRCS), 1994. Gradation Design of Sand and
Gravel Filters, U.S. Department of Agriculture, National Engineering Handbook,
Part 633, Chapter 26, October.
Nelson, J., S. Abt, R. Volpe, D. van Zyl, N. Hinkle, and W. Staub, 1986. "Methodologies
for Evaluation of Long-term Stabilization Designs of Uranium Mill Tailings
Impoundments." NUREG/CR-4620, U.S. Nuclear Regulatory Commission, June.

5. Provide revised cover system cross sections to include a thicker riprap layer on the cover
sideslope areas (i.e., minimum thickness of 1.5 times the D50 of the rock rip size of 7.4 inches, or
the D100 of the rock rip rap materials, whichever is greater) to bring the cover design into
compliance with recommendations contained in Section 2.1.2 of NUREG-1623 (NRC 2002).
Response 5 (August 15, 2012):
This response supersedes the response provided in the previous response document
dated May 31, 2012.
The Drawings will be updated to show a minimum thickness of 1.5 times the D50 of the
rock riprap size, or the D100 whichever is greater. The drawing updates will be included
in the next revision of the Reclamation Plan after approval of the final cover design.

6. Provide revised construction drawings for the final cover that preclude the presence of low areas
that have the potential for experiencing future concentrated flows (e.g., portion of cover overlying
Cell 2 as depicted on Section B-3 on Drawing TRC-7) and that avoid areas having abrupt
changes in slope gradient across the cells, (e.g., areas of cover having proposed 5h:1v slopes
August 15, 2012
Interrogatory 08/1: R313-24-4; 10CFR40.Appendix A, Criterion 4: Technical Analysis – Erosion Stability Evaluation Page 55 of 117
shown on Sections B-3 and C-3 on Drawings TRC-6 and TRC-7 and Detail 7/8 on Drawing TRC-
8, etc..) to be consistent with UAC R313-24-4 10CFR40, Appendix A, Criterion 4.
Response 6 (May 31, 2012):
This response supersedes the response provided in the previous response document
dated May 31, 2012.
Section B-3 on Drawing TRC-7 will be revised to show the correct direction of the 0.5
percent slope to be toward the south to match the plan view shown on Drawing TRC-3.
The 5H:1V slopes shown on the cover top slope will be revised to be 10H:1V. The
drawing updates will be included in the next revision of the Reclamation Plan after
approval of the final cover design.

BASIS FOR INTERROGATORY:
When determining the PMP for facilities such as High Hazard and Moderate Hazard dams, the State of
Utah currently requires the use of HMR 49, which DUSA has used in Attachment G to the Reclamation
Plan 4.0 (Denison 2009) and referenced in Appendix D to the Reclamation Plan 5.0 (Denison 2011), but
also in conjunction with the use of two other reports: (1) the “2002 Update for Probable Maximum
Precipitation, Utah 72 Hour Estimates to 5,000 sq. mi. – March 2003” and (2) “Probable Maximum
Precipitation Estimates for Short Duration, Small Area Storms in Utah – October 1995.” Although these
two methods were developed (by the Utah Climate Center) for estimating PMF conditions for design of
dams, these methods are considered to be more representative of actual meteorological conditions in
Utah than those considered in HMR 49. The erosion protection calculations presented in Appendix G
(Erosion Stability Evaluation) should to be revised as needed to reflect the revised PMP determination
findings, as appropriate, to demonstrate that applicable erosion protection requirements will be met.
The Modified Universal Soil Loss Equation (MUSLE) was used (Appendix G to Appendix D to the
Reclamation Plan) to evaluate erosion losses from the topslope areas of the cover due to sheet flow but
does not consider the potential for gully development or intrusion due to the topographic features of the
tailings area which are assumed to remain constant with time (Nelson 1986).
Although the Temple method (Appendix D) was appropriately used to evaluate the erosional stability of
portions of the cover comprised of “topsoil and vegetation” and “topsoil mixed with gravel” –covered
slopes, the method assumes only minor channeling, gullying, or rilling. Due to the relatively large and
flat nature of the currently proposed topslope areas, these assumptions may or may not reflect actual
conditions that are expected to occur. It is possible that less or more severe flow concentrations would
occur and vegetation would or would not provide significant protection. Research has demonstrated that
if localized erosion and gullying occurs, damage to unprotected soil covers may occur rapidly, probably
in a time period shorter than 200 years (NUREG-1623 [NRC 2002]). It needs to be demonstrated that all
slopes are designed to meet NUREG-1623 requirements, i.e., that “Soil slopes of a reclaimed tailings
impoundment should be designed to be stable and thus inhibit the initiation, development, and growth of
gullies.” A procedure developed by Thornton and Abt (2008), which builds upon a preliminary
procedure developed by Abt et al. 1997 (as discussed in Appendix B of NUREG-1623), provides a means
of estimating the magnitude and location of a potential gully intrusion into the flat topslope areas of the
cover.
Additional descriptive information and supporting calculations need to be provided to demonstrate that
all applicable filter criteria are met for all topslope cover/ sideslope cover layer interfaces. Acceptable
filter sizing criteria for preventing migration of the selected filter/bedding materials into the riprap and
for minimizing or preventing erosion of the soil layer below the filter/bedding layer, and for meeting filter
August 15, 2012
Interrogatory 08/1: R313-24-4; 10CFR40.Appendix A, Criterion 4: Technical Analysis – Erosion Stability Evaluation Page 56 of 117
permeability criteria are described in NUREG/CR-4620 (Nelson et al. 1986), Cedegren 1989 and NCRS
1994.
In addition, currently, it is unclear from Drawings TRC-1 through TRC-8 of the Reclamation Plan Rev.
5.0 as to whether filter blankets or bedding layers are or are not included in some areas, for example,
areas along toes of slopes, transition areas, diversion ditches and channels, stilling areas, and flow
impact areas, which are typically areas described in NUREG-1623 as areas where filters are generally
recommended. A demonstration of long-term layer stability is needed to justify the omission of a
filter/bedding blanket in the final cover system and in any such areas.
Cross sections TRC-6 and TRC-7 provided in the Reclamation Plan Rev. 5.0 depict abrupt slope changes
in the tailings cover when crossing Cell 2 to Cell 1 and Cell 2 to Cell 3. The cross sections should be
revised to meet the above UAC R313-24-4, 10CFR40, Appendix A, Criterion 4 “….all impoundment
surfaces must be contoured to avoid areas of concentrated surface runoff or abrupt or sharp changes in
slope gradient.”
NUREG-1623 (NRC 2002), Section 2.1.2 recommends that the minimum required thickness of a rock
riprap layer be no less than 1.5 times the D50 of the rock riprap materials, or the D100 of the rock rip rap
materials, whichever is greater.

REFERENCES:
Abt, S.R., Thornton, C.I., Batka, J.H., and Johnson, T.L. 1997. “Investigation of Gully Stabilization
Methods with Launching Stone: Pilot Laboratory Tests” Prepared for the U.S. Nuclear Regulatory
Commission, Washington, D.C. February 1997.
Abt, S.R., Thornton, C.I., Gallegos, H., and Ullmann, C. 2008. “Round-Shaped Riprap Stabilization in
Overtopping Flow,” Journal of Hydraulic Engineering, Vol. 134, No. 8, August 2008, pp. 1035–1041.
Bertram, G.E. 1940. An Experimental Investigation of Protective Filters. Graduate School of
Engineering, Harvard University, Cambridge, Massachusetts. Soil Mechanics Series No. 7. pp. 1-21.
Cedegren.H.R. 1989. Seepage, Drainage, and Flow Nets. 3rd Edition. John Wiley $ & Sons, Inc., New
York, NY.
Denison Mines (USA) Corporation. 2011. Reclamation Plan, Revision 5.0, White Mesa Mill, Blanding,
Utah, September 2011.
Hansen, E., Schwarz, F., and Riedel, J. 1984. Probable Maximum Precipitation Estimates, Colorado
River and Great Basin Drainages. Hydrometeorological Report No. 49. U.S Department of Commerce,
National Oceanic and Atmospheric Administration, Reprinted 1984.
Jensen, D. 1995. 2002 Update for Probable Maximum Precipitation, Utah 72 Hour Estimates to 5,000 sq.
mi. - March 2003. Utah Climate Center.
Jensen, D. 2003. Probable Maximum Precipitation Estimates for Short Duration, Small Area Storms in
Utah - October 1995. Utah Climate Center.
Nelson, J.D., Abt, S.R., Volpe, R.L, van Zyl, D., Hinkle, N.E., and Staub, W.P. 1986. Methodologies for
Evaluating Long-Term Stabilization Designs of Uranium Mill Tailings Impoundments. Prepared for
August 15, 2012
Interrogatory 08/1: R313-24-4; 10CFR40.Appendix A, Criterion 4: Technical Analysis – Erosion Stability Evaluation Page 57 of 117
Nuclear Regulatory Commission, Washington, DC. NUREG/CR-4620, ORNL/TM-10067. June 1986, 151
pp.
NRC 2002. U.S. Nuclear Regulatory Commission, “Design of Erosion Protection for Long-Term
Stability”, NUREG-1623, September 2002.
NRCS (Natural Resources Conservation Service) 1994. U.S. Department of Agriculture, Part 633,
National Engineering Handbook, Chapter 26: Gradation Design of Sand and Gravel Filters. October
1994.
Thornton, C., and Abt, S. 2008. “Gully Intrusion into Reclaimed Slope: Long-Term Time-Average
calculation Procedure”, Journal of Energy Engineering, Vol. 134, No. 1, March 2008, pp. 15-23.
August 15, 2012
Interrogatory 09/1: R313-24-4; 10CFR40.Appendix A, Criterion 1: Liquefaction Page 58 of 117
INTERROGATORY WHITEMESA RECPLAN REV. 5.0; R313-24-4; 10CFR40 APPENDIX A
CRITERION 1; INT 09/1: LIQUEFACTION
REGULATORY BASIS
UAC R313-24-4 invokes the following requirement from 10CFR40 Appendix A, Criterion 1: The general
goal or broad objective in siting and design decisions is permanent isolation of tailings and associated
contaminants by minimizing disturbance and dispersion by natural forces, and to do so without ongoing
maintenance. For practical reasons, specific siting decisions and design standards must involve finite
times (e.g., the longevity design standard in Criterion 6). The following site features which will contribute
to such a goal or objective must be considered in selecting among alternative tailings disposal sites or
judging the adequacy of existing tailings sites:
• Remoteness from populated areas;
• Hydrologic and other natural conditions as they contribute to continued immobilization and
isolation of contaminants from ground-water sources; and
• Potential for minimizing erosion, disturbance, and dispersion by natural forces over the long
term.
…While isolation of tailings will be a function of both site and engineering design, overriding
consideration must be given to siting features given the long-term nature of the tailings hazards.
Tailings should be disposed of in a manner that no active maintenance is required to preserve conditions
of the site.
INTERROGATORY STATEMENT:
Refer to Section 4.8 and Appendices C and F to the Appendix D, Updated Tailings Cover Design
Report of the Reclamation Plan, Rev. 5:
1. Provide revised liquefaction analyses that rely upon actual site-specific data for the tailings
materials, rather than assumed parameters. In doing so, revise the Reclamation Plan to correctly
and defensibly characterize tailings properties consistent with these revisions throughout the
document.
Response 1 (August 15, 2012):
This response supersedes the response provided in the response document submitted
May 31, 2012.
The liquefaction analyses were revised to be applicable for long-term steady-state pore
pressure conditions within the tailings, and are consistent with regards to the tailings
dewatering analyses. The revised analyses also incorporate the update to the previous
seismic study (provided as Attachment A to the May 31, 2012 response document). The
weight of the cover system has also been included in the analyses.
A constant Standard Penetration Test (SPT) blow count (n-value) of 2 blows in 12 inches
(uncorrected) was assumed for the tailings zones that will remain saturated under long-
term steady state conditions. An uncorrected n-value of 2 is considered to be a
reasonable “lower-bound” estimate of the uncorrected blow counts for saturated tailings
based upon a comparison with similar uranium tailings at other sites, and is a more
conservative assumption than was used in previous analyses. Previous analyses
assumed a constant n-value of 4 to represent the in-situ state of the tailings.
August 15, 2012
Interrogatory 09/1: R313-24-4; 10CFR40.Appendix A, Criterion 1: Liquefaction Page 59 of 117

Unsaturated tailings zones are not be susceptible to liquefaction and were not included
in the analyses. The long-term dry density of the tailings was revised to be 90 pcf to be
consistent with the value used for the updated radon emanation analyses. The revised
liquefaction analyses are provided as Attachment F and summarized in the Table 1.
The computed factors of safety against liquefaction range from 1.76 to 2.28. Based on
these results, the tailings are judged not considered to be susceptible to earthquake-
induced liquefaction during the design seismic event.
Table 1. Summary of Liquefaction Results
Depth from
Top of Cover
(ft)
Saturated
Thickness (ft) CSR CRR7.5 MSF
Factor of
Safety
Cell 2
31.7 0 0.113 0.096 1.77 1.90
34.7 3 0.109 0.096 1.77 1.83
37.7 6 0.104 0.095 1.77 1.79
40.7 9 0.099 0.095 1.77 1.77
43.7 12 0.095 0.095 1.77 1.76
Cell 3
37.0 0 0.085 0.095 1.77 1.97
40.0 3 0.087 0.095 1.77 1.93
43.0 6 0.088 0.095 1.77 1.91
46.0 9 0.088 0.094 1.77 1.90
49.0 12 0.087 0.094 1.77 1.91
Cells 4A/4B
12.0 0.33 0.097 0.099 1.77 1.82
15.0 0.33 0.096 0.099 1.77 1.82
18.0 0.33 0.095 0.098 1.77 1.83
21.0 0.33 0.094 0.097 1.77 1.83
24.0 0.33 0.093 0.097 1.77 1.84
27.0 0.33 0.092 0.096 1.77 1.86
30.0 0.33 0.090 0.096 1.77 1.88
33.0 0.33 0.089 0.095 1.77 1.90
36.0 0.33 0.087 0.095 1.77 1.94
39.0 0.33 0.084 0.095 1.77 1.99
42.0 0.33 0.082 0.094 1.77 2.05
45.0 0.33 0.079 0.094 1.77 2.12
48.0 0.33 0.076 0.094 1.77 2.19
51.0 0.33 0.073 0.094 1.77 2.28

August 15, 2012
Interrogatory 09/1: R313-24-4; 10CFR40.Appendix A, Criterion 1: Liquefaction Page 60 of 117
2. Correct apparent errors and conduct revised analyses using parameter values that are based on
site-specific data. Correct discrepancies between calculated results and summarized, reported
results.
Response 2 (May 31, 2012 and August 15, 2012):
See Response 1.

3. Demonstrate that conditions assumed for liquefaction analyses are consistent with or
conservative compared to results of tailings dewatering analyses. If this is not true, revise
liquefaction analyses to be consistent with or conservative compared to results of tailings
dewatering analyses, report results, and demonstrate that impoundments will remain stable with
regard to liquefaction.
Response 3 (August 15, 2012):
This response supersedes the response provided in the response document submitted
May 31, 2012.
The revised liquefaction analyses are consistent with regards to the tailings dewatering
analyses.

BASIS FOR INTERROGATORY
NUREG-1620 (NRC 2003), Section 2.2.3, specifies the following with respect to slope stability analyses and
assessment of liquefaction potential: “…The analysis of slope stability will be acceptable if it meets the
following criteria:
…(3) Appropriate analyses considering the effect of seismic ground motions on slope stability are presented.
…(j) Where there is potential for liquefaction, changes in pore pressure from cyclic loading are considered in
the analysis to assess the effect of pore pressure increase on the stress-strain characteristics of the soil and
the post-earthquake stability of the slopes. Liquefaction potential is reviewed using Section 2.4 of this review
plan. Evaluations of dynamic properties and shear strengths for the tailings, underlying foundation material,
radon barrier cover, and base liner system are based on representative materials properties obtained
through appropriate field and laboratory tests (NRC 1978, 1979)….
NUREG-1620 (NRC 2003), Section 2.4.3, specifies that: “The analysis of the liquefaction potential will
be acceptable if the following criteria are met:
(1) Applicable laboratory and/or field tests are properly conducted (NRC, 1978, 1979; U.S. Army Corps
of Engineers, 1970, 1972).

(2) Data for all relevant parameters for assessing liquefaction potential are adequately collected and the
variability has been quantified.

(3) Methods used for interpretation of test data and assessment of liquefaction potential are consistent
with current practice in the geotechnical engineering profession (Seed and Idriss, 1971, 1982;
National Center for Earthquake Engineering Research, 1997). An assessment of the potential adverse
effects that complete or partial liquefaction could have on the stability of the embankment may be
based on cyclic triaxial test data obtained from undisturbed soil samples taken from the critical zones
August 15, 2012
Interrogatory 09/1: R313-24-4; 10CFR40.Appendix A, Criterion 1: Liquefaction Page 61 of 117
in the site area (Seed and Harder, 1990; Shannon & Wilson, Inc. and Agbabian-Jacobsen Associates,
1972).

(4) If procedures based on laboratory tests combined with ground response analyses are used,
laboratory test results are corrected to account for the difference between laboratory and field
conditions (NRC, 1978; Naval Facility Engineering Command, 1983).

(5) The time history of earthquake ground motions used in the analysis is consistent with the design
seismic event.

(6) If the potential for complete or partial liquefaction exists, the effects such liquefaction could have on
the stability of slopes and settlement of tailings are adequately quantified.

(7) If a potential for global liquefaction is identified, mitigation measures consistent with current
engineering practice or redesign of tailings ponds/embankments are proposed and the proposed
measures provide reasonable assurance that the liquefaction potential has been eliminated or
mitigated.

(8) If minor liquefaction potential is identified and is evaluated to have only a localized effect that may
not directly alter the stability of embankments, the effect of liquefaction is adequately accounted for
in analyses of both differential and total settlement and is shown not to compromise the intended
performance of the radon barrier. Additionally, the disposal cell is shown to be capable of
withstanding the liquefaction potential associated with the expected maximum ground acceleration
from earthquakes. The licensee may use post-earthquake stability methods (e.g., Ishihara and
Yoshimine, 1990) based on residual strengths and deformation analysis to examine the effects of
liquefaction potential. Furthermore, the effect of potential localized lateral displacement from
liquefaction, if any, is adequately analyzed with respect to slope stability and disposal cell integrity.

The liquefaction analysis presented by the Licensee is based on the procedures presented in Youd et al.
(2001). While newer methods have been introduced and are being used, this method is still an
acceptable, state-of-practice method provided that borderline finer-grained soils are appropriately
assessed (see Boulanger and Idriss, 2006; Bray and Sancio, 2006; Boulanger and Idriss, 2011). Aside
from the earthquake magnitude and ground acceleration, the most important parameter in the analysis is
the in-situ penetration resistance parameter (which in this case is an SPT blowcount) which provides a
measure of the soil’s resistance to liquefaction. In the Licensee’s analysis, this SPT blowcount has been
assumed to be 4 without any substantial justification – the justification provided in the report is that the
analyst considered the tailings to be “loose” and that such a term is often correlated with a blowcount in
the range of 4 to 10. However, it seems that analyst could have alternatively assumed that the tailings
were “very loose,” leading to a blowcount in the range of 0 to 4, thus significantly affecting the outcome
of the analysis. Also, elsewhere in the report (when approximating the shear strength of the drained
tailings), the Licensee assumes that the tailings have a relative density of near zero, and a relative density
of zero and a blow count of 4 are typically inconsistent.
A similar issue with consistency appears to exist in the characterization of the tailings’ unit weight where
dry and saturated unit weights of 86.3 and 117.1 pcf, respectively, are presented in Section F.2.2 of sub-
Appendix F in Appendix D of the Reclamation Plan, Rev. 5.0, whereas a dry unit weight of 74.3 pcf is
presented in Section C.2.4 of sub-Appendix C of Appendix D). Consistent characterization of the tailings
throughout the report seems to be needed, and more importantly, with respect to liquefaction, a more
substantiated blowcount describing the tailings is needed. If data doesn’t exist, it must be collected, not
manufactured.
August 15, 2012
Interrogatory 09/1: R313-24-4; 10CFR40.Appendix A, Criterion 1: Liquefaction Page 62 of 117
It is noted that the results presented in Table F.5 ‘Summary of Liquefaction Results’ do not agree with the
calculated values shown in Attachment F.3. Further, it appears from the text that the Licensee intended
to have the cover in place for the analysis (the Licensee should clearly explain the configuration of the
impoundment and tailings reflected in the calculations); however, the weight of the cover seems to have
been omitted from the calculated total and effective vertical stresses. Also, if the depth parameter “z” in
the calculations is intended to reference from the top of the tailings as the datum, and given the stated
“depth from top of tailings to water surface”, it appears that effective stresses have been calculated
incorrectly. Calculation of the overburden correction factor should also be checked.
Assessment of liquefaction is dependent upon the Licensee’s seismic hazard analysis. Any revisions to the
seismic hazard analysis may necessitate revisions to this assessment. Also, the applicability of the
liquefaction hazard analysis is dependent upon the outcome of tailings dewatering analyses, and the
Licensee should demonstrate that the results such analyses are appropriately interpreted (i.e., are at least
consistent with, if not conservative) for the liquefaction hazard analysis.

REFERENCES
Boulanger, R.W. and Idriss, I.M. (2006). “Liquefaction susceptibility criteria for silts and clays.” J. of
Geotechnical and Geoenvironmental Eng., ASCE, Vol. 132, No. 11, pp. 1413-1426.
Bray, J.D. and Sancio, R.B. (2006). “Assessment of the liquefaction susceptibility of fine grained soils.”
J. of Geotechnical and Geoenvironmental Eng., ASCE, Vol. 132, No. 9, pp. 1165-1177.
Boulanger, R.W. and Idriss, I.M. (2011). “Cyclic failure and liquefaction: Current issues.” Proc. Fifth
International Conf. of Earthquake Geotechnical Eng., Santiago, Chile.
MWH Americas 2011. Appendix C - Radon Emanation Modeling, and Appendix F – Settlement and
Liquefaction Analysis, contained in Appendix D, Updated Tailings Cover Design Report, White Mesa
Mill, September 2011 to the Reclamation Plan, White Mesa Mill, Rev. 5.0, September 2011.
NRC 1982. U.S. Nuclear Regulatory Commission, “Regulatory Guide 3.8; Preparation of Environmental
Reports for Uranium Mills”, Washington DC, October 1982.
NRC 2001. U.S. Nuclear Regulatory Commission, “Environmental Review Guidance for Licensing
Actions Associated with NMSS Programs.” Washington, DC, 2001.
NRC 2003. U.S. Nuclear Regulatory Commission, “Standard Review Plan for the Review of a
Reclamation Plan for Mill Tailings Sites Under Title II of the Uranium Mill Tailings Radiation Control
Act of 1978.” Washington DC, June 2003.
Youd, T. L., Idriss, I. M., Andrus, R. D., Arango, I., Castro, G., Christian, J. T., Dobry, R., Finn, W. D. L.,
Harder, L. F., Jr., Hynes, M. E., Ishihara, K., Koester, J. P., Liao, S. S. C., Marcuson, W. F., III, Martin,
G. R., Mitchell, J. K., Moriwaki, Y., Power, M. S., Robertson, P. K., Seed, R. B., and Stokoe, K. H., II.
(2001). “Liquefaction resistance of soils: summary report from the 1996 NCEER and 1998 NCEER/NSF
workshops on evaluation of liquefaction resistance of soils.” J. of Geotechnical and Geoenvironmental
Eng., ASCE, Vol. 127, No. 10, pp. 817-833.
August 15, 2012
Interrogatory 011/1: R313-24-4; 10CFR40.Appendix A: Vegetation and Biointrusion Evaluation and Revegetation Plan Page 63 of 117
INTERROGATORY WHITEMESA RECPLAN 5.0 R313-24-4; 10CFR40 APPENDIX A,
CRITERION 6; INT 10/1: TECHNICAL ANALYSES - FROST PENETRATION ANALYSIS
REGULATORY BASIS:
Refer to R313-25-8(4). Analyses of the long-term stability of the disposal site shall be based upon
analyses of active natural processes including erosion, mass wasting, slope failure, settlement of wastes
and backfill, infiltration through covers over disposal areas and adjacent soils, and surface drainage of
the disposal site. The analyses shall provide reasonable assurance that there will not be a need for
ongoing active maintenance of the disposal site following closure.
UAC R313-24-4 invokes the following requirement from 10CFR40, Appendix A, Criterion 6(1): “In
disposing of waste byproduct material, licensees shall place an earthen cover (or approved alternative)
over tailings or wastes at the end of milling operations and shall close the waste disposal area in
accordance with a design which provides reasonable assurance of control of radiological hazards to (i)
be effective for 1,000 years, to the extent reasonably achievable, and, in any case, for at least 200 years,
and (ii) limit releases of radon-222 from uranium byproduct materials, and radon-220 from thorium
byproduct materials, to the atmosphere so as not to exceed an average release rate of 20 picocuries per
square meter per second (pCi/m2s) to the extent practicable throughout the effective design life
determined pursuant to (1)(i) of this criterion. In computing required tailings cover thicknesses, moisture
in soils in excess of amounts found normally in similar soils in similar circumstances may not be
considered. Direct gamma exposure from the tailings or wastes should be reduced to background levels.
The effects of any thin synthetic layer may not be taken into account in determining the calculated radon
exhalation level. If non-soil materials are proposed as cover materials, it must be demonstrated that these
materials will not crack or degrade by differential settlement, weathering, or other mechanism, over long-
term intervals.”
NUREG-1620 specifies that “Reasonable assurance [shall be] provided that the requirements of 10 CFR
Part 40, Appendix A, Criterion 6(1), which requires that the design of the disposal facility provide
reasonable assurance of control of radiological hazards to be effective for 1,000 years, to the extent
reasonably achievable, and, in any case, for at least 200 years, have been met.”

INTERROGATORY STATEMENT:
Refer to Section 4.3 of Appendix D (Updated Tailings Cover Design Report) and Appendix B
(Freeze/Thaw Modeling) to Appendix D to the Reclamation Plan Rev. 5.0:

1. Please revise freeze/thaw analyses to incorporate the following:

a. Extrapolation of frost depth to recurrence interval to a minimum period of up to 1,000 years,
to the extent practicable, or, to not less than 200 years, using a Gumbel extreme statistics
(probability functions) approach (e.g., Smith and Rager 2002; Smith 1999; Yevjevich 1982).

b. Additional justification for selection of an N -factor (surface temperature correction factor)
of 0.6, instead of an N –factor of 0.7, based on published recommendations (e.g., DOE 1989).

c. Additional justification that using climate data for Grand Junction, Colorado in the Berggren
Model Formula (BMF) is representative of site conditions at the White Mesa site Address the
considerably lower elevation and average warmer temperatures of Grand Junction compared
to the White Mesa site. Either (1) prepare and report results of the BMF calculations using a
default location having an elevation and Design Freezing Index equal to or greater than
August 15, 2012
Interrogatory 011/1: R313-24-4; 10CFR40.Appendix A: Vegetation and Biointrusion Evaluation and Revegetation Plan Page 64 of 117
those of the White Mesa site AND mean average temperatures equal to or less than those of
the White Mesa site OR (2) justify that the Grand Junction data is applicable and
representative as input to the BMF calculations for the White Mesa site.
Response 1 (August 15, 2012):
This response supersedes the response provided in the response document submitted
May 31, 2012.
The freeze/thaw analyses have been revised to use Gumbel extreme statistics approach
for a time period of 200 years. The revised analyses are provided as Attachment C to
this document. An N-factor of 0.7 and climate data from the Blanding, Utah was used for
the analyses. The resulting frost penetration depth was estimated as 32 inches. The
analyses were provided as Attachment C to the May 31, 2012 response document.
The analyses will be revised after approval of the conceptual final cover design to be
consistent with the revised cover design presented the responses to Interrogatory 12/1
and Attachment H.

2. Based on the results of the revised frost penetration analysis, justify revised soil parameter values
for soils within the cover system above the projected frost penetration depth considering the
effects of repeated freezing and thawing over the recurrence interval considered (referred to in
Item 1.a above). Use these parameter values in performance assessment modeling, including
infiltration modeling and radon attenuation modeling, consistent with recommendation provided
in Sections 2.5 and 5.1 of NUREG-1620 (NRC 2003).
Response 2 (August 15, 2012):
This response supersedes the response provided in the response document submitted
May 31, 2012.
The revised infiltration and radon emanation modeling reflects potential modifications to
the hydraulic and physical properties of the cover due to freeze/thaw processes based
on recommendations provided in Benson et al. (2011). The results of the modeling are
provided as part of the second response document to the Revised ICTM Interrogatories.

Reference for Response 2 (August 15, 2012):
Benson, C.H., W.H. Albright, D.O. Fratta, J.M. Tinjum, E. Kucukkirca, S.H. Lee, J.
Scalia, P.D. Schlicht, and X. Wang, 2011. Engineered Covers for Waste
Containment: Changes in Engineering Properties and Implications for Long-Term
Performance Assessment, Volume 1 and 2, NUREG/CR-7028, Report Prepared
for the U.S. Nuclear Regulatory Commission, December.

3. If applicable after addressing the instructions stated above, revise Appendix B to Appendix D of
the Reclamation Plan to ensure that all intended text is present in the document.
Response 3 (May 31, 2012 and August 15, 2012):
Appendix B to Appendix D of the Reclamation Plan will be updated to incorporate the
revised freeze/thaw analyses for the next version of the Reclamation Plan.

August 15, 2012
Interrogatory 011/1: R313-24-4; 10CFR40.Appendix A: Vegetation and Biointrusion Evaluation and Revegetation Plan Page 65 of 117
BASIS FOR INTERROGATORY:
The Division acknowledges that the Modified Berggren Formula has been used to estimate the depth of
frost penetration at the site, relying upon input from a built-in long-term weather database. However, the
input parameters do not account for extreme climate conditions. In addition, in Appendix B, it is noted
that the mean annual temperature for Blanding given by Dames and Moore (1978) is 49.8 degrees F and
the mean annual temperature for Grand Junction, CO, is 53.1 degrees F. The Grand Junction mean
annual temperature used in the White Mesa calculations is higher, i.e, less conservative, than Blanding’s
mean temperature. Grand Junction’s elevation is also considerably lower than that of either Blanding or
the White Mesa site.
The use of a Gumbel extreme value statistics approach provides an accepted means for extrapolating a
worst case value from a limited set of data. This technical approach has been successfully applied at
other similar facilities (e.g., Monticello, Utah tailings repository cover – 200 year recurrence interval;
Crescent Junction, Utah tailings repository cover- 1,000 year recurrence interval [e.g., see NRC 2008]).
Extending the recurrence interval for the frost depth penetration analysis further informs predictions of
potential future maximum frost penetration depths and allows insights into the potential risk reduction
afforded to performance assessment predictions made for evaluating the performance of the cover system
over long term performance periods.
U.S.D.O.E. (1989), based on recommendations by the U.S. Army Corps of Engineers Cold Regions
Research and Engineering Laboratory (CRREL), and Smith (1999) recommend that an N-factor of 0.7 be
used for landfill cover designs. Additional information should therefore be provided to support the
selection and use of an N-factor value of 0.6, rather than 0.7, in the calculation, or alternatively, an N-
factor value of 0.7 should be used in the calculation.
Section numbers in Appendix B of Appendix D of the Reclamation Plan suggest that sections are missing
or that the section numbering is incorrect.

REFERENCES:
Denison Mines (USA) Corporation. 2011. Reclamation Plan, Revision 5.0, White Mesa Mill, Blanding,
Utah, Appendix D: September 2011.
NRC 2003. NUREG-1620: Standard Review Plan for the Review of a Reclamation Plan for Mill Tailings
Sites under Title II of the Uranium Mill Tailings Radiation Control Act of 1978. Washington DC, June
2003.
NRC 2008. “Summary of Changes to Moab Disposal Cell Calculations”. NRC ADAMS Website:
Document Accession Number ML081700262.
Smith, G.M., and Rager, R.E. 2002. “Protective Layer Design in Landfill Covers Based on Frost
Protection”. Journal of Geotechnical and Geoenvironmental Engineering, Vol. 128, No. 9, September 1,
2002, pp. 794-799.
Smith, G.M., 1999. Soil Insulation for Barrier Layer Protection in Landfill Covers, in Proceedings from
the Solid Waste Association of North America’s 4th Annual Landfill Symposium, Denver, Colorado, June
28-30, 1999.
U.S.D.O.E. 1989. Technical Approach Document, Rev. II, UMTRA-DOE/AL 050425.0002, Albuquerque,
New Mexico.
August 15, 2012
Interrogatory 011/1: R313-24-4; 10CFR40.Appendix A: Vegetation and Biointrusion Evaluation and Revegetation Plan Page 66 of 117
Yevjevich, V. 1982. Probability and Statistics in Hydrology, 3rd Edition. Water Resources Publications,
Littleton, Colorado.

August 15, 2012
Interrogatory 011/1: R313-24-4; 10CFR40.Appendix A: Vegetation and Biointrusion Evaluation and Revegetation Plan Page 67 of 117

INTERROGATORY WHITE MESA RECPLAN REV 5.0 R313-24-4; 10CFR40 APPENDIX A;
INT 11/1: VEGETATION AND BIOINTRUSION EVALUATION AND REVEGETATION PLAN
REGULATORY BASIS:
UAC R313-24-4 invokes the following requirement from 10CFR40, Appendix A, Criterion 1:-The general
goal or broad objective in siting and design decisions is permanent isolation of tailings and associated
contaminants by minimizing disturbance and dispersion by natural forces, and to do so without ongoing
maintenance. For practical reasons, specific siting decisions and design standards must involve finite
times (e.g., the longevity design standard in Criterion 6). The following site features which will contribute
to such a goal or objective must be considered in selecting among alternative tailings disposal sites or
judging the adequacy of existing tailings sites:
• Remoteness from populated areas;
• Hydrologic and other natural conditions as they contribute to continued immobilization and
isolation of contaminants from ground-water sources; and
• Potential for minimizing erosion, disturbance, and dispersion by natural forces over the long
term.
• The site selection process must be an optimization to the maximum extent reasonably achievable
in terms of these features.
In the selection of disposal sites, primary emphasis must be given to isolation of tailings or wastes, a
matter having long-term impacts, as opposed to consideration only of short-term convenience or benefits,
such as minimization of transportation or land acquisition costs. While isolation of tailings will be a
function of both site and engineering design, overriding consideration must be given to siting features
given the long-term nature of the tailings hazards.
Tailings should be disposed of in a manner that no active maintenance is required to preserve conditions
of the site.
UAC R313-24-4 invokes the following requirement from 10CFR40, Appendix A, Criterion 4: The following
site and design criteria must be adhered to whether tailings or wastes are disposed of above or below
grade:
(a) Upstream rainfall catchment areas must be minimized to decrease erosion potential and the size of the
floods which could erode or wash out sections of the tailings disposal area.
(b) Topographic features should provide good wind protection.
(c) Embankment and cover slopes must be relatively flat after final stabilization to minimize erosion
potential and to provide conservative factors of safety assuring long-term stabililty. The broad objective
should be to contour final slopes to grades which are as close as possible to those which would be
provided if tailings were disposed of below grade; this could, for example, lead to slopes of about 10
horizontal to 1 vertical (10h:1v) or less steep. In general, slopes should not be steeper than about 5h:1v.
Where steeper slopes are proposed, reasons why a slope less steep than 5h:1v would be impracticable
should be provided, and compensating factors and conditions which make such slopes acceptable should
be identified.
(d) A full self-sustaining vegetative cover must be established or rock cover employed to reduce wind and
water erosion to negligible levels.
Where a full vegetative cover is not likely to be self-sustaining due to climatic or other conditions, such as
in semi-arid and arid regions, rock cover must be employed on slopes of the impoundment system. The
August 15, 2012
Interrogatory 011/1: R313-24-4; 10CFR40.Appendix A: Vegetation and Biointrusion Evaluation and Revegetation Plan Page 68 of 117
Executive Secretary will consider relaxing this requirement for extremely gentle slopes such as those
which may exist on the top of the pile….
UAC R313-24-4 invokes the following requirement from 10CFR40, Appendix A, Criterion 6(1): In disposing
of waste byproduct material, licensees shall place an earthen cover (or approved alternative) over
tailings or wastes at the end of milling operations and shall close the waste disposal area in accordance
with a design which provides reasonable assurance of control of radiological hazards to (i) be effective
for 1,000 years, to the extent reasonably achievable, and, in any case, for at least 200 years, and (ii) limit
releases of radon-222 from uranium byproduct materials, and radon-220 from thorium byproduct
materials, to the atmosphere so as not to exceed an average release rate of 20 picocuries per square
meter per second (pCi/m2s) to the extent practicable throughout the effective design life determined
pursuant to (1)(i) of this Criterion. In computing required tailings cover thicknesses, moisture in soils in
excess of amounts found normally in similar soils in similar circumstances may not be considered. Direct
gamma exposure from the tailings or wastes should be reduced to background levels. The effects of any
thin synthetic layer may not be taken into account in determining the calculated radon exhalation level. If
non-soil materials are proposed as cover materials, it must be demonstrated that these materials will not
crack or degrade by differential settlement, weathering, or other mechanism, over long-term intervals.

INTERROGATORY STATEMENT:
Refer to Section 1.7.1, 3.3.1.0 and Appendices D and J of the Reclamation Plan Rev. 5.0: Please
provide the following:
1. Provide additional information (e.g., in the form of a survey and additional documentation of
existing animal and vegetation species that exist at the White Mesa site and nearby surrounding
region at this time to update the older information provided earlier.
Response 1 (August 15, 2012):
This response supersedes the response provided in the response document submitted
May 31, 2012.
A plant and animal survey was conducted at the White Mesa site and surrounding area
in June 2012 to update information provided in the Dames and Moore Environmental
Report (1978). Plant cover was estimated along point intercept transects in the Big
Sagebrush community type and through this survey the plant species that exist at the
site and surrounding area have been updated and included in a revision of Appendix D
to the Updated Tailings Cover Design Report (Appendix D of the Reclamation Plan,
Revision 5.0). The revised appendix is provided as Attachment G. A survey of
burrowing animals was also conducted with a focus on prairie dogs, badgers and
northern pocket gophers. This survey was conducted in both the Big Sagebrush and
Juniper communities either on site on in the surrounding area. Results for this survey
are also presented in Attachment G.

2. Update the list of plant and animal species to include plant and animal species (e.g. burrowing
animals) that could reasonably be expected to inhabit or colonize the White Mesa site within the
required performance period of the embankment (1,000 years, and in no case less than 200
years). In revising these lists, account for the types of vegetation and soils present in the vicinity
of the White Mesa site and proximity to the high quality northern pocket gopher and badger
habitat indicated in Utah distribution maps (Utah Division of Wildlife Resources).
Response 2 (August 15, 2012):
August 15, 2012
Interrogatory 011/1: R313-24-4; 10CFR40.Appendix A: Vegetation and Biointrusion Evaluation and Revegetation Plan Page 69 of 117
This response supersedes the response provided in the response document submitted
May 31, 2012.
A plant and animal survey was conducted at the White Mesa site and surrounding area
in June 2012. The information from these surveys was used to update the list of plant
and burrowing animal species that could reasonably be expected to inhabit or colonize
the White Mesa site within the required performance period of 200 to 1,000 years.
Results of these surveys are included in Attachment G.

3. Please report the estimated range of burrowing depths and burrow densities for animal species
found at the site and nearby surrounding region (once the updated study requested above is
complete), and for burrowing species that may reasonably be expected to inhabit the site within
the required performance period of the embankment (1,000 years, and in no case less than 200
years). Please comment on the root densities provided in Appendix D of the ICTM report.
Indicate whether the correct root density units were used in Table D-3 and Figure D-1. Also
verify that the correct values were used in the HYDRUS-2D infiltration model, since an
erroneously high value of root density could overestimate plant transpiration and underestimate
infiltration.
Response 3 (August 15, 2012):
This response supersedes the response provided in the response document submitted
May 31, 2012.
The estimated range of burrowing depths and burrow densities for animal species found
at the site and nearby surrounding region are reported in Attachment G. The June 2012
animal survey conducted in the area of the Mill site provided burrow densities and an
updated literature search was conducted on burrow depths for animal species that may
reasonably be expected to inhabit the site within the required performance period.
The root densities provided in Appendix D of the Revised Infiltration and Contaminant
Transport Modeling (ICTM) Report are incorrect because of a calculation error. Updated
and recalculated root biomass values are shown in Table 1 below. These corrected
values were used in the revised HYDRUS-1D infiltration model and results are provided
as part of a second response document to the Revised ICTM Report.
Table 1. Corrected root biomass (anticipated performance scenario and reduced
performance scenario) for the White Mesa Mill Site.
Depth (cm) Root Biomass (grams cm-3)
Anticipated Performance
Root Biomass (grams cm-3)
Reduced Performance
0-15 0.11 0.04
15-30 0.17 0.12
30-45 0.035 0.02
45-60 0.023 0.015
60-75 0.021 0.014†
75-90 0.019 0.0
90-107 0.011 0.0
†Maximum rooting depth under the reduced performance scenario would be 68 cm.
August 15, 2012
Interrogatory 011/1: R313-24-4; 10CFR40.Appendix A: Vegetation and Biointrusion Evaluation and Revegetation Plan Page 70 of 117

4. Rectify the mischaracterization of two plant species as presented in the two referenced documents
(Festuca ovina and common yarrow).
Response 4 (August 15, 2012):
This response supersedes the response provided in the response document submitted
May 31, 2012.
The seed mixture proposed for the ET cover at the White Mesa Mill site consists of
native and introduced species. The majority of species are native to Utah and two
species (Pubescent wheatgrass and sheep fescue) have been introduced to North
America. Sheep fescue was introduced from Europe in the 19th century, is commonly
found in Utah and highly used as a reclamation species. Pubescent wheatgrass was
introduced from Eurasia in 1907 and is also distributed in Utah from reclamation
seedings over the past 100 years.
Common yarrow (Achillea millefolium, var. occidentalis) is native to North America and is
found in Utah, according to the USDA Natural Resources Conservation Service’s Plant
Database (http://plants.usda.gov/java/). However, seed that is most available for
common yarrow (Achillea millefolium) is of an introduced origin and is commonly used in
reclamation plantings in Utah and throughout the western U.S. Seed of the native
variety, occidentalis, will be used in the seed mixture if seed is available. If the native
variety is not available, then the more common introduced variety will be used.
Galleta (Hilaria jamesii) has been added to the proposed seed mixture (Table 2), which
can be found in the Attachment G. Galleta is a native warm season grass that is very
common at the Mill site and makes an excellent addition to the proposed mixture.
Table 2. Species and seeding rates proposed for ET cover at the White Mesa Mill Site.
Scientific Name Common Name Variety Native/
Introduced
Seeding
Rate (lbs
PLS/acre)†
Grasses
Pascopyrum smithii Western wheatgrass Arriba Native 3.0
Pseudoroegneria spicata Bluebunch wheatgrass Goldar Native 3.0
Elymus trachycaulus Slender wheatgrass San Luis Native 2.0
Elymus lanceolatus Streambank wheatgrass Sodar Native 2.0
Elymus elymoides Squirreltail Toe Jam Native 2.0
Thinopyrum intermedium Pubescent wheatgrass Luna Introduced‡ 1.0
Achnatherum hymenoides Indian ricegrass Paloma Native 4.0
Poa secunda Sandberg bluegrass Canbar Native 0.5
Festuca ovina Sheep fescue Covar Introduced‡ 1.0
Bouteloua gracilis Blue grama Hachita Native 1.0
Hilaria jamesii Galleta Viva Native 2.0
Forbs
Achillea millefolium var.
occidentalis
Common yarrow No Variety Native 0.5
Artemisia ludoviciana White sage No Variety Native 0.5
Total 23.0
†Seeding rate is for broadcast seed and presented as pounds of pure live seed per acre (lbs PLS/acre).
August 15, 2012
Interrogatory 011/1: R313-24-4; 10CFR40.Appendix A: Vegetation and Biointrusion Evaluation and Revegetation Plan Page 71 of 117
‡Introduced refers to species that have been ‘introduced’ from another geographic region, typically outside of
North America. Also referred to as ‘exotic’ species.
5. Provide additional documentation to support conclusions made regarding the ability of the
proposed vegetation to establish at the cover percentages predicted. Also, provide additional
discussion regarding the potential sustainability of the cover design and characteristics as
proposed relative to changes that could occur due to the effects of natural succession and climate
change during the performance period (1,000 years, and in no case less than 200 years).
Response 5 (August 15, 2012):
This response supersedes the response provided in the response document submitted
May 31, 2012.
Additional documentation to support conclusions made regarding the ability of the
proposed vegetation to achieve predicted cover percentages is provided in the
Attachment G. Plant cover was measured in the Big Sagebrush community and results
support the predicted cover percentages for the plant community that will be established
on the ET cover system. In addition, a more in-depth discussion is presented in
Attachment G regarding potential sustainability of the cover design in relation to changes
that could occur during natural succession and under possible climate change scenarios.

6. Perform and report results of an additional infiltration sensitivity analysis to address the effects
of deep-rooted plants projected by the updated analysis described above. In particular, account
for any potentially deep-rooted species to assess the their effects of such deep-rooted species on
the characteristics of soil layers in the embankment cover system. Please provide a forecasted
percentage of potential species invasions in the ET cover system.
Response 6 (August 15, 2012):
This response supersedes the response provided in the response document submitted
May 31, 2012.
Revisions to the HYDRUS-1D infiltration model and results are provided as part of a
second response document to the Revised ICTM Report.
A discussion of the forecasted percentages of potential species invasions in the ET
cover system is provided in Attachment G.

BASIS FOR INTERROGATORY:
Burrowing animals have the potential to penetrate the cover system and disturb the waste tailings of a
cell. The burrowing animal could disturb the cover system resulting in “channels for movement of water,
vapors, roots, and other animals” EPA, Draft Technical Guidance for RCRA/CERCLA Final Covers,
April 2004 [EPA 2004]). The extent of damage caused by animal burrowing depends on the animals
burrowing depth ability. Mammals such as the badger and deer mouse have been reported at the site
and/or nearby the site and can burrow to depths of 150–230 cm [4.9 to 7.5 ft] (Anderson and Johns 1977,
Gano and States 1982, Cline, et al. 1982 and Lindzey 1976) and 50 cm [1.6 ft], respectively (Reynolds
and Laundre 1988 and Reynolds and Wakkinen 1987, and Smith, et al. 1997). Moisture content and
physical features of the soil can affect burrowing potential (Reichman and Smith 1990). Maximum
burrowing depths for animals at or near the site should be identified and appropriate measures taken to
August 15, 2012
Interrogatory 011/1: R313-24-4; 10CFR40.Appendix A: Vegetation and Biointrusion Evaluation and Revegetation Plan Page 72 of 117
protect the cover system, especially the radon barrier layer, from potential long-term damage/disruption
by burrowing animals.
Although Dames and Moore (1978) did not report pocket gophers and reported badgers only had
possibly a minor presence, the type of vegetation and soils present surrounding the facility is typical
habitat and Utah distribution maps (Utah Division of Wildlife Resources) show that the facility is within
or near the edge of high quality northern pocket gopher and badger habitat. Given the 34 years since the
Dames and Moore study, these species could occur now and will likely occur at some point during the
next 200 – 1000 years. Their potential presence needs to be acknowledged and considered in the design.
Other burrowing species that are not addressed and should be assessed include coyote and red fox.
The prairie dog species that could occur in this area is Gunnison’s prairie dog. The statement regarding
maximum burrowing depths for Gunnison’s prairie dog does not appear to represent current data, for
example Verdolin, Lewis, and Slobodchikoff (2008), which show studies with depths over one meter.
The statement that prairie dogs are unlikely to colonize the tailing cells is generally true, but does not
consider all potential events that could occur over an extended period of time, such as prolonged
drought, fire, or natural succession, that could affect plant cover.
The documents provide one reference (Waugh et al. 2008) for the ability to achieve 40% vegetation cover
for a long-term average and 30% under drought conditions. More support is needed that this cover can
be sustained long-term and under drought conditions. Regional data and/or data on the current plant
cover of the grassland vegetation at the White Mesa Mill should be present to support these cover
percentages. The ground cover measurements by Dames and Moore 1978 (provided on page 1-125 of
Reclamation Plan) are substantially less than 40%, but were collected during a drought and were likely
affected by past grazing.
The vegetation map and cover data presented in the Reclamation Plan Rev. 5.0 for the vegetation present
at the facility are 35 years old and do not represent current conditions. In addition, some of the cells are
identified as being partially reclaimed and no information is provided on reclamation methods or success
that would support the claim of being able to achieve 40% average cover. Current data should be
provided to support the estimates of potential cover expected to be achieved on the tailing cells. More
detailed information should be provided on deep-rooted species that currently occur in the study area and
that could become established on the tailing cells. There is little information provided on the composition
of local plant communities.
The plan does not adequately address the potential for natural succession over the 200-1000 year time
frame. The use of competitive grasses may exclude sagebrush for several decades, but may not work in
perpetuity. Shrub succession in seeded grasslands is a common phenomenon, and appears to be
occurring on portions of the seeded grasslands surrounding the White Mesa facility, based on current
aerial photographs. There should be a discussion of natural successional processes that could occur. Big
sagebrush is the regional climax dominant on deep soils such as the tailing cells will provide. The
eventual occurrence of some amount of big sagebrush should be identified as a possibility and the
analysis should include an evaluation of the compatibility of big sagebrush root systems with the cover
design, including depth of the soil and compacted layers. The highly compacted zone is likely to exclude
all or most roots, even for deep rooted species. References could be added to support this. There is a
lower potential for establishment of piñon and juniper.
According to Dames and Moore (1978), Table 2.8-2, community types identified within the site boundary
include Pinion-juniper Woodland, Big Sagebrush, and Controlled Big Sagebrush. Different published
references indicate that Big Sagebrush in the western U.S. can exhibit deeper rooting depths (e.g., see
Waugh, et al. 1994; Foxx, et al.1984; Klepper, et al. 1985, Reynolds 1990b). The statement in D.4.3 to
Appendix D to Appendix D of the Reclamation Plan Rev. 5.0, that “… species like sagebrush, piñon pine,
and Utah juniper have become dominant components of the regional flora primarily because of decades
of overgrazing that has removed more palatable grasses and forbs and allowed less palatable woody
August 15, 2012
Interrogatory 011/1: R313-24-4; 10CFR40.Appendix A: Vegetation and Biointrusion Evaluation and Revegetation Plan Page 73 of 117
species to establish and expand their range…” is an oversimplification and does not recognize that these
species are the climax species over a large portion of the Intermountain area. While overgrazing has
certainly reduced the abundance of perennial grasses and has led to shrub/tree invasion in some areas,
there is no evidence that these areas were primarily grassland prior to European settlement.
Table D-3 lists root densities that were used in the infiltration modeling. The values range from zero to
6.2 grams per cubic centimeter. The same values are shown graphically in Figure D-1 and again in
Appendix G, Figure G-1. It seems unreasonable to have such high root densities when the soil densities
are no greater than about 2 grams per cubic centimeter. Clarify whether the units in Table D-3 (g cm-3)
are correct. Alternative units might be milligrams (rather than grams) of roots per cubic centimeter or
centimeters of root length per cubic centimeter of soil.
It appears that all of the conclusions in the analysis of the effects of climate change are based on one 23-
year old study. Additional support is needed. In particular, the effects of extended droughts should be
addressed in more detail.
The documents mischaracterize the native status of two species. Festuca ovina is considered to be
introduced and not native throughout the entire lower 48 states (NRCS 2012). Common yarrow includes
both introduced and native sub-species. The seed mix should specify the yarrow subspecies that is native
to southern Utah. Several statements are made that the seed mix is comprised of natives, while it is
actually a mix of native and introduced species.
In the Reclamation Plan Rev. 5.0, no information is provided for the Tamarisk-Salix community identified
in Section 1.7.1. Based on current photography, they appear to be wetlands. It is unclear how they will
be affected by reclamation activities.

REFERENCES:
Anderson, D. C., and Johns, D.W. 1977. “Predation by Badger on Yellow-Bellied Marmot in Colorado,”
Southwestern Naturalist, Vol. 22, pp. 283–284.
Cline, J.F.. 1979. Biobarriers Used in Shallow-Burial Ground Stabilization. Technical Report.. Pacific
Northwest Laboratory PNL-2918. March 1, 1979.
Cline, J. F., K. A. Gano, and L. E. Rogers, 1980, “Loose Rock as Biobarriers in Shallow Land Burial,”
Health Physics, Vol. 39, pp. 494–504.
Cline, J. F., F.G. Burton, D. A. Cataldo, W. E. Skiens, and K. A. Gano. 1982. Long-Term Biobarriers to
Plant and Animal Intrusion of Uranium Tailings, DOE/UMT-0209, Pacific Northwest Laboratory,
Richland, Washington.
Denison Mines (USA) Corp., 2011. Reclamation Plan, White Mesa Mill, Blanding, Utah, Radioactive
Materials License No. UT1900479, Revision 5.0, September 2011.
EPA (U.S. Environmental Protection Agency). 2004. (Draft) Technical Guidance for RCRA/CERCLA
Final Covers. U.S EPA 540-R-04-007, OSWER 9283.1-26. April 2004, 421 pp. URL:
nepis.epa.gov/Exe/ZyPURL.cgi?Dockey=P10074PP.txt.
Foxx, T.S., G.D. Tierney, and J.M. Willimas, 1984. Rooting Depths of Plants Relative to Biological and
Environmental Factors, Los Alamos Report LA-10254-MS, November 1984.
Gano, K. A. and J. B. States, 1982, Habitat Requirements and Burrowing Depths of Rodents in Relation
to Shallow Waste Burial Sites, PNL-4140, Pacific Northwest Laboratory, Hanford, Washington.
August 15, 2012
Interrogatory 011/1: R313-24-4; 10CFR40.Appendix A: Vegetation and Biointrusion Evaluation and Revegetation Plan Page 74 of 117
Hakonson, T.E. 1986. Evaluation of Geologic Materials to Limit Biological Intrusion into Low-Level
Radioactive Waste Disposal Sites. LA-10286-MS. Los Alamos National Laboratory, Los Alamos, New
Mexico.
Lindzey, F. G. 1976. “Characteristics of the Natal Den of the Badger,” Northwest Science, Vol. 50, No. 3,
pp. 178–180.
Natural Resource Conservation Service (NRCS). 2012. Plants Database. http://plants.usda.gov/java/
Reichman, O.J., and Smith, S. C. 1990. “Burrows and Burrowing Behavior by Mammals,” pp. 197-244 in
H.H. Genoways, ed., Current Mammology. Plenum Press, New York and London. 1990.
Reynolds, T. D. and J. W. Laundre, 1988. “Vertical Distribution of Soil Removed by Four Species of
Burrowing Rodents in Disturbed and Undisturbed Soils,” Health Physics, Vol. 54, No. 4, pp. 445–450.
Reynolds, T. D. and W. L. Wakkinen, 1987. “Burrow Characteristics of Four Species of Rodents in
Undisturbed Soils in Southeastern Idaho,” American Midland Naturalist, Vol. 118, pp. 245–260.
Smith, E.D., Luxmoore, R.J., and Suter, G.W. 1997. “Natural Physical and Chemical Processes
Compromise the Long-Term Performance of Compacted Soil Caps,” in Barrier Technologies for
Environmental Management – Summary of a Workshop. National Research Council, National Academy
Press, Washington, DC., pp. D-61 to D-70.
Verdolin, Jennifer, Kara Lewis, and Constantine N. Slobodchikoff. 2008. Morphology of Burrow
Systems: A Comparison of Gunnison’s (Cynomy gunnisoni), White-tailed (C. leucurus), black-tailed (C.
ludovicianus), and Utah (C. parvidens) Prairie Dogs. The Southwestern Naturalist 53(2): 201-207.
Waugh, W. J., M. K. Kastens, L. R. L. Sheader, C. H. Benson, W. H. Albright, and P. S. Mushovic. 2008.
Monitoring the performance of an alternative landfill cover at the Monticello, Utah, Uranium Mill
Tailings Disposal Site. Proceedings of the Waste Management 2008 Symposium. Phoenix, AZ.
August 15, 2012
Interrogatory 012/1: R313-24-4; 10CFR40.Appendix A, Criterion 6(4): Report Radon Barrier Effectiveness Page 75 of 117
INTERROGATORY WHITEMESA RECPLAN REV 5.0 R313-24-4; 10CFR40 APPENDIX A,
CRITERION 6(4); INT 12/1: REPORT RADON BARRIER EFFECTIVENESS
REGULATORY BASIS:
UAC R313-24-4 invokes the following requirement from 10CFR40, Appendix A, Criterion 6(4): Within
ninety days of the completion of all testing and analysis relevant to the required verification in
paragraphs (2) and (3) of 10CFR40, Appendix A, Criterion 6, the uranium mill licensee shall report to the
Executive Secretary the results detailing the actions taken to verify that levels of release of radon-222 do
not exceed 20 pCi/m2s when averaged over the entire pile or impoundment. The licensee shall maintain
records until termination of the license documenting the source of input parameters including the results
of all measurements on which they are based, the calculations and/or analytical methods used to derive
values for input parameters, and the procedure used to determine compliance. These records shall be
kept in a form suitable for transfer to the custodial agency at the time of transfer of the site to DOE or a
State for long-term care if requested.
INTERROGATORY STATEMENT:
Refer to Reclamation Plan Rev. 5.0, Section 3 (Tailings Reclamation Plan) and Appendix D (Updated
Tailings Cover Design Report dated Sept 2011):
Please revise radon flux calculations using actual site-specific material properties data.
a. Clearly demonstrate that values of material parameters:
1) Are reasonably conservative
2) Are based on site material samples, measured values, assumptions, or other origins
3) Are based upon appropriate analytical methods and sufficient number of representative
samples for cover soils and tailings
4) Consider the variability and uncertainties in actual site-specific data.
5) Are consistent with anticipated construction specifications
6) Are based upon representative long-term site conditions.
Response a (August 15, 2012):
This response supersedes the response provided in the response document submitted
May 31, 2012.
A site investigation to further evaluate cover borrow materials was conducted on April
19, 2012. The results of laboratory testing on samples collected from the April 2012
investigation was used to develop updated cover material parameters for radon
emanation modeling. In addition, other model parameters were further evaluated as
necessary to address comments in this interrogatory. The results of the updated
analyses are provided in Attachment H as part of the revised Appendix C, Radon
Emanation Modeling, which will be included in the next version of the Updated Tailings
Cover Design Report (Appendix D of the Reclamation Plan).
August 15, 2012
Interrogatory 012/1: R313-24-4; 10CFR40.Appendix A, Criterion 6(4): Report Radon Barrier Effectiveness Page 76 of 117

b. Justify values of material parameters used in the radon flux calculations
Response b (May 31, 2012 and August 15, 2012):
See Response a.

c. Demonstrate that test methods and their precision, accuracy, and applicability are supported by
suitable standards and procedures.
Response c (May 31, 2012 and August 15, 2012):
See Response a.

d. Justify that values chosen for radon emanation and diffusion coefficients are consistent with long-
term moisture contents projected to exist within tailings and cover materials in the
impoundments.
Response d (August 15, 2012):
This response supersedes the response provided in the response document submitted
May 31, 2012.
The radon emanation coefficient parameter was revised for the updated radon analyses
presented in Attachment H to be 0.20 based on recommendations in NUREG-1620
(NRC, 2003) that states a “value of 0.20 may be estimated for tailings based on the
literature, if supported by limited site-specific measurements.”

A radon coefficient used in the model for the cover layers was revised to be 0.35 for the
updated radon analyses presented in Attachment H. A value of 0.35 is the conservative
default value used in the RADON model.

The radon diffusion coefficients can be calculated within the RADON model or input
directly using measured values (NRC, 2003). Although laboratory test data was
available, the tests were performed at porosities and water contents different than those
estimated to represent long-term conditions in the model. Therefore the values were
calculated within the RADON model. The revised radon modeling also used radon
diffusion coefficients that are calculated within the model.

Reference for Response d (August 15, 2012):
U.S. Nuclear Regulatory Commission (NRC), 2003. Standard Review Plan for the
Review of a Reclamation Plan for Mill Tailings Sites under Title II of the Uranium
Mill Tailings Radiation Control Act of 978. NUREG-1620, Revision 1, June.
e. Demonstrate that the quality assurance program used in obtaining parameter data is adequate
Response e (May 31, 2012 and August 15, 2012):
See Response a and Response d.
August 15, 2012
Interrogatory 012/1: R313-24-4; 10CFR40.Appendix A, Criterion 6(4): Report Radon Barrier Effectiveness Page 77 of 117

f. Revise the design density and porosity values of cover soils to comply with the usual compaction
of 95% of Standard Proctor (D 698). Alternatively, clearly justify the basis for the lower
compactions utilized in the radon flux calculations and their expected long-term stability.
Response f (August 15, 2012):
This response supersedes the response provided in the response document submitted
May 31, 2012.
The cover design consists of an evapotranspiration cover. The water storage layer will
be compacted to 85 percent of standard Proctor density and the lower random fill layer is
estimated to be compacted to 80 percent of standard Proctor density. Use of design
density and porosity values corresponding to 95 percent of standard Proctor density
would be inconsistent with the cover design.
g. Please revise the tailings density, porosity, and moisture values to reflect expected long-term
conditions in each of the disposal units. Alternatively, demonstrate the basis for the long-term
stability of the values used in the radon flux calculations.
Response g (August 15, 2012):
This response supersedes the response provided in the response document submitted
May 31, 2012.
The long-term tailings density was revised to be 90 pcf, based on laboratory tests (Chen
and Associates, 1987 and Western Colorado Testing, 1999) and assuming the long-term
density of the tailings is at 85 percent of the average laboratory measured maximum dry
density. The porosity of the tailings was calculated using the dry density and the
average measured specific gravity of 2.75 based on laboratory tests (Chen and
Associates, 1987 and Western Colorado Testing, 1999).
The long-term moisture content value for the tailings was assumed to be 6 percent in the
analyses presented in Denison (2011). This is the same value that was used for the
revised radon analyses. This is a conservative assumption, per NRC Regulatory Guide
3.64 (NRC, 1989), which represents the lower bound for moisture in western soils and is
typically used as a default value for the long-term water content of tailings.

References for Response g (August 15, 2012):
Chen and Associates, Inc., 1987. Physical Soil Data, White Mesa Project, Blanding
Utah, Report prepared for Energy Fuels Nuclear, Inc.
U.S. Nuclear Regulatory Commission (NRC), 1989. Calculation of Radon Flux
Attenuation by Earthen Uranium Mill Tailings Covers, Regulatory Guide 3.64.
June.
Western Colorado Testing, Inc., 1999. Report of Soil Sample Testing of Tailings
Collected from Cell 2 and Cell 3, Prepared for International Uranium (USA)
Corporation. May 4.

August 15, 2012
Interrogatory 012/1: R313-24-4; 10CFR40.Appendix A, Criterion 6(4): Report Radon Barrier Effectiveness Page 78 of 117
h. Please utilize one of the two accepted methods for long-term moisture estimates (D 2325 or
Rawls correlation) with representative samples. Alternatively, justify the use of an acceptable
alternative method.
Response h (August 15, 2012):
This response supersedes the response provided in the response document submitted
May 31, 2012.
Laboratory results for the 15 bar water contents for select samples from the April 19,
2012 field investigation were used to estimate long-term water contents for the random
fill and erosion protection layers. This is discussed further in Attachment H.

i. Please resolve or justify the discrepancy between the 91.4 pcf “best correlation” between the
Rawls and in-situ moisture data (Appendix D page C-4) and the density range of 94 to 111 pcf
used in the radon flux calculations. Revise and report results of radon flux calculations, as
necessary to reflect the resulting changes.
Response i (August 15, 2012):
This response supersedes the response provided in the response document submitted
May 31, 2012.
See Response h. The radon analyses were updated using the revised estimates for
long-term water contents.

j. Please utilize a source term based on representative sampling and analysis of the sand, slime,
and mixed tailings to 12-ft depths in sufficient and representative locations of each tailings area
(e.g., Cells 2, 3, 4A, and 4B.). Alternatively, justify and use the average ore grade method
identified in Reg Guide 3.64 for the radon flux calculations.
Response j (August 15, 2012):
This response supersedes the response provided in the response document submitted
May 31, 2012.
The revised estimation of the radium-226 concentration activities used for the tailings is
provided in Attachment H.

k. Please justify the assumed value of zero for Ra-226 concentrations in cover soils by sampling and
measurement of background Ra-226 soil concentrations and comparison of their values with
corresponding representative measurements in the proposed cover soils. Alternatively, use
values of Ra-226 concentrations in radon flux calculations that are supported by cell-specific
measurements.
Response k (May 31, 2012 and August 15, 2012):
Denison has established background values for Ra-226 in surface soil in the White Mesa
Mill area. These background values are very low, due to the absence of uranium
mineralization in the mill area. The cover soils that have been stockpiled are derived
from the same geologic formations as the soils measured for background values.
August 15, 2012
Interrogatory 012/1: R313-24-4; 10CFR40.Appendix A, Criterion 6(4): Report Radon Barrier Effectiveness Page 79 of 117
Therefore a Ra-226 value for cover soils of zero is appropriate in the radon flux
modeling, as outlined in NRC Regulatory Guide 3.64.
Reference for Response k (May 31, 2012 and August 15, 2012):
U.S. Nuclear Regulatory Commission (NRC), 1989. Calculation of Radon Flux
Attenuation by Earthen Uranium Mill Tailings Covers, Regulatory Guide 3.64.
June.

l. Please utilize measured radon emanation coefficients that are representative of the sand, slime,
and mixed tailings in the various tailings cell areas; emanation coefficients averaged over
measurements for each tailings cell. Alternatively, use default values conservatively estimated
from site-specific measurements.
Response l (May 31, 2012 and August 15, 2012):
See Response d.

m. Please utilize measured or calculated radon diffusion coefficients in radon flux calculations that
represent the long-term properties of the tailings and cover soil materials.
Response m (May 31, 2012 and August 15, 2012):
See Response d.

n. Please provide written procedures for identifying and placing contaminated soils into the
disposal cell(s) and substantiating characterization data and site history.
Response n (August 15, 2012):
This response supersedes the response provided in the response document submitted
May 31, 2012.
Procedures for identifying and placing contaminated soils is provided in Attachment A
(Plans and Technical Specifications) of the Reclamation Plan. Additional information on
procedures for identifying contaminated soils is provided in the responses to
Interrogatory 20/1.

o. Provide a revised radon emanation model that incorporates lower values of initial bulk density
for the erosion protection layer in the model. The bulk density value selected needs to fall within
the range of bulk densities that is recommended (approximately 1.2 to 1.8 g/cm3, or about 75 to
112 pcf) in the section entitled "Soil Requirements for Sustainable Plant Growth" and listed in
Table D-5 in Appendix D to the Reclamation Plan as the recommended range required for
promoting sustainable plant growth.
Response o (August 15, 2012):
This response supersedes the response provided in the response document submitted
May 31, 2012.
August 15, 2012
Interrogatory 012/1: R313-24-4; 10CFR40.Appendix A, Criterion 6(4): Report Radon Barrier Effectiveness Page 80 of 117
See Response a. The density of the rock mulch erosion protection layer was revised to
be based on the additional laboratory testing of potential cover soils (see Attachment
B.2). The previous density of the rock mulch provided in Appendix D of the Reclamation
Plan should was incorrectly listed as 124.2 pcf. It should have been listed as 107 pcf
based on the historical laboratory testing results. The updated rock mulch density is 106
pcf. This value was used in the radon modeling.

BASIS FOR INTERROGATORY:
a. The material parameters used in the radon flux calculations are not shown to be reasonably
conservative, and in some cases appear to be non-conservative. For example, the tailings density
(1.19 g/cc) appears to correspond to only 71% of standard proctor (based on Appendix D Table
3.4-1). If tailings settle to a greater density upon cover placement, the required cover thickness is
likely to increase.
b. The material parameters used in the radon flux calculations appear to ignore the variabilities
and uncertainties in parameter values. For example, some random-fill moistures are estimated
from 15-bar capillary suction values and others from the Rawls correlation, yet no account is
given for their uncertainties, equivalence, or applicability in apparently combining them for the
constant value of 7.8% moisture assumed for the range of cover layers (~78% to 92% of Proctor
density based on Appendix D Table 3.4-1 values).
c. Supporting information was not found for the test methods, their precisions, accuracies, and
applicability for the radon flux calculations.
d. Information was not found to identify the numerical origin of most parameter values used in the
radon flux calculations, their basis in site samples, measurements, or assumptions.
e. Information was not found to link the radon emanation and diffusion coefficients used in the
radon flux calculations to estimated long-term moisture contents at the site.
f. Information was not found to demonstrate that sufficient and representative samples were tested
to adequately determine material property values. For example, the tailings radium and
emanation values appear to be based on a single sample, whose identity, origin, or composition
is not identified (sand, slime, mixture? [Attachment A.1.5]). Approximately half of all “random
fill” to be used as cover soil appears to have never been sampled or characterized (Appendix D
Table 2-1).
g. Information was not found about quality assurance applicable to the parameter data used in the
radon flux calculations.
h. The consistency of material parameter values with anticipated construction specifications and
representation of long-term site conditions is not demonstrated. For example, the material
compactions of 71% for tailings, 82% for the first random fill layer, and 71% for the upper
random fill layer may increase with time due to natural settlement under the cover weight and
future land usage.
August 15, 2012
Interrogatory 012/1: R313-24-4; 10CFR40.Appendix A, Criterion 6(4): Report Radon Barrier Effectiveness Page 81 of 117
i. The target compaction values for two of the cover soil layers are less than the guideline
compaction values.
j. The tailings density, porosity, and moisture value appear un-sustainable for long-term support of
the overlying cover mass.
k. The deep in-situ moisture data referred to by NUREG-1620 Sec 5.1.3.1 (6) are intended for
comparison with D 2325 or Rawls values, not for averaging with them. The intent is to assure
that the measured D 2325 or Rawls values do not exceed the present field values. (i.e., the
smaller of the 15-bar or in-situ moistures should be used).
l. The chosen long-term moisture values should have a clear and traceable origin in representative
samples from the site.
m. The present Ra-226 concentration and radon emanation coefficient utilized for tailings in the
radon flux calculations is not justified by sampling and analysis data from representative sands,
slimes, and mixed tailings over the requisite depth interval and spatial distribution in the different
tailings areas nor by the ore-grade method described in Regulatory guide 3.64.
n. The Reclamation Plan does not demonstrate that the proposed cover soil materials are not
associated with ore formations or other radium-enriched materials or that their radioactivity is
essentially the same as surrounding soils as demonstrated by an appropriate procedure.
Procedures such as those in the MARSSIM manual are acceptable for this demonstration.
o. The single measured radon emanation coefficient of 0.19 lacks representation of sand, slime,
mixed, and cell-specific materials, and in particular, any potentially different values derived from
processing of alternate feed materials at the mill.
p. The radon diffusion coefficients used for tailings and cover soils in the radon flux calculations
lack traceability to representative, valid estimates of long-term moisture contents, densities, and
porosity values.
q. A written procedure was not found in the Reclamation Plan for identifying and placing in the
disposal cell all contaminated soils on and adjacent to the processing site , substantiated by
radiological characterization data and site history.
r. ….In the referenced section of Appendix D to the Reclamation Plan, it is stated that bulk densities
of emplaced cover materials will be specified in the cover design and will be controlled during
cover construction to be within the sustainability range shown in Table D-5. The radon
emanation modeling should therefore assume bulk density values for all cover layers that are
representative of the range of recommended bulk densities.
NOTE: The same comments as above also apply to Appendix D (Vegetation Evaluation for the
Evapotranspiration Cover) and Appendix H (Radon Emanation Modeling for the Evapotranspiration
Cover) of the Infiltration and Contaminant Transport Modeling (ICTM) Report.

REFERENCES:
NRC 2000. NUREG-1575 Rev.1, Multi-Agency Radiation Survey and Site Investigation Manual
(MARSSIM), August 2000.
August 15, 2012
Interrogatory 012/1: R313-24-4; 10CFR40.Appendix A, Criterion 6(4): Report Radon Barrier Effectiveness Page 82 of 117
NRC 2003. Standard Review Plan for the Review of a Reclamation Plan for Mill Tailings Sites under
Title II of the Uranium Mill Tailings Radiation Control Act of 1978. Washington DC, June 2003.
August 15, 2012
Interrogatory 013/1: R313-24-4; 10CFR40.Appendix A, Criterion 6(6): Concentrations of Radionuclides Other Than Radium in Soil Page 83 of 117
INTERROGATORY WHITEMESA RECPLAN REV 5.0 R313-24-4; 10CFR40, APPENDIX A,
CRITERION 6(6); INT 13/1: CONCENTRATIONS OF RADIONUCLIDES OTHER THAN
RADIUM IN SOIL
REGULATORY BASIS:
UAC R313-24-4 invokes the following requirement from 10CFR40, Appendix A, Criterion 6(6): The design
requirements in this criterion for longevity and control of radon releases apply to any portion of a
licensed and/or disposal site unless such portion contains a concentration of radium in land, averaged
over areas of 100 square meters, which, as a result of byproduct material, does not exceed the
background level by more than: (i) 5 picocuries per gram (pCi/g) of radium-226, or, in the case of
thorium byproduct material, radium-228, averaged over the first 15 centimeters (cm) below the surface,
and (ii) 15 pCi/g of radium-226, or, in the case of thorium byproduct material, radium-228, averaged
over 15-cm thick layers more than 15 cm below the surface.
Byproduct material containing concentrations of radionuclides other than radium in soil, and surface
activity on remaining structures, must not result in a total effective dose equivalent (TEDE) exceeding the
dose from cleanup of radium contaminated soil to the above standard (benchmark dose), and must be at
levels which are as low as is reasonably achievable. If more than one residual radionuclide is present in
the same 100-square-meter area, the sum of the ratios for each radionuclide of concentration present to
the concentration limit will not exceed "1" (unity). A calculation of the potential peak annual TEDE
within 1000 years to the average member of the critical group that would result from applying the radium
standard (not including radon) on the site must be submitted for approval. The use of decommissioning
plans with benchmark doses which exceed 100 mrem/yr, before application of ALARA, requires the
approval of the Executive Secretary after consideration of the recommendation of the staff of the
Executive Secretary. This requirement for dose criteria does not apply to sites that have decommissioning
plans for soil and structures approved before June 11, 1999.
Relevant NRC Guidance
Background Radiological Characteristics
RG 3.8, Section 2.10: Regional radiological data should be reported, including both natural
background radiation levels and results of measurements of concentrations of radioactive
materials occurring in important biota, in soil and rocks, in air, and in regional surface and local
ground waters. These data, whether determined during the applicant's preoperational
surveillance program or obtained from other sources, should be referenced.
INTERROGATORY STATEMENT:
1. Please propose appropriate soil background values (for different geological areas as needed) for
Ra-226, U-nat, Th-230, and/or Th-232, as appropriate, with supporting data.
Response 1 (August 15, 2012):
This response supersedes the response provided in the response document submitted
May 31, 2012.
The White Mesa Mill reports quarterly composite environmental air particulate data for
U-nat, Th-230, Ra-226 and Pb-210. The results of the environmental air sampling
presented in the Mill’s Semi Annual Effluent Reports show concentrations well below the
Mill’s ALARA goal of 25% of the regulatory standard for each radionuclide. Each of
these four radionuclides were considered in setting reference soil concentrations for
reclamation.
August 15, 2012
Interrogatory 013/1: R313-24-4; 10CFR40.Appendix A, Criterion 6(6): Concentrations of Radionuclides Other Than Radium in Soil Page 84 of 117

The reference soil concentrations for Ra-226 are set at 5 pCi/g and 15 pCi/g for the
surface 15 cm soil layer and the subsurface 15 cm soil layer, respectively (hereafter
referred to as “5/15”). The dose from Pb-210, which due to its short half-life is assumed
to be in equilibrium with the parent Ra-226, was assigned to the dose from Ra-226. (See
Attachment I for further discussion.) The site does not contain thorium byproduct
material, therefore Ra-228 and Th-232 are not applicable.
The soil concentration limits for radionuclides other than Ra-226 are derived from doses
calculated for Ra-226 at 5/15 using the same exposure scenarios as were used to
estimate the dose from Ra-226 at 5/15. This is referred to as the radium benchmark
dose (RBD). This approach was used to establish soil concentration limits for U-nat and
Th-230.
Based on available data, the preliminary estimate of background for Ra-226 is the
average concentration at the site background location (BHV-3) which is 0.93 pCi/g Ra-
226 as indicated in Section 6.6 of Attachment A. The 0.93 pCi/g Ra-226 background
concentration is close to nearby measurements from a background program with values
of 1.1 pCi/g Ra-226 near the airport entrance south of Blanding and 0.83 pCi/g Ra-226
southeast of Crescent Junction (Myrick et. al., 1981). The 32 Utah measurements
ranged from 0.53 to 1.9 pCi/g with an average of 1.3 pCi/g and a standard deviation of
0.74 pCi/g. In addition, Energy Fuels may use site-specific pre-mill background soil
concentrations if this information is available.
Preliminary estimates of background for U-nat and Th-230 are based on the Ra-226
concentration on the assumption of secular equilibrium for natural materials. Therefore,
the predicted U-nat background is 1.90 pCi/g (i.e., 2.051 times 0.93 pCi/g) with the Th-
230 background concentration set equal to 0.93 pCi/g.
These preliminary estimates of background concentrations are considered suitable for
the scoping survey; however, as recommended in the MARSSIM guidance, a site-
specific sampling program will be conducted prior to final status survey with the locations
selected with similar geology (surface soil) as the White Mesa areas, in order to
determine the background concentrations to be used for final decommissioning.
2. Please indicate whether elevated levels of uranium or thorium are expected to remain in the soil
after the Ra-226 criteria have been met, and if so, describe your use of the radium benchmark
dose approach (attt H of NUREG-1620) for developing decommissioning criteria for these
radionuclides.
Response 2 (August 15, 2012):
This response supersedes the response provided in the response document submitted
May 31, 2012.
Generally, elevation of U-nat and Th-230 concentrations relative to Ra-226 is
unexpected since the contaminated materials will either be ore (which are at or near
secular equilibrium) or tailings where U-nat is reduced relative to the other uranium
decay series radionuclides of interest. Possible exceptions are areas with raffinate
crystals which may have higher Th-230 concentrations compared to Ra-226
1 U-nat includes the activities from U-238, U-234 and U-235. The ratio of U-nat concentration to Ra-226
concentration under equilibrium conditions is 2.05 pCi/g U-nat per pCi/g
August 15, 2012
Interrogatory 013/1: R313-24-4; 10CFR40.Appendix A, Criterion 6(6): Concentrations of Radionuclides Other Than Radium in Soil Page 85 of 117
concentrations and areas of spilled yellowcake product near the Mill where U-nat maybe
elevated relative to Ra-226.
The RBD approach was applied as described in Attachment I. The RESRAD (Version
6.5) code was used to implement the RBD approach. The RESRAD code is an accepted
code by the NRC for application of the radium benchmark dose approach as described
in Guidance to the NRC Commission Staff on the Radium Benchmark Dose Approach, a
document included in NUREG 1569 as Appendix E (NRC 2003). In brief, radionuclides
at the reference soil concentration limits result in the same benchmark dose as the
allowable Ra-226 concentration.
The concentration limits for the radionuclides of interest were calculated and are
provided in Table 1 for the surface and subsurface layers. The scenario is for a rancher
with the doses determined using the RESRAD Version 6.5 model. The default RESRAD
dietary and inhalation data which apply for the adult are carefully selected from literature
and are already considered to represent conservative parameter values. Details on the
calculation of concentration limits are provided in Attachment I (the SENES letter report
on RBD).

Table 1 Incremental Concentration Limits Based on Radium Benchmark Dose
Incremental Concentration Limit (pCi/g)
Radionuclide Surface Layer Subsurface Layer
U-nat 545 2908
Th-230 46 142
Ra-226 5 a 15 a
Notes: a Allowable incremental Ra-226 concentration

Since there is more than one radionuclide, the criteria for unrestricted use is applied
using the unity rule such that the RBD is never exceeded (i.e., the sum of the ratios for
each radionuclide incremental concentration present to the concentration limit will not
exceed "1").
The concentration in the numerator is determined by subtracting the local background
from the total measured value following remediation. It is possible that the background
may vary between survey units due to variation in soil types.
The sum rules are:

For the surface soil:

August 15, 2012
Interrogatory 013/1: R313-24-4; 10CFR40.Appendix A, Criterion 6(6): Concentrations of Radionuclides Other Than Radium in Soil Page 86 of 117

For the subsurface soil:

Uranium ores arriving at the mill require very aggressive extraction in the mill in order to
recover uranium. This suggests that the uranium in ores processed at the Mill is in an
insoluble form. Similarly, residual uranium in solids discharged to the tailings was not
extracted through the mill process and can reasonably be assumed to be in an insoluble
form. Thus, it is reasonable to assume that any incremental (to background) uranium
remaining following remediation is most likely to be in non-soluble forms and hence,
chemical toxicity of uranium, which is dependent on exposure to soluble forms, is not
considered.
3. Please provide a description of the instruments and procedures that will be used for soil
background analyses, radium-gamma correlations, and verification data along with information
about the sensitivity of the procedures.
Response 3 (August 15, 2012):
This response supersedes the response provided in the response document submitted
May 31, 2012.
Gamma radiation surveys will be conducted either with the existing Ludlum-19
methodology that has been used for operational monitoring as well as previous
remediation at White Mesa, or with a GPS-integrated system using 2 inch by 2 inch
sodium iodide (NaI) detectors or the equivalent. Descriptions of the existing Ludlum-19
instrument and standard operating procedures are provided in the Mill’s Radiation
Protection Reclamation Manual. Procedures for the GPS-integrated survey will be
developed if that approach is to be used.
Statistical correlations will be developed between the sum rule and the gamma radiation
measurements. The sum rule will be determined from measurement data for
incremental concentrations at each sample location. The correlation between the
measurement sum rule and the gamma radiation measurement at the sample location
will produce a prediction equation. MARSSIM requires that the mean concentration in a
survey unit be demonstrably lower than criteria following remediation but does not
require all sampling units, in this case the 10 meter by 10 meter areas, to be lower than
the criteria. The precision goal for the relationship will be that the mean prediction
uncertainty for the survey unit will be +/- 0.2 when the predicted sum rule is equal to “1”.
The selected alpha error will be 0.05. The initial number of samples will be 15 and the
correlations will be assessed following the scoping survey and additional measurement
locations will be added, if necessary, to reach suitable precision. Although, final
verification requires that the mean is statistically below the criterion, the EFR goal will be
to remediate each 10 meter by 10 meter block, or sampling unit, so that the predicted
sum rule meets the criterion of “1”.
August 15, 2012
Interrogatory 013/1: R313-24-4; 10CFR40.Appendix A, Criterion 6(6): Concentrations of Radionuclides Other Than Radium in Soil Page 87 of 117
4. Please provide final verification (status survey) procedures to demonstrate compliance with the
soil and structure cleanup standards. The procedures should specify instruments, calibrations,
and testing, and the verification soil sampling density should take into consideration detection
limits of samples analyses, the extent of expected contamination, and limits to the gamma survey.
The gamma guideline value should be appropriately chosen, and the verification soil radium-
gamma correlation should be provided along with the number of verification grids that had
additional removal because of excessive Ra-226 values. The plan should provide for adequate
data collection beyond the excavation boundary. Surface activity measurements should
demonstrate acceptable compliance with surface dose standards for any structures to remain
onsite.
Response 4 (August 15, 2012):
This response supersedes the response provided in the response document submitted
May 31, 2012.
The final verification survey will be focused on ensuring that the excavation of
remediation areas has been established.
Gamma Radiation Surveys
Locations within the survey areas where excavation has been performed will have a
gamma radiation scan. Survey procedures with the Ludlum-19 methodology would
follow the existing procedures provided in the Mill’s Radiation Protection Reclamation
Manual.
With the GPS-integrated methodology, high density gamma radiation scanning surveys
can be done using the un-collimated Ludlum 44-10 detectors at a height of 18 inches
above the ground. Transects are planned to be 5 m apart to facilitate calculation of 10
meter by 10 meter averages, and this coverage will continue up to 20 meters outside the
excavation outline. These locations would correspond to a Class I classification in the
Multi-Agency Radiation Survey and Site Investigation Manual (MARSSIM NUREG-
1575). The remainder of the survey area outside the remediation area corresponds to
Class II in MARSSIM and will be surveyed at planned 10 meter transects. The gamma
radiation coverage goal will be that 95% of the 10 meter by 10 meter blocks have at
least 20 gamma radiation measurements for blocks in and immediately surrounding the
excavation areas with measurements in at least three of the four quadrants of the 10
meter by 10 meter block. The requirement for the remainder of the survey area, Class 2,
will be that 95% of the blocks have at least 10 gamma radiation measurements.
The Class 3 area will include the buffer areas outside the area of contamination, and this
area will be surveyed with planned transects of 50 meters. The requirement here is that
20% of the 10 meter by 10 meter blocks have at least 10 measurements.

Gamma Radiation Guideline Level
The gamma radiation data will be processed to establish the average gamma radiation
count rate over the 10 meter by 10 meter blocks. A correlation relationship will be
established between the gamma radiation level and the measured sum rule using
coincident gamma radiation and soil concentration measurements. The gamma
radiation guideline value will be the value such that the predicted mean is 0.8 for the
correlation relationship defined for the survey area and the DQO for 10 meter by 10
meter blocks has been attained for gamma radiation. Locations where the gamma
August 15, 2012
Interrogatory 013/1: R313-24-4; 10CFR40.Appendix A, Criterion 6(6): Concentrations of Radionuclides Other Than Radium in Soil Page 88 of 117
radiation guideline is exceeded will have additional excavation and updated gamma
radiation surveys before confirmatory sampling.

Selection of Verification Samples
Following completion of excavation, verification sampling will be carried out to meet two
objectives with the first being confirmation of the correlation equation and second, an
independent evaluation of the criteria based on soil samples alone. Locations for the
initial verification sampling will be established based on a combined selection of
sampling points using process history and a random sampling approach for each
investigation area. Following a final status gamma radiation survey, a minimum of 15
blocks in the survey unit will be measured to confirm the gamma radiation guideline
level. For these 15 samples, the five 10 meter by 10 meter blocks with the highest
average gamma radiation will be sampled along with another 10 sample blocks
randomly selected from the area.
The soil measurements from the 10 randomly selected locations will be assessed to
determine if the mean concentration in the survey unit is statistically below the sum rule
with an alpha error of 0.05 using the MARSSIM Sign test. (The Sign test is used
because the sum rule involves incremental above background concentrations.)
However, the statistical test could fail to show that the mean is below the criterion due to
the initial number of verification samples. In this case, the mean and variability of the 10
randomly selected measurements will be used to determine MARSSIM’s relative shift
with a target grey error equal to 0.8 of the sum rule. The alpha error will be set to 5%
and the beta error set to 10% to determine the required total number of samples. A
random sample will be determined for collection of the required number of additional
samples.

Revision of Correlation
The verification sample measurements will be compared to the correlation predictions to
determine if the correlation consistently over or under-predicts (i.e. is biased) the sum
rule. The correlation will be updated with the verification measurements if there is a
statistically significant departure, with a p-value of 0.05, over the range of interest (sum
rule from 0.5 to 1.0) evaluated using the paired difference between the predicted sum
rule using the correlation and the measured sum rule.

Reporting
For each survey area, the following will be reported:

1. Number of blocks remediated during remediation phase.
2. Number of blocks with subsequent remediation initiated by verification gamma
radiation sampling.
3. Gamma radiation coverage compliance (i.e. percentage of blocks meeting
number of measurement criteria).
4. Mean gamma radiation level averaged over the 10 meter by 10 meter blocks.
August 15, 2012
Interrogatory 013/1: R313-24-4; 10CFR40.Appendix A, Criterion 6(6): Concentrations of Radionuclides Other Than Radium in Soil Page 89 of 117
5. Mean and range of predicted sum rules based on gamma radiation survey.
6. Mean and range of measured sum rules based on verification sampling.

Only clean, uncontaminated buildings, such as office space may remain after
reclamation.

References for Responses (August 15, 2012)
Myrick, T.E., B.A. Berven and F.F. Haywood 1981. State Background Levels: Results of
Measurements Taken During 1975-1979, ORNL/TM-7343.
United States Nuclear Regulatory Commission (NRC) 2003. Standard Review Plan for
the Review of a Reclamation Plan for Mill Tailings Sites Under Title II of the
Uranium Mill Tailings Radiation Control Act of 1978 Final Report. NUREG-1620,
Rev.1. June.
United States Nuclear Regulatory Commission (US NRC), NUREG 1569, Appendix E,
Guidance to the U.S. Nuclear Regulatory Commission Staff on the Radium
Benchmark Dose Approach. 2003.
Yu, C., Zielen, A.J., Cheng, J-J, Le Poire, D.J., Gnanapragasam, E., Kamboj, S., Arnish,
J., Wallo III, A., Williams, W.A., and Peterson, H., 2001. User’s Manual for
RESRAD Version 6. ANL/EAD-4. July.

BASIS FOR INTERROGATORY:
1. Soil background values with supporting data were not found in the Reclamation Plan for Ra-226,
U-nat, Th-230, and/or Th-232.
2. No assessment of potentially elevated levels of uranium or thorium was found in the Reclamation
Plan for the post-Ra-226-reclamation site condition. This assessment should be included with the
requisite benchmark dose approach if elevated uranium or thorium may remain.
3. The Reclamation Plan does not describe the instruments and procedures that will be used for soil
background analyses, radium-gamma correlations, and verification data, nor information about
the sensitivity of the procedures. Helpful information may be found in the MARSSIM Manual.
4. The requisite procedures were not found for final verification surveys of the site to demonstrate
compliance with the soil and structure cleanup standards.

REFERENCES:
NRC 1982. U.S. Nuclear Regulatory Commission, “Regulatory Guide 3.8; Preparation of Environmental
Reports for Uranium Mills”, Washington DC, October 1982.
NRC 2003. Standard Review Plan for the Review of a Reclamation Plan for Mill Tailings Sites under
Title II of the Uranium Mill Tailings Radiation Control Act of 1978. Washington DC, June 2003.
August 15, 2012
Interrogatory 014/1: R313-24-4; 10CFR40.Appendix A: Cover Test Section and Test Pad Monitoring Programs Page 90 of 117
INTERROGATORY WHITE MESA RECPLAN REV 5.0 R313-24-4; 10CFR40 APPENDIX A;
INT 14/1: COVER TEST SECTION AND TEST PAD MONITORING PROGRAMS
REGULATORY BASIS:
UAC R313-24-4 invokes the following requirement from 10CFR40, Appendix A, Criterion 1:-The general
goal or broad objective in siting and design decisions is permanent isolation of tailings and
associated contaminants by minimizing disturbance and dispersion by natural forces, and to do so
without ongoing maintenance. For practical reasons, specific siting decisions and design
standards must involve finite times (e.g., the longevity design standard in Criterion 6). The
following site features which will contribute to such a goal or objective must be considered in
selecting among alternative tailings disposal sites or judging the adequacy of existing tailings
sites:
• Remoteness from populated areas;
• Hydrologic and other natural conditions as they contribute to continued immobilization and
isolation of contaminants from ground-water sources; and
• Potential for minimizing erosion, disturbance, and dispersion by natural forces over the long
term.
• The site selection process must be an optimization to the maximum extent reasonably achievable
in terms of these features.
In the selection of disposal sites, primary emphasis must be given to isolation of tailings or wastes, a
matter having long-term impacts, as opposed to consideration only of short-term convenience or benefits,
such as minimization of transportation or land acquisition costs. While isolation of tailings will be a
function of both site and engineering design, overriding consideration must be given to siting features
given the long-term nature of the tailings hazards.
Tailings should be disposed of in a manner that no active maintenance is required to preserve conditions
of the site.

UAC R313-24-4 invokes the following requirement from 10CFR40, Appendix A, Criterion 6(1): In
disposing of waste byproduct material, licensees shall place an earthen cover (or approved alternative)
over tailings or wastes at the end of milling operations and shall close the waste disposal area in
accordance with a design which provides reasonable assurance of control of radiological hazards to (i)
be effective for 1,000 years, to the extent reasonably achievable, and, in any case, for at least 200 years,
and (ii) limit releases of radon-222 from uranium byproduct materials, and radon-220 from thorium
byproduct materials, to the atmosphere so as not to exceed an average release rate of 20 picocuries per
square meter per second (pCi/m2s) to the extent practicable throughout the effective design life
determined pursuant to (1)(i) of this Criterion. In computing required tailings cover thicknesses, moisture
in soils in excess of amounts found normally in similar soils in similar circumstances may not be
considered. Direct gamma exposure from the tailings or wastes should be reduced to background levels.
The effects of any thin synthetic layer may not be taken into account in determining the calculated radon
exhalation level. If non-soil materials are proposed as cover materials, it must be demonstrated that these
materials will not crack or degrade by differential settlement, weathering, or other mechanism, over long-
term intervals.

August 15, 2012
Interrogatory 014/1: R313-24-4; 10CFR40.Appendix A: Cover Test Section and Test Pad Monitoring Programs Page 91 of 117

INTERROGATORY STATEMENT:
Refer to Section 8.0 of Attachment A (Technical Specifications and Attachment B (Construction
Quality Assurance/Quality Control Plan) to the Reclamation Plan and Section 5.0 of Appendix D
(Updated Tailings Cover Design Report) of the Reclamation Plan Rev. 5.0 (DUSA 2011a):

1. Please provide plans and specifications for constructing and performing monitoring and testing of
a cover system section representative of the proposed ET cover system for verifying the hydraulic
performance characteristics of the cover system. Demonstrate that the proposed test pad/plot will
be sufficient in size to eliminate or minimize lateral boundary effects. Describe objectives and
criteria for construction and testing of the test pad cover materials /layers. Include information in
the CQAQC Plan regarding procedures for sampling and testing of the cover system section
specifically pertinent to demonstrating the (short-term and long-term) performance of the ET cell
cover design. Address, as part of the testing program, testing of parameters specifically
recommended by Benson et al. 2011; Waugh et al. 2008; the National Research Council 2007;
Albright et al. 2007; others) including, but not necessarily limited to:
a. Monitoring of in-situ soil water tension and volumetric water content as a function of time (e.g.,
using heat dissipation probes and TDR [time domain reflectometry]);
b. Monitoring of in-situ flux rates as a function of time (e.g., through use of one or more pan
lysimeters as recommended by Benson et al. 2011 and Dwyer et al. 2007) on both north and
south-facing slopes as required);
c. Physical sampling and laboratory testing for index properties, including Plasticity Index and
saturated hydraulic conductivity, and other pertinent parameters including compaction
properties, organic matter and CaCO3 content, and measurement of soil edaphic properties
(properties that influence vegetation establishment and growth – e.g., see Waugh et al. 2008);
d. Other testing if needed for determining changes in water in storage and soil water characteristic
curves (SWCCs, e.g., according to ASTM D6836 [ASTM 2008]) and monitoring for potential
changes in SWCCs through time;
e. Conducting soil vegetation surveys (as recommended by Benson et al. 2011); and
f. Monitoring of relevant climatological parameters (precipitation and evaporation rates,
temperature, barometric pressure, snow amounts, wind speed and wind direction, etc...), including
continuous monitoring over several years necessary to understand how covers are influenced by
fluctuations in climate and other environmental factors (Waugh et al. 2008) such as an
extraordinarily wet year or consecutive wet years.

Response 1 (May 31, 2012 and August 15, 2012):
Denison proposes to install a performance monitoring section to evaluate the
performance of the final tailings cover system. The performance monitoring section will
be built into the final tailings cover system and will be monitored concurrently with the
operation of the final cover system. The proposed conceptual design and quality
assurance/quality control (QA/QC) of the performance monitoring section is briefly
described below. Detailed plans, specifications, and a QA/QC plan for construction and
August 15, 2012
Interrogatory 014/1: R313-24-4; 10CFR40.Appendix A: Cover Test Section and Test Pad Monitoring Programs Page 92 of 117
sampling will be prepared and submitted following approval of the proposed
performance monitoring by the Division.

Conceptual Design of the Performance Monitoring Section
Design Basis
The conceptual design of the performance monitoring section will be adopted from the
installation instructions for the test sections used in the Alternative Cover Assessment
Program (ACAP) (Benson et al., 1999) and incorporate the performance monitoring
recommendations provided in NUREG/CR-7028 (Benson et al., 2011) and site-specific
recommendations provided by Dr. Craig H. Benson (Craig H. Benson, personal
communication, May 8, 2012).

The performance monitoring area will be constructed as a large ACAP-style drainage
lysimeter that provides direct measurement of all components of the water balance (esp.
percolation), except evapotranspiration. In-situ soil water content and temperature
measurements of the cover soils will be taken within the performance monitoring area
and a weather station will be installed adjacent to the performance monitoring area.
Specifications for the performance monitoring area will be patterned after the ACAP test
section installation instructions (Benson et al., 1999) (see Attachment D of the May 31,
2012 response document) with the following exceptions:

• Soil water tension sensors will not be installed. Experience in ACAP showed that
data collected from the soil water tension sensors had little value for evaluating
cover performance. Additionally, soil water tension sensors can be challenging
to calibrate and operate. Soil water content sensors (water content
reflectometers) and temperature sensors will be installed. Although soil water
content and temperature are not direct measures of cover performance, data
from these sensors are useful information for interpreting cover performance
data, especially when performance metrics are not satisfied.

• The water content reflectometers will be installed in two nests rather than the
three nests used in ACAP. Experience at the ACAP test sites has shown little
spatial variability within the test sections, such that data from the three sets of
nested sensors was very similar (Craig H. Benson, personal communication, 8
May 2011). Two sensor nests will be used to provide a redundant set of water
content measurements, as recommended in NUREG/CR-7028 (Benson et al.,
2011).

• A sediment basin will not be installed for the surface run-off drainage.
Experience with the ACAP test sections showed that sediment control is not
needed (Craig H. Benson, personal communication, May 8, 2012).

Location

The performance monitoring section is proposed to be located in the northeast corner of
Cell 2 within the area that has a 0.5% slope. This location will have the flattest slope on
the cover system with the lowest potential run-off and represent the lower bound for
performance of the final cover system (Benson et al., 2011).

August 15, 2012
Interrogatory 014/1: R313-24-4; 10CFR40.Appendix A: Cover Test Section and Test Pad Monitoring Programs Page 93 of 117
Size
The size of the performance monitoring section will be 10 meters (perpendicular to the
slope gradient) by 20 meters (in the direction of the slope gradient), which is the same
size as an ACAP-style lysimeter. This section size is greater than 3 times the typical
spatial correlation length of the cover soils, thus providing a spatially averaged
percolation rate with little variability (Benson, 1991; Benson et al., 2011). A performance
monitoring area of this size also minimizes lateral boundary effects. This is the same
area that was used for the ACAP test cells and was found to be acceptable for all the
ACAP sites evaluated (Craig H. Benson, personal communication, May 8, 2012).

Components of Lysimeter

The lysimeter will include the following components:
• Geomembrane-lined (LLDPE) base and vertical side slopes.
• Geocomposite drainage layer draining percolation to a collection sump above the
LLDPE base.
• Geosynthetic root barrier layer above the radon attenuation and grading layer
(lower layer of cover system).
• Earthen surface run-off collection berm that collects surface run-off, diverts
surface run-on, and channels run-off to a single collection point.
• Separate PVC drainage pipes for percolation and surface run-off that drain to
separate measurement stations.

Instrumentation

Instrumentation will include water content reflectometers and temperature sensors to
measure water content and temperature of the cover soils in the lysimeter, tipping
buckets to measure percolation and surface runoff, and a weather station located
immediately outside of the lysimeter area. Two nests of water content reflectometers
and temperature sensors will be installed: one nest at the centerline of the upslope third
of the lysimeter and one nest at the centerline of the downslope third of the lysimeter.
Each nest will consist of six water content reflectometers and temperature sensors: two
placed in the radon attenuation and grading layer, two placed in the radon attenuation
layer, and two placed in the water storage layer.

Continuous monitoring of climatic data to understand how the cover is influenced by
fluctuations in climate and other environmental factors goes beyond performance
monitoring of the cover system. Using a dedicated weather station will reduce the effort
and inconsistencies that can be associated with integrating data from a site-wide
weather station and data collected from the lysimeter. The lysimeter weather station will
include a precipitation gauge, shielded temperature and humidity probe, pyranometer
(solar radiation sensor), and wind sentry (wind speed and direction).

All measurement devices will be wired to a single datalogger that can be accessed
remotely (e.g., via cellular). This will facilitate accurate and convenient integration of the
monitoring data and provide ready access for periodic quality control checks.

Conceptual Quality Assurance and Quality Control Plan for Performance Monitoring
Section

August 15, 2012
Interrogatory 014/1: R313-24-4; 10CFR40.Appendix A: Cover Test Section and Test Pad Monitoring Programs Page 94 of 117
The Construction Quality Assurance and Quality Control (CQA/CQC) plan for
reclamation will be revised to include provisions to test the construction of the
performance monitoring section and procedures for sampling and testing the cover soils
within the performance monitoring section. The QA/QC plan for the performance
monitoring section will include the following components:

• Preparing and compacting the foundation
• Testing the geomembrane integrity, including testing of welds and boots
• Leak testing the lysimeter, drainage pipes, and collection basins
• Programming, calibrating and testing instrumentation
• Testing of cover soil properties
• Vegetation survey

The QA/QC plan for testing of cover soil properties for the performance monitoring
section will include measurement of index properties, organic matter, saturated hydraulic
conductivity, and soil water content characteristic curves (SWCCs). These tests will be
conducted during construction to verify that the cover soils in the performance
monitoring section are representative of the as-built cover soils in other areas of the final
cover system. Denison is not proposing to test the soils throughout the operational
period to determine changes in properties with time. Monitoring the change in soil
properties with time, such as that done for the NUREG/CR-7028 (Benson et al., 2011) is
useful as a research endeavor to understand the evolution of the cover system, but is
un-necessary as a direct performance-based metric for the cover system. Performance
of the cover system will be evaluated by percolation from the cover to the percolation
rate predicted for the ground water contaminant transport assessment.

The QA/QC plan for vegetation surveys will be based on the recommendations in
NUREG/CR-7028 (Benson et al., 2011). This includes annual inspections of the
distribution of plant species, percent plant coverage, and leaf area index for the first five
years of operation. The vegetation surveys will be conducted for the final cover over the
tailings cells as well as for the performance monitoring section. Data from the
performance monitoring section and the final cover will be compared to ensure that the
vegetation on the monitoring section is representative of the vegetation on the final
cover.

References for Response 1 (May 31, 2012 and August 15, 2012):

Benson, C.H., 1991. Predicting Excursions beyond Regulatory Thresholds of Hydraulic
Conductivity Using Quality control Measurements, Proc. of the First Canadian
Conference on Environmental Geotechnics, Montreal, May 14-17, 447-454.
Benson, C.H., W.H. Albright, D.O. Fratta, J.M. Tinjum, E. Kucukkirca, S.H. Lee, J.
Scalia, P.D. Schlicht, and X. Wang, 2011. Engineered Covers for Waste
Containment: Changes in Engineering Properties and Implications for Long-Term
Performance Assessment, Volume 1 and 2, NUREG/CR-7028, Report Prepared
for the U.S. Nuclear Regulatory Commission, December.

2. Provide additional information and plans and specifications for constructing and testing a cover
system “test pad/test plot” prior to construction of the proposed ET cover system over the
August 15, 2012
Interrogatory 014/1: R313-24-4; 10CFR40.Appendix A: Cover Test Section and Test Pad Monitoring Programs Page 95 of 117
consolidated, dewatered tailings. Demonstrate that the proposed test pad/plot will be sufficient in
size to eliminate or minimize lateral boundary effects. Describe objectives and criteria for
construction and testing of the test pad cover materials /layers including but not limited to:
a. Acquisition of data of the types described in Item 1. above;
b. Determination of an acceptable zone (AZ) for soil textures in soils used for constructing the final
cover system (e.g., Williams et al. 2010);
c. Determination of most effective means of “bonding” individual soil cover soil layers (e.g., Dwyer
et al. 2007); and
d. Determination of appropriate lift thickness/placement and compaction equipment combinations
(e.g., Dwyer et al. 2007).

Response 2 (August 15, 2012):
This response supersedes the response provided in the response document submitted
May 31, 2012.
Denison is not proposing to construct a cover system test pad prior to construction of the
final cover system. Rather, Denison is planning to construct a performance monitoring
section to evaluate the performance of the final tailings cover system. Denison’s
recommendations for cover performance monitoring are outlined in Response 1. In
addition, Denison has completed extensive modeling of the cover system to demonstrate
that the cover will perform effectively for a variety of climatic and vegetative scenarios.
Denison has refined the modeling to incorporate the results of supplementary laboratory
testing conducted on the borrow soils for the cover. The refined modeling and additional
sensitivity analyses were conducted to address the Revised ICTM Interrogatories. The
results of the updated modeling are provided as part of the second response document
to the Revised ICTM Interrogatories.
Denison also believes that a cover system test pad is unnecessary given the wealth of
data collected at by ACAP at the Monticello Uranium Mill Tailings Disposal Facility near
Monticello, Utah. The Monticello site is approximately 35 kilometers northeast from the
White Mesa site. The earthen component of the Monticello cover, which is monitored by
ACAP, is analogous to the cover to be employed at White Mesa. Thus, the data from
Monticello provide an ideal analog for the performance expected at White Mesa.
The Monticello cover has been monitored continuously for nearly 12 years. During the
monitoring period from 12 August 2000 through 27 March 2012, the average annual
percolation rate at Monticello was 0.7 mm/yr and the average annual precipitation was
368 mm. The peak annual percolation rate was 3.8 mm/yr, and was received during the
second wettest year of the monitoring period (2005, 520 mm precipitation). During the
wettest year of the monitoring period (2010, 559 mm precipitation), the annual
percolation rate was 1.9 mm. This was the wettest year on record at Monticello (data
from Craig H. Benson, personal communication, 24 May 2012). These percolation rates
are within the range of rates and lower than maximum predicted rate for the infiltration
modeling for White Mesa.
The profile of the Monticello cover is shown in Figure 1. The profile of the White Mesa
cover was provided on Drawing TRC-8 of the Reclamation Plan and in Figure 1-1 of
Appendix D of the Reclamation Plan. A biointrusion layer embedded in the cover
(cobbles embedded in the fine-textured cover soil) and a sand drainage layer (at the
base of the cover) are the only additional features in the earthen component of the
August 15, 2012
Interrogatory 014/1: R313-24-4; 10CFR40.Appendix A: Cover Test Section and Test Pad Monitoring Programs Page 96 of 117
Monticello cover that are significantly different from the cover proposed for White Mesa.
The biointrusion layer reduces water storage capacity, which potentially may increase
percolation at Monticello relative to White Mesa. The sand drainage layer beneath the
cover at Monticello also acts as a capillary break, which enhances water storage and
may decrease percolation at Monticello relative to White Mesa. Thus, effects of the
biointrusion layer and sand drainage layer at Monticello are offsetting. Accordingly,
these differences between the covers at White Mesa and Monticello should result in only
marginal differences in hydrologic performance.

Figure 1. Monticello Evapotranspiration Cover Profile (from Waugh et. al, 2009)

Bonding Between Soil Lifts
Concern about lift bonding is based on prior studies on factors controlling the
effectiveness of compacted clay liners. Lifts that are carefully bonded are assumed to
transmit less water laterally between the lifts, and have lower likelihood of connectivity
between vertically oriented defects in adjacent lifts (Benson et al. 1994). This can be
particularly important for saturated conditions (i.e., for a liner), but is not relevant for
unsaturated conditions found in a water balance cover. Under unsaturated conditions,
larger pores and spaces such as interlift zones are not hydraulically active (Craig H.
Benson, personal communication, 24 May 2012).
August 15, 2012
Interrogatory 014/1: R313-24-4; 10CFR40.Appendix A: Cover Test Section and Test Pad Monitoring Programs Page 97 of 117
Field experience over the past two decades has also shown that complete bonding of
lifts is nearly impossible (Craig H. Benson, personal communication, 24 May 2012). In
nearly all cases, lift interfaces can be identified and lifts can be separated even if a high
level of effort is applied to promote lift bonding. The pragmatic approach is to recognize
that interlift zones exist and to use construction methods that render interlift zones as
tortuous as practical. This is most effectively done by leaving a rough upper surface on
the underlying lift prior to placement of the following lift (e.g., the impressions associated
with a compactor foot or the tracks on a dozer are effective in creating this rough
surface). Processes that promote a smooth surface, such as smooth drum compaction
and smooth blading of the surface, result in a much more transmissive interlift zone and
should be avoided (Craig H. Benson, personal communication, 24 May 2012).
At White Mesa, a rough surface will be maintained on the surface of all but the
uppermost lift to ensure that interlift zone is as non-transmissive as practical.

Lift Thickness and Compactors
Soil layers used for water storage in a water balance cover must have a pore space that
retains water and provide a favorable environment for roots. These constraints require
that the soil not be cover compacted, which is most effectively accomplished by using
relatively thick lifts of soil and machinery with lower ground pressure (e.g., dozer tracks
instead of a soil compactor). Lifts that are 18 inches thick and placed with a dozer can
normally be deployed with a relative compaction between 80-90% of standard Proctor
(i.e., a suitable density for root growth) (Albright et al. 2010).
Prior to construction at White Mesa, test strips will be constructed where the lift
thickness is varied and machinery is varied. Lift thicknesses and placement machinery
that promote uniform compaction of the soil without over compaction will be identified.

References for Response 2 (August 15, 2012):
Albright, W., Benson, C., and Waugh, W., 2010. Water Balance Covers for Waste
Containment: Principles and Practice, ASCE Press, Reston, VA, 158 p.
Benson, C. and Daniel, D., 1994. Minimum Thickness of Compacted Soil Liners: II-
Analysis and Case Histories, J. Geotech. Eng., 120(1), 153-172.
Utah Department of Environmental Quality, Division of Radiation Control (DRC), 2012.
Denison Mines (USA) Corp’s White Mesa Reclamation Plan, Rev. 5.0;
Interrogatories – Round 1. March.
Waugh, W.J., C.H. Benson, W.H. Albright, 2009. Sustainable Covers for Uranium Mill
Tailings, USA: Alternative Design, Performance, and Renovation, Proceedings
of the 12th International Conference on Environmental Remediation and
Radioactive Waste Management, ICEM2009-16369, October 11-15.

BASIS FOR INTERROGATORY:
The need for constructing and monitoring a cover test section representative of the proposed ET cover
system, with supporting basis and rationale for building and monitoring such a test cover section, was
August 15, 2012
Interrogatory 014/1: R313-24-4; 10CFR40.Appendix A: Cover Test Section and Test Pad Monitoring Programs Page 98 of 117
previously addressed in a Round 1A Interrogatory submitted to DUSA on Revision 4.0 of the Reclamation
Plan in October 2010. DUSA’s response (DUSA 2011b) to that interrogatory indicated the following:
“Denison is not proposing a test pad for demonstrating short- and long-term performance of the
alternative tailings cell cover system. Rather, Denison has completed extensive modeling of the cover
system for demonstrating that the cover will perform effectively for a variety of climatic and vegetative
scenarios. It may be possible to extend a portion of the cover system beyond the edge of the first tailings
cell such that the hydraulic conditions within the cover system could be evaluated through time (in a test
pad like setting) without causing deleterious effects to the cover above the tailings. This "test pad" would
be further evaluated after approval of the cover design”; and
“Denison is proposing monitoring in situ performance of the alternative tailings cell cover system to
include monitoring hydraulic conditions at nested intervals within the soil profile at three locations
within the first tailings cell that is reclaimed. The depth intervals that are evaluated would depend on the
final design specifications of the approved alternative cover system, but would likely represent data
collected from three depths. The first depth interval would be located immediately below the soil-gravel
admixture (0.6 feet), the second depth interval would be located near the midpoint of the maximum
rooting depth (1.5 feet), and the third depth interval would be located at or slightly below the maximum
rooting depth (3.8 feet) but above the proposed upper compacted layer;
“The pertinent hydraulic properties to be monitored would include soil water tension and volumetric
water content. Soil water tension would be measured with a heat dissipation probe, while volumetric
water content would be measured with a time domain reflectometry (TDR) probe. The use of these
monitoring methods is consistent with what was used to monitor conditions as part of the Alternative
Cover Assessment Program (ACAP). Changes in water content through time can be used to assess
changes in soil water storage through time. Measurements of volumetric water content and soil water
tension can be related to the soil water retention and hydraulic conductivity curves to estimate a water
flux rate and cover performance through time”…; and
“Climatological parameters are currently being measured at the site and include precipitation, wind
speed, and wind direction. In addition, air temperature and barometric pressures are measured monthly
for environmental air station calibrations. Based on this information in addition to supplemental climate
data from the nearest weather station (Blanding, Utah station 420738), the daily amount of
evapotranspiration can be computed.”
Although the response provided by DUSA to the Round 1A Interrogatory includes a proposal to monitor
the performance of the cover, additional details, including plans and construction specifications for
constructing a representative cover section, and detailed sampling and testing procedures and associated
quality assurance and quality control methods need to be provided that demonstrate that the test section
and monitoring/testing program: (1) is consistent with applicable current published guidance for such
programs: (2) is fully integrated with, and compatible with, the essential elements of the currently
proposed ET Cover design; (2) that data acquired from the monitoring/testing program will allow the
short-term and longer-term performance predictions made with regard to the proposed cover system to
be validated.
Applicable recent published guidance documents include NUREG/CR-7028 (Benson et al. 2011), a peer-
reviewed report published for the NRC in December 2011, which reports the findings from investigations
of several earthen and soil/geosynthetic cover systems to assess changes in properties of cover materials
in those cover systems 5 to 10 years following their construction. A key conclusion of the report is that
findings from these investigations demonstrate that changes in the engineering properties of cover soils
generally occur while in service (and that long-term engineering properties should be used as input to
models employed for long-term performance assessments). The report indicates that changes in hydraulic
properties occurred in all cover soils evaluated due to the formation of soil structure, regardless of
August 15, 2012
Interrogatory 014/1: R313-24-4; 10CFR40.Appendix A: Cover Test Section and Test Pad Monitoring Programs Page 99 of 117
climate, cover design, or service life. The report includes the following conclusions and
recommendations:
• Because cover systems change over time, they should be monitored to ensure that they
are functioning as intended. Monitoring using pan lysimeters combined with secondary
measurements collected for interpretive purposes (water content, temperature, vegetation
surveys, etc.) is recommended; and
• At a minimum, at least one pan lysimeter having a minimum dimension of 10 m should be
installed for performance monitoring. If only one lysimeter is installed, the location
should be selected to represent the most unfavorable condition at the site.

Additional relevant guidance documents include Waugh et al. 2008, Albright et al. 2007; Benson et al.
2007; and the National Research Council 2007, and Dwyer et al. 2007, which indicate that
characteristics of the proposed alternative cover will inevitably change in the long term in response to
climate, pedogenesis, and ecological succession.

Monitoring the proposed alternative cover system or monitoring of a test cover section simulating the
cover system components and geometry) to assess the long-term performance of the alternative cover is
needed to verify the characteristics and infiltration performance of the constructed cover system as well
as to gain confidence in understanding long-term changes that may occur in the physical/hydraulic
properties of the alternative cover system over time following its construction.
Additionally, a cover system test pad/test plot capable of assisting in confirming the performance of the
proposed alternative cover system should be constructed and monitored. The proposed alternative cover
design incorporates more loosely compacted soil layers. Dwyer et al. 2007, for example, describes
results of recent research and field investigations of arid climate closure covers conducted by Los Alamos
National Laboratory. As discussed in that report, lift thickness should be maximized for placement and
compaction of a soil cover. During cover placement, it is crucial that each lift be bonded to the previous
lift to cut down on the creation of interlift passageways (cracks) for the water to travel along as it passes
from an overlying lift to a lower one. Test pads prior to cover material placement may prove beneficial in
determining appropriate lift thickness/placement and compaction equipment combinations.
A full-scale cover system test pad/test plot can provide information that can lead to additional
performance criteria for the cover design process. Quantification of soil properties, soil placement
conditions and agronomic characteristics used in the test pad could, for example, help refine selection
criteria for selection of onsite soils for use in final cover construction, including, further definition of
soils that would result in a texture within a defined Acceptable Zone (AZ). The determination of the AZ
for soil texture may be based on the field test pad demonstration, hydraulic property testing, and
percolation modeling of the successful test plot soils.

REFERENCES:
Albright, W.H., Waugh, W.J., and Benson, C.H. 2007. “Alternative Covers: Enhanced Soil Water Storage
and Evapotranspiration in the Source Zone.” Enhancements to Natural Attenuation: Selected Case
Studies, Early, T.O. (ed), pp 9-17. Prepared for U.S. Dept. of Energy by Washington Savannah River
Company, WSRC-STI-2007-00250. URL:
http://www.dri.edu/images/stories/research/programs/acap/acap-publications/10.pdf.
August 15, 2012
Interrogatory 014/1: R313-24-4; 10CFR40.Appendix A: Cover Test Section and Test Pad Monitoring Programs Page 100 of 117
Benson, C.H., Sawangsuriya, A., Trzebiatowski, B., and Albright, W.H. 2007. “Postconstruction Changes
in the Hydraulic Properties of Water Balance Cover Soils”, Journal of Geotechnical and
Geoenvironmental Engineering, 133:4, pp. 349-359.
Benson, C.H. W.H. Albright, W.H., Fratta, D.O.,Tinjum, J.M., Kucukkirca, E., Lee, S.H., J. Scalia, J.,
Schlicht, P.D., and Wang, X. 2011. Engineered Covers for Waste Containment: Changes in Engineering
Properties and Implications for Long-Term Performance Assessment(in 4 volumes). NUREG/CR-7028,
Prepared for the U.S. Nuclear Regulatory Commission, Washington, D.C., December 2011.
Denison Mines (USA) Corp. 2011a. Reclamation Plan, White Mesa Mill, Blanding, Utah, Radioactive
Materials License No. UT1900479, Revision 5.0, September 2011.
Denison Mines (USA) Corp. 2011b. Responses to Supplemental Interrogatories – Round 1A for
Reclamation Plan, Revision 4.0, November 2009. December 28, 2011.
Dwyer, S.F., Rager, R.E., and Hopkins, J. 2007. Cover System Design Guidance and Requirements
Document. LA-UR-06-4715. EP2006-0667. Los Alamos National Laboratory. April 2007. URL:
http://www.lanl.gov/environment/cleanup/req_docs.shtml
National Research Council 2007. Assessment of the Performance of Engineered Waste Containment
Barriers. Board of Earth Sciences and Resources. The National Academies Press, Washington, D.C.,
2007, 134 pp.
Waugh, W. J., M. K. Kastens, L. R. L. Sheader, C. H. Benson, W. H. Albright, and P. S. Mushovic. 2008.
Monitoring the performance of an alternative landfill cover at the Monticello, Utah, Uranium Mill
Tailings Disposal Site. Proceedings of the Waste Management 2008 Symposium. Phoenix, AZ.
Williams, L.O., Zornberg, J.G., Dwyer, S.F., Hoyt, D.L., and Hargreaves, G.A. 2010. “Design Rationale
for Construction and Monitoring of Unsaturated Soil Covers at the Rocky Mountain Arsenal. 6th
International Congress on Environmental Geotechnics, New Delhi, India. URL:
http://www.ce.utexas.edu/prof/zornberg/pdfs/CP/Williams_Zornberg_Dwyer_Hoyt_Hargreaves_2010.pdf
August 15, 2012
Interrogatory 015/1: R313-24-4; 10CFR40.Appendix A, Criterion 9: Financial Surety Arrangements Page 101 of 117
INTERROGATORY WHITEMESA RECPLAN REV 5.0 R313-24-4; 10CFR40, APPENDIX A,
CRITERION 9; INT 15/1: FINANCIAL SURETY ARRANGEMENTS
REGULATORY BASIS:
UAC R313-24-4 invokes the following requirement from 10CFR40, Appendix A, Criterion 9: Financial
surety arrangements must be established by each mill operator prior to the commencement of operations
to assure that sufficient funds will be available to carry out the decontamination and decommissioning of
the mill and site and for the reclamation of any tailings or waste disposal areas. The amount of funds to
be ensured by such surety arrangements must be based on Executive Secretary-approved cost estimates in
a Executive Secretary-approved plan for (1) decontamination and decommissioning of mill buildings and
the milling site to levels which allow unrestricted use of these areas upon decommissioning, and (2) the
reclamation of tailings and/or waste areas in accordance with technical criteria delineated in Section I of
this Appendix. The licensee shall submit this plan in conjunction with an environmental report that
addresses the expected environmental impacts of the milling operation, decommissioning and tailings
reclamation, and evaluates alternatives for mitigating these impacts. The surety must also cover the
payment of the charge for long-term surveillance and control required by Criterion 10. In establishing
specific surety arrangements, the licensee's cost estimates must take into account total costs that would be
incurred if an independent contractor were hired to perform the decommissioning and reclamation work.
In order to avoid unnecessary duplication and expense, the Executive Secretary may accept financial
sureties that have been consolidated with financial or surety arrangements established to meet
requirements of other Federal or state agencies and/or local governing bodies for such decommissioning,
decontamination, reclamation, and long-term site surveillance and control, provided such arrangements
are considered adequate to satisfy these requirements and that the portion of the surety which covers the
decommissioning and reclamation of the mill, mill tailings site and associated areas, and the long-term
funding charge is clearly identified and committed for use in accomplishing these activities. The
licensee's surety mechanism will be reviewed annually by the Executive Secretary to assure, that
sufficient funds would be available for completion of the Reclamation Plan if the work had to be
performed by an independent contractor. The amount of surety liability should be adjusted to recognize
any increases or decreases resulting from inflation, changes in engineering plans, activities performed,
and any other conditions affecting costs. Regardless of whether reclamation is phased through the life of
the operation or takes place at the end of operations, an appropriate portion of surety liability must be
retained until final compliance with the Reclamation Plan is determined.
INTERROGATORY STATEMENT:
1. Justify the decrease in costs estimated for mill decommissioning and reclamation of Cells 1, 2,
and 3 from those estimated in the White Mesa Reclamation Plan, Rev. 4.0 dated November 2009.
Explain why several estimated levels of effort (e.g., total effort for Mill Yard Decontamination,
Ore Storage Pad Decontamination, Equipment Storage Area Cleanup and Cell 1 Construct
Channel) are smaller in 2011 than those estimated in 2009. Explain and rectify apparent
discrepancies between labor rates used in cost estimates and those presented in the exhibit in
Attachment C titled “Labor Costs”.
Response 1 (May 31, 2012 and August 15, 2012):
Comparison of the cost estimates for 2009 verses 2011 are meaningless at this time as
the estimates are for different cover systems, and the costs have been updated annually
to take into account variations in equipment rental rates, labor rates and changes in
material costs. In addition, the 2011 estimate utilized labor rates specific to the type and
size of equipment being operated, instead of an average labor rate for all machines.
Haul routes were also revised and updated to reflect current site conditions. Mill
August 15, 2012
Interrogatory 015/1: R313-24-4; 10CFR40.Appendix A, Criterion 9: Financial Surety Arrangements Page 102 of 117
decommissioning costs are also revised from year to year to take in to account the
expected volume of ore material and alternate feed material that may have to be hauled
to the tailings cells. These quantities can vary significantly from year to year.
Once the final cover design is conceptually approved, the cost estimate will be updated
utilizing revised material volumes, specific stockpile locations for each material type, and
updated equipment rental rates, labor rates and changes in material costs.

2. Identify analytes for which soil samples identified in the cost estimate for “Cleanup of
Windblown Contamination” will be analyzed. Justify (or revise with justification) the assumed
sample analysis cost of $50.
Response 2 (May 31, 2012 and August 15, 2012):
Verification soil samples will be analyzed for uranium, radium and thorium. Updated
analysis costs will be justified and utilized in the final cost estimate following conceptual
approval of the revised cover design and revised reclamation plan.

3. Revise and report estimated reclamation costs, incorporating responses to instructions listed
above.
Response 3 (May 31, 2012 and August 15, 2012):
See Response 1.

4. Estimate and report the costs for a third party to conduct decommissioning and impoundment
reclamation in the coming year rather than at the end of planned life.
Response 4 (May 31, 2012 and August 15, 2012):
Estimated reclamation and decommissioning costs are current costs assuming the
reclamation activity were to start immediately. The costs are for the facility as it exists at
the time of the estimate and not at the end of the planned life. The estimated costs
assume that the reclamation is conducted by an unaffiliated third party, overseen by the
State of Utah, Division of Radiation Control.

5. Please provide and justify estimates of costs associated with complying with the current Air
Quality Approval Order (DAQE-AN1205005-06, issue date July 20, 2006) and License Condition
11.4 and 11.5 during final reclamation, as stated in Section 1.5 of Reclamation Plan 5.0,
Attachment A, Technical Plans and Specifications.
Response 5 (May 31, 2012 and August 15, 2012):
Compliance with the Air Quality Approval Order and current License conditions are
incidental to the daily operation of the White Mesa Mill and will continue to be managed
by the onsite staff during reclamation activities. The management expense for this
activity is covered in the Miscellaneous section of the Reclamation Cost estimate.

August 15, 2012
Interrogatory 015/1: R313-24-4; 10CFR40.Appendix A, Criterion 9: Financial Surety Arrangements Page 103 of 117
6. Please state and justify the times projected to be necessary to dewater Cell 2 and Cell 3. Provide
and justify estimates of all costs associated with the apparently lengthy dewatering time for Cell 2
and Cell 3. Also see Interrogatory 7/01, item 8.
Response 6 (May 31, 2012 and August 15, 2012):
Cell 2 and Cell 3 dewatering costs are incidental to the daily operation of the White Mesa
Mill and will continue to be managed by the onsite staff during reclamation activities.
The management expense for this activity is covered in the Miscellaneous section of the
Reclamation Cost estimate. In addition, the current estimate includes the construction
and operation of a holding pond for solution from the dewatering of the tailings cells.
O&M costs for the dewatering of Cell 2 and Cell 3 will be re-evaluated once the final
cover design is conceptually approved. Consolidation of the tailings sands in Cell 2 and
Cell 3 is being monitored and, based on an analysis of the data, placement of the final
cover can take place prior to the termination of slimes drain dewatering.

BASIS FOR INTERROGATORY:
Comparing the cost estimate contained in Attachment C to Reclamation Plan Rev. 4.0 2009 with those
contained in Attachment C to Reclamation Plan Rev. 5.0 2011 reveals differences that should be
addressed. Contrary to expectations, the costs associated with mill decommissioning and reclamation of
most of the cells and some durations and levels of effort are smaller in 2011 than they were in 2009.
Some labor costs are not obviously supported by the data sources presented in the attachment.
Once Items 1 and 2 above have been addressed, the reclamation cost estimate should be revised and
resubmitted.
Without justification for an assumption to the contrary, the Division interprets the cost estimate as
applying to decommissioning and reclamation that occur at the projected end of facility life. If so, the
Licensee should also estimate the cost to decommission the mill area and reclaim all ponds under
conditions likely to exist within the next year. The financial assurance provided should ensure that funds
sufficient to cover costs of decommissioning and reclaiming within the next year are available to the
State.
Costs associated with complying with the current Air Quality Approval Order and License Condition 11.4
and 11.5 during final reclamation need to be included in the surety. Section 1.5 of Reclamation Plan 5.0,
Attachment A, Technical Plans and Specifications, states that reclamation will comply with State of Utah
Air Quality Approval Order (DAQE-AN1205005-06, issue date July 20, 2006).
The times required to dewater Cell 2 and 3 appear to will be lengthy, based on current dewatering rates.
Costs associated with this lengthy dewatering time for Cell 2 and 3 need to be included in the surety.
REFERENCES:
Denison Mines (USA) Corp. 2009. Reclamation Plan, White Mesa Mill, Blanding, Utah, Radioactive
Materials License No. UT1900479, Revision 4.0, November 2009.
Denison Mines (USA) Corp., 2011. Reclamation Plan, White Mesa Mill, Blanding, Utah, Radioactive
Materials License No. UT1900479, Revision 5.0, Appendix E, September 2011.

August 15, 2012
Interrogatory 016/1: R313-15-501: Radiation Protection Manual Page 104 of 117
INTERROGATORY WHITE MESA REC PLAN REV 5.0 R313-15-501; INT 16/1; RADIATION
PROTECTION MANUAL
REGULATORY BASIS:
UAC R313-15-501; Surveys and Monitoring General invokes the following requirement from 10CFR40,
Appendix A, Criterion 1: “(1) Each licensee or registrant shall make, or cause to be made, surveys that:(a)
Are necessary for the licensee or registrant to comply with Rule R313-15; and(b) Are necessary under the
circumstances to evaluate:(i) The magnitude and the extent of radiation levels; and(ii) Concentrations or
quantities of radioactive material; and(iii) The potential radiological hazards.
INTERROGATORY STATEMENT:
Refer to Appendix D, Radiation Protection Manual for Reclamation: Provide information on how these
largely operational radiation protection practices will change to support the changed needs of
decommissioning and reclamation. Describe how the Radiation Protection program will be evaluated
and revised to address the range of activities required to support decommissioning and reclamation
activities. The following are selected examples of topics (not exhaustive) that should be evaluated and
possibly revised to support decommissioning and reclamation.
• Section 1.3 Beta Gamma Surveys: Conduct beta gamma frisk surveys where appropriate during
decommissioning and reclamation.
• Section 1.4 Urinalysis Surveys: State the frequency of conducting urinalyses during
decommissioning and reclamation.
• Sections 2.1.2, 2.3.2, 2.4.2 Frequency/locations: State how the frequency and locations for all
monitoring methods will be modified to accommodate decommissioning and reclamation
activities.
Response (May 31, 2012 and August 15, 2012):
The Radiation Protection Manual for Reclamation has been updated to include additional
text regarding practices for decommissioning and reclamation and is included as
Attachment E to the May 31, 2012 response document.

BASIS FOR INTERROGATORY:
The Radiation Protection program provides information on regarding current operations but does not
any information on how these practices will change to support reclamation. While reclamation will
occur at a future date and the specific details may not be available at this time, it is important that the
Radiation Protection Program identify the approach that will be taken to address these needs.
REFERENCES:
Denison Mines (USA) Corp., 2011. Reclamation Plan, White Mesa Mill, Blanding, Utah, Radioactive
Materials License No. UT1900479, Revision 5.0, Appendix E, September 2011 :Attachment D Radiation
Protection Manual for Reclamation September 2011
August 15, 2012
Interrogatory 17/1: R313-15-1002: Release Surveys Page 105 of 117
INTERROGATORY WHITE MESA REC PLAN REV 5.0 R313-15-1002; INT 17/1; RELEASE
SURVEYS
REGULATORY BASIS:
UAC R313-15-1002; Method for Obtaining Approval of Proposed Disposal Procedures. A licensee or
registrant or applicant for a license or registration may apply to the Executive Secretary for approval of
proposed procedures, not otherwise authorized in these rules, to dispose of licensed or registered material
generated in the licensee's or registrant's operations. Each application shall include:(1) A description of the
waste containing licensed or registered material to be disposed of, including the physical and chemical
properties that have an impact on risk evaluation, and the proposed manner and conditions of waste
disposal; and(2) An analysis and evaluation of pertinent information on the nature of the environment;
and(3) The nature and location of other potentially affected facilities; and(4) Analyses and procedures to
ensure that doses are maintained ALARA and within the dose limits in Rule R313-15.
INTERROGATORY STATEMENT:
Refer to Attachment D, Section 2.6, Release Surveys: Revise to address the decontamination, release,
and disposal of equipment and buildings necessary to support decommissioning and reclamation.
Develop and present detailed release survey procedures and identify appropriate radiation survey
equipment that will be used. Develop and present additional decontamination procedures during
decommissioning and reclamation and include section on disposal of equipment that cannot be
decontaminated.
Response (May 31, 2012 and August 15, 2012):
Section 2.6 of the Radiation Protection Manual for Reclamation (Attachment D of the
Reclamation Plan, Revision 5.0) has been revised to include reference to a Release
Form outlining the procedures for release. The Release Form is included in the updated
Radiation Protection Manual for Reclamation (Attachment E to the May 31, 2012
response document).

BASIS FOR INTERROGATORY:
The decommissioning plan indicates equipment and structural material may be removed, decontaminated
and surveyed for unrestricted release. But the radiation protection plan does not include procedures, or
identify instruments that would be used on conduct these release surveys. NUREG-1575 Supplement 1
“Multi-agency Radiation Survey and Assessment of Materials and Equipment Manual (MARSAME)” may
be helpful in developing these procedures.
REFERENCES:
Denison Mines (USA) Corp., 2011. Reclamation Plan, White Mesa Mill, Blanding, Utah, Radioactive
Materials License No. UT1900479, Revision 5.0, Appendix E, September 2011 :Attachment D Radiation
Protection Manual for Reclamation September 2011
August 15, 2012
Interrogatory 18/1: R313-15-12: Inspection and Quality Assurance Page 106 of 117
INTERROGATORY WHITE MESA REC PLAN REV 5.0 R313-12; INT 18/1: INSPECTION
AND QUALITY ASSURANCE
REGULATORY BASIS:
UAC R313-12: an individual who has the knowledge and responsibility to apply appropriate radiation
protection rules and has been assigned such responsibility by the licensee or registrant.
INTERROGATORY STATEMENT:
Refer to Attachment A, Plans and Technical Specifications, Section 1.6, Inspection and Quality
Assurance: Revise the provided the “Radiation Protection Manual for Reclamation” cited in this section,
to define the responsibilities and duties of the Radiation Safety Officer.
Refer to Attachment A, Plans and Technical Specifications, Section 1.8b, Inspection and Quality
Assurance: Revise the wording to indicate that the DRC must review and approve all design
modifications to the Reclamation Plan.
Response (May 31, 2012 and August 15, 2012):
Section 1 of the Radiation Protection Manual for Reclamation (Attachment D of the
Reclamation Plan, Revision 5.0) has been revised to include the responsibilities of the
Radiation Safety Officer during reclamation (see Attachment E to the May 31, 2012
response document).
The wording in section 1.8b of the Technical Specifications will be revised to indicate the
DRC must review and approve all design modifications to the Reclamation Plan.

BASIS FOR INTERROGATORY:
Although Attachment A points to “Radiation Protection Manual for Reclamation” in identifying
responsibilities and duties of the Radiation Safety Officer, the provided manual does not identify these
responsibilities. The Radiation Safety Officers responsibilities during reclamation need to be identified,
as they will be different than what is required during operations.
DRC must be designated to approve of any design modifications to the Reclamation Plan.
Section 1.8b of Reclamation Plan 5.0, Attachment A, Technical Plans and Specifications,
describes “Possible submittal to, and review by, DRC for approval” of design modifications.
Attachment A needs to be revised to indicate that the DRC must review and approve all design
modifications to the Reclamation Plan.

REFERENCES:
Denison Mines (USA) Corp., 2011. Reclamation Plan, White Mesa Mill, Blanding, Utah, Radioactive
Materials License No. UT1900479, Revision 5.0, Appendix E, September 2011 :Attachment A, Plans and
Technical Specifications
Denison Mines (USA) Corp., 2011. Reclamation Plan, White Mesa Mill, Blanding, Utah, Radioactive
Materials License No. UT1900479, Revision 5.0, Appendix E, September 2011 :Attachment D, Radiation
Protection Manual for Reclamation September 2011
August 15, 2012
Interrogatory 19/1: R313-24; 10CFR40.42(J): Regulatory Guidance Page 107 of 117
INTERROGATORY WHITE MESA REC PLAN REV 5.0 R313-24; 10 CFR 40.42(J); INT 19/1:
REGULATORY GUIDANCE
REGULATORY BASIS:
UAC R313-24 incorporates 10 CFR 40.42(j) by reference: As the final step in decommissioning, the
licensee shall--(1) Certify the disposition of all licensed material, including accumulated wastes, by
submitting a completed NRC Form 314 or equivalent information; and (2) Conduct a radiation survey of
the premises where the licensed activities were carried out and submit a report of the results of this
survey, unless the licensee demonstrates in some other manner that the premises are suitable for release
in accordance with the criteria for decommissioning in 10 CFR part 20, subpart E or, for uranium milling
(uranium and thorium recovery) facilities, Criterion 6(6) of Appendix A to this part.
INTERROGATORY STATEMENT:
Refer to Attachment A, Plans and Specifications, Sections 6.4 Guidance: Please revise the
decommissioning plan to reference and incorporate current guidance, namely NUREG-1757
“Consolidated Decommissioning Guidance”; NUREG-1575 “Multi-Agency Radiation Survey and Site
Investigation Manual (MARSSIM)”; and NUREG-1575 Supplement 1 “Multi-agency Radiation Survey
and Assessment of Materials and Equipment Manual (MARSAME)”
Response (August 15, 2012):
This response supersedes the response provided in the response document submitted
May 31, 2012.
The decommissioning plan will be revised to incorporate reference to the applicable
guidance documents.

BASIS FOR INTERROGATORY:
This document references the use of NUREG-5849: “Manual for Conducting Radiological Surveys in
Support of License Termination” as the applicable guidance document. The current NRC guidance
documents for decommissioning are NUREG-1757 “Consolidated Decommissioning Guidance”;
NUREG-1575 “Multi-Agency Radiation Survey and Site Investigation Manual (MARSSIM)”; and
NUREG-1575 Supplement 1 “Multi-agency Radiation Survey and Assessment of Materials and
Equipment Manual (MARSAME)”.
REFERENCES:
Denison Mines (USA) Corp., 2011. Reclamation Plan, White Mesa Mill, Blanding, Utah, Radioactive
Materials License No. UT1900479, Revision 5.0, Appendix E, September 2011: Attachment A, Plans and
Technical Specifications
August 15, 2012
Interrogatory 20/1: R313-24; 10CFR40; Appendix A Criterion 6(6): Scoping, Characterization, and Final Surveys Page 108 of 117
INTERROGATORY WHITE MESA REC PLAN REV 5.0 R313-24,;10 CFR 40 APPENDIX A
CRITERION 6(6); INT 20/1: SCOPING, CHARACTERIZATION, AND FINAL SURVEYS
REGULATORY BASIS:
UAC R313-24 incorporates by reference 10 CFR 40 Appendix A Criterion 6(6): The design requirements
in this criterion for longevity and control of radon releases apply to any portion of a licensed and/or
disposal site unless such portion contains a concentration of radium in land, averaged over areas of 100
square meters, which, as a result of byproduct material, does not exceed the background level by more
than: (i) 5 picocuries per gram (pCi/g) of radium-226, or, in the case of thorium byproduct material,
radium-228, averaged over the first 15 centimeters (cm) below the surface, and (ii) 15 pCi/g of radium-
226, or, in the case of thorium byproduct material, radium-228, averaged over 15-cm thick layers more
than 15 cm below the surface.
INTERROGATORY STATEMENT:
1. Refer to Attachment A, Plans and Specifications, Sections 6.6 Scoping Surveys & Figure A-1:
Provide a figure identifying the areas and survey grid sizes. Clarify how use of the large grids and
the spacing shown in Figure A-1 will ensure compliance with the 100 square meter criteria. Explain
how samples will be collected from these larger grids.
Response 1 (August 15, 2012):
This response supersedes the response provided in the response document submitted
May 31, 2012.
Using process knowledge and site history, Energy Fuels Resources (EFR) will identify
areas of the site where the type of contamination is generally homogeneous (that is a
comparable contaminant signature) and the geology is similar. At this time, EFR
expects delineate two areas: tailings and an associated windblown area, and ore storage
area and an associated windblown area.
Each area within the restricted area has been divided into sub-areas of size 30 meter by
30 meters for the scoping gamma radiation survey. Contamination is probable in these
sub-areas and, following remediation, they would correspond to Class 1 or Class 2
MARSSIM areas. The gamma radiation survey plan shown in Figure A.1 has been
revised and is attached as the Revised Figure A.1. The 30 meter by 30 meter area will
cover each of the 10 m cells (blocks in the drawing) within each survey sub-area.
Effectively, a pattern of three transects per 30 meters provides coverage at the 10 meter
by 10 meter area, and this is suitable for the scoping survey. If any measurement within
the 30 meter by 30 meter area exceeds the action limit, a more detailed survey will be
conducted within the 10 meter by 10 meter block(s) which exceeded the action limit.
Areas where wind-blown contamination may be present will be divided into similar sub-
areas and the survey will continue outward from the restricted area until a buffer area of
gamma radiation radioactivity below the sum rule limit has been established. This will
bound the area for remediation and final status surveys.
Alternatively, gamma radiation scanning using the GPS-integrated system will be
conducted with a similar density as used in the Ludlum-19 methodology during the
August 15, 2012
Interrogatory 20/1: R313-24; 10CFR40; Appendix A Criterion 6(6): Scoping, Characterization, and Final Surveys Page 109 of 117
scoping surveys. As before, if any measurement exceeds the action limit, a more
detailed survey will be conducted locally.
The scanning gamma radiation levels from the scoping survey will be used to assist in
selecting locations for sample collection to develop the initial scoping level prediction
correlation. Locations where the sum rule is expected to be 0.5, 1 and 2 (corresponding
to incremental Ra-226 concentrations of 2.5, 5 and 10 pCi/g) will be selected, based on
historic knowledge and field observations, to accurately reflect the relationship near the
decision point. In addition, locations with higher concentrations, or areas where
substantial disequilibrium is anticipated, will be sampled.

2. Refer to Attachment A, Plans and Technical Specifications, Sections 6.6 Scoping Surveys: Provide
details (including information on instrument sensitivity) on the beta gamma radiation instruments
that will be used for the scoping surveys. Indicate the frequency of calibration checks, daily
operational checks, and other QA/QC requirements for the instruments. Also indicate whether these
same instruments (used during facility operations) will be used for subsequent characterization,
remediation, and final survey work.
Response 2 (August 15, 2012):
This response supersedes the response provided in the response document submitted
May 31, 2012.
Gamma radiation surveys will be conducted either with the existing Ludlum-19
methodology that has been used for previous remediation at White Mesa or with a GPS-
integrated system using 2 inch by 2 inch sodium iodide (NaI) detectors, or the
equivalent.
As indicated in the Mill’s Radiation Protection Reclamation Manual, each existing
instrument (Ludlum 19) used will be calibrated by an off-site 3rd party, every 6 months.
Daily function checks will be conducted and documented each morning before use. This
information will be housed in the Radiation Department. A function check is also
performed once the instruments return from calibration. This function check is
documented, and the daily checks are compared against this initial function check. If the
daily checks are off by more than ±10%, the instrument is considered no longer reliable
and must be sent in for calibration. All function checks are performed using a Cs-137
check source, similar to the 3rd party calibration laboratory.
The gamma radiation detectors to be used for the integrated-GPS methodology would
be 2 inch by 2 inch sodium iodide detectors (e.g. Ludlum 44-10 or equivalent) with a
ratemeter (e.g. Ludlum 2221 or equivalent) equipped with RS-232 export. The data is
exported to a GPS data logger for availability for mapping and survey interpretation.
These detectors are sensitive to environmental gamma radiation levels and typically
provide suitable precision for gamma radiation correlations below a level of 5 pCi/g.
Similar procedures to those currently used with the EFR Ludlum-19 methodology would
be developed, including for example, calibration and daily checks, if the GPS-integrated
methodology approach is selected
August 15, 2012
Interrogatory 20/1: R313-24; 10CFR40; Appendix A Criterion 6(6): Scoping, Characterization, and Final Surveys Page 110 of 117

3. Refer to Attachment A, Plans and Technical Specifications, Sections 6.6 Scoping Surveys: Explain
how areas contaminated with radium, thorium, and uranium will be identified and surveyed to ensure
they will not result in a dose that is greater than the radium standard alone.
Response 3 (August 15, 2012):
This response supersedes the response provided in the response document submitted
May 31, 2012.
A gamma radiation level that provides confidence that the sum rule is less than unity for
the survey unit will be established. This will be derived from the correlation between
gamma radiation and the sum rule from measurement data collected during the scoping
survey. The gamma radiation survey data will be analyzed to determine the extent of
contamination requiring remediation in each area based on this correlation.
4. Refer to Attachment A, Plans and Technical Specifications, Sections 6.6 Scoping Surveys: Identify
what types of samples (e.g., grab or composite samples) will be collected to support developing the
gamma correlation. Explain how locations for taking these samples will be selected. State how many
correlations will be developed and how they will differ from each other.

Response 4 (August 15, 2012):
This response supersedes the response provided in the response document submitted
May 31, 2012.
Soil samples collected during the scoping survey will be grab samples from locations
determined based on institutional knowledge and site history to ensure spatial coverage,
homogeneous areas relative to contamination type and geology and the range of
gamma radiation levels recorded in the scoping gamma radiation survey. At each
sampling location, a static gamma radiation measurement over a one minute duration
will be recorded with the same instrumentation and height above the soil as used in the
scanning surveys. Based on experience, the incremental gamma radiation
corresponding to 5.0 pCi/g Ra-226 is approximately 5,800 cpm for an un-collimated 2
inch NaI detector. Selection of sample locations will ensure that locations corresponding
to incremental concentrations of 2.5, 5 and 10 pCi/g are selected to optimize the
prediction uncertainty at the 5 pCi/g Ra-226 incremental concentration.
Correlations between the sum rule and gamma radiation will be developed with
potentially different relationships depending on the area. It is expected that the
relationships will generally not be dependent on the mixture of radionuclides in each
area. Most of the incremental gamma radiation is likely to be associated with Ra-226. U-
nat and Th-230 are weak gamma radiation emitters compared to Ra-226; however,
expectations are that these concentrations are equal to or less than the Ra-226
concentrations. For example, ore will have these radionuclides generally in equilibrium
and tailings will be depleted in uranium relative to Ra-226. However, there may be small
areas with elevated Th-230 due to specific process wastes (e.g. raffinate crystals).

August 15, 2012
Interrogatory 20/1: R313-24; 10CFR40; Appendix A Criterion 6(6): Scoping, Characterization, and Final Surveys Page 111 of 117
Differences in the relationship may be more dependent on variations in background due
potentially to different geology. The correlations will be evaluated for the differences that
depend on the area and the amount of precision (scatter of actual sum rule versus
predicted sum rule). The target (two sigma) absolute uncertainty for mean predictions
of the sum rule will be 0.2 at the decision point where the sum rule equals one; that is,
the 95% confidence intervals when the mean prediction equals “1” will be 0.80 to 1.2 for
the sum rule.

5. Refer to Attachment A, Plans and Technical Specifications, Sections 6.6 Scoping Surveys: Identify
the analytes including radioisotopes for which samples will be analyzed by chemical analysis and
identify the preferred analytical method.
Response 5 (August 15, 2012):
This response supersedes the response provided in the response document submitted
May 31, 2012.
Soil samples will be analyzed using methods with minimum detection limit (MDL) that is
no greater than 10% of the concentration limit developed from the radium benchmark
approach. The current methods used by the laboratories utilized by EFR are shown in
Table 1 and all meet the MDL objective noted above. The analytes and methodology
are given in the following Table 1.

Table 1 Analytical Methods and Method Detection Limits
Radionuclide Method RBD Benchmark MDL
Ra-226 E903.0 5 pCi/g 0.2 pCi/g
U-nat SW6020 Standard RL 545 pCi/g 0.01 pCi/g
Th-230 E908.0 46 pCi/g 0.2 pCi/g

6. Refer to Attachment A, Plans and Technical Specifications, Sections 6.6 Scoping Surveys: Provide
information on how other materials that may be left will be identified during scoping surveys.
Identify additional survey procedures for alpha beta and gamma surface surveys as appropriate.
Response 6 (August 15, 2012):
This response supersedes the response provided in the response document submitted
May 31, 2012.
August 15, 2012
Interrogatory 20/1: R313-24; 10CFR40; Appendix A Criterion 6(6): Scoping, Characterization, and Final Surveys Page 112 of 117

With respect to remediation of non-radiological hazardous constituents, NRC guidance
in NUREG-1620, Section 5.2.2 states:
“The decommissioning plan must address the non-radiological hazardous
constituents of the byproduct material according to 10 CFR 40 Appendix A
Criterion 6(7). For windblown tailings areas, meeting the surface Ra-226
standard should be adequate to control these constituents in soil. A tailings cell
cover that meets Appendix A criteria should control, minimize, or eliminate post
closure escape of non-radiological constituents into surface water and the
atmosphere. However any unusual or extenuating circumstances related to such
constituents should be discussed in the reclamation plan or decommissioning
plan in relation to protection of public health and the environment and should be
evaluated by the staff.”
EFR has reviewed the history of Mill operations and has identified the following two
incidents which may be considered to have generated “unusual or extenuating
circumstances” with respect to reclamation.

Ammonium Sulfate Tank Area
In response to a Stipulated Consent Agreement between EFR and the Director of the
Utah Division of Radiation Control (“DRC”), EFR performed Phase I of a Nitrate
Contamination Investigation described in a May 6, 2011 Investigation Plan approved by
DRC. The Phase I investigation identified soil contamination near the Mill’s ammonium
sulfate storage tanks, specifically ammonia as N, and nitrate plus nitrate as N, which
DRC attributed to spillage from storage and handling of ammonium sulfate process
reagent. Because the attributed source of the contamination is not associated with ores
or other sources of radiological contamination, EFR considers this area to represent an
unusual circumstance in which non-radiological contamination may not be captured by
excavation to the Ra-226 standard. EFR plans to remediate this contamination
consistent with agreements existing or currently under review by DRC, as described
below.
EFR entered a revised Stipulated Consent Agreement (“revised SCA”) with DRC on
September 30, 2011. Pursuant to the revised SCA, EFR submitted a revised Corrective
Action Plan (“CAP”) which, among other commitments, required that EFR:
• determine the physical extent of the soil contamination observed at the ammonium
sulfate, including an estimate of the volume of the contaminated soils down to but not
including bedrock, and an estimate of the surface area at or above the estimated
location of the contaminated soil volume;
• cover the Contaminated Surface Area with at least six inches of concrete, to the
extent not already covered by concrete or existing buildings, and
August 15, 2012
Interrogatory 20/1: R313-24; 10CFR40; Appendix A Criterion 6(6): Scoping, Characterization, and Final Surveys Page 113 of 117
• remove the Contaminated Soil Volume and dispose of the contaminated soils in the
Mill's tailings impoundments prior to site closeout.
The following process will be used to estimate the volume of contaminated soil to be
removed during reclamation. Once the total area to be covered by concrete has been
determined based on the borehole analyses, the area will be multiplied by the average
depth to bedrock, as determined from the logging of the boreholes.
Based on the geologic logging performed during the soil probe sampling in the Phase I
Investigation in June, 2011, borings number GP-25B and GP-26B in the vicinity of the
ammonium sulfate tanks indicated depth to bedrock of 19 feet and 16 feet, respectively.
These values will be included, along with depths determined during the additional
Geoprobe sampling to develop an average depth to bedrock. This average depth to
bedrock will be multiplied by the area of contamination.
The revised CAP and resulting Consent Order is currently undergoing public review and
comment. Following public comment and finalization of the CAP and Consent Order,
EFR will characterize the areal extent of contamination consistent with the schedule in
the revised CAP, and, at the time of Mill reclamation, excavate the contaminated soils
associated with the ammonium sulfate storage area consistent with the requirements of
the CAP and Consent Order.

Claricone Failure and Removal Action
The Mill experienced a spill from the failure of a partially below-grade clarifier (the
“Claricone”) on April 12, 2012. The spilled contents of the Claricone were expected to
consist of an estimated 28,000 gallons of in-process solutions containing approximately
190 lbs of natural uranium and approximately 3,370 lbs of sulfuric acid.
During April 2012 contaminated soil was removed and disposed in Cell 3 as follows:
a. All soils visibly wet, stained or discolored were excavated until uncontaminated dry
background soils remained.
b. The bottom and sides of the excavation were scanned by microR meter. When the
bottom or sides of the excavation indicated gamma levels greater than background
levels, the excavation was resumed, additional contaminated soil was removed,
and the bottom and sides of the excavation were re-scanned until all surfaces
resulted in gamma levels less than or equal to cleanup background. (Cleanup
background was defined as two times the average of four measured background
readings. This approach accounted for the contribution to background of gamma
radiation from other nearby process equipment such as the clarifier, thickener, and
CCD impounds.) When the bottom and sides of the excavation indicated gamma
levels of less than cleanup background as defined above, the excavation was
considered complete, and the area was prepared for backfill and re-grading.

August 15, 2012
Interrogatory 20/1: R313-24; 10CFR40; Appendix A Criterion 6(6): Scoping, Characterization, and Final Surveys Page 114 of 117
EFR considered that the excavation, as conducted based on residual gamma screening
was sufficient to ensure that all radiological and non-radiological constituents associated
with the spill had been addressed. However, DRC advised EFR in a letter dated August
8, 2012 that because confirmation sampling was not conducted subsequent to soil
removal, DRC required that EFR provide additional measures to ensure all
contamination has been removed. EFR has proposed to provide a conservative over-
estimate of contaminated soils to be excavated at the time of reclamation. EFR will
provide a report to DRC describing and justifying the estimated excavation volume.
Following approval of the report, and at the time of reclamation, EFR will excavate soil in
the former Claricone area consistent with the approved Excavation Proposal.

7. Refer to Attachment A, Plans and Technical Specifications, Sections 6.7 Characterization and
Remediation Control Surveys: Explain how many and how samples will be collected to ensure the
correlation developed for the scoping is consistent with the characterization and reclamation surveys.
Explain how the correlation will be modified to address gamma variations that may arise during
decommissioning and reclamation?
Response 7 (August 15, 2012):
This response supersedes the response provided in the response document submitted
May 31, 2012.
The correlations are anticipated to remain the same during the program provided that
the vertical gradient of incremental Ra-226 remains similar and that there are not
variations in background encountered. Soils after excavation may have higher or lower
concentrations than the established background due to differences in soil type. Soil
samples will be collected during the verification and these will ensure the relationship is
appropriate. These samples may initiate further excavation if the correlation is revised.

8. Refer to Attachment A, Plans and Technical Specifications, Sections 6.8 Final Survey, Figure A-2
and Attachment B Construction QA/QC Plan, Section 5.4.1: Please clarify the terminology used in
the two documents. Ensure that the activities described are consistent. Provide details on how the
10% of locations are selected for sampling. Demonstrate that collection of four samples as shown on
Figure A-2 is sufficiently representative of the entire 100-square-meter area. Explain whether
samples taken from the four sample locations identified in Figure A-2 will be analyzed separately or
will be composited.
Response 8 (August 15, 2012):
This response supersedes the response provided in the response document submitted
May 31, 2012.
Locations for final verification will be established based on a combined selection of
sampling points using process history and a random sampling approach for each
investigation area. Following a final status gamma radiation survey, a minimum of 15
blocks in the survey area will be measured to confirm the gamma radiation guideline
level. For these 15 samples, the five 10 meter by 10 meter blocks with the highest
average gamma radiation will be sampled along with another 10 sample blocks
randomly selected from the area.This will allow inspection of the highest gamma
August 15, 2012
Interrogatory 20/1: R313-24; 10CFR40; Appendix A Criterion 6(6): Scoping, Characterization, and Final Surveys Page 115 of 117
radiation blocks (which are more likely to have higher radionuclide concentrations) while
verifying the relationship and provide a measured soil sample average for the area.
Multiple sampling locations within a 10 meter by 10 meter block provides a more precise
measurement of the average sum rule for the block than would a single sample location.
The advantage of a composite sample is that the sample will more closely represent the
average over the block yet only one sample requires measurement. The advantage of
measurement of each sampling location (e.g. the four in Figure A.2 of Attachment A) is
that the laboratory uncertainty is averaged out amongst the samples. For example, if the
true concentrations were the same at each sampling point, the average of four locations
will average out the laboratory uncertainty more than the measurement of a single
composite. Based on achieving the desired MDLs for each radionuclide, a composite
sample from each 10 meter by 10 meter area is considered acceptable.
Four locations per 10 meter by 10 meter block has been selected as appropriate for the
site as contamination is generally expected to have smooth spatial variability (is not
“spotty”) particularly following remediation. Further, the soil sampling is largely
confirmatory of the more extensive gamma radiation measurements and correlation.

9. Refer to Attachment A, Plans and Technical Specifications, Sections 6.8 Final Survey, Figure A-2:
Explain how the areas where final survey soil sample results exceed the criteria will be addressed.
State the basis for determining whether additional removal will be required. A soil sample that
exceeds the criteria may also indicate a problem with the gamma correlation. Since the majority of
the area will be released based on the gamma correlation, explain how the gamma correlation will be
reviewed to ensure the use of the correlation in place of sampling is still valid.
Response 9 (August 15, 2012):
This response supersedes the response provided in the response document submitted
May 31, 2012.
Although not required by MARSSIM for the survey unit, further remediation on a
sampled block will be conducted if the unity rule determined with the soil sample
exceeds “1” for the soil layer. The remediation will follow the general approach used but
would involve a more extensive gamma radiation survey to define the area and to
ensure that the remediation is complete. A verification soil sample will be collected to
confirm that the sampled block meets the sum rule. The revised, if necessary, correlation
relationship will be implemented to determine if there are any 10 meter by 10 meter
blocks with a sum rule prediction that exceeds “1”. Any blocks exceeding the sum rule
will be remediated, for example by removing an additional lift and resurveying.

BASIS FOR INTERROGATORY:
1. The discussion in Section 6.6 does not clearly identify the survey grid sizes that will be used in the
described areas. Figure A-1 describes a serpentine gamma survey path, but this also indicates that a
total of 3 transects across the 30 meter grid will be made. With each transect representing only a 1-
meter-square area, a significant majority of the grid is not surveyed, and compliance with the 100-
August 15, 2012
Interrogatory 20/1: R313-24; 10CFR40; Appendix A Criterion 6(6): Scoping, Characterization, and Final Surveys Page 116 of 117
square-meter standard cannot be documented. It is unclear how the 30m x 30m grid relates to the
50m x50m grid.
2. Without more detailed information on the instrument that will be used it is impossible to determine if
the sensitivity is appropriate to verify compliance with the standard.
3. While the radium standard is appropriate for much of the site, as mentioned in the technical
specifications there are areas that are contaminated with a combination of nuclides, how will these
be identified, and what other survey procedures will be used to ensure the uranium and thorium are
addressed.
4. The general criteria for identifying appropriate sample locations should be developed to ensure the
resulting correlation is appropriate. Typically correlations are generated based on grab samples but
the discussion does not detail how the samples will be collected. Also it appears that multiple
correlations may be developed so proper communication regarding which correlation is appropriate
for each area is necessary to ensure compliance with the soil standard.
5. Specifics on the analyses to be performed are necessary to evaluate the proposed correlations. The
analytical methods need to be identified to ensure the appropriate analytical costs are included in the
cast estimate.
6. Additional definition and description is required to provide assurance that all contaminants will be
identified and properly processed during decommissioning and reclamation.
7. The gamma correlation that is developed for the scoping surveys may be valid, how will variations in
gamma rates associated with excavation depth and differences in material at depth be addresses.
8. The radiological survey descriptions in the documents are not consistent. The characterization survey
described in Attachment B is different than the characterization remediation survey described in
Attachment A. Without consistent terminology and survey descriptions it is impossible to evaluate the
survey descriptions. To ensure that collecting samples at only 10% of the remediated grids is
sufficient, the criteria used as the basis for the 10% must be provided. Typically, composite soil
samples for a 100 square meter area include between 5 and 11 aliquots to ensure the data is
representative of the entire area.
9. The plan should contain a commitment to perform a radium-gamma correlation on the verification
data, to track soil samples that fail the Ra-226 criteria, and to perform additional cleanup after a
verification soil sample exceeds the Ra-226 standard. Just cleaning the failed grid is not adequate
because the failed sample could indicate that the gamma value may not be conservative and that
some of the unsampled grids may also fail to meet the standard. For example, the plan could indicate
that neighboring grids would also be analyzed for Ra-226 or, if the number of failed grids is
excessive, the gamma guideline would be adjusted downward and areas further remediated, as
necessary.

REFERENCES:
Denison Mines (USA) Corp., 2011. Reclamation Plan, White Mesa Mill, Blanding, Utah, Radioactive
Materials License No. UT1900479, Revision 5.0, Appendix E, September 2011; Attachment A,
Plans and Technical Specifications
Denison Mines (USA) Corp., 2011. Reclamation Plan, White Mesa Mill, Blanding, Utah, Radioactive
Materials License No. UT1900479, Revision 5.0, Appendix E, September 2011: Attachment B,
Construction Quality Assurance/Quality Control Plan
August 15, 2012
Interrogatory 20/1: R313-24; 10CFR40; Appendix A Criterion 6(6): Scoping, Characterization, and Final Surveys Page 117 of 117
U.S. Geological Survey. 2012. Personal Communication (email) with Mr. Eric Martinez, Application
Developer. May 16.
2
,.....--~---------/
/'1
I
I
I
\
j
8
\
\,,........---4 ----5 -------.......6,
\
\
\
I
I,
I
9//1
-"------------........
e
.$Q)
E
a
C")
1
E
o......
-,",/...._"SCANNING PATH
:1
fEiale:UT
White Mesa Mill
loata:08-09-12 IOl1lftedBy:GM
Energy Fuels Inc.
Tocallon:
••Author.HR
Dale Bv County:SanJuan
REVISIONS Proleot:
..TYPICAL SCANNING PATH -SCOPING SURVEY
""""'::':=--1.---"::-1 RECLAMATION PLAN REV.3.2-FINAL
1-==--1......::·'_1 FIGURE A-1
• 30 m x 30 m grid showing the 10 m x 10m interior cells.
• If anyone of the scanned numbered cells meet or exceed the
action limit another S-shaped scan will be conducted inside the
numbered cell.
~..:qo
i
iii
~s~
g
~...JI::>s~~L...;.L..;;;;;,;;;""",l,__.L.._..;,;,;,;.__....l._,;;;,;;;.~~~~_~;;.........
ATTACHMENT A

SUPPORTING DOCUMENTATION FOR INTERROGATORY 01/1:

ASBESTOS INSPECTION REPORTS

ATTACHMENT A.1

ADMINISTRATION BUILDING
ASBESTOS INSPECTION REPORT

IIHHII
E NVIRONMENTAL

ASBESTOS INSPECTION REPORT

Administration Building
White Mesa Mill-Denison Mines Corp
6425 South Highway 191
Blanding, Utah1

August 1, 2012

Prepared for:
Ms. Jo Ann Tischler, Corporate Director of Compliance & Permitting
Denison Mines
1050 17th Street, Suite 950
Denver, Colorado 80265

Prepared by: Reviewed by:

Lono Folau
Asbestos Inspector #ASB-0537
Jon H. Self
Asbestos Program Manager

IHI Project 12U-A1081
640 EAST WILMINGTON AVE SALT LAKE CITY UT 84106 TELEPHONE: [phone] FAX: [phone] E-MAIL: [e-mail]

SALT LAKE CITY SAN FRANCISCO PHOENIX DENVER SEATTLE

TABLE OF CONTENTS

EXECUTIVE SUMMARY .............................................................................................................. I 
1.0 INTRODUCTION ..............................................................................................................1 
2.0  BUILDING DESCRIPTION ................................................................................................1 
3.0 INSPECTION PROCEDURES ............................................................................................2 
3.1 Asbestos-Containing Material (ACM) ...............................................................2 
3.2 Bulk Sampling ...................................................................................................2 
3.3 Bulk Sample Analysis ........................................................................................3 
4.0 INSPECTION RESULTS ....................................................................................................4 
4.1 Asbestos-Containing Materials ..........................................................................4 
4.2 Non-Asbestos-Containing Materials ..................................................................4 
4.3 Bulk Sample Analytical Results ........................................................................4 
4.4 Damage and Hazard Assessment .......................................................................5 
4.5 Materials Requiring Special Considerations ......................................................5 
4.6 Assumed Asbestos-Containing Materials ..........................................................5 
4.7 Inaccessible Areas ..............................................................................................5 
4.8 Materials Assumed >1% Asbestos (no NESHAP point count) .........................5 
5.0 RESPONSE ACTIONS ......................................................................................................6 
5.1 Applicable Rules and Regulations .....................................................................6 
5.2  Renovation and Demolition (EPA and OSHA) .................................................6 
6.0 COST ESTIMATES ..........................................................................................................7 

APPENDICES

Appendix A: Data Tables
Appendix B: Building Floor Plans
Appendix C: Photographs
Appendix D: Laboratory Results
Appendix E: Asbestos Regulatory Factors
Appendix F: Project Limitations

Denison Mines/Admin. Building-White Mesa Mill TOC - 1 IHI Environmental
Asbestos Inspection Project No. 12U-A1081

EXECUTIVE SUMMARY
On May 30, 2012, IHI Environmental conducted an asbestos inspection of the Administration
Building at the Denison Mines White Mesa Mill site in Blanding, Utah. Ms. Jo Ann
Tischler, Corporate Director of Compliance and Permitting for Denison Mines, requested this
inspection to identify asbestos-containing materials (ACM) that exist in the building.
ACM – IHI identified the following materials:
• Vinyl floor tile and mastic (7,960 square feet)
• Floor tile mastic (1,785 square feet)
Conclusions
Asbestos – IHI recommends that a Utah-certified asbestos abatement contractor remove and
properly dispose of all the ACM in this building that may be disturbed during remodel or
demolition activities.
Cost Estimates
IHI’s cost estimates for a Utah-certified asbestos abatement contractor to remove the ACMs
outlined above are approximately $35,650. The estimated cost does not include travel
expenses for an abatement contractor. These estimates do not include the costs for asbestos
abatement design and management consulting services.
The report that follows this Executive Summary should be read in its entirety because it
includes important information, such as material descriptions and locations, regulatory
requirements, and building-specific recommended response actions.
Denison Mines/Admin. Building-White Mesa Mill i IHI Environmental
Asbestos Inspection Project No. 12U-A1081
Executive Summary
Asbestos-containing Materials by Homogeneous Area
White Mesa Mill-Denison Mines Corp
Administration Building
Homogeneous
Area Number Material Description/Location Asbestos
Content Amount Cost
Estimate(1)
M004 5%
>1%
1,395 sq. ft.Chrysotile:
tile
Chrysotile:
masticHallways 100A, 100B, 100C, Rooms 101,
103, 116 and Closet 120
Floor Tile and Mastic on Cement - 12" x
12" Tan vinyl floor tile and black floor
mastic
$4,687
M005 5%
>1-6%
6,380 sq. ft.Chrysotile:
tile
Chrysotile:
masticThroughout floor of building
Floor Tile and Mastic on Cement - 12" x
12" Off-white vinyl floor tile with green
and black floor mastic
$21,437
M005A 6%1,440 sq. ft.Chrysotile
Throughout floor of building (under M005)
Floor Tile Mastic Under Non-ACM
Coverings - Black tar mastic
$4,838
M006
>1%
185 sq. ft.ND: tile
Chrysotile:
mastic
Women's Restroom and Men's Restroom
Floor Tile and Mastic on Cement - 12" x
12" Gray vinyl floor tile and black floor
mastic
$622
M007
>1%
1,600 sq. ft.ND: tile
Chrysotile:
masticChemical Laboratory 127 and Office 127F
Floor Tile-Exposed - 12" x 12" Light
tan vinyl floor tile
$4,032
Cost Estimates include asbestos removal costs only; abatement design, management fees and
replacement costs are not included. Please refer to Section 6.0 for more details.
Note 1:
Executive Summary Table Administration Building
White Mesa Mill-Denison Mines Corp
Page 1 of 1

ASBESTOS INSPECTION

Administration Building
White Mesa Mill-Denison Mines Corp
6425 South Highway 191
Blanding, Utah

1.0 INTRODUCTION
On May 30, 2012 IHI Environmental conducted an asbestos inspection of the Administration
Building located at 6425 South Highway 191 in Blanding, Utah. Ms. Jo Ann Tischler, of
Denison Mines Corporation, requested this inspection to identify asbestos-containing
materials (ACM) that exist in the facility.
2.0 BUILDING DESCRIPTION
• Building Identification
Building Name .............................Administration Building
Building Address ........................6425 South Highway 191, Blanding, Utah 84511
• Building Construction
Building Construction Date .........1978
Renovations..................................Not known
Building Type .............................Offices and laboratories
Building Total Sq. Ft....................9,090 square feet
Structural System ........................Concrete foundation with brick
Exterior Wall Construction .........Brick and metal
Floor Deck Construction .............Concrete
Roof Deck Construction .............Metal
Roof Construction .......................Metal
• Floors
Floors Above Grade .................... One (attic space-Room 121A)
Floors Below Grade .................... None
• Interior Finishes
Floors ...........................................Carpet, vinyl floor tile, ceramic tile and concrete
Walls ............................................ Wall system and brick
Denison Mines/Admin. Building-White Mesa Mill 1 IHI Environmental
Asbestos Inspection Project No. 12U-A1081

Ceilings ........................................ Suspended ceiling panels
Attic ............................................. None
Basement ..................................... None
• Building Mechanical
Heating Plant ............................... Not known
Main Heating Distribution: .......... Forced air
Cooling Plant ............................... Roof units
Main A/C Distribution ................. Forced air

3.0 INSPECTION PROCEDURES
3.1 Asbestos-Containing Material (ACM)
IHI visually inspected all accessible areas of the building to identify suspect ACM. To assess
the condition and determine friability of the suspect materials, IHI visually examined and
touched all accessible surfaces, structures, and mechanical systems within the building.
Suspect ACM was identified and assessed by homogeneous areas. A homogeneous area is
defined as a single material, uniform in texture and appearance, installed at one time, and
unlikely to consist of more than one type, or formulation, of material. In cases where joint
compound and/or tape has been applied to wallboard (gypsum board) and cannot be visually
distinguished from the wallboard, it is considered an integral part of the wallboard and in
effect becomes one material forming a wall or ceiling “system."
Each homogeneous area was given a unique material identification (ID) number. Each ID
number begins with a letter: "S" for surfacing materials, "T" for thermal system insulation, or
"M" for miscellaneous materials. This letter is followed by a three-digit number, assigned in
consecutive order. This number is used to identify that specific homogeneous area
throughout the inspection report.
3.2 Bulk Sampling
To determine the asbestos content of materials, IHI collected bulk samples from all
accessible homogeneous areas of suspect ACM and submitted the samples to an accredited
laboratory for analysis.
Denison Mines/Admin. Building-White Mesa Mill 2 IHI Environmental
Asbestos Inspection Project No. 12U-A1081

Denison Mines/Admin. Building-White Mesa Mill 3 IHI Environmental
Asbestos Inspection Project No. 12U-A1081
The number of samples collected from each homogeneous area generally followed the U. S.
Environmental Protection Agency (EPA) Asbestos Hazard Emergency Response Act
(AHERA) regulations (40 CFR §763.86). Friable surfacing materials were sampled using the
random sampling scheme given in the EPA publication 560/5-85-030a, titled "Asbestos in
Buildings: Simplified Sampling Scheme for Friable Surfacing Materials." Bulk sample IDs
collected during the inspection were entered on chain-of-custody forms for submittal to the
analytical laboratory.
3.3 Bulk Sample Analysis
Bulk samples were analyzed using polarized light microscopy (PLM) and visual estimation
according to the EPA Interim Method for the Determination of Asbestos in Bulk Insulation
Samples, EPA-600/M4-82-020. Samples were analyzed by Dixon Information Inc. in Salt
Lake City, Utah. Dixon Information is accredited under the National Institute of Standards
and Technology, National Voluntary Laboratory Accreditation Program (NIST-NVLAP) for
bulk asbestos sample analysis, and is also accredited by the American Industrial Hygiene
Association (AIHA).
EPA’s National Emissions Standards for Hazardous Air Pollutants (NESHAP) and AHERA
regulations define ACM as material containing greater than 1% asbestos by weight; materials
containing 1% or less asbestos are not considered regulated ACM by the EPA. Further, the
NESHAP regulations state that any sample found to contain less than 10% asbestos but
greater than “none detected," by the visual estimation method used during PLM analysis,
must be assumed to contain greater than 1% asbestos unless confirmed by NESHAP point
counting analysis.1
Despite EPA (and Utah Division of Air Quality) rules exempting building materials
containing 1% or less asbestos from stringent regulation, Occupational Safety and Health
Administration (OSHA) regulations outline specific precautionary work practices when
employees work with materials containing even trace amounts of asbestos.2

1 NESHAP point counting includes examining materials under a polarizing microscope using an eyepiece
reticule that superimposes a grid of points over the field of view. 400 points are examined. 2 OSHA regulations pertaining to asbestos in buildings include 29 CFR 1926.1101 and 29 CFR 1910.1001.
OSHA has also issued interpretive letters that provide clarification about how materials containing less than 1%
asbestos should be handled. (see www.osha.gov)

The laboratory reports can be found in Appendix D of this report.
4.0 INSPECTION RESULTS
4.1 Asbestos-Containing Materials
The Executive Summary and Table 1 in Appendix A list all homogeneous areas that contain
asbestos. Each material is described by type of material, friability and visual appearance.
Friability is defined in accordance with EPA’s NESHAP regulations.
• “Friable ACM” is any material containing more than 1% asbestos (as determined by
PLM) that, when dry, may be crumbled, pulverized, or reduced to powder by hand
pressure and also includes non-friable ACM that may become friable during building
demolition.
• “Non-friable ACM” is any material containing more than 1% asbestos (as determined
by PLM) that, when dry, cannot be crumbled, pulverized, or reduced to powder by
hand pressure.
• “Category I non-friable ACM” are asbestos-containing resilient floor coverings
(commonly known as vinyl asbestos tile (VAT)), asphalt roofing products, packings,
and gaskets.
• “Category II non-friable ACM” encompasses all other non-friable ACM.
• “Non-friable RACM” is used to denote thermal system insulation that is in good
condition but would become friable during renovation or demolition and therefore is
"regulated asbestos containing material" (RACM).
4.2 Non-Asbestos-Containing Materials
Homogeneous areas of suspect ACM are identified as non-ACM if material contains no
detectable asbestos. Table 2, located in Appendix A of this report, lists all homogeneous
areas that were found to be non-ACM.
4.3 Bulk Sample Analytical Results
Table 3, located in Appendix A of this report, lists all the bulk samples (chronologically by
sample number) collected from homogeneous areas of suspect ACM, and the laboratory
analytical results. Each sample was given a unique sample number. There may be more than
Denison Mines/Admin. Building-White Mesa Mill 4 IHI Environmental
Asbestos Inspection Project No. 12U-A1081

one sample number for the same homogeneous area of suspect ACM indicating multiple
samples were collected from that homogeneous material. The homogeneous areas of suspect
ACM are identified on this table by their material identification numbers. The sample
location listed on this table provides a brief, but specific, description of the location where
the sample was collected. This is different from the homogeneous area location provided on
Tables 1 and 2. Table 4 is the same as Table 3, except that the entries have been sorted by
homogeneous area number.
4.4 Damage and Hazard Assessment
Each homogeneous area of ACM was assessed for existing damage, accessibility, and
potential for future damage, this information is presented in Table 5, located in Appendix A
of this report. This table also lists the substrate beneath each homogeneous area of ACM.
Damage and hazard assessment categories are included in the tables in Appendix A.
4.5 Materials Requiring Special Considerations
None
4.6 Assumed Asbestos-Containing Materials
None
4.7 Inaccessible Areas
Suspect materials that were hidden or inaccessible may not have been characterized by this
inspection. Therefore, any material not identified in this report as having been tested should
be treated as suspect ACM until it has been sampled by a Utah-certified inspector and
analyzed by an accredited laboratory applying EPA methods.
In addition, some building structures may have been constructed after the application of
ACM, and therefore may have obscured these materials from visual examination during this
inspection. Typical scenarios include thermal system insulation inside hardened mechanical
chases, floor tile and mastic under walls, and sprayed-on texturing and fireproofing behind
structural supports or architectural features.
4.8 Materials Assumed >1% Asbestos (no NESHAP point count)
None
Denison Mines/Admin. Building-White Mesa Mill 5 IHI Environmental
Asbestos Inspection Project No. 12U-A1081

Denison Mines/Admin. Building-White Mesa Mill 6 IHI Environmental
Asbestos Inspection Project No. 12U-A1081
5.0 RESPONSE ACTIONS
5.1 Applicable Rules and Regulations
In Utah, EPA asbestos regulations are administered by the Utah Division of Air Quality
(DAQ).3 The Utah Occupational Safety and Health Administration (UOSH) has adopted the
Federal OSHA regulations.4 In addition, the Salt Lake Valley Health Department (SLVHD)
regulates demolition activities in Salt Lake County.5 The SLVHD regulations for pre-
demolition building inspections require an asbestos inspection, but also require building
owners to inspect the building for other hazardous materials such as universal wastes,
hazardous and toxic wastes, and lead-based paint. Like asbestos, these wastes, if present,
must be removed prior to building demolition.
Regulatory factors relevant to asbestos abatement decision-making are included in Appendix E.
5.2 Renovation and Demolition (EPA and OSHA)
A listing of ACM found during this inspection is presented in the Executive Summary at the
front of this report, and in Appendix A, Table 1.
NESHAP regulations require the removal of friable ACM and non-friable ACM that could
become friable during demolition or renovation activities. Therefore, we recommend that all
of the ACM in this building be removed and properly disposed of by a licensed asbestos
abatement contractor if total demolition of the facility is planned, or those materials that will
be impacted by renovation plans be removed prior to the commencement of renovation work.
Despite EPA (and Utah Division of Air Quality) rules exempting building materials
containing 1% or less asbestos from stringent regulation, Occupational Safety and Health
Administration (OSHA) regulations outline specific precautionary work practices when
employees work with materials containing even trace amounts of asbestos.6 Strict
3 R307-801. Asbestos, Utah Division of Air Quality Rules, Implementation of Toxic Substances Control Act
Title II, Asbestos Certification, Asbestos Training, notifications and Asbestos Work Practices for Renovations
and Demolitions (See www.airquality.utah.gov). 4 Asbestos, Tremolite, Anthophyllite, and Actinolite Standards, Chapter D (Construction), Section 58; and
Chapter Z (General Industry), Section 1001, Utah Occupational Safety and Health Rules and Regulations
(Administered by Utah Occupational Safety and Health Division) (See www.uosh.utah.gov). 5 Salt Lake City – County Health Department, Health Regulation #1 Section 12 (See www.slvhealth.org). 6 OSHA regulations pertaining to asbestos in buildings include 29 CFR 1926.1101 and 29 CFR 1910.1001.
OSHA has also issued interpretive letters that provide clarification about how materials containing less than 1%
asbestos should be handled. (see www.osha.gov)

Denison Mines/Admin. Building-White Mesa Mill 7 IHI Environmental
Asbestos Inspection Project No. 12U-A1081
compliance by building owners with the OSHA asbestos regulations may result in response
actions not required by the EPA and Utah DAQ for certain unregulated materials.
6.0 COST ESTIMATES
Details of the estimated removal costs by homogeneous area can be found in Table 6,
Appendix A, and in the Executive Summary table. These estimates are provided for
budgeting and planning only, and do not have a level of accuracy sufficient to be used as a
construction design cost estimate. The actual cost of asbestos removal is dependent on
factors such as the size of the job, the required time frame for removal, the time of year the
job is conducted, and economic factors. These estimates do not include replacement costs, or
the cost for asbestos abatement design and management consulting services.

Appendix A
Data Tables

Table 1
Asbestos-containing Materials by Homogeneous Area
White Mesa Mill-Denison Mines Corp
Administration Building
Homogeneous
Area Number Material Description/Location
Asbestos
Content AmountFriability
M004
12" x 12" Tan vinyl floor tile and black floor
mastic
Hallways 100A, 100B, 100C, Rooms 101,
103, 116 and Closet 120
5%
>1%
1,395Category 1
Non-friable
Floor Tile and Mastic on Cement sq. ft.Chrysotile: tile
Chrysotile:
mastic
M005
12" x 12" Off-white vinyl floor tile with green
and black floor mastic
Throughout floor of building
5%
>1-6%
6,380Category 1
Non-friable
Floor Tile and Mastic on Cement sq. ft.Chrysotile: tile
Chrysotile:
mastic
M005A
Black tar mastic
Throughout floor of building (under M005)
6%1,440Category 1
Non-friable
The yellow floor adhesive does not contain asbestos. The black floor mastic contained asbestos.
Floor Tile Mastic Under Non-ACM sq. ft.Chrysotile
M006
12" x 12" Gray vinyl floor tile and black floor
mastic
Women's Restroom and Men's Restroom
>1%
185Category 1
Non-friable
The gray vinyl floor tile did not contain asbestos. The black floor mastic underneath contained
asbestos.
Floor Tile and Mastic on Cement sq. ft.ND: tile
Chrysotile:
mastic
M007
12" x 12" Light tan vinyl floor tile
Chemical Laboratory 127 and Office 127F
>1%
1,600Category 1
Non-friable
The floor tile did not contain asbestos. However, the black floor mastic underneath contained asbestos.
Floor Tile-Exposed sq. ft.ND: tile
Chrysotile:
mastic
Asbestos Survey Report - Table 1 Administration BuildingPage 1 of 1
White Mesa Mill-Denison Mines Corp
Note: A homogeneous area of suspect material is considered an Asbestos-containing Material (ACM) if any one sample contains greater than 1% asbestos
Table 2
Homogeneous Areas That Do Not Contain Asbestos
White Mesa Mill-Denison Mines Corp
Administration Building
Material DescriptionHomogeneous
Area Number Material Description/Location Amount
M001
White joint compound, tan paper tape and
white gypsum plaster
Throughout interior walls of building
17,300 sq. ft.Wall System
M002
2' x 4' White coating ceiling panel (wormy
pattern)
Throughout ceiling
8,500 sq. ft.Ceiling Tile
M003
2' x 4' White coating ceiling panel (patches)
Restrooms 118, 122 and patches in Rooms
116, 117, 119 and 126
260 sq. ft.Ceiling Tile
M008
Off-white Transite cement panels
On the inside of cabinets (3' x2') under the
laboratory hoods in Rooms 126 and 127
8 unitsTransite Panel
M009
Brown adhesive
Throughout building
8,220 ln. ft.Cove Base Adhesive
M010
Gray sealant
Around ducts in Rooms 126 and 127.
20 ln. ft.Duct Sealant
Asbestos Survey Report - Table 2 Page 1 of 1 Administration Building
White Mesa Mill-Denison Mines Corp
Table 3
Bulk Sample Analytical Results by Sample Number
White Mesa Mill-Denison Mines Corp
Administration Building
Homogeneous
Area Number Material Sampled Analytical ResultsSample
Number Sample Location
AB-A1081-01 M001 Room 107-Safety Office NDWall System
AB-A1081-02 M001 Room 122-Men's Restroom NDWall System
AB-A1081-03 M001 Room 126-Metallurgical
Laboratory
NDWall System
AB-A1081-04 M002 Room 107-Safety Office NDCeiling Tile
AB-A1081-05 M002 Room 122-Men's Restroom NDCeiling Tile
AB-A1081-06 M002 Room 127-Chemical Laboratory NDCeiling Tile
AB-A1081-07 M003 Room 116-Coffee Area NDCeiling Tile
AB-A1081-08 M003 Room 119-Training Room NDCeiling Tile
AB-A1081-09 M003 Room 126-Metallurgical
Laboratory
NDCeiling Tile
AB-A1081-10 M004 Room 116-Coffee Area 5%
>1%
Chrysotile-tile
Chrysotile-
mastic
Floor Tile and Mastic
on Cement
AB-A1081-11 M004 Room 120-Custodial Closet 5%
>1%
Chrysotile-tile
Chrysotile-
mastic
Floor Tile and Mastic
on Cement
AB-A1081-12 M004 Room 100-Waiting Area 5%
>1%
Chrysotile-tile
Chrysotile-
mastic
Floor Tile and Mastic
on Cement
AB-A1081-13 M005 Room 111-Conference Room 5%Chrysotile-tileFloor Tile and Mastic
on Cement
Asbestos Survey Report - Table 3 Page 1 of 2 Administration Building
White Mesa Mill-Denison Mines Corp
Homogeneous
Area Number Material Sampled Analytical ResultsSample
Number Sample Location
AB-A1081-14 M005 Room 121-Bioassay Room 5%Chrysotile-tileFloor Tile and Mastic
on Cement
AB-A1081-15 M005A Room 121-Bioassay Room 6%ChrysotileFloor Tile Mastic
AB-A1081-16 M006 Room 118-Women's Restroom
>1%
ND-tile
Chrysotile-
mastic
Floor Tile and Mastic
on Cement
AB-A1081-17 M006 Room 122-Men's Restroom
>1%
ND-tile
Chrysotile-
mastic
Floor Tile and Mastic
on Cement
AB-A1081-18 M007 Room 127F-Chief Chemist
Office
ND-tileFloor Tile-Exposed
AB-A1081-19 M008 Room 126-metallurgical
Laboratory (on cabinets under
laboratory hood)
NDTransite Panel
AB-A1081-20 M009 Room 116-Coffee Area NDCove Base Adhesive
AB-A1081-21 M010 Room 127-Chemical Laboratory NDDuct Sealant
Note: ND =No Asbestos Detected, NA= Not Analyzed, TR = <1% Asbestos, PC = Point Count
Asbestos Survey Report - Table 3 Page 2 of 2 Administration Building
White Mesa Mill-Denison Mines Corp
Table 4
Bulk Sample Analytical Results by Homogeneous Area Number
White Mesa Mill-Denison Mines Corp
Administration Building
Homogeneous
Area Number Material Sampled Analytical ResultsSample
Number Sample Location
AB-A1081-01 M001 Room 107-Safety Office NDWall System
AB-A1081-02 M001 Room 122-Men's Restroom NDWall System
AB-A1081-03 M001 Room 126-Metallurgical
Laboratory
NDWall System
AB-A1081-04 M002 Room 107-Safety Office NDCeiling Tile
AB-A1081-05 M002 Room 122-Men's Restroom NDCeiling Tile
AB-A1081-06 M002 Room 127-Chemical Laboratory NDCeiling Tile
AB-A1081-07 M003 Room 116-Coffee Area NDCeiling Tile
AB-A1081-08 M003 Room 119-Training Room NDCeiling Tile
AB-A1081-09 M003 Room 126-Metallurgical
Laboratory
NDCeiling Tile
AB-A1081-10 M004 Room 116-Coffee Area 5%
>1%
Chrysotile-tile
Chrysotile-
mastic
Floor Tile and Mastic
on Cement
AB-A1081-11 M004 Room 120-Custodial Closet 5%
>1%
Chrysotile-tile
Chrysotile-
mastic
Floor Tile and Mastic
on Cement
AB-A1081-12 M004 Room 100-Waiting Area 5%
>1%
Chrysotile-tile
Chrysotile-
mastic
Floor Tile and Mastic
on Cement
AB-A1081-13 M005 Room 111-Conference Room 5%Chrysotile-tileFloor Tile and Mastic
on Cement
AB-A1081-14 M005 Room 121-Bioassay Room 5%Chrysotile-tileFloor Tile and Mastic
on Cement
AB-A1081-15 M005A Room 121-Bioassay Room 6%ChrysotileFloor Tile Mastic
Asbestos Survey Report - Table 4 Page 1 of 2 Administration Building
White Mesa Mill-Denison Mines Corp
Homogeneous
Area Number Material Sampled Analytical ResultsSample
Number Sample Location
AB-A1081-16 M006 Room 118-Women's Restroom
>1%
ND-tile
Chrysotile-
mastic
Floor Tile and Mastic
on Cement
AB-A1081-17 M006 Room 122-Men's Restroom
>1%
ND-tile
Chrysotile-
mastic
Floor Tile and Mastic
on Cement
AB-A1081-18 M007 Room 127F-Chief Chemist
Office
ND-tileFloor Tile-Exposed
AB-A1081-19 M008 Room 126-metallurgical
Laboratory (on cabinets under
laboratory hood)
NDTransite Panel
AB-A1081-20 M009 Room 116-Coffee Area NDCove Base Adhesive
AB-A1081-21 M010 Room 127-Chemical Laboratory NDDuct Sealant
Note: ND =No Asbestos Detected, NA= Not Analyzed, TR = <1% Asbestos, PC = Point Count
Asbestos Survey Report - Table 4 Page 2 of 2 Administration Building
White Mesa Mill-Denison Mines Corp
Table 5
Damage and Hazard Assessment by Homogeneous Area
White Mesa Mill-Denison Mines Corp
Administration Building
Homogeneous
Area Number DamageSubstrate AccessibilityMaterial
Type
Assessment
Category
Disturbance
Potential
M004 X No Damage ContinuousCement LowFloor Tile and Mastic
on Cement
M005 X No Damage ContinuousCement LowFloor Tile and Mastic
on Cement
M005A X No Damage Rarely AccessedCement LowFloor Tile Mastic
M006 X No Damage ContinuousCement LowFloor Tile and Mastic
on Cement
M007 X No Damage ContinuousCement LowFloor Tile-Exposed
Asbestos Survey Report - Table 5 Page 1 of 2 Administration Building
White Mesa Mill-Denison Mines Corp
Table 6
Estimated Abatement Costs by Homogeneous Area
White Mesa Mill-Denison Mines Corp
Administration Building
Homogeneous
Area Number Material Extended
CostAmountUnit Cost
M004 Floor Tile and Mastic on Cement 1,395 sq. ft.$3.36 $4,687
M005 Floor Tile and Mastic on Cement 6,380 sq. ft.$3.36 $21,437
M005A Floor Tile Mastic Under Non-AC 1,440 sq. ft.$3.36 $4,838
M006 Floor Tile and Mastic on Cement 185 sq. ft.$3.36 $622
M007 Floor Tile-Exposed 1,600 sq. ft.$2.52 $4,032
Total Estimated Abatement Cost $35,616
Note: Estimated abatement costs do not include replacement costs or costs for a consultant to manage the abatement.
Asbestos Survey Report - Table 6 Page 1 of 1 Administration Building
White Mesa Mill-Denison Mines Corp
Homogeneous
Area Number DamageSubstrate AccessibilityMaterial
Type
Assessment
Category
Disturbance
Potential
Damage Categories
Each homogeneous area of ACM was classified into one of the following seven categories, as specified in
EPA’s AHERA regulations (40 CFR §763.88):
(1) Damaged or significantly damaged thermal system insulation ACM.
(2) Damaged friable surfacing ACM.
(3) Significantly damaged friable surfacing ACM.
(4) Damaged or significantly damaged friable miscellaneous ACM.
(5) ACBM with potential for damage.
(6) ACBM with potential for significant damage.
(7) Any remaining friable ACBM or friable suspected ACBM.
(X) Not applicable (material is non-friable surfacing or miscellaneous material).

The damage categories are defined as follows:
“Undamaged” means the material had no visible damage, or extremely minor damage or surface
marring (i.e., a room full of floor tile with only two or three small corners chipped off of the tile).
“Slight Damage” means the material had visible damage evenly distributed over less than 10% of its
surface, or localized over less than 25% of its surface.
“Significantly Damaged” means the material had visible damage that is evenly distributed over 10% or
more of its surface or localized over 25% or more of its surface.

Hazard Assessment Categories
Each homogeneous area of ACM was evaluated for accessibility and the hazard the material presents to
building occupants and the general public. The assessment assumes a fully occupied building.
“Inaccessible” means the material was located in an area that people had no reason to enter and could
not access without special measures. One example would be above a solid ceiling.
“Rarely-Accessed” identifies a material that was in a location that could be accessed but wasn't unless
there was a specific needed. An example would be a pipe tunnel. Another example would be a high
ceiling that is out of reach and not subject to any specific disturbances.
“Periodic Access” identifies a material that was in a location that was accessible, was not occupied full
time, but was accessed on a routine basis. An example would be a mechanical room or boiler room.
“Continuous Access” identifies a material that was in a location that was occupied full time and was
within reach of the occupants, or was frequently subject to direct disturbance. Examples would be
exposed floor tile or a normal height ceiling.
Asbestos Survey Report - Table 5 Page 2 of 2 Administration Building
White Mesa Mill-Denison Mines Corp

Appendix B
Building Floor Plans

127
127F 127D 127B
127G
127E 127C 127A
126100C 126B
126A
124 125 122
120
118119
121
121A
123
123A
107 105 103 101
117
100B
116
109 111 113
115114112110100
100A
102104106108
19 6 18
21
9
3
17
5
2
11
16
7
20
10
8
14
15
4
1
12
13
Sample Location & Number10
Room Number
Explanation
101
Asbestos-containing Floor Tile & Mastic
Asbestos-containing Floor Mastic
PROJECT No:
SHEET:
DRAWN BY:
REVIEWED BY:
De
n
i
s
o
n

M
i
n
e
s

C
o
r
p
.
Wh
i
t
e

M
e
s
a

M
i
l
l
64
2
5

S
o
u
t
h

H
i
g
h
w
a
y

1
9
1
Bl
a
n
d
i
n
g
,
U
T
As
b
e
s
t
o
s

&

H
a
z
a
r
d
o
u
s

M
a
t
e
r
i
a
l
s

S
a
m
p
l
e

L
o
c
a
t
i
o
n

M
a
p
DATE:
DATE:
DATE:
REVISED BY:
640 E. Wilmington Ave.
Salt Lake City, UT 84106801.466.2223
[e-mail]
0 5'10'
12U-A1081
1 of 1
Keith
07-11-2012

V:\
-

1
2

P
r
o
j
e
c
t
s
\
1
2
U
-
A
1
0
8
1

D
e
n
i
s
o
n

M
i
l
l

S
i
t
e

A
s
b
e
s
t
o
s

I
n
s
p

&

M
P
\
D
r
a
w
i
n
g
s
\
1
2
U
A
1
0
8
1
.
d
w
g
,

a
d
m
i
n
i
s
t
r
a
t
i
o
n
,

7
/
1
1
/
2
0
1
2

4
:
2
5
:
1
2

P
M
,

k
e
i
t
h
f
,

A
N
S
I

f
u
l
l

b
l
e
e
d

B

(
1
7
.
0
0

x

1
1
.
0
0

I
n
c
h
e
s
)

Appendix C
Photographs

Photograph 1
The wall system did not contain asbestos.
Photograph 2
All of the ceiling panels in the Administration
Building were reported as none detected for asbestos.

Photograph 3
The flooring that consists of vinyl floor tiles and black
mastic contained >1% to 5% chrysotile asbestos.
Photograph 4
These suspect panels used under the laboratory hood
cabinets did not contain asbestos.

Photograph 5
The cove base adhesive did not contain asbestos.
Photograph 6
This gray duct sealant was reported as none detected
for asbestos.

Appendix D
Laboratory Results

DIXON INFORMATION INC.----------.
MICROSCOPY,ASBESTOS ANALYSIS &CONSULTING
A.I.H.A.ACCREDITED LABORATORY #101579
NVLAP LAB CODE 101012-0
June 14, 2012
Mr.Lono Folau
IHI Environmental
640 East Wilmington Ave
Salt Lake City, UT 84 106
Ref: Batch # 104899,Lab #HI 9703 -H1 9723
Received June 6.2012
Test report,Page I of 5
Denison Mines Corp .
White Mesa Mill Administration Building
6425 S.Highway 191,Blanding, Utah
Proj#12 U-A108 1
Sampled by Lono Folau,5/3 1/2012
Dear Mr. Folau:
Samples H19703 through H19723 have been analyzed by visual estimation based on EPA-
600/M4-82-020 December 1982 optical microscopy test method, with guidance from the
EPA/6001R-93/116July 1993 and OSHA ID 191 methods.Appendix "A"contains statementswhich
an accredited laboratory must make to meet the requirements of accrediting agencies.It also
contains additionalinformation about the method of analysis.This analysis is accredited byNVLAP.
Appendix "A"must be included as an essential part of this test report.The data for this report is
accredited by NVLAP for laboratory number 10I012-0.It does notcontain data or calibrations for
tests performed under the AIHA program under lab code 101579.
This report may be reprod uced but all reproduction must be in full unless written approval
is received from the laboratory for partial reproduction.The results of analysis are as follows:
Lab H19703.Field AB-AI081-1 Wall System
This sample contains white paint,white limestone and gypsum plaster with fine mica,tan plantfiber
paper,and white gypsum plaster with 1%fiberglass and 1%plant fiber.This sample is non-
homogeneous.Asbestos is none detected.
The paint is I%of the sample.The plaster with mica is 2%of the sample. The plant fiber paper is
3%of the sample. The white gypsum plaster is 94 %of the sample.
'--t-----78 WES T 2400 SOUTH ·SOUTH SALT LAKE,UTAH 84115-3013
PHONE [phone] · FAX [phone] · RES.80 1-571-7695 .....J
Batch #104899
Lab #H19703 -H 19723
Page '2 of 5
Lab H19704. Field AB-A I08 1-2 W all System
Th is sample contains white paint. whitc gypsum plaster w ith fine mica.tan plant fiber paper,and
white gypsum plaster with I%fiberglass.This sample is non-homogeneou s.As bestos is none
detect ed.
The paint is I%of the sample. The plaster with fine mica is 2%of the sample. Th e plant fibe r paper
is 3%of the sample.The white gypsum plaster is 94 %of the sam ple.
Lab H19705.Field AB-A 1081-3 Wa ll System
Thi s sample co ntains white gypsum plaster with fine mica.tan and white plant fiber paper.and white
gypsum plaster with I%fiberglass and 1%plant fiber.This sample is non-homogeneous.Asbestos
is non c detected ,
The plaster with mica is 2%of the sample.The plant fiber paper is 23%of the sample.The whit e
gypsum plaster is 75 %of the sample.
Lab H I970f>.Field AB-A I08 1-4 Ce iling Tile (I )
This is a light gray sample with perlite.30%plant fiber.and 30%mineral woo l in resin binder with
a white coating on one side.As hestos is none detect ed.
The white coa ting is 1%of the sample.
Lab H19707.Field AB-A 108 1-5 Ceiling Tile (I )
Th is is a light gray sample with perlite,25%plant fiber.and 30%mineral woo l in resin binder with
a white coa ting on one side.Asbes tos is none detected .
The white coating is I%of the sample.
Lab H 19708.Field A B-A I08 1-6 Ce iling T ile (1)
Thi s is a light gray sample with perlite. 25%plant fiber,and 35 %mineral woo l in resin binder with
a white coating on o ne side.Asbestos is none d etected .
The white coating is I%of the sample.
Lab H19709.Field AB-A 108 1-7 Ce iling T ile (2)
Th is is a ligh t gra y sample with perlite.20%plant fiber.and 15%mineral woo l in resin binder with
a white coating on one side.Asbestos is none d etected.
The white coating is I%of the sample.
Batch #104899
Lab #H 19703 -H19723
Page 3 of 5
Lab H I97J O,Field A B-A J08 1-8 Ceiling Tile (2)
Thi s is a light gray sample with per lite,20 %plant fiber.and J5%mineral wool in resin bin der with
a white coating on one s ide.Ashestos is none detected.
Th e white coating is 1%o f the sample.
Lab HI 97 Jl.Field A13-AI 08 1-9 Ceiling Tile (2)
This is a light gray sample with perlite.20%plant fiber.and 20%minera l wool in resin binder with
a wh ite coating on one side.Asbestos is none detected .
The white coating is %of the sample,
Lab H 19712,Field AB-A I08 1-10 Floor Tile (I)
Thi s is 5 %chrysotilc as bestos in a tan plastic and limestone tile.
Note: Th e black mastic contains greater th an 1%chrysotlle ashesto s.
The tile is grea ter than 99%of the sample. The b lack mastic is less than I%of the sample,
Note :The morphology of the fibers in the plastic and limestone tile are consistent w ith chrysotile
asbestos.Fiber size is too small for identi fication by measurement of refractive indices.
Transmission Electron Mi croscop y (TEM)is recommended for final confirmation that this is
chrysotilc asbestos.
Lab H 197 13, Field AB-A 108 1-11 Floo r Ti le (I)
Th is is 5 %ch rysotile asbestos in a tan plastic and limestone tile,
Note:The black mastic co ntains greater th an 1%chrysotile as bestos,
The tile is greater than 99%of the sample,The black mastic is less tha n I%of the sample,
The anal ysis sens itivity is limited in the black tar material type due to trace layer.
Note:The morphology of the fibers in the plastic and limestone tile are consistent with chrysotile
asbestos.Fiber size is too small for identification by measurement of refractive indices.
Transmission Electron 'Microscopy (TEM) is recommended for final co nfirmatio n that this is
chrysotile asbestos,
Butch #104899
Lab #1-11 9703 -1-11 9723
Page 4 of 5
Lab 1-1 197 14.Field AB-AI 081-12 Floor T ile (I)Mastic
This is 5 %chrysotile asbestos in an off-white plastic and limestone tile.
Note:The black mastic co ntains greater than 1%chrysoti le ashestos.
Th e tile is 99%of the sample.The black mastic is I%of the sample.
Lab 1-1 19715. Field AB-A 1081-13 Floor Tile (2)
Thi s is 5 %chrysotile as bestos in an off-white plastic and limestone tile.
Note:j 0 mastic.
Note:The morphology of the fibers in the plastic and limestone tile are consistcnt with chrysotile
asbestos.Fiber s ize is too small for identification by measurement of refr active indices.
Transmission Electron Microscopy (TEM) is recommended for final confirmation that thi s is
chrysotile asb estos.
Lab 1-1 197 16. Field AB-A I08 1-14 Floor Ti le (2)
This is 5 %chrysotile as bestos in off-white plastic and limestone tile with surface debris.
Note: The morphology.of the fibers in the plastic and limestone tile are consistent with chrysotile
asbestos.Fiber size is too small for identi fication by measurement of refractive indices.
Transmi ssion Electron Microscopy (TEM)is recommended for final confirmation that this is
chrysotile asbestos.
Lab 1-11 9717. Field AB-A I081-15 Floor Tile (2) Mastic
This sample co ntains three types of material:Th e first type is white plaster;the second type is 6%
chrysotlle as bestos in black tar:the third type is red binder.Th is sample is non-homogeneous,
The first type is 40 %of the sample.The second type is 55%of the sample. Th e third type is 5'70 of
thc sample.
Lab 1-11 97 18.Fie ld AB-A1081-16 Floor Ti le (3) And Mastic
Thi s sample co ntains three types of material:Th e first type is light gra y plastic and limestone tile:
the second typ e is yellow resin mastic;the third type is greater th an 1%chrysotile asbestos in
black tar mastic.Thi s sample is non -homogeneous.
The first type is 98%of the sample .The second type is 1'70 of the sample,Th e third type is I%of
the sample.
Batch #104899
Lab #H 19703 -H19723
Page 5 of 5
Lab H 197 19,Field AB-A I08 1-17 Floor Ti le (3)And Mastic
Thi s sample contains three types of material:The first type is light gray plastic and limestone;the
second type is yellow resin mastic;the third type is greater than 1%chrysotile asbestos in black
tar.Th is sample is non-homogeneous.
The first type is greater than 98%of the sample,The second type is 1%of the sample,The third
type is less than I%of the sample.
Lab HI 9720, Field AB-'AI081-18 Floor Tile (4)
This is a white plastic and limestone tile.Asbestos is none detected.
Note: No mastic,
Lab HI 972 \, Field AB-A I08 1-19 Transite Panel
This is 10%plant fiber in hard gray cement. Asbestos is non e d etected.
Lab H19722,Field AB-A 1081-20 Cove Base And Adhesive
This sample contains two types of material:The first type is brown rubber and limestone;thesecond
type is brown resin mastic.This sample is non-homogeneous,Asbestos is none detected.
The first type is 99%of the sample.The second type is I%of the sample,
Lab H19723,Field AB-A1081-21 Duct Sealant
Th is is gray sealant with limestone and particulate.Asbestos is none detected .
In order to be sure reagents and tool s used for ana lysis are not contaminated with asbestos,
blanks are tested.Asbestos was none detected in the blanks tested with this bulk sample set.
Very truly yours,
Steve H.Dixon,President
Analyst:Steve H.DiXOl;~~-'f=Date Analyzed:June 14,2012
Dixon Information Inc.
78 W est 2400 South
South Salt Lake, Utah 84115
Phone:[phone] Fax:[phone]
BULKANALYTICAL REQUEST FORM
Turnaround Time -Circle One Batch Number /0 4 f'ffCJ
Ru sh (24 hours $25.00 per sample)
~Non-rush (5 Working days $17.00 per sample)
pen;son 1v1;....e~Co,"/-,-GJh ire M~S;o-A<.ft
Name oflocation sample was taken at Ad,...i"i$f,.."dlon.l3u ;/</i/?e?
Streetaddress sample was taken at t:.t'ZS S ...JI~A.u¥/9 1 ,B I....:d;"Y .U T
Sampled by:Lone FoI~
Lab #
ftV-AIOBI
Samples Collected
Date TimeDescriptionofSampleField#
A.B-A/OSI
I
Z
3
Report to be sent to:.t~n D ~Iau..Billing to be sent to:=o---;----,,---,__
Company:1/71 5"Y;r-on ""en:taL Company:lIT/E/iv/ronnu.l7taL
Address:t:.£!''£1t/;/",.;"dt.:¥1AYe Address:_
City:,su..State:rJr City:,,.----,State:_
Zip Code:g l{I ()~Zip Code:--:-:-_
Telephone #:flOI'¥b 6 ..Z:12 J Telephone #:,_
Fax #:go I·'16 6 •?t,/(,Fax #:_---;__-__---=-:__----
E-mail:IfOlaU@/hi.enY.tom PO #:_-L~'------'-'-'__=__"'_'___
7
g
9
/0 F loov'"·H /e CI)
Chain of Custody
Date:'/~)J z...Time:_
Date:(,-1,-!b Time:)'\·XS
Date :b -l :l .(J Time:II ~Cl
Date:Time:_
Submission of asbestos samples for analysis and/or signing a chain of custody is the
equivalent of submission of a purchase order and constitutes an agreement to pay for services
provided at Dixon Information Incorporated standard schedule offees for services.
Submitted by:~~.
Received by U6 ~~~
Received by Analyst:~=~;;*'i------
Returned by Lab:_
Dixon Information Inc.
78 West 2400 South
South Salt Lake,Utah 84115
Phone:[phone] Fax:[phone]
BULKANALYTICAL REQUEST FORM
Turnaround Time -Circle One Batch Number ;048")<:"j
Rush (24 hours $25.00 persample)
Non-rush (5 Working days $17 .00 per sample)
{Jen;$on 1v1;..*,~CO"f"t.Jhi ;'e ~~o-.It(.ft
Name oflocation sample wastakenat Ad,..i"isf,.alion./3";/./b7~
Streetaddress sample wastaken at I:.+,ZS s ....J,t&A",,~19 I .6'I "'::d;~"'.UT
Sampledby:L on o FoIa-<,A...
Lab #
/2t.J-AIOBI
Samples Collected
Date TimeDescriptionofSample
;:'/001'r'11e CI)
;::'/00"f"-Ie.(I)M<lS f i Co
F/DM .(;'Ie (20)
EI'Ddf tiIe.(ZJ
FloO('tf Ie.,...J /Yla>~:G
AoQr'tde (5)a"".;J _sf/G
r-Iu'l -('de {]J -.J _s;';c.
£Ioo r /'i'It!.eO
7Yans;i~p",...e I
L r 'I.Cove puc ~MlHes;ve
Owe:!UJ.ll!Uft-
Reportto be sent to:t~n D J=;;,/au.-Billing to be sentto:,=---,--,,---,--,_
Company:IIt'I E"Y;'-Dn l'Me#1:taL Company:If(/E/lV'/rannu.l?faL
Address:'i""E Itj(/"..;Aafz:vl.Ave Address:---=_
City:,su..State:'tiT City:::--;State:_
Zip Code:g 'II /)~Zip Code:_
Telephone #:XO/·'/66-Z.2Z'J Telephone#:_
Fax#:gO/-'166 -9(, 16 Fax#:_-----:-.,..-_
E-mail:h'O/au@ilti-enV.~In PO #:_-L......"~L.'-':.::..~=_--,,..._--
Field #
AS-AIM J.
II
1 2.
/do
1"1
IS'
/~
17
I~
/9
'2.0
2.1
Chain of Custody
Submission of asbestos samples for analysis and/or signing a chain of custody is the
equivalent of submission of a purchase order and constitutes an agreement to pay for services
provided at Dixon Information Inco orated standard schedule offees for services.
Submitted by:-:;;>~~l,.."."¥;".:;.=~----­
Received by
Received by AnaJyst.';;;:;~i.L-L...'.....!.f~-----
Returned byLab:_
Appendix "A"
"This report relates only to the items tested.This report must not be used to claim
product endorsement by NVLAP or AIHA."
NVLA P and AIHA requires laboratories to state the condition of samplcs received for
testing:These samples are in acceptable condition for analysis unless there is a statement
in the report of analysis that a test item has some characte ristics or condition that
precludes analysis or requires a modification ofstandard analytical methodology,If a test
item is not acc eptable,the reasons for non-acceptability will be given under the
laboratory number for that particular test item.The reported percentages of each material
type arc based on the sample received by the laboratory and may not be representative of
the parent material. Orientation of top and bottom may not be specified due to uncertainty
oforientation.
Methods of Analysis and Limit of Detection
In air count analysis.the results may be biased when interferences arc noted.
The accuracy of asbestos analysis in bulk samples increases with increasing
concentration of asbestos.Pigments.binders. small sample size. and multiple layers may
affect the analysis sensitivity.
There arc two methods for analysis of asbestos in a bulk test sample.Visual
estimation is the most sensitive method.If an analyst makes a patient search. 0.1 %or Icss
asbestos can be detected in a bulk sample.
The sceond method of analysis is a statistical approach called point counting. EPA
will not accept visual estimations if a laboratory detects a trace of asbestos in a sample
i.e.anything less than I%asbestos.Government agencies regulate asbestos containing
materials (ACM)whenever the ACM is more than I%.OSHA requirements apply on
samples containing any amount ofasbestos.
Due to the higher charge for a point count analysis,Dixon Information Inc.does not
perform a point count unless authorized to do so by the client.If a sample is point
counted.when possible. various chemical and/or physical means may be used to
concentrate the asbestos in the sample. This is permitted by the EPA method and it
increases the accuracy of the analysis.

Appendix E
Regulatory Factors

Several factors determine how asbestos in a building must be treated if it has the potential of
being disturbed during a renovation or demolition. These factors include the following:

Factor
EPA Regulations for
Asbestos Removal
OSHA Regulations for
Asbestos Removal
Definition of asbestos
in a building material
Defines ACM as a material
containing 1% or greater asbestos.
Defines an ACM as one containing
>1% asbestos.
Regulation of asbestos
in building materials
Regulates only ACM. If the asbestos
concentration in a material is shown
to be “none detected” by initial
analysis or 1% or less by point count
analysis, EPA/DAQ does not regulate
it.
Regulates not only ACM but all
materials containing any amount of
asbestos. Regulations are not as
stringent for materials containing
equal-to or less-than 1% asbestos but
greater than a “none detected”
concentration.
Determination of
asbestos concentration
in a gypsum board
wall system
Allows compositing of all layers
(joint compound, joint tape, and
gypsum board) into one sample,
which decreases the possibility that
the sample will be evaluated as an
ACM.
Requires that each layer of the wall
system be analyzed and reported
independently, which increases the
possibility of a sample containing
ACM or identifiable asbestos.
Defines regulated and
non-regulated ACM
Yes – Regulated ACM include friable
ACM and resilient flooring, asphalt
roofing, gaskets and packing that
have become friable and other ACM
that have a high probability of
becoming friable.
No – Requirements for asbestos work
procedures and worker training are
less stringent for resilient flooring,
asphalt roofing materials, and
materials containing greater than
“none detected” but not greater than
1% asbestos.
Notification of
asbestos abatement or
building demolition
required
Yes – Utah DAQ must be notified on
the appropriate form 10 working-days
prior to an asbestos abatement of
regulated asbestos material greater
than the NESHAP-established
notifiable quantity with demolition, or
demolition where abatement is not
required.
No – Not required.
Provision for allowing
ACM to remain in a
building during a
demolition.
Yes – Allows ACM resilient flooring,
asphalt roofing, and certain other non-
friable building materials in good
condition to remain in a building
during demolition as long as the
demolition process will not render
them friable.
No – If any asbestos is left in a
building during a demolition, the
demolition workers are expected to
meet the same OSHA requirements
that an abatement contractor would
meet if an abatement contractor was
conducting an abatement of those
materials.

Appendix F
Project Limitations

PROJECT LIMITATIONS
This Project was performed using, as a minimum, practices consistent with standards
acceptable within the industry at this time, and a level of diligence typically exercised by
EH&S consultants performing similar services.
The procedures used attempt to establish a balance between the competing goals of limiting
investigative and reporting costs and time, and reducing the uncertainty about unknown
conditions. Therefore, because the findings of this report were derived from the scope, costs,
time and other limitations, the conclusions should not be construed as a guarantee that all
universal, toxic and/or hazardous wastes have been identified and fully evaluated.
Furthermore, IHI assumes no responsibility for omissions or errors resulting from inaccurate
information, or data, provided by sources outside of IHI or from omissions or errors in public
records.
It is emphasized that the final decision on how much risk to accept always remains with the
client since IHI is not in a position to fully understand all of the client's needs. Clients with a
greater aversion to risk may want to take additional actions while others, with less aversion to
risk, may want to take no further action.

ATTACHMENT A.2

MILL BUILDING, BOILER PLANT, SCALE HOUSE, AND THE SAMPLE PLANT
ASBESTOS INSPECTION REPORT

IIHHII
E NVIRONMENTAL

ASBESTOS INSPECTION REPORT

Mill-Boiler Plant-Scale House-Sample Plant
White Mesa Mill-Denison Mines Corp
6425 S. Highway 191
Blanding, Utah 84511

August 1, 2012

Prepared for:
Ms. Jo Ann Tischler, Corporate Director of Compliance & Permitting
Denison Mines
1050 17th Street, Suite 950
Denver, Colorado 80265

Prepared by: Reviewed by:

Lono Folau
Asbestos Inspector #ASB-0537
Jon H. Self
Asbestos Program Manager

IHI Project 12U-A1081
640 EAST WILMINGTON AVE SALT LAKE CITY UT 84106 TELEPHONE: [phone] FAX: [phone] E-MAIL: [e-mail]

SALT LAKE CITY SAN FRANCISCO PHOENIX DENVER SEATTLE

TABLE OF CONTENTS

EXECUTIVE SUMMARY .............................................................................................................. I 
1.0 INTRODUCTION ..............................................................................................................1 
2.0  BUILDINGS DESCRIPTION ..............................................................................................1 
3.0 INSPECTION PROCEDURES ............................................................................................2 
3.1 Asbestos-Containing Material (ACM) ...............................................................2 
3.2 Bulk Sampling ...................................................................................................3 
3.3 Bulk Sample Analysis ........................................................................................3 
4.0 INSPECTION RESULTS ....................................................................................................4 
4.1 Asbestos-Containing Materials ..........................................................................4 
4.2 Non-Asbestos-Containing Materials ..................................................................5 
4.3 Bulk Sample Analytical Results ........................................................................5 
4.4 Damage and Hazard Assessment .......................................................................5 
4.5 Materials Requiring Special Considerations ......................................................5 
4.6 Assumed Asbestos-Containing Materials ..........................................................6 
4.7 Inaccessible Areas ..............................................................................................6 
4.8 Materials Assumed >1% Asbestos (no NESHAP point count) .........................6 
5.0 RESPONSE ACTIONS ......................................................................................................6 
5.1 Applicable Rules and Regulations .....................................................................6 
5.2  Renovation and Demolition (EPA and OSHA) .................................................7 
6.0 COST ESTIMATES ..........................................................................................................7 

APPENDICES

Appendix A: Data Tables
Appendix B: Building Floor Plans
Appendix C: Photographs
Appendix D: Laboratory Results
Appendix E: Asbestos Regulatory Factors
Appendix F: Project Limitations

Mill-Boiler-Scale House-White Mesa Mill TOC - 1 IHI Environmental
Denison Mines Asbestos Inspection Project No. 12U-A1081

EXECUTIVE SUMMARY
On May 31, 2012, IHI Environmental conducted an asbestos inspection of the Mill Building,
Boiler Plant, Scale House and the Sample Plant at the Denison Mines White Mesa Mill in
Blanding, Utah. Ms. Jo Ann Tischler, Corporate Director of Compliance and Permitting,
requested this inspection to identify asbestos-containing materials (ACM) that exist in the
building.
• No asbestos-containing material was identified in these buildings.
The suspect asbestos materials identified in these buildings included wall systems on the
second level of the Mill Building, floor tiles on the second floor of the Mill Building and the
Scale House, and gasketing on the boiler in the Boiler Plant. No suspect asbestos material
was identified in the Sample Plant.
The report that follows this Executive Summary should be read in its entirety because it
includes important information, such as material descriptions and locations, regulatory
requirements, and building-specific recommended response actions.
Mill-Boiler-Scale House-White Mesa Mill i IHI Environmental
Denison Mines Asbestos Inspection Project No. 12U-A1081
Executive Summary
Asbestos-containing Materials by Homogeneous Area
White Mesa Mill-Denison Mines Corp
Warehouse-Maintenance Building
Homogeneous
Area Number Material Description/Location Asbestos
Content Amount Cost
Estimate(1)
M004 12-15%
>1-8%
2,140 sq. ft.Chrysotile:
tile
Chrysotile:
mastic106A, 107C, 107D-Offices and 200-Lunch
Room
Floor Tile and Mastic on Cement - 12" x
12" Tan vinyl floor tile and black mastic
$7,190
M004A 8%420 sq. ft.Chrysotile
107A-Instrument Shop/Tool Room
Floor Tile Mastic Under Non-ACM
Coverings - Black tar mastic
$1,411
Cost Estimates include asbestos removal costs only; abatement design, management fees and
replacement costs are not included. Please refer to Section 6.0 for more details.
Note 1:
Executive Summary Table Warehouse-Maintenance Building
White Mesa Mill-Denison Mines Corp
Page 1 of 1

ASBESTOS INSPECTION

Mill-Boiler-Scale House
White Mesa Mill-Denison Mines Corp
6425 S. Highway 191
Blanding, Utah

1.0 INTRODUCTION
On May 30, 2012, IHI Environmental conducted an asbestos inspection of the Mill Building,
Boiler Plant, Scale House and the Sample Plant of the White Mesa Mill in Blanding, Utah.
Ms. Jo Ann Tischler, of Denison Mines, requested this inspection to identify asbestos-
containing materials (ACM) that exist in the facility.
2.0 BUILDINGS DESCRIPTION
• Buildings Identification
Buildings Name ...........................Mill Building, Boiler Plant, Scale House, and
Sample Plant
Buildings Address .......................6425 South Highway 191, Blanding, Utah 84511
• Building Construction
Buildings Construction Date ........circa 1978
Renovations..................................Not known
Building Type .............................Plant, offices, boiler
Buildings Total Sq. Ft. .................33,330 square feet (Mill Building),
2,500 square feet (Boiler Plant),
400 square feet (Scale House),
1,250 square feet (Sample Plant)
Structural System ........................Concrete foundation with steel (Mill Building
and Boiler Plant), wood (Scale House), and
concrete with brick (Sample Plant)
Exterior Wall Construction .........Metal (Mill Building and Boiler Plant), wood
(Scale House), and brick (Sample Plant)
Floor Deck Construction .............Concrete (Mill Building, Boiler and Sample
Plants), wood (Scale House)
Roof Deck Construction .............Metal (Mill Building, Boiler Plant, and Sample
Plant), wood (Scale House)
Mill-Boiler-Scale House-White Mesa Mill 1 IHI Environmental
Denison Mines Asbestos Inspection Project No. 12U-A1081

Roof Construction .......................Metal (all buildings)
• Floors
Floors Above Grade .................... One (except Mill Building-offices on second
level)
Floors Below Grade .................... None
• Interior Finishes
Floors ...........................................Concrete (Mill Building, Boiler and Sample
Plant), vinyl floor tile (Scale House and Mill
Building second level)
Walls ............................................ Metal (Mill Building and Boiler Plant), brick
(Sample Plant), wood (Scale House), and wall
system (Mill Building second level)
Ceilings ........................................ Metal (Mill Building and Boiler Plant), brick
(Sample Plant), wood (Scale House), and wall
system (Mill Building second level)
Attic ............................................. None
Basement ..................................... None
• Building Mechanical
Heating Plant ............................... Not known
Cooling Plant ............................... Roof units
3.0 INSPECTION PROCEDURES
3.1 Asbestos-Containing Material (ACM)
IHI visually inspected all accessible areas of the building to identify suspect ACM. To assess
the condition and determine friability of the suspect materials, IHI visually examined and
touched all accessible surfaces, structures, and mechanical systems within the building.
Suspect ACM was identified and assessed by homogeneous areas. A homogeneous area is
defined as a single material, uniform in texture and appearance, installed at one time, and
unlikely to consist of more than one type, or formulation, of material. In cases where joint
compound and/or tape has been applied to wallboard (gypsum board) and cannot be visually
distinguished from the wallboard, it is considered an integral part of the wallboard and in
effect becomes one material forming a wall or ceiling “system."
Mill-Boiler-Scale House-White Mesa Mill 2 IHI Environmental
Denison Mines Asbestos Inspection Project No. 12U-A1081

Each homogeneous area was given a unique material identification (ID) number. Each ID
number begins with a letter: "S" for surfacing materials, "T" for thermal system insulation, or
"M" for miscellaneous materials. This letter is followed by a three-digit number, assigned in
consecutive order. This number is used to identify that specific homogeneous area
throughout the inspection report.
3.2 Bulk Sampling
To determine the asbestos content of materials, IHI collected bulk samples from all
accessible homogeneous areas of suspect ACM and submitted the samples to an accredited
laboratory for analysis.
The number of samples collected from each homogeneous area generally followed the U. S.
Environmental Protection Agency (EPA) Asbestos Hazard Emergency Response Act
(AHERA) regulations (40 CFR §763.86). Friable surfacing materials were sampled using the
random sampling scheme given in the EPA publication 560/5-85-030a, titled "Asbestos in
Buildings: Simplified Sampling Scheme for Friable Surfacing Materials." Bulk sample IDs
collected during the inspection were entered on chain-of-custody forms for submittal to the
analytical laboratory.
3.3 Bulk Sample Analysis
Bulk samples were analyzed using polarized light microscopy (PLM) and visual estimation
according to the EPA Interim Method for the Determination of Asbestos in Bulk Insulation
Samples, EPA-600/M4-82-020. Samples were analyzed by Dixon Information Inc. in Salt
Lake City, Utah. Dixon Information is accredited under the National Institute of Standards
and Technology, National Voluntary Laboratory Accreditation Program (NIST-NVLAP) for
bulk asbestos sample analysis, and is also accredited by the American Industrial Hygiene
Association (AIHA).
EPA’s National Emissions Standards for Hazardous Air Pollutants (NESHAP) and AHERA
regulations define ACM as material containing greater than 1% asbestos by weight; materials
containing 1% or less asbestos are not considered regulated ACM by the EPA. Further, the
NESHAP regulations state that any sample found to contain less than 10% asbestos but
greater than “none detected," by the visual estimation method used during PLM analysis,
Mill-Boiler-Scale House-White Mesa Mill 3 IHI Environmental
Denison Mines Asbestos Inspection Project No. 12U-A1081

Mill-Boiler-Scale House-White Mesa Mill 4 IHI Environmental
Denison Mines Asbestos Inspection Project No. 12U-A1081
must be assumed to contain greater than 1% asbestos unless confirmed by NESHAP point
counting analysis.1
Despite EPA (and Utah Division of Air Quality) rules exempting building materials
containing 1% or less asbestos from stringent regulation, Occupational Safety and Health
Administration (OSHA) regulations outline specific precautionary work practices when
employees work with materials containing even trace amounts of asbestos.2
The laboratory reports can be found in Appendix D of this report.
4.0 INSPECTION RESULTS
4.1 Asbestos-Containing Materials
The Executive Summary and Table 1 in Appendix A list all homogeneous areas that contain
asbestos. Each material is described by type of material, friability and visual appearance.
Friability is defined in accordance with EPA’s NESHAP regulations.
• “Friable ACM” is any material containing more than 1% asbestos (as determined by
PLM) that, when dry, may be crumbled, pulverized, or reduced to powder by hand
pressure and also includes non-friable ACM that may become friable during building
demolition.
• “Non-friable ACM” is any material containing more than 1% asbestos (as determined
by PLM) that, when dry, cannot be crumbled, pulverized, or reduced to powder by
hand pressure.
• “Category I non-friable ACM” are asbestos-containing resilient floor coverings
(commonly known as vinyl asbestos tile (VAT)), asphalt roofing products, packings,
and gaskets.
• “Category II non-friable ACM” encompasses all other non-friable ACM.

1 NESHAP point counting includes examining materials under a polarizing microscope using an eyepiece
reticule that superimposes a grid of points over the field of view. 400 points are examined. 2 OSHA regulations pertaining to asbestos in buildings include 29 CFR 1926.1101 and 29 CFR 1910.1001.
OSHA has also issued interpretive letters that provide clarification about how materials containing less than 1%
asbestos should be handled. (see www.osha.gov)

• “Non-friable RACM” is used to denote thermal system insulation that is in good
condition but would become friable during renovation or demolition and therefore is
"regulated asbestos containing material" (RACM).
4.2 Non-Asbestos-Containing Materials
Homogeneous areas of suspect ACM are identified as non-ACM if material contains no
detectable asbestos. Table 2, located in Appendix A of this report, lists all homogeneous
areas that were found to be non-ACM.
4.3 Bulk Sample Analytical Results
Table 3, located in Appendix A of this report, lists all the bulk samples (chronologically by
sample number) collected from homogeneous areas of suspect ACM, and the laboratory
analytical results. Each sample was given a unique sample number. There may be more than
one sample number for the same homogeneous area of suspect ACM indicating multiple
samples were collected from that homogeneous material. The homogeneous areas of suspect
ACM are identified on this table by their material identification numbers. The sample
location listed on this table provides a brief, but specific, description of the location where
the sample was collected. This is different from the homogeneous area location provided on
Tables 1 and 2. Table 4 is the same as Table 3, except that the entries have been sorted by
homogeneous area number.
4.4 Damage and Hazard Assessment
Each homogeneous area of ACM was assessed for existing damage, accessibility, and
potential for future damage, this information is presented in Table 5, located in Appendix A
of this report. This table also lists the substrate beneath each homogeneous area of ACM.
Damage and hazard assessment categories are included in the tables in Appendix A.
4.5 Materials Requiring Special Considerations
The inside of the metal boiler and metal boiler flue could not be accessed during the
inspection.
Mill-Boiler-Scale House-White Mesa Mill 5 IHI Environmental
Denison Mines Asbestos Inspection Project No. 12U-A1081

Mill-Boiler-Scale House-White Mesa Mill 6 IHI Environmental
Denison Mines Asbestos Inspection Project No. 12U-A1081
4.6 Assumed Asbestos-Containing Materials
None
4.7 Inaccessible Areas
Suspect materials that were hidden or inaccessible may not have been characterized by this
inspection. Therefore, any material not identified in this report as having been tested should
be treated as suspect ACM until it has been sampled by a Utah-certified inspector and
analyzed by an accredited laboratory applying EPA methods.
In addition, some building structures may have been constructed after the application of
ACM, and therefore may have obscured these materials from visual examination during this
inspection. Typical scenarios include thermal system insulation inside hardened mechanical
chases, floor tile and mastic under walls, and sprayed-on texturing and fireproofing behind
structural supports or architectural features.
4.8 Materials Assumed >1% Asbestos (no NESHAP point count)
None
5.0 RESPONSE ACTIONS
5.1 Applicable Rules and Regulations
In Utah, EPA asbestos regulations are administered by the Utah Division of Air Quality
(DAQ).3 The Utah Occupational Safety and Health Administration (UOSH) has adopted the
Federal OSHA regulations.4 In addition, the Salt Lake Valley Health Department (SLVHD)
regulates demolition activities in Salt Lake County.5 The SLVHD regulations for pre-
demolition building inspections require an asbestos inspection, but also require building
owners to inspect the building for other hazardous materials such as universal wastes,
hazardous and toxic wastes, and lead-based paint. Like asbestos, these wastes, if present,
must be removed prior to building demolition.

3 R307-801. Asbestos, Utah Division of Air Quality Rules, Implementation of Toxic Substances Control Act
Title II, Asbestos Certification, Asbestos Training, notifications and Asbestos Work Practices for Renovations
and Demolitions (See www.airquality.utah.gov). 4 Asbestos, Tremolite, Anthophyllite, and Actinolite Standards, Chapter D (Construction), Section 58; and
Chapter Z (General Industry), Section 1001, Utah Occupational Safety and Health Rules and Regulations
(Administered by Utah Occupational Safety and Health Division) (See www.uosh.utah.gov). 5 Salt Lake City – County Health Department, Health Regulation #1 Section 12 (See www.slvhealth.org).

Mill-Boiler-Scale House-White Mesa Mill 7 IHI Environmental
Denison Mines Asbestos Inspection Project No. 12U-A1081

Regulatory factors relevant to asbestos abatement decision-making are included in Appendix E.
5.2 Renovation and Demolition (EPA and OSHA)
A listing of ACM found during this inspection is presented in the Executive Summary at the
front of this report, and in Appendix A, Table 1.
NESHAP regulations require the removal of friable ACM and non-friable ACM that could
become friable during demolition or renovation activities. Therefore, we recommend that all
of the ACM in this building be removed and properly disposed of by a licensed asbestos
abatement contractor if total demolition of the facility is planned, or those materials that will
be impacted by renovation plans be removed prior to the commencement of renovation work.
Despite EPA (and Utah Division of Air Quality) rules exempting building materials
containing 1% or less asbestos from stringent regulation, Occupational Safety and Health
Administration (OSHA) regulations outline specific precautionary work practices when
employees work with materials containing even trace amounts of asbestos.6 Strict
compliance by building owners with the OSHA asbestos regulations may result in response
actions not required by the EPA and Utah DAQ for certain unregulated materials.
6.0 COST ESTIMATES
Details of the estimated removal costs by homogeneous area can be found in Table 6,
Appendix A, and in the Executive Summary table. These estimates are provided for
budgeting and planning only, and do not have a level of accuracy sufficient to be used as a
construction design cost estimate. The actual cost of asbestos removal is dependent on
factors such as the size of the job, the required time frame for removal, the time of year the
job is conducted, and economic factors. These estimates do not include replacement costs, or
the cost for asbestos abatement design and management consulting services.

6 OSHA regulations pertaining to asbestos in buildings include 29 CFR 1926.1101 and 29 CFR 1910.1001.
OSHA has also issued interpretive letters that provide clarification about how materials containing less than 1%
asbestos should be handled. (see www.osha.gov)

Appendix A
Data Tables

Table 1
Asbestos-containing Materials by Homogeneous Area
White Mesa Mill-Denison Mines Corp
Warehouse-Maintenance Building
Homogeneous
Area Number Material Description/Location
Asbestos
Content AmountFriability
M004
12" x 12" Tan vinyl floor tile and black mastic
106A, 107C, 107D-Offices and 200-Lunch
Room
12-15%
>1-8%
2,140Category 1
Non-friable
Floor Tile and Mastic on Cement sq. ft.Chrysotile: tile
Chrysotile:
mastic
M004A
Black tar mastic
107A-Instrument Shop/Tool Room
8%420Category 1
Non-friable
The asbestos floor mastic is under non-asbestos floor tile and yellow adhesive.
Floor Tile Mastic Under Non-ACM sq. ft.Chrysotile
Asbestos Survey Report - Table 1 Warehouse-Maintenance BuildingPage 1 of 1
White Mesa Mill-Denison Mines Corp
Note: A homogeneous area of suspect material is considered an Asbestos-containing Material (ACM) if any one sample contains greater than 1% asbestos
Table 2
Homogeneous Areas That Do Not Contain Asbestos
White Mesa Mill-Denison Mines Corp
Warehouse-Maintenance Building
Material DescriptionHomogeneous
Area Number Material Description/Location Amount
M001
White joint compound, paper tape and
gypsum plaster
100-Corridor, 101 and 102-Men's Lockers,
103-Women's Lockers and 200-Lunch Room
3,200 sq. ft.Wall System
M002
Gray sheet vinyl flooring
100-Corridor, 101, 102, 103-Lockers and 105-
Laundry
1,170 sq. ft.Vinyl Floor Sheeting
M003
12" x 12" Pink vinyl floor tile
103-Women's Lockers
15 sq. ft.Floor Tile - Exposed
M005
12" x 12" Gray Vfinyl floor tile and yellow
adhesive
107A-Instrument Shop/Tool Room
420 sq. ft.
There is asbestos black floor mastic underneath.
Floor Tile - Exposed
M006
Tan mastic
107A-Instrument Shop/Tool Room
90 ln. ft.Cove Base Adhesive
M007
Brown mastic
106A, 107C and 107D-Offices
145 ln. ft.Cove Base Adhesive
M008
Off-white mastic
100-Corridor, 101, 102, 103-Lockers, and
105-Laundry
240 ln. ft.Cove Base Adhesive
Asbestos Survey Report - Table 2 Page 1 of 2 Warehouse-Maintenance Building
White Mesa Mill-Denison Mines Corp
Material DescriptionHomogeneous
Area Number Material Description/Location Amount
M009
Gray sealant
On ducts in 106-Warehouse and 107-
Maintenance
30 ln. ft.Duct Sealant
M010
White sink undercoat
107-Maintenance
1 unitSink Undercoat
S001
White textured-plaster wall
100-Corridor, 101 and 102-Men's Lockers,
103-Women's Lockers and 200-Lunch Room
3,200 sq. ft.Surfacing Material
Asbestos Survey Report - Table 2 Page 2 of 2 Warehouse-Maintenance Building
White Mesa Mill-Denison Mines Corp
Table 3
Bulk Sample Analytical Results by Sample Number
White Mesa Mill-Denison Mines Corp
Warehouse-Maintenance Building
Homogeneous
Area Number Material Sampled Analytical ResultsSample
Number Sample Location
A1081S-01 S001 100-Corridor NDSurfacing Material
A1081S-02 S001 102-Men's Locker Room NDSurfacing Material
A1081S-03 S001 103A-Women's Restroom NDSurfacing Material
A1081S-04 M001 101-Men's Lockers NDWall System
A1081S-05 M001 200-Lunch Room NDWall System
A1081S-06 M001 107A-Instrument Shop/Tool
Room
NDWall System
A1081S-07 M002 102-Men's Locker Room NDVinyl Floor Sheeting
A1081S-08 M002 100-Corridor NDVinyl Floor Sheeting
A1081S-09 M002 103-Women's Locker Room NDVinyl Floor Sheeting
A1081S-10 M003 103-Women's Locker Room NDFloor Tile - Exposed
A1081S-11 M004 200-Lunch Room 12%Chrysotile: tileFloor Tile and Mastic
on Cement
A1081S-12 M004 107D-Foreman's Maintenance
Office
15%
>1%
Chrysotile: tile
Chrysotile:
mastic
Floor Tile and Mastic
on Cement
A1081S-13 M004A 107D-Foreman's Maintenance
Office
8%ChrysotileFloor Tile Mastic
A1081S-14 M005 107A-Instrument Shop/Tool
Room
NDFloor Tile - Exposed
A1081S-15 M006 107A-Instrument Shop/Tool
Room
NDCove Base Adhesive
Asbestos Survey Report - Table 3 Page 1 of 2 Warehouse-Maintenance Building
White Mesa Mill-Denison Mines Corp
Homogeneous
Area Number Material Sampled Analytical ResultsSample
Number Sample Location
A1081S-16 M007 1107C-Electrical Foreman's
Office
NDCove Base Adhesive
A1081S-17 M008 102-Men's Locker Room NDCove Base Adhesive
A1081S-18 M009 106-Warehouse NDDuct Sealant
A1081S-19 M010 107-Maintenance NDSink Undercoat
Note: ND =No Asbestos Detected, NA= Not Analyzed, TR = <1% Asbestos, PC = Point Count
Asbestos Survey Report - Table 3 Page 2 of 2 Warehouse-Maintenance Building
White Mesa Mill-Denison Mines Corp
Table 4
Bulk Sample Analytical Results by Homogeneous Area Number
White Mesa Mill-Denison Mines Corp
Warehouse-Maintenance Building
Homogeneous
Area Number Material Sampled Analytical ResultsSample
Number Sample Location
A1081S-04 M001 101-Men's Lockers NDWall System
A1081S-05 M001 200-Lunch Room NDWall System
A1081S-06 M001 107A-Instrument Shop/Tool
Room
NDWall System
A1081S-07 M002 102-Men's Locker Room NDVinyl Floor Sheeting
A1081S-08 M002 100-Corridor NDVinyl Floor Sheeting
A1081S-09 M002 103-Women's Locker Room NDVinyl Floor Sheeting
A1081S-10 M003 103-Women's Locker Room NDFloor Tile - Exposed
A1081S-11 M004 200-Lunch Room 12%Chrysotile: tileFloor Tile and Mastic
on Cement
A1081S-12 M004 107D-Foreman's Maintenance
Office
15%
>1%
Chrysotile: tile
Chrysotile:
mastic
Floor Tile and Mastic
on Cement
A1081S-13 M004A 107D-Foreman's Maintenance
Office
8%ChrysotileFloor Tile Mastic
A1081S-14 M005 107A-Instrument Shop/Tool
Room
NDFloor Tile - Exposed
A1081S-15 M006 107A-Instrument Shop/Tool
Room
NDCove Base Adhesive
A1081S-16 M007 1107C-Electrical Foreman's
Office
NDCove Base Adhesive
A1081S-17 M008 102-Men's Locker Room NDCove Base Adhesive
A1081S-18 M009 106-Warehouse NDDuct Sealant
A1081S-19 M010 107-Maintenance NDSink Undercoat
A1081S-01 S001 100-Corridor NDSurfacing Material
A1081S-02 S001 102-Men's Locker Room NDSurfacing Material
Asbestos Survey Report - Table 4 Page 1 of 2 Warehouse-Maintenance Building
White Mesa Mill-Denison Mines Corp
Homogeneous
Area Number Material Sampled Analytical ResultsSample
Number Sample Location
A1081S-03 S001 103A-Women's Restroom NDSurfacing Material
Note: ND =No Asbestos Detected, NA= Not Analyzed, TR = <1% Asbestos, PC = Point Count
Asbestos Survey Report - Table 4 Page 2 of 2 Warehouse-Maintenance Building
White Mesa Mill-Denison Mines Corp
Table 5
Damage and Hazard Assessment by Homogeneous Area
White Mesa Mill-Denison Mines Corp
Warehouse-Maintenance Building
Homogeneous
Area Number DamageSubstrate AccessibilityMaterial
Type
Assessment
Category
Disturbance
Potential
M004 X No Damage Rarely AccessedCement LowFloor Tile and Mastic
on Cement
M004A X No Damage Rarely AccessedCement LowFloor Tile Mastic
Under Non-ACM
Coverings
Damage Categories
Each homogeneous area of ACM was classified into one of the following seven categories, as specified in
EPA’s AHERA regulations (40 CFR §763.88):
(1) Damaged or significantly damaged thermal system insulation ACM.
(2) Damaged friable surfacing ACM.
(3) Significantly damaged friable surfacing ACM.
(4) Damaged or significantly damaged friable miscellaneous ACM.
(5) ACBM with potential for damage.
(6) ACBM with potential for significant damage.
(7) Any remaining friable ACBM or friable suspected ACBM.
(X) Not applicable (material is non-friable surfacing or miscellaneous material).

The damage categories are defined as follows:
“Undamaged” means the material had no visible damage, or extremely minor damage or surface
marring (i.e., a room full of floor tile with only two or three small corners chipped off of the tile).
“Slight Damage” means the material had visible damage evenly distributed over less than 10% of its
surface, or localized over less than 25% of its surface.
“Significantly Damaged” means the material had visible damage that is evenly distributed over 10% or
more of its surface or localized over 25% or more of its surface.

Hazard Assessment Categories
Each homogeneous area of ACM was evaluated for accessibility and the hazard the material presents to
building occupants and the general public. The assessment assumes a fully occupied building.
“Inaccessible” means the material was located in an area that people had no reason to enter and could
not access without special measures. One example would be above a solid ceiling.
“Rarely-Accessed” identifies a material that was in a location that could be accessed but wasn't unless
there was a specific needed. An example would be a pipe tunnel. Another example would be a high
ceiling that is out of reach and not subject to any specific disturbances.
“Periodic Access” identifies a material that was in a location that was accessible, was not occupied full
time, but was accessed on a routine basis. An example would be a mechanical room or boiler room.
“Continuous Access” identifies a material that was in a location that was occupied full time and was
within reach of the occupants, or was frequently subject to direct disturbance. Examples would be
exposed floor tile or a normal height ceiling.
Asbestos Survey Report - Table 5 Page 1 of 1 Warehouse-Maintenance Building
White Mesa Mill-Denison Mines Corp
Table 6
Estimated Abatement Costs by Homogeneous Area
White Mesa Mill-Denison Mines Corp
Warehouse-Maintenance Building
Homogeneous
Area Number Material Extended
CostAmountUnit Cost
M004 Floor Tile and Mastic on Cement 2,140 sq. ft.$3.36 $7,190
M004A Floor Tile Mastic Under Non-AC 420 sq. ft.$3.36 $1,411
Total Estimated Abatement Cost $8,602
Note: Estimated abatement costs do not include replacement costs or costs for a consultant to manage the abatement.
Asbestos Survey Report - Table 6 Page 1 of 1 Warehouse-Maintenance Building
White Mesa Mill-Denison Mines Corp

Appendix B
Building Floor Plans

Men's Locker Room
102
Men's Restroom
102A
Shower
102B
Storage
102B
100 Closet
100A
Men's Locker Room
101
Laundry
105
Women's
Locker Room
103
Women's
Restroom
103A
Warehouse
106
107A
106B 107B
106A
107C
107D
Maintenance
107
Electrical
108
Carpenter
110
109 111A
Rubbering
111
2
18
717
1 8
4
10
3
9
20
6
15
14
19
16
12
13
Lunch Room
200
Storage
200B
Storage
200A
11 5
Second Floor
Sample Location & Number10
Room Name & Number
Explanation
101
Asbestos-containing Floor Tile & Mastic
Asbestos-containing Floor Mastic
PROJECT No:
SHEET:
DRAWN BY:
REVIEWED BY:
De
n
i
s
o
n

M
i
n
e
s

C
o
r
p
.
Wh
i
t
e

M
e
s
a

M
i
l
l
64
2
5

S
o
u
t
h

H
i
g
h
w
a
y

1
9
1
Bl
a
n
d
i
n
g
,
U
T
As
b
e
s
t
o
s

&

H
a
z
a
r
d
o
u
s

M
a
t
e
r
i
a
l
s

S
a
m
p
l
e

L
o
c
a
t
i
o
n

M
a
p
DATE:
DATE:
DATE:
REVISED BY:
640 E. Wilmington Ave.
Salt Lake City, UT 84106801.466.2223
[e-mail]
0 10'20'
12U-A1081
1 of 1
Keith
07-11-2012

V:\
-

1
2

P
r
o
j
e
c
t
s
\
1
2
U
-
A
1
0
8
1

D
e
n
i
s
o
n

M
i
l
l

S
i
t
e

A
s
b
e
s
t
o
s

I
n
s
p

&

M
P
\
D
r
a
w
i
n
g
s
\
1
2
U
A
1
0
8
1
.
d
w
g
,

w
a
r
e
h
o
u
s
e
,

7
/
1
2
/
2
0
1
2

1
1
:
2
0
:
3
1

A
M
,

k
e
i
t
h
f
,

A
N
S
I

f
u
l
l

b
l
e
e
d

B

(
1
7
.
0
0

x

1
1
.
0
0

I
n
c
h
e
s
)

Appendix C
Photographs

Photograph 1
The surfacing material and the wall system did not
contain asbestos.
Photograph 2
This gray vinyl sheet flooring did not contain
asbestos.

Photograph 3
The vinyl floor tile and black mastic contained >1-
15% chrysotile asbestos.
Photograph 4
The cove base adhesive used in the building did not
contain asbestos.

Photograph 5
The gray duct sealant was reported as none detected
for asbestos.
Photograph 6
This sink undercoat in the maintenance area did not
contain asbestos.

Appendix D
Laboratory Results

,.......----- -DIXON INFORMATION INC.--------,
MICROSCOPY,ASBESTOS ANALYSIS &CONSULTING
A.I.H.A.ACCREDITED LABORATORY #101579
NVLAP LAB CODE 101012-0
June 6,2012
Mr. Lono Folau
IHl Environ mental
640 East Wilmington Ave
Salt Lake City.UT 84106
Ref: Batch #104900,Lab #H19724 -H19743
Received June 6,2012
Test report.Page I of 5
Denison Mines
White Mesa Mill Shop
6425 S.Highway 191,Blanding,Utah
Sampled by Lono Folau, 5/30/20 12
Dear Mr. Folau:
Samples H19724 through 11 19743 have been analyzed by visual estimation based on EPA-
600 /M4-82-020 December 1982 optical microscopy test method ,with guidance from the
EPA/600/R-93/l 16 July 1993and OSHA ID 19 1methods.Appendix "A"containsstatements which
an accredited laboratory must make to meet the requirements of accrediting agencies.It also
contains additional information aboutthe method ofanalysis.Thisanalysis is accredited by NVLAP.
Appe ndix "A"must be included as an essential part ofthis test report.The data for this report is
accredited by NVLAP for laboratory number 101012-0.It does not con tain data or calibrations for
tests performed under the AIHA program under lab code 101579.
This report may be reproduced but all reproduction must be in full unless written approva l
is received from the laboratory for partial reproduction.TIle results ofanalysis are as follows:
Lab H 19724.Field A I081S-I Sur facing Material
This sample contains three types ofmaterial: The first type is white paint layers:the second type is
yellow mastic:the third type is off-white gypsum plaster with mica.This sample is non-
homogeneous.Asbestos is none de tected.
.The first type is 49%ofthe sample.The second type is 1%ofthe sample.The third type is 50%of
t'he sample.
'--+---- -78 WEST 2400 SOUTH ·SOUTH SALT LAKE ,UTAH 84115 -3013
PHONE [phone] · FAX [phone] ·RES.801-571-7695
Batch =104900
Lab =H19724 -HI 9743
Page:'of 5
Lab HI 9715.Field '\IOS1S-")Surfacing Material
Thi s sample contains three type s ofmat eria l:The first type is white paint layers:the second type is
off-white limestone plaster with mica: the third type is brown plant fiber paper. This sample is non-
hom ogeneous.Asbestos is none detected.
The first type is 40%of the sample.Th e second type is 59%of the samp le.The third type is I%of
the sample.
Lab H197")6 .Field A I081S-3 Surfacing Material
This sample contains three types of material:The first type is white paint:the second type is off-
white lime stone plaster:the third type is off-wh ite plant tiber paper.This sample is non-
hom ogeneous.Asbestos is none detected.
The first type is 5% of the sample. The second type is 92%of the sample .The third type is 3%of
the sample.
Lab H19727.f ield A1081S-4 Wall System
This sample contains four types of material: Th e first type is off-white gyps um plaster with mica:
the second type is 5%cross woven fiberglass in off-white limestone plaster with mica:the third type
is off-white and brown plant fiber paper layers:the fourth type is 1%plant tiber in wh ite gypsum
plaster.This sample is non-homogeneous.Asbestos is none detected.
The first type is 5%of the sample.The second type is 5%of the sample.The third type is 5%of
the sample.The fourt h type is 85%ofthe sample.
Lab H197! 8.Field '\108 I S-5 \\'all System
This sa mple contains off-white paint.white limestone plaster with .bro wn and off-wh ite plant tibe r
paper.and white gypsum plaster with 1%plant fiber.This sample is non-homogeneous.Asbestos
is none detected.
The paint is I%of the sample.The plaster with limestone is 9% of the sample"The pla nt tiber
paper is 5%ofthe sample.The white gypsum plaster is 85%of the sample.
Lab HI97!9.Field A I081S-6 Wall System
Thi s sample contains wh ite paint.white gypsum plaster with mica .brown and off-white plant fiber
paper.and wh ite gypsum plaster wit h 1%plan t fiber. Th is sample is non-homogeneou s"Asbestos
is no ne detected.
The paint is 1% of the sample.The plaste r with mica is 9% of the sample.The plant fiber paper is
5%of the sample.The white gypsum plaster is 85%ofthe sample.
Batch "104900
Lab #1-/1 9724 -H 19743
Page 3 of 5
Lab 1-/1 9730.Field A 1OS 1S-7 Vinvl Floor Sheeting
This sample contains two types ofmaterial:The first type is gray plastic :the second type is 35%
plant fiber.5%fiber glass and 5%synthetic fiber in gray bindcr. This sample is non-homogeneous.
Asbestos is none detected.
The first type is 60%of the sample.The seco nd type is 40%ofthc sample.
~ab 11 19731. Field Al 081S-8 Vinyl Floo r Sheeting
Th is sample contains two type s ofmaterial:The first type is off-white paint:the second type is gray
rubber and limestone.Thi s sample is non-homogene ous. Asbestos is none d etected.
Th e first type is 1%of the sample.The second type is 99%ofthe sample.
Lab H19737 .Field A l 081S-9 Vinyl Floor Sheeting
This sample contains two types of material:The first type is white paint:the seco nd type is gray
rubber and limestone.This sample is non-homogeneous.Asbestos is none detected .
The first type is I%of the sample. The second type is 99% of the sample.
Lab 1-1 19733.Field A I081S-10 Floor Tile
This is pink plastic and limestone tile with debris on the surface. Asbestos is no ne detected.
Lab H19 7'4.Field AI08 1S-l l Floor Tile
Thissample contains three types ofmaterial:The first type is 12%ebrysotile asbestos in tan plastic
and limestone tile:the second type is black tar mast ic:the third type is gray sandy plaster.Th is
sample is non-homogeneous.
The first type is 98%of thc sample. The second type is 1%ofthc sample.The third type is 1%of
the sample.
Lab 111 9735. Field A1081S-Il Floor Tile
This is 15%chrysotile asbestos in a tan plastic and limestone tile.
Note: The black tar mastic contains greater than 1%ch rysotile asbestos.
The tile is 99%ofthe sample.The black tar mast ic is 1%of thc sample.
Lab 1-/19736.Field A1081S-13 Floor Tile Mastic
This is 8%ch rys otile asb estos in black tar mas tic.
Batch"104900
Lab #HI9724 -HI 9743
Page 4 of5
Lab II 1973 7.Field .';'1 OS 1S-14 Floor Tile
This is a gray plastic and limestone tile with yellow resin mastic . Asbestos is none d etected.
The tile is 99%of the sample. Th e mastic is 1%of the sample.
Lab 11 IQ/38 .Field AI08 1S-15 Cove Base Adhesive (Tan)
This sample contains three types of material:The first type is tan mastic with limestone:the second
type is white paint:the third type is white limestone plaster with mica.This sample is non-
homogeneous.As bestos is none detected.
The first type is 94%of the sample. The second type is 1%of the sam ple.The third type is 5%of
the sample.
Lab 11 19739.Field A I081S-16 CO\'e Base Adhesive (Brown)
This sample contains two types of material:The first type is brown resin mastic:the second type is
white limestone plaster with mica.This sample is non-homogeneous.Asbestos is none detected .
The first type is 80%of the sample. The second type is 20% of the sample.
Lab 11 19740 .Field A 108IS-17 Cove Base Adhesive
This sample contains two types of material:The first type is tan mastic with limestone:the second
type is brown plant fiber paper. This sample is non-homogeneous.Asbestos is none detected.
The first type is 99%of the sample.The second type is 1%of the sample.
Lab H I974 1.Field A I081S-I8 Duct Sealant
This is gray sealant with limestone.Asbestos is no ne detected.
Lab HI 974".Field A1081S-19 Sink lindercoat
This is 5%organic fiber in white binder with limestone and mica.Asbes tos is none detected.
Batch s 104900
Lab s HI 9724 -H19743
Page 5 of 5
Lab H19743.Field AI081S-10 Surfacing Material
This sample contains three types of material: The first type is off-white paint:the second type is off-
white limestone plaster with mica:the third type isoff-white gypsum plaster with mica.This sampl e
is non-homogeneous.Asbestos is none detected.
The first type is 10%ofthe sample.The second type is 45% of the sample.The third type is 45%
of the sample.
In order to be sure reagents and tools used for analysis are not con taminated with asbestos.
blanks are tested.Asbestos was none detected in the blanks tested with this bulk sample set.
Very truly yours,
~.IJC
Steve H.o(on,President
~"
Dixon Information Inc.
78 West 2400 South
South Salt Lake,Utah 84115
Phone:[phone] Fax:[phone]
BULK ANALYTICAL REQUEST FORM
Turnaround Time -Circle One Batch Number IDlJ gOO
Rush (24 hours $25.00 per sample)
Non-rush (5 Working days $17.00 per sample)
/)el1;s.1?M/"es -p/,;,J-e M~.s....M ill.
Name oflocation sample was taken at::-:--=s:""h!..!o<-;e=--c--c-__-,-::-:----::-c-_-;-__---:::--_
Street address sample was taken at 6¥25"S:g,~hw"'tl/t)1 13/""",eI'nq ur
Sampled by:.I.0!?a h /<:lLL..'oJ
Description of Sample
Report to be sent to:L .,",0 Fa1",«-
Company:117'1 r"l1/ronmcnfaf
Address:c.ro.l!.N //m ln"-tk,,,we
City:$1,c.State:c/U T
Zip Code:¥'/IlJ ~
Telephone #:caDI)%6 -Z2Z3
Fax #:("01)i"·,"/~
E-mail:Il"o/~&iltl -e......CoM.
Lab #
12 V-A./oal _
Samples Collected
Date Time
Billingto be sent to:----:-_
Company:I HI L'n ",'ronn7~'lot.../
Address:-----:::-_
City:State:_
Zip Code:,-c-_
Telephone #:_
Fax #:_-;-::-:-;----:-:-::-::-:-_
PO #:_-'--_-'------"'-'_
Floot"tile
f:{ool a le.
Field #
A l oalS-
II
{'Z.
!3
Flo",..(de.
~V~bose:dlu:s.'ve..,(ra., )
Col''''-"'oS'"..d hes/....t!:.-('-raul,.,)
/1
S'nfc .H7det"c.o~-{-­
S'~y.f4.Co,;>!!,.,.,,,,,--f~;&d-
Chain ofCustody
Submission of asbestos samples for analysis and/or signing a chain of custody is the
equivalent of submission of a purchase order and constitutes an agreement to pay for services
provided at Dixon Informat~Inc::g'0rated standard schedule offees for services,
Submitted by:~-'.::Date:'I'-11 ~Time:_
Received b~':Q;;:;:;;;;Date:U ;;Time:\~'l..()
Received by Analyst:~-Date:t:.f 2 -/L Time:/bdJ
Returned by Lab:Date:Time: _
Appendix"A"
"This report relates only to the items tested. Thi s repo rt must not be used to claim
prod uct endorsement by NVLAP or A IHA ."
NV LA P and A IHA requires laboratories to state the conditio n of samples received for
testing: Th ese samples are in acceptable co ndition for analysis unless there is a statement
in the report of analysis that a test item has some character istics or condition that
precludes analysis or req uires a modification of standard analytica l methodology.II'a test
item is not acceptable,the reasons for non-acce ptability will be give n under the
lab oratory num ber for that particular test itcm.The reported percentages of each material
type are based on the sample recei ved by the laboratory and may not be representative of
the parent material.Or ientation of top and bottom may not be specified due to uncertainty
of orientation.
M ethods of Ana lysis and Limit of Detection
in a ir count analysis.the results may be biased when interferences arc noted.
The accuracy of asbestos analysis in bulk samples increases with increasing
concentration of asbestos.Pigment s.binders. small sample size.and multiple layers may
affect the analysis sensitivity.
There are two methods for ana lysis of as bestos in a bulk test sample. Visual
esti mation is the most sensitive method.If an analyst makes a patient sea rch. 0.1%or less
asbestos can be detected in a bulk sample.
The second method of analysis is a statistical approac h ca lled po int counting.EPA
will not acc ept visual estimations if a laboratory detects a trace of asbestos in a sample
i.e.anything less than I%asbesto s.Government age ncies regulate asbestos containing
materials (AC M) whenever the ACM is more than I%.OS HA require men ts apply on
samples co ntaining any amount of asbestos.
Due to the higher charge for a point count analysis,Dixon Information Inc.does not
perform a point count unless authorized to do so by the client.If a sample is po int
counted,when possible,various chemica l andlor physical means may be used to
concentrate the asbestos in the sample.This is permitted by the EPA method and it
increases the accuracy of the analysis.

Appendix E
Regulatory Factors

Several factors determine how asbestos in a building must be treated if it has the potential of
being disturbed during a renovation or demolition. These factors include the following:

Factor
EPA Regulations for
Asbestos Removal
OSHA Regulations for
Asbestos Removal
Definition of asbestos
in a building material
Defines ACM as a material
containing 1% or greater asbestos.
Defines an ACM as one containing
>1% asbestos.
Regulation of asbestos
in building materials
Regulates only ACM. If the asbestos
concentration in a material is shown
to be “none detected” by initial
analysis or 1% or less by point count
analysis, EPA/DAQ does not regulate
it.
Regulates not only ACM but all
materials containing any amount of
asbestos. Regulations are not as
stringent for materials containing
equal-to or less-than 1% asbestos but
greater than a “none detected”
concentration.
Determination of
asbestos concentration
in a gypsum board
wall system
Allows compositing of all layers
(joint compound, joint tape, and
gypsum board) into one sample,
which decreases the possibility that
the sample will be evaluated as an
ACM.
Requires that each layer of the wall
system be analyzed and reported
independently, which increases the
possibility of a sample containing
ACM or identifiable asbestos.
Defines regulated and
non-regulated ACM
Yes – Regulated ACM include friable
ACM and resilient flooring, asphalt
roofing, gaskets and packing that
have become friable and other ACM
that have a high probability of
becoming friable.
No – Requirements for asbestos work
procedures and worker training are
less stringent for resilient flooring,
asphalt roofing materials, and
materials containing greater than
“none detected” but not greater than
1% asbestos.
Notification of
asbestos abatement or
building demolition
required
Yes – Utah DAQ must be notified on
the appropriate form 10 working-days
prior to an asbestos abatement of
regulated asbestos material greater
than the NESHAP-established
notifiable quantity with demolition, or
demolition where abatement is not
required.
No – Not required.
Provision for allowing
ACM to remain in a
building during a
demolition.
Yes – Allows ACM resilient flooring,
asphalt roofing, and certain other non-
friable building materials in good
condition to remain in a building
during demolition as long as the
demolition process will not render
them friable.
No – If any asbestos is left in a
building during a demolition, the
demolition workers are expected to
meet the same OSHA requirements
that an abatement contractor would
meet if an abatement contractor was
conducting an abatement of those
materials.

Appendix F
Project Limitations

PROJECT LIMITATIONS
This Project was performed using, as a minimum, practices consistent with standards
acceptable within the industry at this time, and a level of diligence typically exercised by
EH&S consultants performing similar services.
The procedures used attempt to establish a balance between the competing goals of limiting
investigative and reporting costs and time, and reducing the uncertainty about unknown
conditions. Therefore, because the findings of this report were derived from the scope, costs,
time and other limitations, the conclusions should not be construed as a guarantee that all
universal, toxic and/or hazardous wastes have been identified and fully evaluated.
Furthermore, IHI assumes no responsibility for omissions or errors resulting from inaccurate
information, or data, provided by sources outside of IHI or from omissions or errors in public
records.
It is emphasized that the final decision on how much risk to accept always remains with the
client since IHI is not in a position to fully understand all of the client's needs. Clients with a
greater aversion to risk may want to take additional actions while others, with less aversion to
risk, may want to take no further action.

ATTACHMENT A.3

MAINTENANCE-WAREHOUSE FACILITY
ASBESTOS INSPECTION REPORT

IIHHII
E NVIRONMENTAL

ASBESTOS INSPECTION REPORT

Maintenance-Warehouse
White Mesa Mill-Denison Mines Corporation
6425 South Highway 191
Blanding, Utah

August 1, 2012

Prepared for:
Ms. Jo Ann Tischler, Corporate Director of Compliance & Permitting
Denison Mines
1050 17th Street, Suite 950
Denver, Colorado 80265

Prepared by: Reviewed by:

Lono Folau
Asbestos Inspector #ASB-0537
Jon H. Self
Asbestos Program Manager

IHI Project 12U-A1081
640 EAST WILMINGTON AVE SALT LAKE CITY UT 84106 TELEPHONE: [phone] FAX: [phone] E-MAIL: [e-mail]

SALT LAKE CITY SAN FRANCISCO PHOENIX DENVER SEATTLE

TABLE OF CONTENTS

EXECUTIVE SUMMARY .............................................................................................................. I 
1.0 INTRODUCTION ..............................................................................................................1 
2.0  BUILDING DESCRIPTION ................................................................................................1 
3.0 INSPECTION PROCEDURES ............................................................................................2 
3.1 Asbestos-Containing Material (ACM) ...............................................................2 
3.2 Bulk Sampling ...................................................................................................3 
3.3 Bulk Sample Analysis ........................................................................................3 
4.0 INSPECTION RESULTS ....................................................................................................4 
4.1 Asbestos-Containing Materials ..........................................................................4 
4.2 Non-Asbestos-Containing Materials ..................................................................4 
4.3 Bulk Sample Analytical Results ........................................................................5 
4.4 Damage and Hazard Assessment .......................................................................5 
4.5 Materials Requiring Special Considerations ......................................................5 
4.6 Assumed Asbestos-Containing Materials ..........................................................5 
4.7 Inaccessible Areas ..............................................................................................5 
4.8 Materials Assumed >1% Asbestos (no NESHAP point count) .........................6 
5.0 RESPONSE ACTIONS ......................................................................................................6 
5.1 Applicable Rules and Regulations .....................................................................6 
5.2  Renovation and Demolition (EPA and OSHA) .................................................6 
6.0 COST ESTIMATES ..........................................................................................................7 

APPENDICES

Appendix A: Data Tables
Appendix B: Building Floor Plans
Appendix C: Photographs
Appendix D: Laboratory Results
Appendix E: Asbestos Regulatory Factors
Appendix F: Project Limitations

Maintenance-Warehouse-White Mesa Mill TOC - 1 IHI Environmental
Denison Mines Asbestos Inspection Project No. 12U-A1081

EXECUTIVE SUMMARY
On May 31, 2012, IHI Environmental conducted an asbestos inspection of the Maintenance-
Warehouse facility of the White Mesa Mill, Denison Mines, located in Blanding, Utah. Ms.
Jo Ann Tischler, Corporate Director of Compliance and Permitting for Denison Mines,
requested this inspection to identify asbestos-containing materials (ACM) that exist in the
building.
ACM – IHI identified the following materials:
• Vinyl floor tile and mastic (2,140 square feet)
• Floor tile mastic (420 square feet)
Conclusions
Asbestos – IHI recommends that a Utah-certified asbestos abatement contractor remove and
properly dispose of all the ACM in this building that may be disturbed during remodel or
demolition.
Cost Estimates
IHI’s cost estimates for a Utah-certified asbestos abatement contractor to remove the ACMs
outlined above are approximately $8,600. The estimated cost does not include travel
expenses for an abatement contractor. These estimates do not include the costs for asbestos
abatement design and management consulting services.
The report that follows this Executive Summary should be read in its entirety because it
includes important information, such as material descriptions and locations, regulatory
requirements, and building-specific recommended response actions.
Maintenance-Warehouse-White Mesa Mill i IHI Environmental
Denison Mines Asbestos Inspection Project No. 12U-A1081
Executive Summary
Asbestos-containing Materials by Homogeneous Area
White Mesa Mill-Denison Mines Corp
Warehouse-Maintenance Building
Homogeneous
Area Number Material Description/Location Asbestos
Content Amount Cost
Estimate(1)
M004 12-15%
>1-8%
2,140 sq. ft.Chrysotile:
tile
Chrysotile:
mastic106A, 107C, 107D-Offices and 200-Lunch
Room
Floor Tile and Mastic on Cement - 12" x
12" Tan vinyl floor tile and black mastic
$7,190
M004A 8%420 sq. ft.Chrysotile
107A-Instrument Shop/Tool Room
Floor Tile Mastic Under Non-ACM
Coverings - Black tar mastic
$1,411
Cost Estimates include asbestos removal costs only; abatement design, management fees and
replacement costs are not included. Please refer to Section 6.0 for more details.
Note 1:
Executive Summary Table Warehouse-Maintenance Building
White Mesa Mill-Denison Mines Corp
Page 1 of 1

ASBESTOS INSPECTION

Maintenance-Warehouse
White Mesa Mill-Denison Mines Corp
6425 South Highway 191
Blanding, Utah 84511

1.0 INTRODUCTION
On May 31, 2012, IHI Environmental conducted an asbestos inspection of the Maintenance-
Warehouse located at 6425 South Highway 191 in Blanding, Utah. Ms. Jo Ann Tischler, of
Denison Mines, requested this inspection to identify asbestos-containing materials (ACM)
that exist in the facility.
2.0 BUILDING DESCRIPTION
• Building Identification
Building Name .............................Maintenance-Warehouse (Shop)
Building Address ........................6425 South Highway 191, Blanding, Utah 84511
• Building Construction
Building Construction Date .........1978
Renovations..................................Not known
Building Type .............................Shop, warehouse, lockers, offices, and lunch
room
Building Total Sq. Ft....................19,800 square feet
Structural System ........................Concrete foundation with sheet metal
Exterior Wall Construction .........Sheet metal
Floor Deck Construction .............Concrete
Roof Deck Construction .............Metal
Roof Construction .......................Metal
• Floors
Floors Above Grade .................... Two (Lunch room)
Floors Below Grade .................... None
• Interior Finishes
Floors ...........................................Vinyl floor tile, ceramic tile and concrete
Maintenance-Warehouse-White Mesa Mill 1 IHI Environmental
Denison Mines Asbestos Inspection Project No. 12U-A1081

Walls ............................................ Wall system and metal
Ceilings ........................................ Metal
Attic ............................................. None
Basement ..................................... None
• Building Mechanical
Heating Plant ............................... Not known
Main Heating Distribution: .......... Forced air
Cooling Plant ............................... Not known
Main A/C Distribution ................. Forced air

3.0 INSPECTION PROCEDURES
3.1 Asbestos-Containing Material (ACM)
IHI visually inspected all accessible areas of the building to identify suspect ACM. To assess
the condition and determine friability of the suspect materials, IHI visually examined and
touched all accessible surfaces, structures, and mechanical systems within the building.
Suspect ACM was identified and assessed by homogeneous areas. A homogeneous area is
defined as a single material, uniform in texture and appearance, installed at one time, and
unlikely to consist of more than one type, or formulation, of material. In cases where joint
compound and/or tape has been applied to wallboard (gypsum board) and cannot be visually
distinguished from the wallboard, it is considered an integral part of the wallboard and in
effect becomes one material forming a wall or ceiling “system."
Each homogeneous area was given a unique material identification (ID) number. Each ID
number begins with a letter: "S" for surfacing materials, "T" for thermal system insulation, or
"M" for miscellaneous materials. This letter is followed by a three-digit number, assigned in
consecutive order. This number is used to identify that specific homogeneous area
throughout the inspection report.
Maintenance-Warehouse-White Mesa Mill 2 IHI Environmental
Denison Mines Asbestos Inspection Project No. 12U-A1081

Maintenance-Warehouse-White Mesa Mill 3 IHI Environmental
Denison Mines Asbestos Inspection Project No. 12U-A1081
3.2 Bulk Sampling
To determine the asbestos content of materials, IHI collected bulk samples from all
accessible homogeneous areas of suspect ACM and submitted the samples to an accredited
laboratory for analysis.
The number of samples collected from each homogeneous area generally followed the U. S.
Environmental Protection Agency (EPA) Asbestos Hazard Emergency Response Act
(AHERA) regulations (40 CFR §763.86). Friable surfacing materials were sampled using the
random sampling scheme given in the EPA publication 560/5-85-030a, titled "Asbestos in
Buildings: Simplified Sampling Scheme for Friable Surfacing Materials." Bulk sample IDs
collected during the inspection were entered on chain-of-custody forms for submittal to the
analytical laboratory.
3.3 Bulk Sample Analysis
Bulk samples were analyzed using polarized light microscopy (PLM) and visual estimation
according to the EPA Interim Method for the Determination of Asbestos in Bulk Insulation
Samples, EPA-600/M4-82-020. Samples were analyzed by Dixon Information Inc. in Salt
Lake City, Utah. Dixon Information is accredited under the National Institute of Standards
and Technology, National Voluntary Laboratory Accreditation Program (NIST-NVLAP) for
bulk asbestos sample analysis, and is also accredited by the American Industrial Hygiene
Association (AIHA).
EPA’s National Emissions Standards for Hazardous Air Pollutants (NESHAP) and AHERA
regulations define ACM as material containing greater than 1% asbestos by weight; materials
containing 1% or less asbestos are not considered regulated ACM by the EPA. Further, the
NESHAP regulations state that any sample found to contain less than 10% asbestos but
greater than “none detected," by the visual estimation method used during PLM analysis,
must be assumed to contain greater than 1% asbestos unless confirmed by NESHAP point
counting analysis.1
Despite EPA (and Utah Division of Air Quality) rules exempting building materials
containing 1% or less asbestos from stringent regulation, Occupational Safety and Health

1 NESHAP point counting includes examining materials under a polarizing microscope using an eyepiece
reticule that superimposes a grid of points over the field of view. 400 points are examined.

Maintenance-Warehouse-White Mesa Mill 4 IHI Environmental
Denison Mines Asbestos Inspection Project No. 12U-A1081
Administration (OSHA) regulations outline specific precautionary work practices when
employees work with materials containing even trace amounts of asbestos.2
The laboratory reports can be found in Appendix D of this report.
4.0 INSPECTION RESULTS
4.1 Asbestos-Containing Materials
The Executive Summary and Table 1 in Appendix A list all homogeneous areas that contain
asbestos. Each material is described by type of material, friability and visual appearance.
Friability is defined in accordance with EPA’s NESHAP regulations.
• “Friable ACM” is any material containing more than 1% asbestos (as determined by
PLM) that, when dry, may be crumbled, pulverized, or reduced to powder by hand
pressure and also includes non-friable ACM that may become friable during building
demolition.
• “Non-friable ACM” is any material containing more than 1% asbestos (as determined
by PLM) that, when dry, cannot be crumbled, pulverized, or reduced to powder by
hand pressure.
• “Category I non-friable ACM” are asbestos-containing resilient floor coverings
(commonly known as vinyl asbestos tile (VAT)), asphalt roofing products, packings,
and gaskets.
• “Category II non-friable ACM” encompasses all other non-friable ACM.
• “Non-friable RACM” is used to denote thermal system insulation that is in good
condition but would become friable during renovation or demolition and therefore is
"regulated asbestos containing material" (RACM).
4.2 Non-Asbestos-Containing Materials
Homogeneous areas of suspect ACM are identified as non-ACM if material contains no
detectable asbestos. Table 2, located in Appendix A of this report, lists all homogeneous
areas that were found to be non-ACM.

2 OSHA regulations pertaining to asbestos in buildings include 29 CFR 1926.1101 and 29 CFR 1910.1001.
OSHA has also issued interpretive letters that provide clarification about how materials containing less than 1%
asbestos should be handled. (see www.osha.gov)

4.3 Bulk Sample Analytical Results
Table 3, located in Appendix A of this report, lists all the bulk samples (chronologically by
sample number) collected from homogeneous areas of suspect ACM, and the laboratory
analytical results. Each sample was given a unique sample number. There may be more than
one sample number for the same homogeneous area of suspect ACM indicating multiple
samples were collected from that homogeneous material. The homogeneous areas of suspect
ACM are identified on this table by their material identification numbers. The sample
location listed on this table provides a brief, but specific, description of the location where
the sample was collected. This is different from the homogeneous area location provided on
Tables 1 and 2. Table 4 is the same as Table 3, except that the entries have been sorted by
homogeneous area number.
4.4 Damage and Hazard Assessment
Each homogeneous area of ACM was assessed for existing damage, accessibility, and
potential for future damage, this information is presented in Table 5, located in Appendix A
of this report. This table also lists the substrate beneath each homogeneous area of ACM.
Damage and hazard assessment categories are included in the tables in Appendix A.
4.5 Materials Requiring Special Considerations
None
4.6 Assumed Asbestos-Containing Materials
None
4.7 Inaccessible Areas
Suspect materials that were hidden or inaccessible may not have been characterized by this
inspection. Therefore, any material not identified in this report as having been tested should
be treated as suspect ACM until it has been sampled by a Utah-certified inspector and
analyzed by an accredited laboratory applying EPA methods.
In addition, some building structures may have been constructed after the application of
ACM, and therefore may have obscured these materials from visual examination during this
inspection. Typical scenarios include thermal system insulation inside hardened mechanical
Maintenance-Warehouse-White Mesa Mill 5 IHI Environmental
Denison Mines Asbestos Inspection Project No. 12U-A1081

Maintenance-Warehouse-White Mesa Mill 6 IHI Environmental
Denison Mines Asbestos Inspection Project No. 12U-A1081
chases, floor tile and mastic under walls, and sprayed-on texturing and fireproofing behind
structural supports or architectural features.
4.8 Materials Assumed >1% Asbestos (no NESHAP point count)
None
5.0 RESPONSE ACTIONS
5.1 Applicable Rules and Regulations
In Utah, EPA asbestos regulations are administered by the Utah Division of Air Quality
(DAQ).3 The Utah Occupational Safety and Health Administration (UOSH) has adopted the
Federal OSHA regulations.4 In addition, the Salt Lake Valley Health Department (SLVHD)
regulates demolition activities in Salt Lake County.5 The SLVHD regulations for pre-
demolition building inspections require an asbestos inspection, but also require building
owners to inspect the building for other hazardous materials such as universal wastes,
hazardous and toxic wastes, and lead-based paint. Like asbestos, these wastes, if present,
must be removed prior to building demolition.
Regulatory factors relevant to asbestos abatement decision-making are included in Appendix E.
5.2 Renovation and Demolition (EPA and OSHA)
A listing of ACM found during this inspection is presented in the Executive Summary at the
front of this report, and in Appendix A, Table 1.
NESHAP regulations require the removal of friable ACM and non-friable ACM that could
become friable during demolition or renovation activities. Therefore, we recommend that all
of the ACM in this building be removed and properly disposed of by a licensed asbestos
abatement contractor if total demolition of the facility is planned, or those materials that will
be impacted by renovation plans be removed prior to the commencement of renovation work.
Despite EPA (and Utah Division of Air Quality) rules exempting building materials

3 R307-801. Asbestos, Utah Division of Air Quality Rules, Implementation of Toxic Substances Control Act
Title II, Asbestos Certification, Asbestos Training, notifications and Asbestos Work Practices for Renovations
and Demolitions (See www.airquality.utah.gov). 4 Asbestos, Tremolite, Anthophyllite, and Actinolite Standards, Chapter D (Construction), Section 58; and
Chapter Z (General Industry), Section 1001, Utah Occupational Safety and Health Rules and Regulations
(Administered by Utah Occupational Safety and Health Division) (See www.uosh.utah.gov). 5 Salt Lake City – County Health Department, Health Regulation #1 Section 12 (See www.slvhealth.org).

Maintenance-Warehouse-White Mesa Mill 7 IHI Environmental
Denison Mines Asbestos Inspection Project No. 12U-A1081

containing 1% or less asbestos from stringent regulation, Occupational Safety and Health
Administration (OSHA) regulations outline specific precautionary work practices when
employees work with materials containing even trace amounts of asbestos.6 Strict
compliance by building owners with the OSHA asbestos regulations may result in response
actions not required by the EPA and Utah DAQ for certain unregulated materials.
6.0 COST ESTIMATES
Details of the estimated removal costs by homogeneous area can be found in Table 6,
Appendix A, and in the Executive Summary table. These estimates are provided for
budgeting and planning only, and do not have a level of accuracy sufficient to be used as a
construction design cost estimate. The actual cost of asbestos removal is dependent on
factors such as the size of the job, the required time frame for removal, the time of year the
job is conducted, and economic factors. These estimates do not include replacement costs, or
the cost for asbestos abatement design and management consulting services.

6 OSHA regulations pertaining to asbestos in buildings include 29 CFR 1926.1101 and 29 CFR 1910.1001.
OSHA has also issued interpretive letters that provide clarification about how materials containing less than 1%
asbestos should be handled. (see www.osha.gov)

Appendix A
Data Tables

Table 1
Asbestos-containing Materials by Homogeneous Area
White Mesa Mill-Denison Mines Corp
Warehouse-Maintenance Building
Homogeneous
Area Number Material Description/Location
Asbestos
Content AmountFriability
M004
12" x 12" Tan vinyl floor tile and black mastic
106A, 107C, 107D-Offices and 200-Lunch
Room
12-15%
>1-8%
2,140Category 1
Non-friable
Floor Tile and Mastic on Cement sq. ft.Chrysotile: tile
Chrysotile:
mastic
M004A
Black tar mastic
107A-Instrument Shop/Tool Room
8%420Category 1
Non-friable
The asbestos floor mastic is under non-asbestos floor tile and yellow adhesive.
Floor Tile Mastic Under Non-ACM sq. ft.Chrysotile
Asbestos Survey Report - Table 1 Warehouse-Maintenance BuildingPage 1 of 1
White Mesa Mill-Denison Mines Corp
Note: A homogeneous area of suspect material is considered an Asbestos-containing Material (ACM) if any one sample contains greater than 1% asbestos
Table 2
Homogeneous Areas That Do Not Contain Asbestos
White Mesa Mill-Denison Mines Corp
Warehouse-Maintenance Building
Material DescriptionHomogeneous
Area Number Material Description/Location Amount
M001
White joint compound, paper tape and
gypsum plaster
100-Corridor, 101 and 102-Men's Lockers,
103-Women's Lockers and 200-Lunch Room
3,200 sq. ft.Wall System
M002
Gray sheet vinyl flooring
100-Corridor, 101, 102, 103-Lockers and 105-
Laundry
1,170 sq. ft.Vinyl Floor Sheeting
M003
12" x 12" Pink vinyl floor tile
103-Women's Lockers
15 sq. ft.Floor Tile - Exposed
M005
12" x 12" Gray Vfinyl floor tile and yellow
adhesive
107A-Instrument Shop/Tool Room
420 sq. ft.
There is asbestos black floor mastic underneath.
Floor Tile - Exposed
M006
Tan mastic
107A-Instrument Shop/Tool Room
90 ln. ft.Cove Base Adhesive
M007
Brown mastic
106A, 107C and 107D-Offices
145 ln. ft.Cove Base Adhesive
M008
Off-white mastic
100-Corridor, 101, 102, 103-Lockers, and
105-Laundry
240 ln. ft.Cove Base Adhesive
Asbestos Survey Report - Table 2 Page 1 of 2 Warehouse-Maintenance Building
White Mesa Mill-Denison Mines Corp
Material DescriptionHomogeneous
Area Number Material Description/Location Amount
M009
Gray sealant
On ducts in 106-Warehouse and 107-
Maintenance
30 ln. ft.Duct Sealant
M010
White sink undercoat
107-Maintenance
1 unitSink Undercoat
S001
White textured-plaster wall
100-Corridor, 101 and 102-Men's Lockers,
103-Women's Lockers and 200-Lunch Room
3,200 sq. ft.Surfacing Material
Asbestos Survey Report - Table 2 Page 2 of 2 Warehouse-Maintenance Building
White Mesa Mill-Denison Mines Corp
Table 3
Bulk Sample Analytical Results by Sample Number
White Mesa Mill-Denison Mines Corp
Warehouse-Maintenance Building
Homogeneous
Area Number Material Sampled Analytical ResultsSample
Number Sample Location
A1081S-01 S001 100-Corridor NDSurfacing Material
A1081S-02 S001 102-Men's Locker Room NDSurfacing Material
A1081S-03 S001 103A-Women's Restroom NDSurfacing Material
A1081S-04 M001 101-Men's Lockers NDWall System
A1081S-05 M001 200-Lunch Room NDWall System
A1081S-06 M001 107A-Instrument Shop/Tool
Room
NDWall System
A1081S-07 M002 102-Men's Locker Room NDVinyl Floor Sheeting
A1081S-08 M002 100-Corridor NDVinyl Floor Sheeting
A1081S-09 M002 103-Women's Locker Room NDVinyl Floor Sheeting
A1081S-10 M003 103-Women's Locker Room NDFloor Tile - Exposed
A1081S-11 M004 200-Lunch Room 12%Chrysotile: tileFloor Tile and Mastic
on Cement
A1081S-12 M004 107D-Foreman's Maintenance
Office
15%
>1%
Chrysotile: tile
Chrysotile:
mastic
Floor Tile and Mastic
on Cement
A1081S-13 M004A 107D-Foreman's Maintenance
Office
8%ChrysotileFloor Tile Mastic
A1081S-14 M005 107A-Instrument Shop/Tool
Room
NDFloor Tile - Exposed
A1081S-15 M006 107A-Instrument Shop/Tool
Room
NDCove Base Adhesive
Asbestos Survey Report - Table 3 Page 1 of 2 Warehouse-Maintenance Building
White Mesa Mill-Denison Mines Corp
Homogeneous
Area Number Material Sampled Analytical ResultsSample
Number Sample Location
A1081S-16 M007 1107C-Electrical Foreman's
Office
NDCove Base Adhesive
A1081S-17 M008 102-Men's Locker Room NDCove Base Adhesive
A1081S-18 M009 106-Warehouse NDDuct Sealant
A1081S-19 M010 107-Maintenance NDSink Undercoat
Note: ND =No Asbestos Detected, NA= Not Analyzed, TR = <1% Asbestos, PC = Point Count
Asbestos Survey Report - Table 3 Page 2 of 2 Warehouse-Maintenance Building
White Mesa Mill-Denison Mines Corp
Table 4
Bulk Sample Analytical Results by Homogeneous Area Number
White Mesa Mill-Denison Mines Corp
Warehouse-Maintenance Building
Homogeneous
Area Number Material Sampled Analytical ResultsSample
Number Sample Location
A1081S-04 M001 101-Men's Lockers NDWall System
A1081S-05 M001 200-Lunch Room NDWall System
A1081S-06 M001 107A-Instrument Shop/Tool
Room
NDWall System
A1081S-07 M002 102-Men's Locker Room NDVinyl Floor Sheeting
A1081S-08 M002 100-Corridor NDVinyl Floor Sheeting
A1081S-09 M002 103-Women's Locker Room NDVinyl Floor Sheeting
A1081S-10 M003 103-Women's Locker Room NDFloor Tile - Exposed
A1081S-11 M004 200-Lunch Room 12%Chrysotile: tileFloor Tile and Mastic
on Cement
A1081S-12 M004 107D-Foreman's Maintenance
Office
15%
>1%
Chrysotile: tile
Chrysotile:
mastic
Floor Tile and Mastic
on Cement
A1081S-13 M004A 107D-Foreman's Maintenance
Office
8%ChrysotileFloor Tile Mastic
A1081S-14 M005 107A-Instrument Shop/Tool
Room
NDFloor Tile - Exposed
A1081S-15 M006 107A-Instrument Shop/Tool
Room
NDCove Base Adhesive
A1081S-16 M007 1107C-Electrical Foreman's
Office
NDCove Base Adhesive
A1081S-17 M008 102-Men's Locker Room NDCove Base Adhesive
A1081S-18 M009 106-Warehouse NDDuct Sealant
A1081S-19 M010 107-Maintenance NDSink Undercoat
A1081S-01 S001 100-Corridor NDSurfacing Material
A1081S-02 S001 102-Men's Locker Room NDSurfacing Material
Asbestos Survey Report - Table 4 Page 1 of 2 Warehouse-Maintenance Building
White Mesa Mill-Denison Mines Corp
Homogeneous
Area Number Material Sampled Analytical ResultsSample
Number Sample Location
A1081S-03 S001 103A-Women's Restroom NDSurfacing Material
Note: ND =No Asbestos Detected, NA= Not Analyzed, TR = <1% Asbestos, PC = Point Count
Asbestos Survey Report - Table 4 Page 2 of 2 Warehouse-Maintenance Building
White Mesa Mill-Denison Mines Corp
Table 5
Damage and Hazard Assessment by Homogeneous Area
White Mesa Mill-Denison Mines Corp
Warehouse-Maintenance Building
Homogeneous
Area Number DamageSubstrate AccessibilityMaterial
Type
Assessment
Category
Disturbance
Potential
M004 X No Damage Rarely AccessedCement LowFloor Tile and Mastic
on Cement
M004A X No Damage Rarely AccessedCement LowFloor Tile Mastic
Under Non-ACM
Coverings
Damage Categories
Each homogeneous area of ACM was classified into one of the following seven categories, as specified in
EPA’s AHERA regulations (40 CFR §763.88):
(1) Damaged or significantly damaged thermal system insulation ACM.
(2) Damaged friable surfacing ACM.
(3) Significantly damaged friable surfacing ACM.
(4) Damaged or significantly damaged friable miscellaneous ACM.
(5) ACBM with potential for damage.
(6) ACBM with potential for significant damage.
(7) Any remaining friable ACBM or friable suspected ACBM.
(X) Not applicable (material is non-friable surfacing or miscellaneous material).

The damage categories are defined as follows:
“Undamaged” means the material had no visible damage, or extremely minor damage or surface
marring (i.e., a room full of floor tile with only two or three small corners chipped off of the tile).
“Slight Damage” means the material had visible damage evenly distributed over less than 10% of its
surface, or localized over less than 25% of its surface.
“Significantly Damaged” means the material had visible damage that is evenly distributed over 10% or
more of its surface or localized over 25% or more of its surface.

Hazard Assessment Categories
Each homogeneous area of ACM was evaluated for accessibility and the hazard the material presents to
building occupants and the general public. The assessment assumes a fully occupied building.
“Inaccessible” means the material was located in an area that people had no reason to enter and could
not access without special measures. One example would be above a solid ceiling.
“Rarely-Accessed” identifies a material that was in a location that could be accessed but wasn't unless
there was a specific needed. An example would be a pipe tunnel. Another example would be a high
ceiling that is out of reach and not subject to any specific disturbances.
“Periodic Access” identifies a material that was in a location that was accessible, was not occupied full
time, but was accessed on a routine basis. An example would be a mechanical room or boiler room.
“Continuous Access” identifies a material that was in a location that was occupied full time and was
within reach of the occupants, or was frequently subject to direct disturbance. Examples would be
exposed floor tile or a normal height ceiling.
Asbestos Survey Report - Table 5 Page 1 of 1 Warehouse-Maintenance Building
White Mesa Mill-Denison Mines Corp
Table 6
Estimated Abatement Costs by Homogeneous Area
White Mesa Mill-Denison Mines Corp
Warehouse-Maintenance Building
Homogeneous
Area Number Material Extended
CostAmountUnit Cost
M004 Floor Tile and Mastic on Cement 2,140 sq. ft.$3.36 $7,190
M004A Floor Tile Mastic Under Non-AC 420 sq. ft.$3.36 $1,411
Total Estimated Abatement Cost $8,602
Note: Estimated abatement costs do not include replacement costs or costs for a consultant to manage the abatement.
Asbestos Survey Report - Table 6 Page 1 of 1 Warehouse-Maintenance Building
White Mesa Mill-Denison Mines Corp

Appendix B
Building Floor Plans

Men's Locker Room
102
Men's Restroom
102A
Shower
102B
Storage
102B
100 Closet
100A
Men's Locker Room
101
Laundry
105
Women's
Locker Room
103
Women's
Restroom
103A
Warehouse
106
107A
106B 107B
106A
107C
107D
Maintenance
107
Electrical
108
Carpenter
110
109 111A
Rubbering
111
2
18
717
1 8
4
10
3
9
20
6
15
14
19
16
12
13
Lunch Room
200
Storage
200B
Storage
200A
11 5
Second Floor
Sample Location & Number10
Room Name & Number
Explanation
101
Asbestos-containing Floor Tile & Mastic
Asbestos-containing Floor Mastic
PROJECT No:
SHEET:
DRAWN BY:
REVIEWED BY:
De
n
i
s
o
n

M
i
n
e
s

C
o
r
p
.
Wh
i
t
e

M
e
s
a

M
i
l
l
64
2
5

S
o
u
t
h

H
i
g
h
w
a
y

1
9
1
Bl
a
n
d
i
n
g
,
U
T
As
b
e
s
t
o
s

&

H
a
z
a
r
d
o
u
s

M
a
t
e
r
i
a
l
s

S
a
m
p
l
e

L
o
c
a
t
i
o
n

M
a
p
DATE:
DATE:
DATE:
REVISED BY:
640 E. Wilmington Ave.
Salt Lake City, UT 84106801.466.2223
[e-mail]
0 10'20'
12U-A1081
1 of 1
Keith
07-11-2012

V:\
-

1
2

P
r
o
j
e
c
t
s
\
1
2
U
-
A
1
0
8
1

D
e
n
i
s
o
n

M
i
l
l

S
i
t
e

A
s
b
e
s
t
o
s

I
n
s
p

&

M
P
\
D
r
a
w
i
n
g
s
\
1
2
U
A
1
0
8
1
.
d
w
g
,

w
a
r
e
h
o
u
s
e
,

7
/
1
2
/
2
0
1
2

1
1
:
2
0
:
3
1

A
M
,

k
e
i
t
h
f
,

A
N
S
I

f
u
l
l

b
l
e
e
d

B

(
1
7
.
0
0

x

1
1
.
0
0

I
n
c
h
e
s
)

Appendix C
Photographs

Photograph 1
The surfacing material and the wall system did not
contain asbestos.
Photograph 2
This gray vinyl sheet flooring did not contain
asbestos.

Photograph 3
The vinyl floor tile and black mastic contained >1-
15% chrysotile asbestos.
Photograph 4
The cove base adhesive used in the building did not
contain asbestos.

Photograph 5
The gray duct sealant was reported as none detected
for asbestos.
Photograph 6
This sink undercoat in the maintenance area did not
contain asbestos.

Appendix D
Laboratory Results

,.......----- -DIXON INFORMATION INC.--------,
MICROSCOPY,ASBESTOS ANALYSIS &CONSULTING
A.I.H.A.ACCREDITED LABORATORY #101579
NVLAP LAB CODE 101012-0
June 6,2012
Mr. Lono Folau
IHl Environ mental
640 East Wilmington Ave
Salt Lake City.UT 84106
Ref: Batch #104900,Lab #H19724 -H19743
Received June 6,2012
Test report.Page I of 5
Denison Mines
White Mesa Mill Shop
6425 S.Highway 191,Blanding,Utah
Sampled by Lono Folau, 5/30/20 12
Dear 1"1r.Folau:
Samples H19724 through 11 19743 have been analyzed by visual estimation based on EPA-
600 /M4-82-020 December 1982 optical microscopy test method ,with guidance from the
EPA/600/R-93/l 16 July 1993and OSHA ID 19 1methods.Appendix "A"containsstatements which
an accredited laboratory must make to meet the requirements of accrediting agencies.It also
contains additional information aboutthe method ofanalysis.Thisanalysis is accredited by NVLAP.
Appe ndix "A"must be included as an essential part ofthis test report.The data for this report is
accredited by NVLAP for laboratory number 101012-0.It does not con tain data or calibrations for
tests performed under the AIHA program under lab code 101579.
This report may be reproduced but all reproduction must be in full unless written approva l
is received from the laboratory for partial reproduction.TIle results ofanalysis are as follows:
Lab H 19724.Field A I081S-I Sur facing Material
This sample contains three types ofmaterial: The first type is white paint layers:the second type is
yellow mastic:the third type is off-white gypsum plaster with mica.This sample is non-
homogeneous.Asbestos is none de tected.
.The first type is 49%ofthe sample.The second type is 1%ofthe sample.The third type is 50%of
t'he sample.
'--+---- -78 WEST 2400 SOUTH ·SOUTH SALT LAKE ,UTAH 84115 -3013
PHONE [phone] · FAX [phone] ·RES.801-571-7695
Batch =104900
Lab =H19724 -HI 9743
Page:'of 5
Lab HI 9715.Field '\IOS1S-")Surfacing Material
Thi s sample contains three type s ofmat eria l:The first type is white paint layers:the second type is
off-white limestone plaster with mica: the third type is brown plant fiber paper. This sample is non-
hom ogeneous.Asbestos is none detected.
The first type is 40%of the sample.Th e second type is 59%of the samp le.The third type is I%of
the sample.
Lab H197")6 .Field A I081S-3 Surfacing Material
This sample contains three types of material:The first type is white paint:the second type is off-
white lime stone plaster:the third type is off-wh ite plant tiber paper.This sample is non-
hom ogeneous.Asbestos is none detected.
The first type is 5% of the sample. The second type is 92%of the sample .The third type is 3%of
the sample.
Lab H19727.f ield A1081S-4 Wall System
This sample contains four types of material: Th e first type is off-white gyps um plaster with mica:
the second type is 5%cross woven fiberglass in off-white limestone plaster with mica:the third type
is off-white and brown plant fiber paper layers:the fourth type is 1%plant tiber in wh ite gypsum
plaster.This sample is non-homogeneous.Asbestos is none detected.
The first type is 5%of the sample.The second type is 5%of the sample.The third type is 5%of
the sample.The fourt h type is 85%ofthe sample.
Lab H197! 8.Field '\108 I S-5 \\'all System
This sa mple contains off-white paint.white limestone plaster with .bro wn and off-wh ite plant tibe r
paper.and white gypsum plaster with 1%plant fiber.This sample is non-homogeneous.Asbestos
is none detected.
The paint is I%of the sample.The plaster with limestone is 9% of the sample"The pla nt tiber
paper is 5%ofthe sample.The white gypsum plaster is 85%of the sample.
Lab HI97!9.Field A I081S-6 Wall System
Thi s sample contains wh ite paint.white gypsum plaster with mica .brown and off-white plant fiber
paper.and wh ite gypsum plaster wit h 1%plan t fiber. Th is sample is non-homogeneou s"Asbestos
is no ne detected.
The paint is 1% of the sample.The plaste r with mica is 9% of the sample.The plant fiber paper is
5%of the sample.The white gypsum plaster is 85%ofthe sample.
Batch "104900
Lab #1-/1 9724 -H 19743
Page 3 of 5
Lab 1-/1 9730.Field A 1OS 1S-7 Vinvl Floor Sheeting
This sample contains two types ofmaterial:The first type is gray plastic :the second type is 35%
plant fiber.5%fiber glass and 5%synthetic fiber in gray bindcr. This sample is non-homogeneous.
Asbestos is none detected.
The first type is 60%of the sample.The seco nd type is 40%ofthc sample.
~ab 11 19731. Field Al 081S-8 Vinyl Floo r Sheeting
Th is sample contains two type s ofmaterial:The first type is off-white paint:the second type is gray
rubber and limestone.Thi s sample is non-homogene ous. Asbestos is none d etected.
Th e first type is 1%of the sample.The second type is 99%ofthe sample.
Lab H19737 .Field A l 081S-9 Vinyl Floor Sheeting
This sample contains two types of material:The first type is white paint:the seco nd type is gray
rubber and limestone.This sample is non-homogeneous.Asbestos is none detected .
The first type is I%of the sample. The second type is 99% of the sample.
Lab 1-1 19733.Field A I081S-10 Floor Tile
This is pink plastic and limestone tile with debris on the surface. Asbestos is no ne detected.
Lab H19 7'4.Field AI08 1S-l l Floor Tile
Thissample contains three types ofmaterial:The first type is 12%ebrysotile asbestos in tan plastic
and limestone tile:the second type is black tar mast ic:the third type is gray sandy plaster.Th is
sample is non-homogeneous.
The first type is 98%of thc sample. The second type is 1%ofthc sample.The third type is 1%of
the sample.
Lab 111 9735. Field A1081S-Il Floor Tile
This is 15%chrysotile asbestos in a tan plastic and limestone tile.
Note: The black tar mastic contains greater than 1%ch rysotile asbestos.
The tile is 99%ofthe sample.The black tar mast ic is 1%of thc sample.
Lab 1-/19736.Field A1081S-13 Floor Tile Mastic
This is 8%ch rys otile asb estos in black tar mas tic.
Batch"104900
Lab #HI9724 -HI 9743
Page 4 of5
Lab II 1973 7.Field .';'1 OS 1S-14 Floor Tile
This is a gray plastic and limestone tile with yellow resin mastic . Asbestos is none d etected.
The tile is 99%of the sample. Th e mastic is 1%of the sample.
Lab 11 IQ/38 .Field AI08 1S-15 Cove Base Adhesive (Tan)
This sample contains three types of material:The first type is tan mastic with limestone:the second
type is white paint:the third type is white limestone plaster with mica.This sample is non-
homogeneous.As bestos is none detected.
The first type is 94%of the sample. The second type is 1%of the sam ple.The third type is 5%of
the sample.
Lab 11 19739.Field A I081S-16 CO\'e Base Adhesive (Brown)
This sample contains two types of material:The first type is brown resin mastic:the second type is
white limestone plaster with mica.This sample is non-homogeneous.Asbestos is none detected .
The first type is 80%of the sample. The second type is 20% of the sample.
Lab 11 19740 .Field A 108IS-17 Cove Base Adhesive
This sample contains two types of material:The first type is tan mastic with limestone:the second
type is brown plant fiber paper. This sample is non-homogeneous.Asbestos is none detected.
The first type is 99%of the sample.The second type is 1%of the sample.
Lab H I974 1.Field A I081S-I8 Duct Sealant
This is gray sealant with limestone.Asbestos is no ne detected.
Lab HI 974".Field A1081S-19 Sink lindercoat
This is 5%organic fiber in white binder with limestone and mica.Asbes tos is none detected.
Batch s 104900
Lab s HI 9724 -H19743
Page 5 of 5
Lab H19743.Field AI081S-10 Surfacing Material
This sample contains three types of material: The first type is off-white paint:the second type is off-
white limestone plaster with mica:the third type isoff-white gypsum plaster with mica.This sampl e
is non-homogeneous.Asbestos is none detected.
The first type is 10%ofthe sample.The second type is 45% of the sample.The third type is 45%
of the sample.
In order to be sure reagents and tools used for analysis are not con taminated with asbestos.
blanks are tested.Asbestos was none detected in the blanks tested with this bulk sample set.
Very truly yours,
~.IJC
Steve H.O<on,President
~"
Dixon Information Inc.
78 West 2400 South
South Salt Lake,Utah 84115
Phone:[phone] Fax:[phone]
BULK ANALYTICAL REQUEST FORM
Turnaround Time -Circle One Batch Number IDlJ gOO
Rush (24 hours $25.00 per sample)
Non-rush (5 Working days $17.00 per sample)
/)el1;s.1?M/"es -p/,;,J-e M~.s....M ill.
Name oflocation sample was taken at::-:--=s:""h!..!o<-;e=--c--c-__-,-::-:----::-c-_-;-__---:::--_
Street address sample was taken at 6¥25"S:g,~hw"'tl/t)1 13/""",eI'nq ur
Sampled by:.I.0!?a h /<:lLL..'oJ
Description of Sample
Report to be sent to:L .,",0 Fa1",«-
Company:117'1 r"l1/ronmcnfaf
Address:c.ro.l!.N //m ln"-tk,,,we
City:$1,c.State:c/U T
Zip Code:¥'/IlJ ~
Telephone #:caDI)%6 -Z2Z3
Fax #:("01)i"·,"/~
E-mail:Il"o/~&iltl -e......CoM.
Lab #
12 V-A./oal _
Samples Collected
Date Time
Billingto be sent to:----:-_
Company:I HI L'n"''ronn7~'lot.../
Address:-----:::-_
City:State:_
Zip Code:,-c-_
Telephone #:_
Fax #:_-;-::-:-;----:-:-::-::-:-_
PO #:_-'--_-'------"'-'_
Floot"tile
f:{ool a le.
Field #
A l oalS-
II
f'Z.
!3
Flo",..tde.
~V~bose:dlu:s.'ve..,(ra., )
Col''''-"'oS'"..d hes/....t!:.-('-raul,.,)
/1
S'nfc .H7det"c.o~-{-­
S'~y.f4.Co,;>!!,.,.,,,,,--f~;&d-
Chain ofCustody
Submission of asbestos samples for analysis and/or signing a chain of custody is the
equivalent of submission of a purchase order and constitutes an agreement to pay for services
provided at Dixon Informat~Inc::g'0rated standard schedule offees for services,
Submitted by:~-'.::Date:'I'-11 ~Time:_
Received b~':Q;;:;:;;;;Date:U ;;Time:\~'l..()
Received by Analyst:~-Date:t:.f 2 -/L Time:/bdJ
Returned by Lab:Date:Time: _
Appendix"A"
"This report relates only to the items tested. Thi s repo rt must not be used to claim
prod uct endorsement by NVLAP or A IHA ."
NV LA P and A IHA requires laboratories to state the conditio n of samples received for
testing: Th ese samples are in acceptable co ndition for analysis unless there is a statement
in the report of analysis that a test item has some character istics or condition that
precludes analysis or req uires a modification of standard analytica l methodology.II'a test
item is not acceptable,the reasons for non-acce ptability will be give n under the
lab oratory num ber for that particular test itcm.The reported percentages of each material
type are based on the sample recei ved by the laboratory and may not be representative of
the parent material.Or ientation of top and bottom may not be specified due to uncertainty
of orientation.
M ethods of Ana lysis and Limit of Detection
in a ir count analysis.the results may be biased when interferences arc noted.
The accuracy of asbestos analysis in bulk samples increases with increasing
concentration of asbestos.Pigment s.binders. small sample size.and multiple layers may
affect the analysis sensitivity.
There are two methods for ana lysis of as bestos in a bulk test sample. Visual
esti mation is the most sensitive method.If an analyst makes a patient sea rch. 0.1%or less
asbestos can be detected in a bulk sample.
The second method of analysis is a statistical approac h ca lled po int counting.EPA
will not acc ept visual estimations if a laboratory detects a trace of asbestos in a sample
i.e.anything less than I%asbesto s.Government age ncies regulate asbestos containing
materials (AC M) whenever the ACM is more than I%.OS HA require men ts apply on
samples co ntaining any amount of asbestos.
Due to the higher charge for a point count analysis,Dixon Information Inc.does not
perform a point count unless authorized to do so by the client.If a sample is po int
counted,when possible,various chemica l and/or physical means may be used to
concentrate the asbestos in the sample.This is permitted by the EPA method and it
increases the accuracy of the analysis.

Appendix E
Regulatory Factors

Several factors determine how asbestos in a building must be treated if it has the potential of
being disturbed during a renovation or demolition. These factors include the following:

Factor
EPA Regulations for
Asbestos Removal
OSHA Regulations for
Asbestos Removal
Definition of asbestos
in a building material
Defines ACM as a material
containing 1% or greater asbestos.
Defines an ACM as one containing
>1% asbestos.
Regulation of asbestos
in building materials
Regulates only ACM. If the asbestos
concentration in a material is shown
to be “none detected” by initial
analysis or 1% or less by point count
analysis, EPA/DAQ does not regulate
it.
Regulates not only ACM but all
materials containing any amount of
asbestos. Regulations are not as
stringent for materials containing
equal-to or less-than 1% asbestos but
greater than a “none detected”
concentration.
Determination of
asbestos concentration
in a gypsum board
wall system
Allows compositing of all layers
(joint compound, joint tape, and
gypsum board) into one sample,
which decreases the possibility that
the sample will be evaluated as an
ACM.
Requires that each layer of the wall
system be analyzed and reported
independently, which increases the
possibility of a sample containing
ACM or identifiable asbestos.
Defines regulated and
non-regulated ACM
Yes – Regulated ACM include friable
ACM and resilient flooring, asphalt
roofing, gaskets and packing that
have become friable and other ACM
that have a high probability of
becoming friable.
No – Requirements for asbestos work
procedures and worker training are
less stringent for resilient flooring,
asphalt roofing materials, and
materials containing greater than
“none detected” but not greater than
1% asbestos.
Notification of
asbestos abatement or
building demolition
required
Yes – Utah DAQ must be notified on
the appropriate form 10 working-days
prior to an asbestos abatement of
regulated asbestos material greater
than the NESHAP-established
notifiable quantity with demolition, or
demolition where abatement is not
required.
No – Not required.
Provision for allowing
ACM to remain in a
building during a
demolition.
Yes – Allows ACM resilient flooring,
asphalt roofing, and certain other non-
friable building materials in good
condition to remain in a building
during demolition as long as the
demolition process will not render
them friable.
No – If any asbestos is left in a
building during a demolition, the
demolition workers are expected to
meet the same OSHA requirements
that an abatement contractor would
meet if an abatement contractor was
conducting an abatement of those
materials.

Appendix F
Project Limitations

PROJECT LIMITATIONS
This Project was performed using, as a minimum, practices consistent with standards
acceptable within the industry at this time, and a level of diligence typically exercised by
EH&S consultants performing similar services.
The procedures used attempt to establish a balance between the competing goals of limiting
investigative and reporting costs and time, and reducing the uncertainty about unknown
conditions. Therefore, because the findings of this report were derived from the scope, costs,
time and other limitations, the conclusions should not be construed as a guarantee that all
universal, toxic and/or hazardous wastes have been identified and fully evaluated.
Furthermore, IHI assumes no responsibility for omissions or errors resulting from inaccurate
information, or data, provided by sources outside of IHI or from omissions or errors in public
records.
It is emphasized that the final decision on how much risk to accept always remains with the
client since IHI is not in a position to fully understand all of the client's needs. Clients with a
greater aversion to risk may want to take additional actions while others, with less aversion to
risk, may want to take no further action.

ATTACHMENT A.4

SX BUILDING
ASBESTOS INSPECTION REPORT

IIHHII
E NVIRONMENTAL

ASBESTOS INSPECTION REPORT

SX Building
White Mesa Mill-Denison Mines Corp
6425 South Highway 191
Blanding, Utah

August 1, 2012

Prepared for:
Ms. Jo Ann Tischler, Corporate Director of Compliance & Permitting
Denison Mines
1050 17th Street, Suite 950
Denver, Colorado 80265

Prepared by: Reviewed by:

Lono Folau
Asbestos Inspector #ASB-0537
Jon H. Self
Asbestos Program Manager

IHI Project 12U-A1081
640 EAST WILMINGTON AVE SALT LAKE CITY UT 84106 TELEPHONE: [phone] FAX: [phone] E-MAIL: [e-mail]

SALT LAKE CITY SAN FRANCISCO PHOENIX DENVER SEATTLE

TABLE OF CONTENTS

EXECUTIVE SUMMARY .............................................................................................................. I 
1.0 INTRODUCTION ..............................................................................................................1 
2.0  BUILDING DESCRIPTION ................................................................................................1 
3.0 INSPECTION PROCEDURES ............................................................................................2 
3.1 Asbestos-Containing Material (ACM) ...............................................................2 
3.2 Bulk Sampling ...................................................................................................2 
3.3 Bulk Sample Analysis ........................................................................................3 
4.0 INSPECTION RESULTS ....................................................................................................4 
4.1 Asbestos-Containing Materials ..........................................................................4 
4.2 Non-Asbestos-Containing Materials ..................................................................4 
4.3 Bulk Sample Analytical Results ........................................................................4 
4.4 Damage and Hazard Assessment .......................................................................5 
4.5 Materials Requiring Special Considerations ......................................................5 
4.6 Assumed Asbestos-Containing Materials ..........................................................5 
4.7 Inaccessible Areas ..............................................................................................5 
4.8 Materials Assumed >1% Asbestos (no NESHAP point count) .........................5 
5.0 RESPONSE ACTIONS ......................................................................................................6 
5.1 Applicable Rules and Regulations .....................................................................6 
5.2  Renovation and Demolition (EPA and OSHA) .................................................6 
6.0 COST ESTIMATES ..........................................................................................................7 

APPENDICES

Appendix A: Data Tables
Appendix B: Building Floor Plans
Appendix C: Photographs
Appendix D: Laboratory Results
Appendix E: Asbestos Regulatory Factors
Appendix F: Project Limitations

Denison Mines/SX Building-White Mesa Mill TOC - 1 IHI Environmental
Asbestos Inspection Project No. 12U-A1081

EXECUTIVE SUMMARY
On May 31, 2012, IHI Environmental conducted an asbestos inspection of the SX Building at
the Denison Mines White Mesa Mill site, in Blanding, Utah. Ms. Jo Ann Tischler, Corporate
Director of Compliance and Permitting for Denison Mines, requested this inspection to
identify the asbestos-containing materials (ACM) that exist in the building.
ACM – IHI identified the following materials:
• Pipe fitting sealant (20 units)
Conclusions
Asbestos – IHI recommends that a Utah-certified asbestos abatement contractor remove and
properly dispose of all the ACM in this building that may be disturbed during remodel or
demolition activities.
Cost Estimates
IHI’s cost estimates for a Utah-certified asbestos abatement contractor to remove the ACMs
outlined above are approximately $230. The estimated cost does not include travel expenses
for an abatement contractor. These estimates do not include the costs for asbestos abatement
design and management consulting services.
The report that follows this Executive Summary should be read in its entirety because it
includes important information, such as material descriptions and locations, regulatory
requirements, and building-specific recommended response actions.
Denison Mines/SX Building-White Mesa Mill i IHI Environmental
Asbestos Inspection Project No. 12U-A1081
Executive Summary
Asbestos-containing Materials by Homogeneous Area
White Mesa Mill-Denison Mines Corp
SX Building
Homogeneous
Area Number Material Description/Location Asbestos
Content Amount Cost
Estimate(1)
M001 3%20 unitsChrysotile
Mostly used on the TSI on the south corner
of building
Pipe Coating - White sealant on pipe
ends of fibrousglass insulation
$228
Cost Estimates include asbestos removal costs only; abatement design, management fees and
replacement costs are not included. Please refer to Section 6.0 for more details.
Note 1:
Executive Summary Table SX Building
White Mesa Mill-Denison Mines Corp
Page 1 of 1

ASBESTOS INSPECTION

SX Building
White Mesa Mill-Denison Mines Corp
6425 South Highway 191
Blanding, Utah

1.0 INTRODUCTION
On May 31, 2012, IHI Environmental conducted an asbestos inspection of the SX Building
located at 6425 South Highway 191 in Blanding, Utah. Ms. Jo Ann Tischler, of Denison
Mines Corporation, requested this inspection to identify asbestos-containing materials
(ACM) that exist in the facility.
2.0 BUILDING DESCRIPTION
• Building Identification
Building Name .............................SX Building
Building Address ........................6425 South Highway 191, Blanding, Utah 84511
• Building Construction
Building Construction Date .........1978
Renovations..................................Not known
Building Type .............................Plant
Building Total Sq. Ft....................50,850 square feet
Structural System ........................Concrete foundation with steel
Exterior Wall Construction .........Metal
Floor Deck Construction .............Concrete
Roof Deck Construction .............Metal
Roof Construction .......................Metal
• Floors
Floors Above Grade .................... One
Floors Below Grade .................... None
• Interior Finishes
Floors ...........................................Concrete
Walls ............................................ Metal
Denison Mines/SX Building-White Mesa Mill 1 IHI Environmental
Asbestos Inspection Project No. 12U-A1081

Ceilings ........................................ None (metal roof)
Attic ............................................. None
Basement ..................................... None
• Building Mechanical
Heating Plant ............................... Not known
Cooling Plant ............................... Not known
3.0 INSPECTION PROCEDURES
3.1 Asbestos-Containing Material (ACM)
IHI visually inspected all accessible areas of the building to identify suspect ACM. To assess
the condition and determine friability of the suspect materials, IHI visually examined and
touched all accessible surfaces, structures, and mechanical systems within the building.
Suspect ACM was identified and assessed by homogeneous areas. A homogeneous area is
defined as a single material, uniform in texture and appearance, installed at one time, and
unlikely to consist of more than one type, or formulation, of material. In cases where joint
compound and/or tape has been applied to wallboard (gypsum board) and cannot be visually
distinguished from the wallboard, it is considered an integral part of the wallboard and in
effect becomes one material forming a wall or ceiling “system."
Each homogeneous area was given a unique material identification (ID) number. Each ID
number begins with a letter: "S" for surfacing materials, "T" for thermal system insulation, or
"M" for miscellaneous materials. This letter is followed by a three-digit number, assigned in
consecutive order. This number is used to identify that specific homogeneous area
throughout the inspection report.
3.2 Bulk Sampling
To determine the asbestos content of materials, IHI collected bulk samples from all
accessible homogeneous areas of suspect ACM and submitted the samples to an accredited
laboratory for analysis.
The number of samples collected from each homogeneous area generally followed the U. S.
Environmental Protection Agency (EPA) Asbestos Hazard Emergency Response Act
(AHERA) regulations (40 CFR §763.86). Friable surfacing materials were sampled using the
Denison Mines/SX Building-White Mesa Mill 2 IHI Environmental
Asbestos Inspection Project No. 12U-A1081

Denison Mines/SX Building-White Mesa Mill 3 IHI Environmental
Asbestos Inspection Project No. 12U-A1081
random sampling scheme given in the EPA publication 560/5-85-030a, titled "Asbestos in
Buildings: Simplified Sampling Scheme for Friable Surfacing Materials." Bulk sample IDs
collected during the inspection were entered on chain-of-custody forms for submittal to the
analytical laboratory.
3.3 Bulk Sample Analysis
Bulk samples were analyzed using polarized light microscopy (PLM) and visual estimation
according to the EPA Interim Method for the Determination of Asbestos in Bulk Insulation
Samples, EPA-600/M4-82-020. Samples were analyzed by Dixon Information Inc. in Salt
Lake City, Utah. Dixon Information is accredited under the National Institute of Standards
and Technology, National Voluntary Laboratory Accreditation Program (NIST-NVLAP) for
bulk asbestos sample analysis, and is also accredited by the American Industrial Hygiene
Association (AIHA).
EPA’s National Emissions Standards for Hazardous Air Pollutants (NESHAP) and AHERA
regulations define ACM as material containing greater than 1% asbestos by weight; materials
containing 1% or less asbestos are not considered regulated ACM by the EPA. Further, the
NESHAP regulations state that any sample found to contain less than 10% asbestos but
greater than “none detected," by the visual estimation method used during PLM analysis,
must be assumed to contain greater than 1% asbestos unless confirmed by NESHAP point
counting analysis.1
Despite EPA (and Utah Division of Air Quality) rules exempting building materials
containing 1% or less asbestos from stringent regulation, Occupational Safety and Health
Administration (OSHA) regulations outline specific precautionary work practices when
employees work with materials containing even trace amounts of asbestos.2
The laboratory reports can be found in Appendix D of this report.

1 NESHAP point counting includes examining materials under a polarizing microscope using an eyepiece
reticule that superimposes a grid of points over the field of view. 400 points are examined. 2 OSHA regulations pertaining to asbestos in buildings include 29 CFR 1926.1101 and 29 CFR 1910.1001.
OSHA has also issued interpretive letters that provide clarification about how materials containing less than 1%
asbestos should be handled. (see www.osha.gov)

4.0 INSPECTION RESULTS
4.1 Asbestos-Containing Materials
The Executive Summary and Table 1 in Appendix A list all homogeneous areas that contain
asbestos. Each material is described by type of material, friability and visual appearance.
Friability is defined in accordance with EPA’s NESHAP regulations.
• “Friable ACM” is any material containing more than 1% asbestos (as determined by
PLM) that, when dry, may be crumbled, pulverized, or reduced to powder by hand
pressure and also includes non-friable ACM that may become friable during building
demolition.
• “Non-friable ACM” is any material containing more than 1% asbestos (as determined
by PLM) that, when dry, cannot be crumbled, pulverized, or reduced to powder by
hand pressure.
• “Category I non-friable ACM” are asbestos-containing resilient floor coverings
(commonly known as vinyl asbestos tile (VAT)), asphalt roofing products, packings,
and gaskets.
• “Category II non-friable ACM” encompasses all other non-friable ACM.
• “Non-friable RACM” is used to denote thermal system insulation that is in good
condition but would become friable during renovation or demolition and therefore is
"regulated asbestos containing material" (RACM).
4.2 Non-Asbestos-Containing Materials
Homogeneous areas of suspect ACM are identified as non-ACM if the material contains no
detectable asbestos. Table 2, located in Appendix A of this report, lists all homogeneous
areas that were found to be non-ACM.
4.3 Bulk Sample Analytical Results
Table 3, located in Appendix A of this report, lists all the bulk samples (chronologically by
sample number) collected from homogeneous areas of suspect ACM, and the laboratory
analytical results. Each sample was given a unique sample number. There may be more than
one sample number for the same homogeneous area of suspect ACM indicating multiple
samples were collected from that homogeneous material. The homogeneous areas of suspect
Denison Mines/SX Building-White Mesa Mill 4 IHI Environmental
Asbestos Inspection Project No. 12U-A1081

ACM are identified on this table by their material identification numbers. The sample
location listed on this table provides a brief, but specific, description of the location where
the sample was collected. This is different from the homogeneous area location provided on
Tables 1 and 2. Table 4 is the same as Table 3, except that the entries have been sorted by
homogeneous area number.
4.4 Damage and Hazard Assessment
Each homogeneous area of ACM was assessed for existing damage, accessibility, and
potential for future damage, this information is presented in Table 5, located in Appendix A
of this report. This table also lists the substrate beneath each homogeneous area of ACM.
Damage and hazard assessment categories are included in the tables in Appendix A.
4.5 Materials Requiring Special Considerations
None
4.6 Assumed Asbestos-Containing Materials
The asbestos pipe fitting sealant is white and applied on pipe fiberglass insulation ends and
plastic pipe insulation connections.
4.7 Inaccessible Areas
Suspect materials that were hidden or inaccessible may not have been characterized by this
inspection. Therefore, any material not identified in this report as having been tested should
be treated as suspect ACM until it has been sampled by a Utah-certified inspector and
analyzed by an accredited laboratory applying EPA methods.
In addition, some building structures may have been constructed after the application of
ACM, and therefore may have obscured these materials from visual examination during this
inspection. Typical scenarios include thermal system insulation inside hardened mechanical
chases, floor tile and mastic under walls, and sprayed-on texturing and fireproofing behind
structural supports or architectural features.
4.8 Materials Assumed >1% Asbestos (no NESHAP point count)
None
Denison Mines/SX Building-White Mesa Mill 5 IHI Environmental
Asbestos Inspection Project No. 12U-A1081

Denison Mines/SX Building-White Mesa Mill 6 IHI Environmental
Asbestos Inspection Project No. 12U-A1081
5.0 RESPONSE ACTIONS
5.1 Applicable Rules and Regulations
In Utah, EPA asbestos regulations are administered by the Utah Division of Air Quality
(DAQ).3 The Utah Occupational Safety and Health Administration (UOSH) has adopted the
Federal OSHA regulations.4 In addition, the Salt Lake Valley Health Department (SLVHD)
regulates demolition activities in Salt Lake County.5 The SLVHD regulations for pre-
demolition building inspections require an asbestos inspection, but also require building
owners to inspect the building for other hazardous materials such as universal wastes,
hazardous and toxic wastes, and lead-based paint. Like asbestos, these wastes, if present,
must be removed prior to building demolition.
Regulatory factors relevant to asbestos abatement decision-making are included in Appendix E.
5.2 Renovation and Demolition (EPA and OSHA)
A listing of ACM found during this inspection is presented in the Executive Summary at the
front of this report, and in Appendix A, Table 1.
NESHAP regulations require the removal of friable ACM and non-friable ACM that could
become friable during demolition or renovation activities. Therefore, we recommend that all
of the ACM in this building be removed and properly disposed of by a licensed asbestos
abatement contractor if total demolition of the facility is planned, or those materials that will
be impacted by renovation plans be removed prior to the commencement of renovation work.
Despite EPA (and Utah Division of Air Quality) rules exempting building materials
containing 1% or less asbestos from stringent regulation, Occupational Safety and Health
Administration (OSHA) regulations outline specific precautionary work practices when
employees work with materials containing even trace amounts of asbestos.6 Strict
3 R307-801. Asbestos, Utah Division of Air Quality Rules, Implementation of Toxic Substances Control Act
Title II, Asbestos Certification, Asbestos Training, notifications and Asbestos Work Practices for Renovations
and Demolitions (See www.airquality.utah.gov). 4 Asbestos, Tremolite, Anthophyllite, and Actinolite Standards, Chapter D (Construction), Section 58; and
Chapter Z (General Industry), Section 1001, Utah Occupational Safety and Health Rules and Regulations
(Administered by Utah Occupational Safety and Health Division) (See www.uosh.utah.gov). 5 Salt Lake City – County Health Department, Health Regulation #1 Section 12 (See www.slvhealth.org). 6 OSHA regulations pertaining to asbestos in buildings include 29 CFR 1926.1101 and 29 CFR 1910.1001.
OSHA has also issued interpretive letters that provide clarification about how materials containing less than 1%
asbestos should be handled. (see www.osha.gov)

Denison Mines/SX Building-White Mesa Mill 7 IHI Environmental
Asbestos Inspection Project No. 12U-A1081
compliance by building owners with the OSHA asbestos regulations may result in response
actions not required by the EPA and Utah DAQ for certain unregulated materials.
6.0 COST ESTIMATES
Details of the estimated removal costs by homogeneous area can be found in Table 6,
Appendix A, and in the Executive Summary table. These estimates are provided for
budgeting and planning only, and do not have a level of accuracy sufficient to be used as a
construction design cost estimate. The actual cost of asbestos removal is dependent on
factors such as the size of the job, the required time frame for removal, the time of year the
job is conducted, and economic factors. These estimates do not include replacement costs, or
the cost for asbestos abatement design and management consulting services.

Appendix A
Data Tables

Table 1
Asbestos-containing Materials by Homogeneous Area
White Mesa Mill-Denison Mines Corp
SX Building
Homogeneous
Area Number Material Description/Location
Asbestos
Content AmountFriability
M001
White sealant on pipe ends of fibrousglass
insulation
Mostly used on the TSI on the south corner of
building
3%20Category 2
Non-friable
Pipe Insulation Sealant unitsChrysotile
Asbestos Survey Report - Table 1 SX BuildingPage 1 of 1
White Mesa Mill-Denison Mines Corp
Note: A homogeneous area of suspect material is considered an Asbestos-containing Material (ACM) if any one sample contains greater than 1% asbestos
Table 2
Homogeneous Areas That Do Not Contain Asbestos
White Mesa Mill-Denison Mines Corp
SX Building
Material DescriptionHomogeneous
Area Number Material Description/Location Amount
M002
Clear rubber silicone gasket
On gaskets of tanks on center of building
15 unitsGasket
M003
Tan rubber silicone gasket
On gaskets of tanks on west of building
10 unitsGasket
M004
White rubber silicone gasket
On gaskets of tanks scattered throughout
building
20 unitsGasket
Asbestos Survey Report - Table 2 Page 1 of 1 SX Building
White Mesa Mill-Denison Mines Corp
Table 3
Bulk Sample Analytical Results by Sample Number
White Mesa Mill-Denison Mines Corp
SX Building
Homogeneous
Area Number Material Sampled Analytical ResultsSample
Number Sample Location
A1081SX-1 M001 S. corner of building 3%ChrysotilePipe Insulation Sealant
A1081SX-2 M001 SE. corner of building 3%ChrysotilePipe Insulation Sealant
A1081SX-3 M001 N. corner of building 3%ChrysotilePipe Insulation Sealant
A1081SX-4 M002 Center of building NDGasket
A1081SX-5 M003 N. side of building NDGasket
A1081SX-6 M004 W. side of building NDGasket
Note: ND =No Asbestos Detected, NA= Not Analyzed, TR = <1% Asbestos, PC = Point Count
Asbestos Survey Report - Table 3 Page 1 of 1 SX Building
White Mesa Mill-Denison Mines Corp
Table 4
Bulk Sample Analytical Results by Homogeneous Area Number
White Mesa Mill-Denison Mines Corp
SX Building
Homogeneous
Area Number Material Sampled Analytical ResultsSample
Number Sample Location
A1081SX-1 M001 S. corner of building 3%ChrysotilePipe Insulation Sealant
A1081SX-2 M001 SE. corner of building 3%ChrysotilePipe Insulation Sealant
A1081SX-3 M001 N. corner of building 3%ChrysotilePipe Insulation Sealant
A1081SX-4 M002 Center of building NDGasket
A1081SX-5 M003 N. side of building NDGasket
A1081SX-6 M004 W. side of building NDGasket
Note: ND =No Asbestos Detected, NA= Not Analyzed, TR = <1% Asbestos, PC = Point Count
Asbestos Survey Report - Table 4 Page 1 of 1 SX Building
White Mesa Mill-Denison Mines Corp
Table 5
Damage and Hazard Assessment by Homogeneous Area
White Mesa Mill-Denison Mines Corp
SX Building
Homogeneous
Area Number DamageSubstrate AccessibilityMaterial
Type
Assessment
Category
Disturbance
Potential
M001 5 Slight Damage Rarely AccessedMetal MediumPipe Insulation Sealant
Damage Categories
Each homogeneous area of ACM was classified into one of the following seven categories, as specified in
EPA’s AHERA regulations (40 CFR §763.88):
(1) Damaged or significantly damaged thermal system insulation ACM.
(2) Damaged friable surfacing ACM.
(3) Significantly damaged friable surfacing ACM.
(4) Damaged or significantly damaged friable miscellaneous ACM.
(5) ACBM with potential for damage.
(6) ACBM with potential for significant damage.
(7) Any remaining friable ACBM or friable suspected ACBM.
(X) Not applicable (material is non-friable surfacing or miscellaneous material).

The damage categories are defined as follows:
“Undamaged” means the material had no visible damage, or extremely minor damage or surface
marring (i.e., a room full of floor tile with only two or three small corners chipped off of the tile).
“Slight Damage” means the material had visible damage evenly distributed over less than 10% of its
surface, or localized over less than 25% of its surface.
“Significantly Damaged” means the material had visible damage that is evenly distributed over 10% or
more of its surface or localized over 25% or more of its surface.

Hazard Assessment Categories
Each homogeneous area of ACM was evaluated for accessibility and the hazard the material presents to
building occupants and the general public. The assessment assumes a fully occupied building.
“Inaccessible” means the material was located in an area that people had no reason to enter and could
not access without special measures. One example would be above a solid ceiling.
“Rarely-Accessed” identifies a material that was in a location that could be accessed but wasn't unless
there was a specific needed. An example would be a pipe tunnel. Another example would be a high
ceiling that is out of reach and not subject to any specific disturbances.
“Periodic Access” identifies a material that was in a location that was accessible, was not occupied full
time, but was accessed on a routine basis. An example would be a mechanical room or boiler room.
“Continuous Access” identifies a material that was in a location that was occupied full time and was
within reach of the occupants, or was frequently subject to direct disturbance. Examples would be
exposed floor tile or a normal height ceiling.
Asbestos Survey Report - Table 5 Page 1 of 1 SX Building
White Mesa Mill-Denison Mines Corp
Table 6
Estimated Abatement Costs by Homogeneous Area
White Mesa Mill-Denison Mines Corp
SX Building
Homogeneous
Area Number Material Extended
CostAmountUnit Cost
M001 Pipe Coating 20 units $11.42 $228
Total Estimated Abatement Cost $228
Note: Estimated abatement costs do not include replacement costs or costs for a consultant to manage the abatement.
Asbestos Survey Report - Table 6 Page 1 of 1 SX Building
White Mesa Mill-Denison Mines Corp

Appendix B
Building Floor Plans

1 2
6 5
4
3
SX Building
Sample Location & Number10
Explanation
Asbestos-containing pipe insulation sealant
PROJECT No:
SHEET:
DRAWN BY:
REVIEWED BY:
De
n
i
s
o
n

M
i
n
e
s

C
o
r
p
.
Wh
i
t
e

M
e
s
a

M
i
l
l
64
2
5

S
o
u
t
h

H
i
g
h
w
a
y

1
9
1
Bl
a
n
d
i
n
g
,
U
T
As
b
e
s
t
o
s

&

H
a
z
a
r
d
o
u
s

M
a
t
e
r
i
a
l
s

S
a
m
p
l
e

L
o
c
a
t
i
o
n

M
a
p
DATE:
DATE:
DATE:
REVISED BY:
640 E. Wilmington Ave.
Salt Lake City, UT 84106801.466.2223
[e-mail]
0 20'40'
12U-A1081
1 of 1
Keith
07-11-2012

N
V:\
-

1
2

P
r
o
j
e
c
t
s
\
1
2
U
-
A
1
0
8
1

D
e
n
i
s
o
n

M
i
l
l

S
i
t
e

A
s
b
e
s
t
o
s

I
n
s
p

&

M
P
\
D
r
a
w
i
n
g
s
\
1
2
U
A
1
0
8
1
.
d
w
g
,

s
x

b
l
d
g
,

7
/
3
1
/
2
0
1
2

3
:
1
1
:
4
9

P
M
,

k
e
i
t
h
f
,

A
N
S
I

f
u
l
l

b
l
e
e
d

B

(
1
7
.
0
0

x

1
1
.
0
0

I
n
c
h
e
s
)

Appendix C
Photographs

Photograph 1
The white sealant used on the bottom
pipe plastic insulation “T” contained
3% chrysotile asbestos. This is the
only asbestos-containing material in
the building.

Photograph 2
The other suspect asbestos materials
identified in the SX Building were the
gaskets. The gaskets did not contain
asbestos.

Photograph 3
A general view of the SX Building.

Appendix D
Laboratory Results

DIXON INFORMATION INC.---------,
MICROSCOPY,ASBESTOS ANALYSIS &CONSULTING
A.I.HA ACCREDITED LABORATO RY #101579
NVLAP LAB CODE 10101 2-0
June 13,2012
Mr.Lono Folau
IHI Environmental
640 East Wilm ington Ave
Salt Lake City,UT 84106
Ref:Batch #104909,Lab #H1975 I -HI9756
Received June 6,20 12
Test report Page I of 2
Denison Mines-White Mesa Mill
SX Buildin g
6425 S Highway 191,Blanding UT
Proj#12U-A1081
Sampled by Lono Folau
Dear Mr. Folau:
Samples H1975 1 through H19756 have been analyzed by visual estimation based on EPA-
600/M4-82-020 December 1982 optical microscopy test method,with guidance from the
EPA /6001R-931l1 6 July 1993 andOSHA ill 191 methods. Appendix "A"contains statements which
an accredited laboratory must make to meet the requirements of accrediting agencies.It also
contains additional information about the method ofanalysis.Th is analysis is accredited by NVLAP.
Appendix "A"must be included as an essential part of this test report.The data for this report is
accredited by NVLAP for laboratory number 101012-0.It does not contain data or calibrations for
tests performed under the AIHA program under lab code 101579.
This report may be reproduced but all reproduction must be in full unless written approval
is received from the laboratory for partial reproduction .The results of analysis are as follows:
Lab H19751.Field 1 Pipe insulation sealant
This sample contains two types of material:The first type is 90%glass woo l in yellow resin;the
second type is 3 %chrysotile asbestos,3%talc fiber'and 2 %tremolite clea vage fragments'in
off-wh ite binder.This sample is non-homogeneous.
The first type is 5%of the sample.The second type is 95%of the sample.
Lab H19752.Field 2 Pipe insulation sealant
This sample contains two types of material: The first type is 3%chrysotile asbestos,2%talc fiber'
and 2 %tremolite cleavage fragm ents'and 3%cross woven fiberglass in off-w hite binder with
debris: the second type is 98%glass wool in yellow resin.This sample is non-homogeneous.
The first type is 97%of the sample.The second type is 3%of the sample.L-+-78 W EST 2400 SOUTH ·SOUTH SALT LAKE,UTAH 84115-3013 ----+-
PHONE [phone]·FAX [phone] · RES.801-571-7695
Batch #104909
Lab #H1975 1 -Hl 9756
Page 2 of 2
Lab H19753.Field 3 Pipe insulation sealant
This sample contains two types of material: The first type is 3%chrysotile as bestos,3%talc fiber '
and 2%tremolite cleavage fragments' in off-white binder withdebris;the second type is 98%glass
wool in yellow resin. This sample is non-homogeneous.
The first type is 90%of the sample.The second type is 10%of the sample.
Lab H19754,Field 4 Tank gasket sealant
This is clear silicone rubber with debris.Asbestos is none detected.
Lab H19755, Field 5 Tank gasket sealant
This is tan silicone rubber with debris.Asbestos is none detected.
Lab H19756.Field 6 Tank gasket sealant
This is off-white silicone with debris.Asbestos is none detected.
'Note:Under certain geologic conditions, talc and amphibole minerals occur in the same deposit.
In some of those deposits,asbestiform fibers grow.The chemical composition and crystal structure
of these fibers range between that of talc and that of anthophyllite,the fibers are asbestiforrn
mineraloids which can be very difficult to characterize by PLM and/or TEM .
'Note:Some of the tremolite cleavage fragments have an aspect ratio exceeding 3:1.EPA 6001M4-
82-020 defines asbestos as being positively identified as one of the minerals listed in Table I-I with
an aspect ratio exceeding 3:I.Guidance from EPA/6001R-93-116 would not classify this tremolite
as asbestos.as the mean aspect ratio does not exceed 20:I.OSHA ill 191 has exempted tremolite
cleavage fragments from inclusion in the OSHA asbestos standard.
In order to be sure reagents and tools used for analysis are not contaminated with asbestos.
blanks are tested.Asbestos was none detected in the blanks tested with this bulk sample set.
Very truly yours,
~.
Steve H.Dixon.President
Analyst:Dustin Fritchman ~:~rt~
Analyst: Jaron D.Dixon ~D:-¥-Date Analyzed:June 13,2012
Turnaround Time -Circle One
Dixon Information Inc.
78 West 2400 South
South Salt Lake,Utah 84115
Phone:[phone] Fax:[phone]
BULKANALYTICAL REQUEST FORM
Batch Number /ot.J--9V1
R ush (24 hours $25.00 per sample)
Non-rush (5 Working days $17.00 per sample)
1J~"i$.""Mi;!'!&-UJhilt:lI1esc....M;lt
Name of location sample was taken at:-c-:~s"~)f,--_B=-:,t.<",;-=L-"d.,,-("-,nijWr--_----:::-c-_-c-__-=-=,-----_
Street address sample was taken at 1:,'(2S s./I~.hul"!Y 191 i /S1-tndr'nS 'UT
Sampled by:~CyTO .!b/BAh-
Description of Sample Lab #
Report to be sent to:L~hlcu<-
Company:Iii/Envl....onMeot<:2L
Address:tfJtoE.Wi lh1i",oi'6J?Me.
City::5'-C State:oJu r
Zip Code:gJ{IO~
Telephone #:(8~1)'I66 -222.'1
Fax #:(g6!}i/,/,-9'1(.,
E-mail:!7~(~ih ;-en'!.CAm
Field #
A I0815X
Billing to be sent to:
Company:I IfI -E.-t1->'-I-'-·r-~-n-W/-~--t"-cd-----'--
Address:-------,------City:::---c,-----State:_
Zip Code:-;:-_
Telephone #:_
Fax #:----,--,----------,:-:-----:----;-------PO #:12.II -A 108 I--------- ---- ------- -
Samples Collected
Date Time
I .R-e e ,n.s~la-ft'"...,sea/aN7 t $"/q 7 5/I2.~./0 7 2 1-
.3 177ez ~
'I -TAn k.Jasl:ef seMWVli;-/7 7:5lf
5 10 /97'7'5,5"/,i''l../"17-:510
Chain of Custody
Submission of asbestos samples for analysis and/or signing a chain of custody is the
equivalent of submission of a purchase order and constitutes an agreement to pay for services
provided at Dixon Information Inco orated standard schedule of fees for services.
Submitted by:~~~""'::-4f'!=...=~~---
Received b a ~~~~~~~~~~=:~;:::Received by Analyst:
Returned by Lab:_
\'':,2 0
//OCJ
)
A ppendix "A"
"This report relates only to thc items tcsted.This report must not be used to claim
product endorsement by NVLAP or AIHA."
N VLAP and AIHA requires laboratories to state thc condition ofsamples received for
testing:Th ese samples are in acceptable condition for analysis unless there is a statement
in thc report of analysis that a test item has some characteristics or co ndition that
precludes analysis or requi res a modification of standard analytical methodology.If a test
item is not ac ceptable,the reasons for non-acceptability will be given under the
laboratory number for that particular test item.The reported percentages of eac h material
type are based on the sample received by the laboratory and may not be representative of
the parent material.Orientation oftop and bottom may not be specified due to uncertainty
oforientation.
Methods of Analysis and Limit of Detection
In air count analysis,the results may bc biased when interferences are noted.
The acc urac y of asbestos analysis in bulk samples increases with increasing
co ncentration of asbestos.Pigments,binders,small sample size,and mul tipic layers may
affect the analysis sensitivity.
There arc two methods for ana lysis of asbestos in a bulk test sample.Visual
est imation is the most sensitive method.Ifan analys t makes a patient search,0.1%or less
asbestos can bc detected in a bulk sample.
The second meth od of ana lysis is a statistical approach called point counting.EPA
will not accept visual estimations if a laboratory detects a trace of asbestos in a sample
i.e.anything Icss than I%asbestos.Government agencies regulate asbestos containing
materials (ACM) whenever the ACM is more than I%.OS HA requirements app ly on
samples containing any amount ofasbestos.
Due to the higher charge for a point count analysis,Dixon Information Inc.do cs not
perform a point co unt unless authorized to do so by the cl ient.If a sample is point
counted, when possible,various chemical and/or physical means may be uscd to
concentrate the asbestos in the sample. Th is is permitt ed by the EPA method and it
increases the accuracy ofthe analysis.

Appendix E
Regulatory Factors

Several factors determine how asbestos in a building must be treated if it has the potential of
being disturbed during a renovation or demolition. These factors include the following:

Factor
EPA Regulations for
Asbestos Removal
OSHA Regulations for
Asbestos Removal
Definition of asbestos
in a building material
Defines ACM as a material
containing 1% or greater asbestos.
Defines an ACM as one containing
>1% asbestos.
Regulation of asbestos
in building materials
Regulates only ACM. If the asbestos
concentration in a material is shown
to be “none detected” by initial
analysis or 1% or less by point count
analysis, EPA/DAQ does not regulate
it.
Regulates not only ACM but all
materials containing any amount of
asbestos. Regulations are not as
stringent for materials containing
equal-to or less-than 1% asbestos but
greater than a “none detected”
concentration.
Determination of
asbestos concentration
in a gypsum board
wall system
Allows compositing of all layers
(joint compound, joint tape, and
gypsum board) into one sample,
which decreases the possibility that
the sample will be evaluated as an
ACM.
Requires that each layer of the wall
system be analyzed and reported
independently, which increases the
possibility of a sample containing
ACM or identifiable asbestos.
Defines regulated and
non-regulated ACM
Yes – Regulated ACM include friable
ACM and resilient flooring, asphalt
roofing, gaskets and packing that
have become friable and other ACM
that have a high probability of
becoming friable.
No – Requirements for asbestos work
procedures and worker training are
less stringent for resilient flooring,
asphalt roofing materials, and
materials containing greater than
“none detected” but not greater than
1% asbestos.
Notification of
asbestos abatement or
building demolition
required
Yes – Utah DAQ must be notified on
the appropriate form 10 working-days
prior to an asbestos abatement of
regulated asbestos material greater
than the NESHAP-established
notifiable quantity with demolition, or
demolition where abatement is not
required.
No – Not required.
Provision for allowing
ACM to remain in a
building during a
demolition.
Yes – Allows ACM resilient flooring,
asphalt roofing, and certain other non-
friable building materials in good
condition to remain in a building
during demolition as long as the
demolition process will not render
them friable.
No – If any asbestos is left in a
building during a demolition, the
demolition workers are expected to
meet the same OSHA requirements
that an abatement contractor would
meet if an abatement contractor was
conducting an abatement of those
materials.

Appendix F
Project Limitations

PROJECT LIMITATIONS
This Project was performed using, as a minimum, practices consistent with standards
acceptable within the industry at this time, and a level of diligence typically exercised by
EH&S consultants performing similar services.
The procedures used attempt to establish a balance between the competing goals of limiting
investigative and reporting costs and time, and reducing the uncertainty about unknown
conditions. Therefore, because the findings of this report were derived from the scope, costs,
time and other limitations, the conclusions should not be construed as a guarantee that all
universal, toxic and/or hazardous wastes have been identified and fully evaluated.
Furthermore, IHI assumes no responsibility for omissions or errors resulting from inaccurate
information, or data, provided by sources outside of IHI or from omissions or errors in public
records.
It is emphasized that the final decision on how much risk to accept always remains with the
client since IHI is not in a position to fully understand all of the client's needs. Clients with a
greater aversion to risk may want to take additional actions while others, with less aversion to
risk, may want to take no further action.

ATTACHMENT B

SUPPORTING DOCUMENTATION FOR INTERROGATORY 02/1:

APRIL 2012 COVER MATERIAL FIELD INVESTIGATION AND
LABORATORY TESTING RESULTS

ATTACHMENT B.1

APRIL 2012 COVER MATERIAL FIELD INVESTIGATION TEST PIT LOGS

SCALE
APPROX LIMITS OF BORROW STOCKPILE
~--300 a 300
MWH 2012 TEST PITS
MWH 2010 TEST PITS
EXISTING GROUND CONTOUR
(201 1 L1DAR SURVEY)
ELEVATION OF PROPOSED TOP OF COVER
EXISTING SPOT ELEVATION
-5560-
LEGEND
PROJECT
OENISOJ)~ ~
WHITE MESA MILL TAILINGS RECLAMATION G MWHTITLE
MINES COVER MATERIAL BORROW STOCKPILES DATE FIGURE 1DenisonMines(USA)Corp TEST PIT LOCATIONS
AUG 2012
FILE NAME
1009740 BRW
GRAVELLY SAND
TEST PIT LOG
LEGEND
GRAVELLY SAND
TEST PIT LOG
LEGEND
FINE SAND
TEST PIT LOG
LEGEND
FINE SAND
TEST PIT LOG
LEGEND
GRAVELLY SAND
TEST PIT LOG
LEGEND
GRAVELLY SAND
TEST PIT LOG
LEGEND
COARSE SAND
TEST PIT LOG
LEGEND
SAND
TEST PIT LOG
LEGEND
FINE SAND
TEST PIT LOG
LEGEND
CLAYEY SAND
TEST PIT LOG
LEGEND
CLAYEY SAND
TEST PIT LOG
LEGEND

ATTACHMENT B.2

LABORATORY TESTING RESULTS

DENISON MINES WHITE MESA MILL
Table 1.  Summary of Laboratory Testing Results for Borrow Stockpiles
Borrow 
Stockpile ID
Estimated 
Stockpile 
Volume1 (cy)
Field 
Investigation 
Date Material Description USCS
Sample 
ID
Sample 
Depth (ft)
Gravimetric 
Water 
Content (%)
Atterberg Limits2 
LL/PL/PI (%) PI
Specific 
Gravity % Gravel %Sand %Silt % Clay % Fines
E1 15,900 Apr‐2012 Topsoil (Sandy Silty Clay) CL‐ML E1‐A0 ‐ 3 ‐‐23/18/5 5 2.61 0 41 43 16 59 118 11 1.3 x 10‐4 5.2 6.6 Topsoil
SM A 5 4.5 NP NP ‐‐0.5 77.1 13.5 8.9 22 4.4 B
SC B 12 5.7 23.3/11.2/12.1 12.1 2.64 13.1 50.3 22.6 14.0 37 6.0 U
E3 16,800 Apr‐2012 Clay with Sand CH E3‐A0 ‐ 3 ‐‐54/24/30 30 2.53 0 23 29 48 77 105 19 9.5 x 10‐5 13.6 16.5 F
E4 66,600 Oct‐2010 Sandy Clay CL A 5 8.6 30.3/14.4/15.9 15.9 ‐‐0.0 41.2 39.1 19.7 59 7.7 U
Oct‐2010 Sandy Clay CL A 6 9.0 33.2/14.3/18.9 18.9 ‐‐0.0 35.5 38.1 26.4 65 9.8 F
Apr‐2012 Clay with Sand CH E5‐B0 ‐ 3 ‐‐51/24/27 27 2.56 2 15 36 47 83 16.2 F
E6 100,700 Oct‐2010 Clay CL A 5 14.4 40.2/15.8/24.4 24.4 2.74 0.1 17.7 49.5 32.7 82 11.8 F
E7 74,900 Oct‐2010 Sandy Clay CL A 6 5.7 26.2/16.3/9.9 9.9 ‐‐0.0 30.2 56.1 13.7 70 5.9 U
Oct‐2010 Sandy Clay CL A 2 7.4 23.0/12.0/11.0 11.0 ‐‐0.0 47.0 36.9 16.1 53 6.6 U
Apr‐2012 Gravel with Clay and Sand GW‐GC E8‐B0 ‐ 4 ‐‐27/16/11 11 2.63 40.0 31.0 18.0 11.0 29 125 11 6.0 5.0 B
W1 85,700 Oct‐2010 Sandy Clay CL A 5 8.8 32.1/14.5/17.6 17.6 ‐‐0.0 40.6 37.6 21.8 59 8.4 U
Oct‐2010 Sandy Clay CL A surface 8.5 28.1/13.1/15.0 15.0 ‐‐0.2 41.5 42.5 15.8 58 6.5 U
Apr‐2012 Clayey Sand with Gravel SC W2‐A0 ‐ 3 ‐‐24/14/10 10 2.62 30 45 15.0 10.0 25 6.9 4.7 B
Apr‐2012 Silty Clayey Sand with Gravel SC‐SM W2‐B0 ‐ 5 ‐‐18/13/5 5 2.63 41 45 9.0 5.0 14 128 9 1.5 x 10‐3 3.5 3.2 B
W3 84,800 Oct‐2010 Topsoil (Sandy Silty Clay) CL‐ML A surface 4.3 20.9/16.2/4.7 4.7 ‐‐0.2 44.2 39.2 16.4 56 6.7 Topsoil
Oct‐2010 Topsoil  (Sandy Silt) ML A 5 5.3 21.9/18.0/3.9 3.9 ‐‐0.0 32.6 54.3 13.1 67 5.7 Topsoil
Apr‐2012 Topsoil (Sandy Silty Clay) CL‐ML W4‐B0 ‐ 4 ‐‐26/19/7 7 2.60 0 38 44 18 62 7.2 Topsoil
Sandy Clay CL W5‐A0 ‐ 4 ‐‐27/18/9 9 2.61 1 49 32 18 50 7.0 7.2 U
Clayey Sand with Gravel SC W5‐B0 ‐ 4 ‐‐24/15/9 9 2.63 29 44 19 8 27 122 10 1.1 x 10‐3 3.6 4.1 B
W6 93,400 Oct‐2010 Topsoil (Sandy Silty Clay) CL‐ML A surface 3.3 23.1/16.5/6.6 6.6 ‐‐0.0 34.3 51.8 13.9 66 5.9 Topsoil
W7 39,500 Oct‐2010 Sandy Clay CL A 5 8.7 28.0/10.6/17.3 17.3 2.67 0.0 43.8 43.1 13.1 56 5.7 U
Silty Sand with Gravel SM W8‐A0 ‐ 3 ‐‐NP NP 2.64 35 51 9 5 14 117 13 1.2 x 10‐3 5.0 3.2 B
Silty Sand with Gravel SM W8‐B0 ‐ 4 ‐‐NP NP 2.66 32 40 18 10 28 6.4 4.7 B
Oct‐2010 Sandy Clay CL A surface 4.4 25.9/12.3/13.5 13.5 ‐‐0.0 37.4 45.2 17.4 63 7.0 U
Apr‐2012 Sandy Clay CL W9‐B0 ‐ 4 ‐‐28/16/12 12 2.63 6 44 35 15 50 115 14 4.1 x 10‐4 7.7 6.3 U
Notes:  14.0
1.  Volumes estimated using 2009 topography and assuming a relatively flat bottom surface, except for stockpiles W5, W8 and W9.  The volumes for stockpiles  W8 and W9 were estimated by comparing the 2011 versus 2009 topography.  
The volume for stockpile W5 was estimated using a combination of both methods.  
2.  LL = Liquid Limt, PL = Plastic Limit, PI = Plasticity Index (PI = LL‐PL)
3.  Gravel = 4.75 mm to 75 mm, Sand = 0.075 mm to 4.75 mm, Fines:  Silt = 0 .075 mm to 0.002 mm, Clay = less than 0.002 mm
4.  Group B (broadly graded), Group U (uniformly graded), and Group F (fine textured) based on evaluation of gradations and Benson (2012)*.   
*Benson, C., 2012.  Electronic communication from Craig Benson, University of Wisconsin‐Madison, to Melanie Davis, MWH Americas, Inc., regarding evaluation of gradations performed for potential cover soils for White Mesa, May 20.  
W9 60,250
Particle Size3
E8 227,300
W2 584,500
W4 90,000
W5 2,001,160 Apr‐2012
W8 178,411 Apr‐2012
E5 68,800
Gravimetric 
Water Content 
Est. using Rawls 
Eqn.3 (%)
E2 92,000 Oct‐2010 Silty Sand/Clayey Sand 
15 Bar 
Grav. 
Moist. 
Cont. (%)
Sat. Hyd. 
Conc. 
(cm/s)
Max. 
Density 
(pcf)
Opt. 
Moist. 
Cont. (%) Soil Group4
White Mesa_2010 and 2012 lab results_8‐6‐12.xlsx
2010 and 2012 Cover Soil Gradations_mmd.xlsx
0
20
40
60
80
100
0.00010.0010.010.1110100
Pe
r
c
e
n
t

F
i
n
e
r

(
%
)
Particle Size (mm)
E1-A (topsoil)
E3-A
E5-B
E8-B
W2-A
W2-B
W4-B (topsoil)
W5-A
W5-B
W8-A
W8-B
W9-B
E2A-2010
E2B-2010
E4-2010
E5-2010
E6-2010
E7-2010
E8-2010
W1-2010
W2-2010
W3-2010 (topsoil)
W4-2010 (topsoil)
W6-2010 (topsoil)
W7-2010
W9-2010
1.
5

i
n
c
h
Figure 1. White Mesa Cover Borrow Stockpiles Gradations from 2010 and
2012 Laboratory Testing
No
.

2
0
0
No
.

1
0
0
No
.

6
0
No
.

2
0
No
.

1
0
No
.

4
3/
8

i
n
c
h
3/
4

i
n
c
h
1

i
n
c
h
2010 and 2012 Cover Soil Gradations_mmd.xlsx
1
1
/
2
-
i
n
c
h
3/
4
-
i
n
c
h
1-
i
n
c
h
3/
8
-
i
n
c
h
No
.

4
No
.

1
0
No
.

2
0
No
.
6
0
No
.

1
0
0
No
.
2
0
0
0
20
40
60
80
100
0.00010.0010.010.1110100
Pe
r
c
e
n
t

F
i
n
e
r

(
%
)
Particle Size (mm)
E3-A
E5-B
E8-B
W2-A
W2-B
W5-A
W5-B
W8-A
W8-B
W9-B
E2A-2010
E2B-2010
E4-2010
E5-2010
E6-2010
E7-2010
E8-2010
W1-2010
W2-2010
W7-2010
W9-2010
Group F
(5% of total
cover quantity
available)
Group B
PI = NP -12
(48% of total
cover quantity
available)
Group U
PI = 9-18
(47% of total
cover quantity
available)
Figure 2. White Mesa Cover Borrow Stockpiles Gradations from
2010 and 2012 Laboratory Testing (excluding topsoil samples)
Note: Group B (broadly graded), Group U (uniformly graded), and Group F
(fine textured) based on evaluation of gradations and Benson (2012)*.
*Benson, C., 2012. Electronic communication from Craig Benson, University of Wisconsin-Madison, to Melanie Davis, MWH Americas, Inc., regarding evaluation of gradations performed for potential cover soils for White
Mesa, May 20.

INDEX PROPERTIES OF SOILS FROM BLANDING, UTAH

by

C.H. Benson and X. Wang

Geotechnics Report No. 12-37

Wisconsin Geotechnics Laboratory

University of Wisconsin-Madison
Madison, Wisconsin 53706
USA

20 May 2012

1
1. SCOPE

This report describes results of laboratory tests conducted to determine the specific gravity of
solids, Atterberg Limits, and particle size distribution of twelve (12) soil samples from Blanding,
Utah. The soils were delivered to the Wisconsin Geotechnics Laboratory as disturbed samples
in 20-L buckets (2 buckets per soil).

2. METHODS

The two buckets of soil for each sample were inspected, thoroughly blended by hand, and then
tested to determine the specific gravity of solids, Atterberg Limits, and particle size distribution.
The following ASTM methods were employed on the blended samples:

D 422 Standard Test Method for Particle-Size Analysis of Soils

D 854 Standard Test Methods for Specific Gravity of Soil Solids by Water Pycnometer

D 4318 Standard Test Methods for Liquid Limit, Plastic Limit, and Plasticity Index of
Soils

3. RESULTS

A summary of the index properties is provided in Table 1. The particle size distribution curves
are summarized in Fig. 1. Data recorded from the tests are in the appendix.

Table 1. Summary of index properties for soils from Blanding, Utah.
Sample ID Liquid
Limit
Plastic
Limit
Plasticity
Index
Specific
Gravity
Gravel
(%)
Sand
(%)
Fines
(%)
E1-A 23 18 5 2.61 0 41 59
E3-A 54 24 30 2.53 0 23 77
E5-B 51 24 27 2.56 2 15 83
E8-B 27 16 11 2.63 40 31 29
W2-A 24 14 10 2.62 30 45 25
W4-A 26 19 7 2.60 0 38 62
W2-B 18 13 5 2.63 41 45 14
W5-A 27 18 9 2.61 1 49 50
W5-B 24 15 9 2.63 29 44 27
W8-A 17 NP NP 2.64 35 51 14
W8-B 15 NP NP 2.66 32 40 28
W9-B 28 16 12 2.63 6 44 50

2

Fig. 1. Particle size distribution curves for soils from Blanding, Utah.
0
20
40
60
80
100
0.00010.0010.010.1110100
E1-A
E3-A
E5-B
E8-B
W2-A
W4-A
W2-B
W5-A
W5-B
W8-A
W8-B
W9-B
Pe
r
c
e
n
t

F
i
n
e
r

(
%
)
Particle Size (mm)

3

APPENDIX:

DATA SHEETS

Test No.E1-A E3-A E5-B E8-B W2-A W4-A W2-B W5-A W5-B W8-A W8-B W9-B
Volumetric Flask No.500 500 500 500 500 500 500 500 500 500 500 500
Weight of Flask (g)W1 170.7 170.7 170.7 170.7 170.7 170.7 170.7 170.7 170.7 170.7 170.7 170.7
Dry Soil (g)W2 92.7 127.3 117.6 132.9 131.5 138.9 127.6 124.8 132.3 96.8 116.5 91.6
Weight of Flask + Dry Soil (g)W1 + W2 263.4 298 288.3 303.6 302.2 309.6 298.3 295.5 303 267.5 287.2 262.3
Weight of Flask + Dry Soil + Water (g)W1 + W2 + W3 727.2 747.1 741.7 752.5 751.4 755.6 749.2 747.1 752.1 730.2 742.8 726.8
Temperature T1 23 23 23 23 23 23 23 23 23 23 23 23
Weight of Flask + Water (g)W1 + W4 670 670 670 670 670 670 670 670 670 670 670 670
Temperature T2 23 23 23 23 23 23 23 23 23 23 23 23
Weight of Equal Volume of Water W4 - W3 35.5 50.2 45.9 50.4 50.1 53.3 48.4 47.7 50.2 36.6 43.7 34.8
Gs at Temperature W2 / (W4 - W3)2.611 2.536 2.562 2.637 2.625 2.606 2.636 2.616 2.635 2.645 2.666 2.632
A 0.9982 0.9982 0.9982 0.9982 0.9982 0.9982 0.9982 0.9982 0.9982 0.9982 0.9982 0.9982
Gs at Temperature of 20oC A Gs 2.61 2.53 2.56 2.63 2.62 2.60 2.63 2.61 2.63 2.64 2.66 2.63
Specific Gravity ASTM D854
Wisconsin Geotechnics Laboratory
Group Target Moisture WT of WT of Wet Soil WT of Dry Soil Water Actual Blow Liquid
#N Can Moisture Can + Moisture Can + Moisture Can Content Number Limit
#(G)(g)(g)(%)N
30 - 40 3 23.7 57.2 51.1 22.3 56
20 - 30 1 31.6 63.3 57.3 23.3 24
10 - 20 2 31.4 70.6 63.1 23.7 12
30 - 40 22 31.2 59.5 50.2 48.9 58
20 - 30 7 31.4 73.7 59.1 52.7 30
10 - 20 h 31.7 68.2 55.1 56.0 19
30 - 40 j 31.4 66.4 55 48.3 37
20 - 30 2,4 31.7 70.3 57.1 52.0 24
10 - 20 1 29.6 67.8 54.3 54.7 14
30 - 40 b 31.9 70.2 62.8 23.9 55
20 - 30 5 31.1 78.9 69.1 25.8 30
10 - 20 d1 28.7 78.8 67.6 28.8 14
Group Moisture WT of WT of Wet Soil WT of Dry Soil Water Plastic
#Can Moisture Can + Moisture Can + Moisture Can Content Limit
#(G)(g)(g)(%)
E1-A 1 31.6 40.1 38.8 18.1 18
E3-A 6 31.3 49.4 45.9 24.0 24
E5-B 10 26.5 48.2 44 24.0 24
E8-B 3 28.9 49 46.3 15.5 16
Wisconsin Geotechnics Laboratory
Plastic Limit Test (ASTM D 4318)
23
54
51
27
E1-A
E3-A
E5-B
E8-B
Liquid Limit Test (ASTM D 4318)
48.0
49.0
50.0
51.0
52.0
53.0
54.0
55.0
56.0
57.0
10 100
Wa
t
e
r

C
o
n
t
e
n
t

%

Blow #
E3-A
Group_2
47.0
48.0
49.0
50.0
51.0
52.0
53.0
54.0
55.0
10 100
Wa
t
e
r

C
o
n
t
e
n
t
,

%

Blow #
E5-B
Group_3
23.0
24.0
25.0
26.0
27.0
28.0
29.0
30.0
10 100
Wa
t
e
r

C
o
n
t
e
n
t
,

%

Blow #
E8-B
Group_4
22.0
22.2
22.4
22.6
22.8
23.0
23.2
23.4
23.6
23.8
10 100
Wa
t
e
r

C
o
n
t
e
n
t

%

Blow #
E1-A
Group_1
Group Target Moisture WT of WT of Wet Soil WT of Dry Soil Water Actual Blow Liquid
#N Can Moisture Can + Moisture Can + Moisture Can Content Number Limit
#(G)(g)(g)(%)N
30 - 40 b 31.9 78.4 70.1 21.7 51
20 - 30 5 31.1 83.4 73.4 23.6 23
10 - 20 10 26.5 79.1 68.7 24.6 18
30 - 40 3 28.9 91.5 78.8 25.5 29
20 - 30 9 31.5 84.6 73.4 26.7 21
10 - 20 d 28.7 78.4 67.3 28.8 11
30 - 40 h 31.7 68.1 62.2 19.3 12
20 - 30 j 31.4 85.5 77 18.6 20
10 - 20 7 31.4 88.7 80 17.9 33
30 - 40 1 31.5 81.8 71.8 24.8 45
20 - 30 6 31.3 87.1 75.1 27.4 19
10 - 20 2 31.4 78.5 67.7 29.8 12
Group Moisture WT of WT of Wet Soil WT of Dry Soil Water Plastic
#Can Moisture Can + Moisture Can + Moisture Can Content Limit
#(G)(g)(g)(%)
W2-A 1 29.6 42.3 40.7 14.4 14
W4-A 22 31.2 49.4 46.5 19.0 19
W2-B 3 23.7 37.4 35.8 13.2 13
W5-A 2 31.7 52.5 49.4 17.5 18
Wisconsin Geotechnics Laboratory
Plastic Limit Test (ASTM D 4318)
24
26
18
27
W2-A
W4-A
W2-B
W5-A
Liquid Limit Test (ASTM D 4318)
25.0
25.5
26.0
26.5
27.0
27.5
28.0
28.5
29.0
10 100
Wa
t
e
r

C
o
n
t
e
n
t

%

Blow #
W4-A
Group_6
17.8
18.0
18.2
18.4
18.6
18.8
19.0
19.2
19.4
19.6
10 100
Wa
t
e
r

C
o
n
t
e
n
t
,

%

Blow #
W2-B
Group_7
23.0
24.0
25.0
26.0
27.0
28.0
29.0
30.0
31.0
10 100
Wa
t
e
r

C
o
n
t
e
n
t
,

%

Blow #
W5-A
Group_8
21.5
22.0
22.5
23.0
23.5
24.0
24.5
25.0
10 100
Wa
t
e
r

C
o
n
t
e
n
t

%

Blow #
W2-A
Group_5
Group Target Moisture WT of WT of Wet Soil WT of Dry Soil Water Actual Blow Liquid
#N Can Moisture Can + Moisture Can + Moisture Can Content Number Limit
#(G)(g)(g)(%)N
30 - 40 f1 31.5 68.5 61.7 22.5 56
20 - 30 2 31.7 67.4 60.7 23.1 28
10 - 20 9 31.5 65.2 58.5 24.8 13
30 - 40 6 31.3 70.2 63.7 20.1 15
20 - 30 5 31.1 73.8 66.1 22.0 9
10 - 20 d 28.7 86 74.6 24.8 5
30 - 40 1 31.5 71.7 64.6 21.5 14
20 - 30 2 31.4 73.2 64.8 25.1 6
10 - 20 b 31.9 81.2 75.2 13.9 28
30 - 40 j 31.4 75.8 66.9 25.1 47
20 - 30 1 29.5 85.9 73.6 27.9 21
10 - 20 10 26.5 81.1 68.3 30.6 12
Group Moisture WT of WT of Wet Soil WT of Dry Soil Water Plastic
#Can Moisture Can + Moisture Can + Moisture Can Content Limit
#(G)(g)(g)(%)
9 7 31.3 54.3 51.3 15.0 15
10 NP
11 3 23.7 37.4 35.5 16.1 16
12 h 31.7 52.8 49.9 15.9 16
Wisconsin Geotechnics Laboratory
Plastic Limit Test (ASTM D 4318)
Liquid Limit Test (ASTM D 4318)
9
10
11
12
24
17
15
28
15.0
17.0
19.0
21.0
23.0
25.0
27.0
1 10 100
Wa
t
e
r

C
o
n
t
e
n
t

%

Blow #
W8-A
Group_10
0.0
5.0
10.0
15.0
20.0
25.0
30.0
1 10 100
Wa
t
e
r

C
o
n
t
e
n
t
,

%

Blow #
W8-B
Group_11
23.0
24.0
25.0
26.0
27.0
28.0
29.0
30.0
31.0
32.0
10 100
Wa
t
e
r

C
o
n
t
e
n
t
,

%

Blow #
W9-B
Group_12
22.0
22.5
23.0
23.5
24.0
24.5
25.0
10 100
Wa
t
e
r

C
o
n
t
e
n
t

%

Blow #
W5-B
Group_9
0
10
20
30
40
50
60
70
80
90
100
0.00010.0010.010.1110100
Pe
r
c
e
n
t

F
i
n
e
r

(
%
)

Particle Size (mm)
Mechanical
Sedimentation
E1-A
Sample ID:Test Date:
Weight of Air Dry Sample =791 g Initials:
Sieve No.Sieve
Opening
Weight Retained
on Each Sieve
Percent Retained
on Each Sieve
Cumulative Percent
Retained Percent Finer
(mm)(g)(%)(%)(%)
2"50.8 0.00 0 0 100
1"25.4 0.00 0.00 0.00 100.00
3/4"19.0 0.00 0.00 0.00 100.00
1/2"12.7 0.00 0.00 0.00 100.00
3/8"9.52 0.00 0.00 0.00 100.00
4 4.75 0.51 0.06 0.06 99.94
10 2.00 1.87 0.24 0.30 99.70
20 0.85 1.93 0.24 0.55 99.45
40 0.425 3.79 0.48 1.02 98.98
60 0.250 21.63 2.74 3.76 96.24
100 0.106 44.60 5.64 9.40 90.60
200 0.075 246.73 31.21 40.61 59.39
Pan 469.53 59.39 100.00 0.00
Total Weight (g) =791
Geotechnics Laboratory
E1-A
Mechanical Particle Size Analysis - ASTM D 422
University of Wisconsin-Madison
www.uwgeoengineering.org
Sample ID:Temp. Correction, A 0.0130
Specific Gravity, Gs = 2.61 Hydrometer Type:ASTM 152H
Dry Weight of Soil, W (g) =50 Temperature of Test, C 23
Meniscus Correction, Fm =0.5 Zero Correction, Fz 6
Temperature Correction, FT =0.9 a 1.010
40
98.98
Time Hydrometer Rcp Rcl L D Final Percent Percent
(min)Reading, R (cm)(mm)Finer (%)Finer
0 0.425 98.98
0.3 32 26.90 40.90 11.05 0.086619 53.76 54.32
0.5 30 24.90 38.90 11.38 0.062149 49.77 50.28
1.0 20 14.90 28.90 13.01 0.046998 29.78 30.09
2.0 19 13.90 27.90 13.18 0.033441 27.78 28.07
4.0 17 11.90 25.90 13.50 0.023938 23.78 24.03
8.0 16 10.90 24.90 13.67 0.017029 21.79 22.01
15.0 15.5 10.40 24.40 13.75 0.012473 20.79 21.00
30.0 15 9.90 23.90 13.83 0.008846 19.79 19.99
61.0 14.5 9.40 23.40 13.91 0.006222 18.79 18.98
120.0 14 8.90 22.90 13.99 0.004449 17.79 17.97
240.0 13.5 8.40 22.40 14.08 0.003155 16.79 16.96
1486.0 13 7.90 21.90 14.16 0.001272 15.79 15.95
2921.0 12.5 7.40 21.40 14.24 0.000910 14.79 14.94
Formulas:
FT = -4.85 + 0.25 T a = f(Gs) = 1.65 Gs / (2.65 (Gs - 1))
Rcp = R + FT - FZ Rcl = R + Fm
L = f(R) = 16.3 - 0.1641 Rcl
η = 0.0911 x 10-4 (g-s/cm2) (if T = 25 oC)
Geotechnics Laboratory
University of Wisconsin-Madison
Sedimentation Particle Size Analysis - ASTM D 422
E1-A
Material Max. Size and Percentage (%)
www.uwgeoengineering.org
()()ωγ−
η==1G
30T,GfA
s
s
10050
aRFinerPercentcp=
0
10
20
30
40
50
60
70
80
90
100
0.00010.0010.010.1110100
Pe
r
c
e
n
t

F
i
n
e
r

(
%
)

Particle Size (mm)
E3-A
Mechanical
Sedimentation
Sample ID:Test Date:
Weight of Air Dry Sample =929 g Initials:
Sieve No.Sieve
Opening
Weight Retained
on Each Sieve
Percent Retained
on Each Sieve
Cumulative Percent
Retained Percent Finer
(mm)(g)(%)(%)(%)
2"50.8 0.00 0 0 100
1"25.4 0.00 0.00 0.00 100.00
3/4"19 0.00 0.00 0.00 100.00
1/2"12.7 0.00 0.00 0.00 100.00
3/8"9.52 0.00 0.00 0.00 100.00
4 4.75 4.08 0.44 0.44 99.56
10 2.00 18.60 2.00 2.44 97.56
20 0.85 15.91 1.71 4.16 95.84
40 0.43 10.95 1.18 5.34 94.66
60 0.25 21.46 2.31 7.65 92.35
100 0.11 54.56 5.88 13.52 86.48
200 0.08 90.46 9.74 23.26 76.74
Pan 712.52 76.74 100.00 0.00
Total Weight (g) =929
Geotechnics Laboratory
E3-A
Mechanical Particle Size Analysis - ASTM D 422
University of Wisconsin-Madison
www.uwgeoengineering.org
Sample ID:Temp. Correction, A 0.0129
Specific Gravity, Gs = 2.63 Hydrometer Type:ASTM 152H
Dry Weight of Soil, W (g) =50 Temperature of Test, C 23
Meniscus Correction, Fm =0.5 Zero Correction, Fz 6
Temperature Correction, FT =0.9 a 1.005
200
94.66
Time Hydrometer Rcp Rcl L D Final Percent Percent
(min)Reading, R (cm)(mm)Finer (%)Finer
0 0.425 94.66
0.2 40 34.90 64.90 9.74 0.0808 66.40 70.14
0.5 38 32.90 62.90 10.07 0.0581 62.59 66.12
1.0 37 31.90 61.90 10.23 0.0414 60.69 64.11
2.0 35 29.90 59.90 10.56 0.0298 56.88 60.09
4.0 34 28.90 58.90 10.72 0.0212 54.98 58.08
8.0 33.5 28.40 58.40 10.80 0.0150 54.03 57.07
15.0 33 27.90 57.90 10.89 0.0110 53.08 56.07
30.0 32 26.90 56.90 11.05 0.0079 51.18 54.06
60.0 31 25.90 55.90 11.21 0.0056 49.27 52.05
123.0 30 24.90 54.90 11.38 0.0039 47.37 50.04
240.0 29 23.90 53.90 11.54 0.0028 45.47 48.03
1475.0 25 19.90 49.90 12.19 0.0012 37.86 39.99
2910.0 19 13.90 43.90 13.18 0.0009 26.44 27.93
Formulas:
FT = -4.85 + 0.25 T a = f(Gs) = 1.65 Gs / (2.65 (Gs - 1))
Rcp = R + FT - FZ Rcl = R + Fm
L = f(R) = 16.3 - 0.1641 Rcl
η = 0.0911 x 10-4 (g-s/cm2) (if T = 25 oC)
Geotechnics Laboratory
University of Wisconsin-Madison
Sedimentation Particle Size Analysis - ASTM D 422
E3-A
Material Max. Size and Percentage (%)
www.uwgeoengineering.org
()()()mint
cmLAmmD=()()ωγ−
η==1G
30T,GfA
s
s
10050
aRFinerPercentcp=
0
10
20
30
40
50
60
70
80
90
100
0.00010.0010.010.1110100
Pe
r
c
e
n
t

F
i
n
e
r

(
%
)

Particle Size (mm)
E5-B
Mechanical
Sedimentaion
Sample ID:Test Date:
Weight of Air Dry Sample =890 g Initials:
Sieve No.Sieve Opening Weight Retained
on Each Sieve
Percent Retained
on Each Sieve
Cumulative Percent
Retained Percent Finer
(mm)(g)(%)(%)(%)
2"50.800 0.00 0 0 100
1"25.400 0.00 0.00 0.00 100.00
3/4"19.000 0.00 0.00 0.00 100.00
1/2"12.700 4.48 0.50 0.50 99.50
3/8"9.520 1.70 0.19 0.69 99.31
4 4.750 7.51 0.84 1.54 98.46
10 2.000 11.13 1.25 2.79 97.21
20 0.850 9.82 1.10 3.89 96.11
40 0.425 8.19 0.92 4.81 95.19
60 0.250 16.44 1.85 6.66 93.34
100 0.106 30.31 3.41 10.07 89.93
200 0.075 64.45 7.25 17.32 82.68
Pan 735.52 82.68 100.00 0.00
Total Weight (g) =890
Geotechnics Laboratory
University of Wisconsin-Madison
Mechanical Particle Size Analysis - ASTM D 422
E5-B
www.uwgeoengineering.org
Sample ID:Temp. Correction, A 0.0132
Specific Gravity, Gs = 2.56 Hydrometer Type:ASTM 152H
Dry Weight of Soil, W (g) =50 Temperature of Test, C 23
Meniscus Correction, Fm =0.5 Zero Correction, Fz 6
Temperature Correction, FT =0.9 a 1.022
40
95.19
Time Hydrometer Rcp Rcl L D Final Percent Percent
(min)Reading, R (cm)(mm)Finer (%)Finer
0.0 0.425 95.19
0.2 45 39.90 72.90 8.92 0.0791 77.64 81.57
0.5 43 37.90 70.90 9.25 0.0569 73.75 77.48
1.0 41 35.90 68.90 9.58 0.0410 69.86 73.39
2.0 39.5 34.40 67.40 9.82 0.0293 66.94 70.33
4.0 38.5 33.40 66.40 9.99 0.0209 64.99 68.28
8.0 38 32.90 65.90 10.07 0.0148 64.02 67.26
15.0 37 31.90 64.90 10.23 0.0109 62.07 65.21
31.0 36 30.90 63.90 10.40 0.0077 60.13 63.17
61.0 35 29.90 62.90 10.56 0.0055 58.18 61.13
120.0 33 27.90 60.90 10.89 0.0040 54.29 57.04
243.0 30 24.90 57.90 11.38 0.0029 48.45 50.90
1455.0 26 20.90 53.90 12.03 0.0012 40.67 42.73
2890.0 23 17.90 50.90 12.52 0.0009 34.83 36.59
Formulas:
FT = -4.85 + 0.25 T a = f(Gs) = 1.65 Gs / (2.65 (Gs - 1))
Rcp = R + FT - FZ Rcl = R + Fm
L = f(R) = 16.3 - 0.1641 Rcl
η = 0.0911 x 10-4 (g-s/cm2) (if T = 25 oC)
Geotechnics Laboratory
University of Wisconsin-Madison
Sedimentation Particle Size Analysis - ASTM D 422
E5-B
Material Max. Size and
Percentage (%)
www.uwgeoengineering.org
()()()mint
cmLAmmD=()()ωγ−
η==1G
30T,GfA
s
s
10050
aRFinerPercentcp=
0
10
20
30
40
50
60
70
80
90
100
0.00010.0010.010.1110100
Pe
r
c
e
n
t

F
i
n
e
r

(
%
)

Particle Size (mm)
E8-B
Mechanical
Sedimentation
Sample ID:Test Date:
Weight of Air Dry Sample =1639 g Initials:
Sieve No.Sieve Opening Weight Retained
on Each Sieve
Percent Retained
on Each Sieve
Cumulative
Percent Retained Percent Finer
(mm)(g)(%)(%)(%)
2"50.800 0.00 0 0 100
1"25.400 296.07 18.07 18.07 81.93
3/4"19.000 84.17 5.14 23.20 76.80
1/2"12.700 106.06 6.47 29.68 70.32
3/8"9.520 70.74 4.32 33.99 66.01
4 4.750 98.02 5.98 39.97 60.03
10 2.000 63.00 3.84 43.82 56.18
20 0.850 25.01 1.53 45.34 54.66
40 0.425 34.36 2.10 47.44 52.56
60 0.250 86.55 5.28 52.72 47.28
100 0.106 129.17 7.88 60.60 39.40
200 0.075 173.98 10.62 71.22 28.78
Pan 471.62 28.78 100.00 0.00
Total Weight (g) =1639
Geotechnics Laboratory
University of Wisconsin-Madison
Mechanical Particle Size Analysis - ASTM D 422
E8-B
www.uwgeoengineering.org
Sample ID:Temp. Correction, A 0.0129
Specific Gravity, Gs = 2.63 Hydrometer Type:ASTM 152H
Dry Weight of Soil, W (g) =50 Temperature of Test, C 23
Meniscus Correction, Fm =0.5 Zero Correction, Fz 6
Temperature Correction, FT =0.9 a 1.005
40
52.56
Time Hydrometer Rcp Rcl L D Final Percent Percent
(min)Reading, R (cm)(mm)Finer (%)Finer
0.0 0.425 52.56
0.2 33 27.90 45.40 10.89 0.0854 29.47 56.07
0.5 29 23.90 41.40 11.54 0.0622 25.24 48.03
1.0 25 19.90 37.40 12.19 0.0452 21.02 39.99
2.0 22.5 17.40 34.90 12.60 0.0325 18.38 34.97
4.0 21 15.90 33.40 12.85 0.0232 16.79 31.95
8.0 20 14.90 32.40 13.01 0.0165 15.74 29.94
15.0 19.5 14.40 31.90 13.09 0.0121 15.21 28.94
30.0 19 13.90 31.40 13.18 0.0086 14.68 27.93
60.0 18.5 13.40 30.90 13.26 0.0061 14.15 26.93
120.0 17.5 12.40 29.90 13.42 0.0043 13.10 24.92
242.0 16.5 11.40 28.90 13.58 0.0031 12.04 22.91
1438.0 15 9.90 27.40 13.83 0.0013 10.46 19.90
2873.0 13 7.90 25.40 14.16 0.0009 8.34 15.88
Formulas:
FT = -4.85 + 0.25 T a = f(Gs) = 1.65 Gs / (2.65 (Gs - 1))
Rcp = R + FT - FZ Rcl = R + Fm
L = f(R) = 16.3 - 0.1641 Rcl
η = 0.0911 x 10-4 (g-s/cm2) (if T = 25 oC)
Geotechnics Laboratory
University of Wisconsin-Madison
E8-B
Material Max. Size and
Percentage (%)
Sedimentation Particle Size Analysis - ASTM D 422
www.uwgeoengineering.org
()()()mint
cmLAmmD=()()ωγ−
η==1G
30T,GfA
s
s
10050
aRFinerPercentcp=
0
10
20
30
40
50
60
70
80
90
100
0.00010.0010.010.1110100
Pe
r
c
e
n
t

F
i
n
e
r

(
%
)

Particle Size (mm)
W2-A
Mechanical
Sedimentation
Sample ID:Test Date:
Weight of Air Dry Sample =1766 g Initials:
Sieve No.Sieve Opening Weight Retained
on Each Sieve
Percent Retained on
Each Sieve
Cumulative
Percent Retained Percent Finer
(mm)(g)(%)(%)(%)
2"50.800 0.00 0 0 100
1"25.400 120.36 6.82 6.82 93.18
3/4"19.000 48.06 2.72 9.54 90.46
1/2"12.700 99.19 5.62 15.16 84.84
3/8"9.520 102.84 5.82 20.98 79.02
4 4.750 167.06 9.46 30.44 69.56
10 2.000 177.05 10.03 40.47 59.53
20 0.850 110.90 6.28 46.75 53.25
40 0.425 68.17 3.86 50.61 49.39
60 0.250 104.06 5.89 56.51 43.49
100 0.106 159.98 9.06 65.57 34.43
200 0.075 164.67 9.33 74.89 25.11
Pan 443.32 25.11 100.00 0.00
Total Weight (g) =1766
Geotechnics Laboratory
University of Wisconsin-Madison
Mechanical Particle Size Analysis - ASTM D 422
W2-A
www.uwgeoengineering.org
Sample ID:Temp. Correction, A 0.0130
Specific Gravity, Gs = 2.62 Hydrometer Type:ASTM 152H
Dry Weight of Soil, W (g) =50 Temperature of Test, C 23
Meniscus Correction, Fm =0.5 Zero Correction, Fz 6
Temperature Correction, FT =0.9 a 1.007
40
49.39
Time Hydrometer Rcp Rcl L D Final Percent Percent
(min)Reading, R (cm)(mm)Finer (%)Finer
0.0 0.425 49.39
0.3 31 25.90 43.90 11.21 0.0870 25.77 52.17
0.5 27 21.90 39.90 11.87 0.0633 21.79 44.12
1.0 24 18.90 36.90 12.36 0.0457 18.80 38.07
2.0 22 16.90 34.90 12.69 0.0327 16.81 34.04
4.0 21 15.90 33.90 12.85 0.0233 15.82 32.03
8.0 20.5 15.40 33.40 12.93 0.0165 15.32 31.02
15.0 20 14.90 32.90 13.01 0.0121 14.82 30.02
30.0 19.5 14.40 32.40 13.09 0.0086 14.33 29.01
60.0 19 13.90 31.90 13.18 0.0061 13.83 28.00
120.0 18 12.90 30.90 13.34 0.0043 12.83 25.99
240.0 16 10.90 28.90 13.67 0.0031 10.84 21.96
415.0 15.5 10.40 28.40 13.75 0.0024 10.35 20.95
1465.0 15 9.90 27.90 13.83 0.0013 9.85 19.94
2866.0 14 8.90 26.90 13.99 0.0009 8.85 17.93
0.0 0 -5.10 12.90 16.28 #DIV/0!-5.07 -10.27
0.0 0 -5.10 12.90 16.28 #DIV/0!-5.07 -10.27
Formulas:
FT = -4.85 + 0.25 T a = f(Gs) = 1.65 Gs / (2.65 (Gs - 1))
Rcp = R + FT - FZ Rcl = R + Fm
L = f(R) = 16.3 - 0.1641 Rcl
η = 0.0911 x 10-4 (g-s/cm2) (if T = 25 oC)
Geotechnics Laboratory
University of Wisconsin-Madison
Sedimentation Particle Size Analysis - ASTM D 422
W2-A
Material Max. Size and
Percentage (%)
www.uwgeoengineering.org
()()()mint
cmLAmmD=()()ωγ−
η==1G
30T,GfA
s
s
10050
aRFinerPercentcp=
0
10
20
30
40
50
60
70
80
90
100
0.00010.0010.010.1110100
Pe
r
c
e
n
t

F
i
n
e
r

(
%
)

Particle Size (mm)
W4-A
Mechanical
Sedimentation
Sample ID:Test Date:
Weight of Air Dry Sample =1051 g Initials:
Sieve No.Sieve
Opening
Weight Retained
on Each Sieve
Percent Retained
on Each Sieve
Cumulative
Percent Retained Percent Finer
(mm)(g)(%)(%)(%)
2"50.800 0.00 0 0 100
1"25.400 0.00 0.00 0.00 100.00
3/4"19.000 0.00 0.00 0.00 100.00
1/2"12.700 0.00 0.00 0.00 100.00
3/8"9.520 0.00 0.00 0.00 100.00
4 4.750 1.15 0.11 0.11 99.89
10 2.000 1.75 0.17 0.28 99.72
20 0.850 2.75 0.26 0.54 99.46
40 0.425 7.72 0.73 1.27 98.73
60 0.250 23.69 2.25 3.53 96.47
100 0.106 24.75 2.36 5.88 94.12
200 0.075 342.77 32.62 38.50 61.50
Pan 646.26 61.50 100.00 0.00
Total Weight (g) =1051
Geotechnics Laboratory
University of Wisconsin-Madison
Mechanical Particle Size Analysis - ASTM D 422
W4-A
www.uwgeoengineering.org
Sample ID:Temp. Correction, A 0.0131
Specific Gravity, Gs = 2.6 Hydrometer Type:ASTM 152H
Dry Weight of Soil, W (g) =50 Temperature of Test, C 23
Meniscus Correction, Fm =0.5 Zero Correction, Fz 6
Temperature Correction, FT =0.9 a 1.012
40
98.73
Time Hydrometer Rcp Rcl L D Final Percent Percent
(min)Reading, R (cm)(mm)Finer (%)Finer
0.0 0 0.425 98.73
0.3 35 29.90 44.90 10.56 0.0849 59.75 60.52
0.5 29 23.90 38.90 11.54 0.0628 47.76 48.38
1.0 23 17.90 32.90 12.52 0.0462 35.77 36.23
2.0 19 13.90 28.90 13.18 0.0335 27.78 28.14
4.0 17.5 12.40 27.40 13.42 0.0239 24.78 25.10
8.0 17 11.90 26.90 13.50 0.0170 23.78 24.09
15.0 16.5 11.40 26.40 13.58 0.0124 22.78 23.08
35.0 16 10.90 25.90 13.67 0.0082 21.78 22.06
60.0 16 10.90 25.90 13.67 0.0062 21.78 22.06
120.0 15 9.90 24.90 13.83 0.0044 19.78 20.04
240.0 14.5 9.40 24.40 13.91 0.0031 18.79 19.03
406.0 14 8.90 23.90 13.99 0.0024 17.79 18.02
1455.0 14 8.90 23.90 13.99 0.0013 17.79 18.02
2857.0 14 8.90 23.90 13.99 0.0009 17.79 18.02
Formulas:
FT = -4.85 + 0.25 T a = f(Gs) = 1.65 Gs / (2.65 (Gs - 1))
Rcp = R + FT - FZ Rcl = R + Fm
L = f(R) = 16.3 - 0.1641 Rcl
η = 0.0911 x 10-4 (g-s/cm2) (if T = 25 oC)
Geotechnics Laboratory
University of Wisconsin-Madison
Sedimentation Particle Size Analysis - ASTM D 422
W4-A
Material Max. Size and
Percentage (%)
www.uwgeoengineering.org
()()()mint
cmLAmmD=()()ωγ−
η==1G
30T,GfA
s
s
10050
aRFinerPercentcp=
0
10
20
30
40
50
60
70
80
90
100
0.00010.0010.010.1110100
Pe
r
c
e
n
t

F
i
n
e
r

(
%
)

Particle Size (mm)
W2-B
Mechanical
Sedimentation
Sample ID:Test Date:
Weight of Air Dry Sample =1584 g Initials:
Sieve No.Sieve Opening Weight Retained on
Each Sieve
Percent Retained on
Each Sieve
Cumulative Percent
Retained Percent Finer
(mm)(g)(%)(%)(%)
2"50.800 0.00 0 0 100
1"25.400 222.48 14.04 14.04 85.96
3/4"19.000 65.42 4.13 18.17 81.83
1/2"12.700 126.64 7.99 26.16 73.84
3/8"9.520 86.57 5.46 31.63 68.37
4 4.750 142.35 8.98 40.61 59.39
10 2.000 148.20 9.35 49.96 50.04
20 0.850 83.29 5.26 55.22 44.78
40 0.425 50.76 3.20 58.42 41.58
60 0.250 122.19 7.71 66.14 33.86
100 0.106 193.49 12.21 78.35 21.65
200 0.075 122.12 7.71 86.06 13.94
Pan 220.95 13.94 100.00 0.00
Total Weight (g) =1584
Geotechnics Laboratory
University of Wisconsin-Madison
Mechanical Particle Size Analysis - ASTM D 422
W2-B
www.uwgeoengineering.org
Sample ID:Temp. Correction, A 0.0129
Specific Gravity, Gs = 2.63 Hydrometer Type:ASTM 152H
Dry Weight of Soil, W (g) =50 Temperature of Test, C 23
Meniscus Correction, Fm =0.5 Zero Correction, Fz 6
Temperature Correction, FT =0.9 a 1.005
40
41.58
Time Hydrometer Rcp Rcl L D Final Percent Percent
(min)Reading, R (cm)(mm)Finer (%)Finer
0.0 0 0.425 41.58
0.2 27 21.90 36.40 11.87 0.0892 18.30 44.01
0.5 20 14.90 29.40 13.01 0.0661 12.45 29.94
1.0 19 13.90 28.40 13.18 0.0470 11.61 27.93
2.0 18 12.90 27.40 13.34 0.0334 10.78 25.92
4.0 17 11.90 26.40 13.50 0.0238 9.94 23.91
8.0 16.5 11.40 25.90 13.58 0.0169 9.53 22.91
15.0 16 10.90 25.40 13.67 0.0124 9.11 21.91
30.0 15.5 10.40 24.90 13.75 0.0088 8.69 20.90
60.0 15 9.90 24.40 13.83 0.0062 8.27 19.90
120.0 14.5 9.40 23.90 13.91 0.0044 7.85 18.89
240.0 14 8.90 23.40 13.99 0.0031 7.44 17.89
396.0 13.5 8.40 22.90 14.08 0.0024 7.02 16.88
1446.0 13 7.90 22.40 14.16 0.0013 6.60 15.88
2848.0 12 6.90 21.40 14.32 0.0009 5.77 13.87
0.0 0 -5.10 9.40 16.28 #DIV/0!-4.26 -10.25
0.0 0 -5.10 9.40 16.28 #DIV/0!-4.26 -10.25
Formulas:
FT = -4.85 + 0.25 T a = f(Gs) = 1.65 Gs / (2.65 (Gs - 1))
Rcp = R + FT - FZ Rcl = R + Fm
L = f(R) = 16.3 - 0.1641 Rcl
η = 0.0911 x 10-4 (g-s/cm2) (if T = 25 oC)
Geotechnics Laboratory
University of Wisconsin-Madison
Sedimentation Particle Size Analysis - ASTM D 422
W2-B
Material Max. Size and
Percentage (%)
www.uwgeoengineering.org
()()()mint
cmLAmmD=()()ωγ−
η==1G
30T,GfA
s
s
10050
aRFinerPercentcp=
0
10
20
30
40
50
60
70
80
90
100
0.00010.0010.010.1110100
Pe
r
c
e
n
t

F
i
n
e
r

(
%
)

Particle Size (mm)
W5-A
Mechanical
Sedimentation
Sample ID:Test Date:
Weight of Air Dry Sample =1100 g Initials:
Sieve No.Sieve Opening Weight Retained
on Each Sieve
Percent Retained
on Each Sieve
Cumulative Percent
Retained Percent Finer
(mm)(g)(%)(%)(%)
2"50.800 0.00 0 0 100
1"25.400 0.00 0.00 0.00 100.00
3/4"19.000 0.00 0.00 0.00 100.00
1/2"12.700 0.00 0.00 0.00 100.00
3/8"9.520 4.00 0.36 0.36 99.64
4 4.750 6.16 0.56 0.92 99.08
10 2.000 22.81 2.07 3.00 97.00
20 0.850 21.74 1.98 4.97 95.03
40 0.425 21.89 1.99 6.96 93.04
60 0.250 52.45 4.77 11.73 88.27
100 0.106 54.44 4.95 16.68 83.32
200 0.075 362.25 32.94 49.62 50.38
Pan 554.15 50.38 100.00 0.00
Total Weight (g) =1100
Geotechnics Laboratory
University of Wisconsin-Madison
Mechanical Particle Size Analysis - ASTM D 422
W5-A
www.uwgeoengineering.org
Sample ID:Temp. Correction, A 0.0130
Specific Gravity, Gs = 2.61 Hydrometer Type:ASTM 152H
Dry Weight of Soil, W (g) =50 Temperature of Test, C 23
Meniscus Correction, Fm =0.5 Zero Correction, Fz 6
Temperature Correction, FT =0.9 a 1.010
40
93.04
Time Hydrometer Rcp Rcl L D Final Percent Percent
(min)Reading, R (cm)(mm)Finer (%)Finer
0.0 0 0.425 93.04
0.3 33 27.90 43.90 10.89 0.0860 52.42 56.34
0.5 27 21.90 37.90 11.87 0.0635 41.14 44.22
1.0 22 16.90 32.90 12.69 0.0464 31.75 34.13
2.0 19 13.90 29.90 13.18 0.0334 26.11 28.07
4.0 18 12.90 28.90 13.34 0.0238 24.24 26.05
8.0 17.5 12.40 28.40 13.42 0.0169 23.30 25.04
15.0 17 11.90 27.90 13.50 0.0124 22.36 24.03
30.0 16.5 11.40 27.40 13.58 0.0088 21.42 23.02
60.0 16.5 11.40 27.40 13.58 0.0062 21.42 23.02
120.0 16 10.90 26.90 13.67 0.0044 20.48 22.01
242.0 15.5 10.40 26.40 13.75 0.0031 19.54 21.00
380.0 15 9.90 25.90 13.83 0.0025 18.60 19.99
1430.0 15 9.90 25.90 13.83 0.0013 18.60 19.99
2832.0 15 9.90 25.90 13.83 0.0009 18.60 19.99
0.0 0 -5.10 10.90 16.28 #DIV/0!-9.58 -10.30
0.0 0 -5.10 10.90 16.28 #DIV/0!-9.58 -10.30
Formulas:
FT = -4.85 + 0.25 T a = f(Gs) = 1.65 Gs / (2.65 (Gs - 1))
Rcp = R + FT - FZ Rcl = R + Fm
L = f(R) = 16.3 - 0.1641 Rcl
η = 0.0911 x 10-4 (g-s/cm2) (if T = 25 oC)
Geotechnics Laboratory
University of Wisconsin-Madison
Sedimentation Particle Size Analysis - ASTM D 422
W5-A
Material Max. Size and
Percentage (%)
www.uwgeoengineering.org
()()()mint
cmLAmmD=()()ωγ−
η==1G
30T,GfA
s
s
10050
aRFinerPercentcp=
0
10
20
30
40
50
60
70
80
90
100
0.00010.0010.010.1110100
Pe
r
c
e
n
t

F
i
n
e
r

(
%
)

Particle Size (mm)
W5-B
Mechanical
Sedimentation
Sample ID:Test Date:
Weight of Air Dry Sample =1512 g Initials:
Sieve No.Sieve Opening Weight Retained on
Each Sieve
Percent Retained
on Each Sieve
Cumulative Percent
Retained Percent Finer
(mm)(g)(%)(%)(%)
2"50.8000 0.00 0 0 100
1"25.4000 269.02 17.79 17.79 82.21
3/4"19.0000 10.19 0.67 18.47 81.53
1/2"12.7000 59.39 3.93 22.39 77.61
3/8"9.5200 38.95 2.58 24.97 75.03
4 4.7500 61.39 4.06 29.03 70.97
10 2.0000 61.84 4.09 33.12 66.88
20 0.8500 42.92 2.84 35.96 64.04
40 0.4250 71.73 4.74 40.70 59.30
60 0.2500 204.64 13.53 54.24 45.76
100 0.1060 115.96 7.67 61.91 38.09
200 0.0750 171.25 11.33 73.23 26.77
Pan 404.71 26.77 100.00 0.00
Total Weight (g) =1512
Geotechnics Laboratory
University of Wisconsin-Madison
Mechanical Particle Size Analysis - ASTM D 422
W5-B
www.uwgeoengineering.org
Sample ID:Temp. Correction, A 0.0129
Specific Gravity, Gs = 2.63 Hydrometer Type:ASTM 152H
Dry Weight of Soil, W (g) =50 Temperature of Test, C 23
Meniscus Correction, Fm =0.5 Zero Correction, Fz 6
Temperature Correction, FT =0.9 a 1.005
40
59.30
Time Hydrometer Rcp Rcl L D Final Percent Percent
(min)Reading, R (cm)(mm)Finer (%)Finer
0.0 0 0.425 59.30
0.2 31 25.90 40.90 11.21 0.0867 30.86 52.05
0.5 25 19.90 34.90 12.19 0.0639 23.71 39.99
1.0 21 15.90 30.90 12.85 0.0464 18.95 31.95
2.0 19 13.90 28.90 13.18 0.0332 16.56 27.93
4.0 18 12.90 27.90 13.34 0.0236 15.37 25.92
8.0 17 11.90 26.90 13.50 0.0168 14.18 23.91
15.0 16.5 11.40 26.40 13.58 0.0123 13.58 22.91
30.0 16 10.90 25.90 13.67 0.0087 12.99 21.91
60.0 15.5 10.40 25.40 13.75 0.0062 12.39 20.90
120.0 15 9.90 24.90 13.83 0.0044 11.80 19.90
240.0 14 8.90 23.90 13.99 0.0031 10.61 17.89
429.0 13 7.90 22.90 14.16 0.0024 9.41 15.88
1209.0 12 6.90 21.90 14.32 0.0014 8.22 13.87
2128.0 12 6.90 21.90 14.32 0.0011 8.22 13.87
4683.0 11 5.90 20.90 14.48 0.0007 7.03 11.86
0.0 0 -5.10 9.90 16.28 #DIV/0!-6.08 -10.25
Formulas:
FT = -4.85 + 0.25 T a = f(Gs) = 1.65 Gs / (2.65 (Gs - 1))
Rcp = R + FT - FZ Rcl = R + Fm
L = f(R) = 16.3 - 0.1641 Rcl
η = 0.0911 x 10-4 (g-s/cm2) (if T = 25 oC)
Geotechnics Laboratory
University of Wisconsin-Madison
Sedimentation Particle Size Analysis - ASTM D 422
W5-B
Material Max. Size and
Percentage (%)
www.uwgeoengineering.org
()()()mint
cmLAmmD=()()ωγ−
η==1G
30T,GfA
s
s
10050
aRFinerPercentcp=
0
10
20
30
40
50
60
70
80
90
100
0.00010.0010.010.1110100
Pe
r
c
e
n
t

F
i
n
e
r

(
%
)

Particle Size (mm)
W8-A
Mechanical
Sedimentation
Sample ID:Test Date:
Weight of Air Dry Sample =1354 g Initials:
Sieve No.Sieve Opening Weight Retained
on Each Sieve
Percent Retained
on Each Sieve
Cumulative Percent
Retained Percent Finer
(mm)(g)(%)(%)(%)
2"50.800 0.00 0 0 100
1"25.400 200.78 14.83 14.83 85.17
3/4"19.000 72.08 5.32 20.15 79.85
1/2"12.700 68.48 5.06 25.20 74.80
3/8"9.520 49.77 3.67 28.88 71.12
4 4.750 78.25 5.78 34.66 65.34
10 2.000 79.27 5.85 40.51 59.49
20 0.850 52.87 3.90 44.41 55.59
40 0.425 89.60 6.62 51.03 48.97
60 0.250 203.74 15.04 66.07 33.93
100 0.106 186.92 13.80 79.88 20.12
200 0.075 85.98 6.35 86.22 13.78
Pan 186.57 13.78 100.00 0.00
Total Weight (g) =1354
Geotechnics Laboratory
University of Wisconsin-Madison
Mechanical Particle Size Analysis - ASTM D 422
W8-A
www.uwgeoengineering.org
Sample ID:Temp. Correction, A 0.0129
Specific Gravity, Gs = 2.64 Hydrometer Type:ASTM 152H
Dry Weight of Soil, W (g) =50 Temperature of Test, C 23
Meniscus Correction, Fm =0.5 Zero Correction, Fz 6
Temperature Correction, FT =0.9 a 1.002
40
48.97
Time Hydrometer Rcp Rcl L D Final Percent Percent
(min)Reading, R (cm)(mm)Finer (%)Finer
0.0 0 0.425 48.97
0.3 20 14.90 26.90 13.01 0.0931 14.63 29.87
0.5 18 12.90 24.90 13.34 0.0667 12.67 25.86
1.0 16 10.90 22.90 13.67 0.0477 10.70 21.85
2.0 15 9.90 21.90 13.83 0.0339 9.72 19.85
4.0 14 8.90 20.90 13.99 0.0241 8.74 17.84
8.0 14 8.90 20.90 13.99 0.0171 8.74 17.84
15.0 13.5 8.40 20.40 14.08 0.0125 8.25 16.84
30.0 13.5 8.40 20.40 14.08 0.0088 8.25 16.84
61.0 13 7.90 19.90 14.16 0.0062 7.76 15.84
120.0 12 6.90 18.90 14.32 0.0045 6.77 13.83
230.0 12 6.90 18.90 14.32 0.0032 6.77 13.83
419.0 11 5.90 17.90 14.48 0.0024 5.79 11.83
1200.0 11 5.90 17.90 14.48 0.0014 5.79 11.83
2118.0 10 4.90 16.90 14.65 0.0011 4.81 9.82
4673.0 9.5 4.40 16.40 14.73 0.0007 4.32 8.82
-59096737.0 0 -5.10 6.90 16.28 #NUM!-5.01 -10.22
Formulas:
FT = -4.85 + 0.25 T a = f(Gs) = 1.65 Gs / (2.65 (Gs - 1))
Rcp = R + FT - FZ Rcl = R + Fm
L = f(R) = 16.3 - 0.1641 Rcl
η = 0.0911 x 10-4 (g-s/cm2) (if T = 25 oC)
Geotechnics Laboratory
University of Wisconsin-Madison
Sedimentation Particle Size Analysis - ASTM D 422
W8-A
Material Max. Size and
Percentage (%)
www.uwgeoengineering.org
()()()mint
cmLAmmD=()()ωγ−
η==1G
30T,GfA
s
s
10050
aRFinerPercentcp=
0
10
20
30
40
50
60
70
80
90
100
0.00010.0010.010.1110100
Pe
r
c
e
n
t

F
i
n
e
r

(
%
)

Particle Size (mm)
W8-B
Mechanical
Sedimentation
Sample ID:Test Date:
Weight of Air Dry Sample =1016 g Initials:
Sieve No.Sieve Opening Weight Retained
on Each Sieve
Percent Retained
on Each Sieve
Cumulative
Percent Retained Percent Finer
(mm)(g)(%)(%)(%)
2"50.8 0.00 0 0 100
1"25.4 249.88 24.59 24.59 75.41
3/4"19.0 0.00 0.00 24.59 75.41
1/2"12.7 48.98 4.82 29.41 70.59
3/8"9.52 7.89 0.78 30.19 69.81
4 4.75 14.19 1.40 31.59 68.41
10 2.00 24.17 2.38 33.96 66.04
20 0.85 23.12 2.28 36.24 63.76
40 0.425 52.87 5.20 41.44 58.56
60 0.250 114.81 11.30 52.74 47.26
100 0.106 74.36 7.32 60.06 39.94
200 0.075 119.61 11.77 71.83 28.17
Pan 286.23 28.17 100.00 0.00
Total Weight (g) =1016
Geotechnics Laboratory
University of Wisconsin-Madison
Mechanical Particle Size Analysis - ASTM D 422
W8-B
www.uwgeoengineering.org
Sample ID:Temp. Correction, A 0.0128
Specific Gravity, Gs = 2.66 Hydrometer Type:ASTM 152H
Dry Weight of Soil, W (g) =50 Temperature of Test, C 23
Meniscus Correction, Fm =0.5 Zero Correction, Fz 6
Temperature Correction, FT =0.9 a 0.998
40
58.56
Time Hydrometer Rcp Rcl L D Final Percent Percent
(min)Reading, R (cm)(mm)Finer (%)Finer
0.0 0 0.425 58.56
0.2 30 24.90 39.90 11.38 0.0866 29.10 49.69
0.5 25 19.90 34.90 12.19 0.0634 23.25 39.71
1.0 21 15.90 30.90 12.85 0.0460 18.58 31.73
2.0 19 13.90 28.90 13.18 0.0329 16.24 27.74
4.0 17 11.90 26.90 13.50 0.0236 13.91 23.75
8.0 16.5 11.40 26.40 13.58 0.0167 13.32 22.75
15.0 16 10.90 25.90 13.67 0.0122 12.74 21.75
30.0 16 10.90 25.90 13.67 0.0087 12.74 21.75
60.0 15 9.90 24.90 13.83 0.0062 11.57 19.76
120.0 15 9.90 24.90 13.83 0.0044 11.57 19.76
220.0 14 8.90 23.90 13.99 0.0032 10.40 17.76
408.0 13.5 8.40 23.40 14.08 0.0024 9.82 16.76
1189.0 13.5 8.40 23.40 14.08 0.0014 9.82 16.76
2107.0 12.5 7.40 22.40 14.24 0.0011 8.65 14.77
4662.0 11.5 6.40 21.40 14.40 0.0007 7.48 12.77
-59096748.0 0 -5.10 9.90 16.28 #NUM!-5.96 -10.18
Formulas:
FT = -4.85 + 0.25 T a = f(Gs) = 1.65 Gs / (2.65 (Gs - 1))
Rcp = R + FT - FZ Rcl = R + Fm
L = f(R) = 16.3 - 0.1641 Rcl
η = 0.0911 x 10-4 (g-s/cm2) (if T = 25 oC)
Geotechnics Laboratory
University of Wisconsin-Madison
Sedimentation Particle Size Analysis - ASTM D 422
W8-B
Material Max. Size and
Percentage (%)
www.uwgeoengineering.org
()()()mint
cmLAmmD=()()ωγ−
η==1G
30T,GfA
s
s
10050
aRFinerPercentcp=
0
10
20
30
40
50
60
70
80
90
100
0.00010.0010.010.1110100
Pe
r
c
e
n
t

F
i
n
e
r

(
%
)

Particle Size (mm)
W9-B
Mechanical
Sedimentation
Sample ID:Test Date:
Weight of Air Dry Sample =1027 g Initials:
Sieve No.Sieve Opening Weight Retained on
Each Sieve
Percent Retained
on Each Sieve
Cumulative Percent
Retained Percent Finer
(mm)(g)(%)(%)(%)
2"50.8 0.00 0 0 100
1"25.4 0.00 0.00 0.00 100
3/4"19.0 11.91 1.16 1.16 98.84
1/2"12.7 0.00 0.00 1.16 98.84
3/8"9.52 12.33 1.20 2.36 97.64
4 4.75 36.00 3.51 5.87 94.13
10 2.00 46.08 4.49 10.35 89.65
20 0.85 33.14 3.23 13.58 86.42
40 0.425 23.26 2.26 15.84 84.16
60 0.250 36.69 3.57 19.42 80.58
100 0.106 51.93 5.06 24.47 75.53
200 0.075 261.16 25.43 49.90 50.10
Pan 514.52 50.10 100.00 0.00
Total Weight (g) =1027
Wisconsin Geotechnics Laboratory
Mechanical Particle Size Analysis - ASTM D 422
W9-B
Sample ID:Temp. Correction, A 0.0129
Specific Gravity, Gs = 2.63 Hydrometer Type:ASTM 152H
Dry Weight of Soil, W (g) =50 Temperature of Test, C 23
Meniscus Correction, Fm =0.5 Zero Correction, Fz 6
Temperature Correction, FT =0.9 a 1.005
40
84.16
Time Hydrometer Rcp Rcl L D Final Percent Percent
(min)Reading, R (cm)(mm)Finer (%)Finer
0.0 0 0.425 84.16
0.2 40 34.90 50.90 9.74 0.0808 59.02 70.14
0.5 31 25.90 41.90 11.21 0.0613 43.80 52.05
1.0 25 19.90 35.90 12.19 0.0452 33.66 39.99
2.0 21 15.90 31.90 12.85 0.0328 26.89 31.95
4.0 19 13.90 29.90 13.18 0.0235 23.51 27.93
8.0 18.5 13.40 29.40 13.26 0.0167 22.66 26.93
15.0 18 12.90 28.90 13.34 0.0122 21.82 25.92
30.0 18 12.90 28.90 13.34 0.0086 21.82 25.92
64.0 17 11.90 27.90 13.50 0.0059 20.13 23.91
126.0 16 10.90 26.90 13.67 0.0043 18.43 21.91
201.0 16 10.90 26.90 13.67 0.0034 18.43 21.91
388.0 15.5 10.40 26.40 13.75 0.0024 17.59 20.90
1169.0 15.5 10.40 26.40 13.75 0.0014 17.59 20.90
2088.0 14 8.90 24.90 13.99 0.0011 15.05 17.89
4642.0 13 7.90 23.90 14.16 0.0007 13.36 15.88
-59096768.0 0 -5.10 10.90 16.28 #NUM!-8.63 -10.25
Formulas:
FT = -4.85 + 0.25 T a = f(Gs) = 1.65 Gs / (2.65 (Gs - 1))
Rcp = R + FT - FZ Rcl = R + Fm
L = f(R) = 16.3 - 0.1641 Rcl
η = 0.0911 x 10-4 (g-s/cm2) (if T = 25 oC)
Wisconsin Geotechnics Laboratory
Sedimentation Particle Size Analysis - ASTM D 422
W9-B
Material Max. Size and
Percentage (%)
()()()mint
cmLAmmD=()()ωγ−
η==1G
30T,GfA
s
s
10050
aRFinerPercentcp=

COMPACTION AND HYDRAULIC PROPERTIES OF SOILS FROM
BLANDING, UTAH

by

C.H. Benson and X. Wang

Geotechnics Report No. 12-41

Wisconsin Geotechnics Laboratory

University of Wisconsin-Madison
Madison, Wisconsin 53706
USA

24 July 2012

1
1. SCOPE

This report describes results of laboratory tests to determine the compaction and hydraulic
properties of soil samples from Blanding, Utah. The soils were delivered to the Wisconsin
Geotechnics Laboratory as disturbed samples in 20-L buckets (2 buckets per soil). Index
properties of the soils were determined previously and are reported in Geotechnics Report No.
12-37.

2. METHODS

The same soil samples used for index properties testing were used for the tests conducted in
this study. Tests were conducted to determine standard Proctor compaction curves, saturated
hydraulic conductivity, soil water characteristic curves (SWCCs), and 1.5 MPa moisture content.
The following ASTM methods were employed:

D 698 Standard Test Methods for Laboratory Compaction Characteristics of Soil Using
Standard Effort (12 400 ft-lbf/ft (600 kN-m/m))

D 5084 Standard Test Methods for Measurement of Hydraulic Conductivity of Saturated
Porous Materials Using a Flexible Wall Permeameter

D 6836 Standard Test Methods for Determination of the Soil Water Characteristic Curve for
Desorption Using Hanging Column, Pressure Extractor, Chilled Mirror Hygrometer, or
Centrifuge

Test specimens for the saturated hydraulic conductivity, SWCC, and 1.5 MPa moisture content
tests were prepared at 85% of maximum dry unit weight and optimum water content per
standard Proctor, as specified by the requestor.

Saturated hydraulic conductivity of each test specimen was measured in a flexible-wall
permeameter following the methods in ASTM D 5084. The backpressure was set at 30 psi and
the hydraulic gradient was 10. The effective stress was set at 5.0 psi to simulate the low state
of stress in a cover while ensuring good contact between the membrane and the test specimen.

The wet end of the SWCC was measured following the procedures in ASTM D 6836 using a
hanging column (Method A) or a pressure plate extractor (Method B). A chilled mirror
hygrometer (Method D) was used to complete the dry end of the SWCC after the hanging
column test or pressure plate test was complete. SWCCs were prepared by combining data
from the pressure plate and chilled mirror hygrometer tests as described in D 6836. van
Genuchten’s equation was fit to the SWCC data:

θ−θr
θs −θr
=1
1+(αψ)n
⎡
⎣⎢⎤
⎦⎥
m
(1)

2

where θ is volumetric water content, θr is residual water content, θs is saturated volumetric water
content, ψ is matric suction, and α, m, and n are fitting parameters. Equation 1 was fit to the
data using a non-linear least-squares optimization procedure with the constraint m = 1-n-1.

Moisture contents at 1.5 MPa were determined using the procedures in Method D of ASTM D
6836. Test specimens were prepared at three moisture contents bracketing a suction of 1.5
MPa. Moisture content was then regressed on suction, and the moisture content at 1.5 MPa
was determined from the regression equation.

3. RESULTS

Optimum water contents and maximum dry unit weights from the compaction tests are
summarized in Table 1. Saturated hydraulic conductivities and van Genuchten parameters for
the SWCCs are summarized in Table 2. Gravimetric moisture contents at 1.5 MPa are
summarized in Table 3. Data recorded from the tests are in the appendix.

3

Table 1. Summary of index properties for soils from Blanding, Utah.
Sample ID Optimum Water
Content (%)
Maximum Dry Unit
Weight (pcf)
E1-A1/2 Composite 11.0 118
E3-A1/2 Composite 19.0 105
E8-B1/2 Composite 10.5 125
W2-B1/2 Composite 8.5 128
W5-B1/2 Composite 10.0 122
W8-A1/2 Composite 13.0 117
W9-B1/2 Composite 14.0 115

Table 2. Summary of saturated hydraulic conductivities and van Genuchten Parameters
Sample ID
Sat. Hydraulic
Conductivity
(cm/s)
Saturated Vol.
Water Content
(s)
Residual Vol.
Water Content
(r)

(1/kPa) n
E1-A1/2
Composite 1.3x10-4 0.38 0.024 0.0797 1.35
E3-A1/2
Composite 9.5x10-5 0.44 0.00 0.0787 1.19
W2-B1/2
Composite 1.5x10-3 0.32 0.00 0.2160 1.32
W5-B1/2
Composite 1.1x10-3 0.36 0.00 0.1180 1.35
W8-A1/2
Composite 1.2x10-3 0.37 0.00 0.1840 1.35
W9-B1/2
Composite 4.1x10-4 0.40 0.00 0.0729 1.26

Table 3. Summary of 1.5 MPa gravimetric moisture contents.
Sample ID Gravimetric Water Content (%)
E8-B1/2 Composite 6.0
W2-A1/2 Composite 6.9
W5-A1/2 Composite 7.0
W8-B1/2 Composite 6.4

4

APPENDIX:

DATA SHEETS

Sample I.D.E1_(A1/A2)Test Date
Procedure A Volume of Mold (ft3)0.033
Weight of Hammer (lb)5.5 Hammer Drop (in)12
No. of Blows per Layer 25 No. of Layers 3
WT of Mold
WT of Mold +
Wet Soil
WT of Wet
Soil
Wet Unit
Weight
Water
Content
Dry Unit
Weight
(lb)(lb)(lb)(pcf)(%)(pcf)
9.48 13.05 3.57 107.13 3.6 103.38
9.48 13.45 3.97 119.09 7.6 110.65
9.48 13.86 4.38 131.44 11.0 118.40
9.48 13.81 4.33 129.94 13.6 114.37
9.48 13.47 3.99 119.56 19.7 99.87
#1 #2 #3 #4 #5
T2 M7 14 T4 B3
30.8 24.4 30.7 24.6 25.3
201.8 135.8 153.7 173.2 175.9
195.8 127.9 141.5 155.4 151.1
3.6 7.6 11.0 13.6 19.7
WT of Can + Dry Soil (g)
Water Content (%)
6/8/2012
Test No.
1
2
3
STANDARD PROCTOR COMPACTION TEST
(ASTM D 698)
WT of Can + Wet Soil (g)
Wisconsin Geotechnics Laboratory
4
5
Test No
Can No.
WT of Can (g)
Sample I.D.E3_(A1/A2)Test Date
Procedure A Volume of Mold (ft3)0.033
Weight of Hammer (lb)5.5 Hammer Drop (in)12
No. of Blows per Layer 25 No. of Layers 3
WT of Mold WT of Mold +
Wet Soil
WT of Wet
Soil
Wet Unit
Weight
Water
Content
Dry Unit
Weight
(lb)(lb)(lb)(pcf)(%)(pcf)
9.48 13.27 3.79 113.56 14.2 99.45
9.48 13.59 4.11 123.19 17.8 104.56
9.48 13.67 4.19 125.74 21.2 103.76
9.48 13.56 4.08 122.43 23.7 98.95
9.48 13.44 3.96 118.87 26.9 93.64
#1 #2 #3 #4 #5
SL 7 W3 62 A3
31.8 24.7 24.6 31.2 25.1
172.6 147 143 163.1 162.2
155.1 128.5 122.3 137.8 133.1
14.2 17.8 21.2 23.7 26.9
WT of Can (g)
WT of Can + Wet Soil (g)
WT of Can + Dry Soil (g)
Water Content (%)
2
3
4
5
Test No
Can No.
Wisconsin Geotechnics Laboratory
STANDARD PROCTOR COMPACTION TEST
(ASTM D 698)
6/8/2012
Test No.
1
Sample I.D.E8_(B1/B2)Test Date
Procedure C Volume of Mold (ft3)0.075
Weight of Hammer (lb)5.5 Hammer Drop (in)12
No. of Blows per Layer 56 No. of Layers 3
WT of Mold WT of Mold +
Wet Soil
WT of Wet
Soil
Wet Unit
Weight
Water
Content
Dry Unit
Weight
(lb)(lb)(lb)(pcf)(%)(pcf)
14.20 24.23 10.03 133.67 8.7 122.98
14.20 24.54 10.34 137.93 10.5 124.82
14.20 24.44 10.24 136.59 12.2 121.75
14.20 24.25 10.05 134.03 13.8 117.81
0.00 0.00 #DIV/0!#DIV/0!
#1 #2 #3 #4 #5
J4 EA TR3L 2 - 4
24.9 31.2 24.6 30.9
176.2 160.6 166.3 159.8
164.1 148.3 150.9 144.2
8.7 10.5 12.2 13.8 #DIV/0!
WT of Can (g)
WT of Can + Wet Soil (g)
WT of Can + Dry Soil (g)
Water Content (%)
2
3
4
5
Test No
Can No.
Wisconsin Geotechnics Laboratory
STANDARD PROCTOR COMPACTION TEST
(ASTM D 698)
6/10/2012
Test No.
1
Sample I.D.W2_(B1/B2)Test Date
Procedure C Volume of Mold (ft3)0.075
Weight of Hammer (lb)5.5 Hammer Drop (in)12
No. of Blows per Layer 56 No. of Layers 3
WT of Mold
WT of Mold +
Wet Soil
WT of Wet
Soil
Wet Unit
Weight
Water
Content
Dry Unit
Weight
(lb)(lb)(lb)(pcf)(%)(pcf)
14.20 23.93 9.73 129.71 6.0 122.41
14.20 24.54 10.34 137.82 8.1 127.48
14.20 24.60 10.40 138.69 9.3 126.88
14.20 24.42 10.22 136.28 11.0 122.73
0 0 #DIV/0!#DIV/0!
#1 #2 #3 #4 #5
T4 28 14 3
24.5 24.5 30.6 31.1
189.8 175.1 212.6 216.2
180.5 163.8 197.1 197.8
6.0 8.1 9.3 11.0 #DIV/0!
WT of Can (g)
WT of Can + Wet Soil (g)
WT of Can + Dry Soil (g)
Water Content (%)
2
3
4
5
Test No
Can No.
Wisconsin Geotechnics Laboratory
STANDARD PROCTOR COMPACTION TEST
(ASTM D 698)
6/10/2012
Test No.
1
Sample I.D.W5_(B1/B2)Test Date
Procedure C Volume of Mold (ft3)0.075
Weight of Hammer (lb)5.5 Hammer Drop (in)12
No. of Blows per Layer 56 No. of Layers 3
WT of Mold
WT of Mold +
Wet Soil
WT of Wet
Soil
Wet Unit
Weight
Water
Content
Dry Unit
Weight
(lb)(lb)(lb)(pcf)(%)(pcf)
14.20 23.26 9.06 120.85 5.5 114.51
14.20 23.60 9.40 125.28 6.9 117.22
14.20 24.27 10.07 134.21 10.1 121.91
14.20 24.28 10.08 134.39 11.9 120.14
14.20 24.02 9.82 130.90 15.1 113.70
#1 #2 #3 #4 #5
21 Y1 5 W3 29
31.1 30.9 24.3 24.7 30.7
196.9 208.1 164 171.8 184.4
188.2 196.7 151.2 156.2 164.2
5.5 6.9 10.1 11.9 15.1
WT of Can (g)
WT of Can + Wet Soil (g)
WT of Can + Dry Soil (g)
Water Content (%)
2
3
4
5
Test No
Can No.
Wisconsin Geotechnics Laboratory
STANDARD PROCTOR COMPACTION TEST
(ASTM D 698)
6/10/2012
Test No.
1
Sample I.D.W8_(A1/A2)Test Date
Procedure C Volume of Mold (ft3)0.075
Weight of Hammer (lb)5.5 Hammer Drop (in)12
No. of Blows per Layer 56 No. of Layers 3
WT of Mold
WT of Mold +
Wet Soil
WT of Wet
Soil
Wet Unit
Weight
Water
Content
Dry Unit
Weight
(lb)(lb)(lb)(pcf)(%)(pcf)
14.20 22.99 8.79 117.16 6.7 109.79
14.20 23.55 9.35 124.72 9.5 113.90
14.20 23.95 9.75 130.00 11.3 116.81
14.20 24.13 9.93 132.43 14.4 115.80
14.20 23.74 9.54 127.15 16.7 108.97
#1 #2 #3 #4 #5
W81 B 29 2-4 J4
24.7 30.9 30.7 30.9 24.9
185.3 175 174.6 179.8 186.5
175.2 162.5 160 161.1 163.4
6.7 9.5 11.3 14.4 16.7
WT of Can (g)
WT of Can + Wet Soil (g)
WT of Can + Dry Soil (g)
Water Content (%)
2
3
4
5
Test No
Can No.
Wisconsin Geotechnics Laboratory
STANDARD PROCTOR COMPACTION TEST
(ASTM D 698)
6/9/2012
Test No.
1
Sample I.D.W9_(B1/B2)Test Date
Procedure A Volume of Mold (ft3)0.033
Weight of Hammer (lb)5.5 Hammer Drop (in)12
No. of Blows per Layer 25 No. of Layers 3
WT of Mold
WT of Mold +
Wet Soil
WT of Wet
Soil
Wet Unit
Weight
Water
Content
Dry Unit
Weight
(lb)(lb)(lb)(pcf)(%)(pcf)
9.47 13.00 3.53 105.85 4.5 101.25
9.47 13.27 3.80 113.92 7.6 105.89
9.47 13.62 4.15 124.64 10.8 112.49
9.47 13.81 4.34 130.28 14.6 113.65
9.47 13.59 4.12 123.72 18.1 104.76
#1 #2 #3 #4 #5
B26 SL 7 X2 R17-3
30.8 31.8 24.7 30.8 30.8
201.1 187.8 161.1 185.1 169.1
193.7 176.8 147.8 165.4 147.9
4.5 7.6 10.8 14.6 18.1
WT of Can (g)
WT of Can + Wet Soil (g)
WT of Can + Dry Soil (g)
Water Content (%)
2
3
4
5
Test No
Can No.
Wisconsin Geotechnics Laboratory
STANDARD PROCTOR COMPACTION TEST
(ASTM D 698)
6/10/2012
Test No.
1
80.00
90.00
100.00
110.00
120.00
130.00
140.00
0.0 5.0 10.0 15.0 20.0 25.0 30.0
Dr
y

U
n
i
t

W
e
i
g
h
t

(
p
c
f
)

Water Contentn(%)
E1
E3
E8
W2
W5
W8
W9
Test Date :
Cell Pressure =35.8 psi Diameter of Sample, D = 15.2 cm
Inflow Pressure = 31.6 psi Length of Sample, L = 11.6 cm
Outflow Pressre =30.0 psi Area of Sample, A = 182.41 cm2
Pressure Difference =1.6 psi Sample Volume, V =2123.9 cm3
Effective Stress = 5.0 psi ain = 5 cm2
Hydraulic Gradient, i =10 aout = 5 cm2
Weight of wet sample =3787.6 (g)Sample Water Content =11.0 (%)
Wet Density =1.8 g/cm3 Dry Density =1.61 g/cm3
Can #WT of Can WT of Can
+ Wet Soil
WT of Can +
Dry Soil
Water
Content
(g)(g)(g)(%)
11.00
Date, Time Inflow OutFlow ∆t H Time K Qout / Qin Qin Qout
(sec)(cm)(min)(cm/sec)
8:23:00 4.8 20.5 0.0 15.7 0.0
8:25:00 11.0 14.5 120.0 3.5 2.0 1.33E-04 1.0 31 30
8:26:00 14.0 11.5 60.0 -2.5 3.0 1.41E-04 1.0 15 15
8:27:00 16.6 9.1 60.0 -7.5 4.0 1.24E-04 0.9 13 12
8:28:00 19.0 7.0 60.0 -12.0 5.0 1.16E-04 0.9 12 10.5
8:29:00 21.2 4.6 60.0 -16.6 6.0 1.25E-04 1.1 11 12
8:30:00 23.4 2.7 60.0 -20.7 7.0 1.16E-04 0.9 11 9.5
8:32:00 0.0 24.7 120.0 24.7 9.0
8:33:00 3.8 21.0 60.0 17.2 10.0 1.49E-04 1.0 19 18.5
8:34:00 7.3 17.5 60.0 10.2 11.0 1.48E-04 1.0 17.5 17.5
8:35:00 10.5 14.5 60.0 4.0 12.0 1.38E-04 0.9 16 15
8:36:00 13.5 12.0 60.0 -1.5 13.0 1.29E-04 0.8 15 12.5
8:37:00 16.0 9.2 60.0 -6.8 14.0 1.30E-04 1.1 12.5 14
8:38:00 18.8 6.8 60.0 -12.0 15.0 1.34E-04 0.9 14 12
8:39:00 21.0 4.6 60.0 -16.4 16.0 1.19E-04 1.0 11 11
8:40:00 23.2 2.6 60.0 -20.6 17.0 1.19E-04 0.9 11 10
8:42:00 0.0 24.0 120.0 24.0 19.0
8:43:00 4.0 20.0 60.0 16.0 20.0 1.61E-04 1.0 20 20
8:44:00 7.5 16.8 60.0 9.3 21.0 1.42E-04 0.9 17.5 16
8:45:00 10.8 13.8 60.0 3.0 22.0 1.41E-04 0.9 16.5 15
8:46:00 13.7 11.0 60.0 -2.7 23.0 1.35E-04 1.0 14.5 14
8:47:00 16.4 8.4 60.0 -8.0 24.0 1.32E-04 1.0 13.5 13
8:48:00 19.0 6.0 60.0 -13.0 25.0 1.30E-04 0.9 13 12
8:49:00 21.3 3.8 60.0 -17.5 26.0 1.23E-04 1.0 11.5 11
8:50:00 23.6 1.6 60.0 -22.0 27.0 1.29E-04 1.0 11.5 11
K (cm/s) =1.3E-04
Wisconsin Geotechnics Laboratory
Hydraulic Conductivity Test
ASTM D 5084
7/17/12E1_(A1/A2)Sample I.D.
( )
( )
( )

∆
∆
∆+=
2
1
*
*
H
HLntA
L
aa
aaK
outin
outin
s
Test Date :
Cell Pressure =35.8 psi Diameter of Sample, D = 15.2 cm
Inflow Pressure = 31.6 psi Length of Sample, L = 11.6 cm
Outflow Pressre =30.0 psi Area of Sample, A = 182.41 cm2
Pressure Difference =1.6 psi Sample Volume, V =2123.9 cm3
Effective Stress = 5.0 psi ain = 5 cm2
Hydraulic Gradient, i =10 aout = 5 cm2
Weight of wet sample =3615.2 (g)Sample Water Content =19.0 (%)
Wet Density =1.7 g/cm3 Dry Density =1.43 g/cm3
Can #WT of Can WT of Can
+ Wet Soil
WT of Can +
Dry Soil
Water
Content
(g)(g)(g)(%)
19.00
Date, Time Inflow OutFlow ∆t H Time K Qout / Qin Qin Qout
(sec)(cm)(min)(cm/sec)
9:05 0.0 24.0 0.0 24.0 0.0
9:06 2.7 21.5 60.0 18.8 1.0 1.03E-04 0.9 13.5 12.5
9:07 5.2 19.0 60.0 13.8 2.0 1.03E-04 1.0 12.5 12.5
9:08 7.5 16.5 60.0 9.0 3.0 1.03E-04 1.1 11.5 12.5
9:09 9.8 14.2 60.0 4.4 4.0 1.03E-04 1.0 11.5 11.5
9:10 12.0 12.0 60.0 0.0 5.0 1.02E-04 1.0 11 11
9:11 14.0 10.0 60.0 -4.0 6.0 9.63E-05 1.0 10 10
9:12 15.8 8.0 60.0 -7.8 7.0 9.48E-05 1.1 9 10
9:13 17.8 6.0 60.0 -11.8 8.0 1.04E-04 1.0 10 10
9:14 19.5 4.2 60.0 -15.3 9.0 9.41E-05 1.1 8.5 9
9:15 21.0 2.5 60.0 -18.5 10.0 8.90E-05 1.1 7.5 8.5
9:16 22.8 1.0 60.0 -21.8 11.0 9.50E-05 0.8 9 7.5
9:18 0.0 24.5 120.0 24.5 13.0
9:19 2.8 21.5 60.0 18.7 14.0 1.15E-04 1.1 14 15
9:20 5.6 19.0 60.0 13.4 15.0 1.10E-04 0.9 14 12.5
9:21 7.6 16.4 60.0 8.8 16.0 9.90E-05 1.3 10 13
9:22 10.0 14.0 60.0 4.0 17.0 1.07E-04 1.0 12 12
9:23 12.2 11.8 60.0 -0.4 18.0 1.02E-04 1.0 11 11
9:24 14.6 9.5 60.0 -5.1 19.0 1.14E-04 1.0 12 11.5
9:25 16.7 7.6 60.0 -9.1 20.0 1.01E-04 0.9 10.5 9.5
9:26 18.0 5.6 60.0 -12.4 21.0 8.62E-05 1.5 6.5 10
9:27 19.9 4.1 60.0 -15.8 22.0 9.19E-05 0.8 9.5 7.5
9:28 21.6 2.0 60.0 -19.6 23.0 1.07E-04 1.2 8.5 10.5
9:29 23.3 0.4 60.0 -22.9 24.0 9.62E-05 0.9 8.5 8
K (cm/s) =9.5E-05
Wisconsin Geotechnics Laboratory
Hydraulic Conductivity Test
ASTM D 5084
Sample I.D. E3_(A1/A2)7/17/12
( )
( )
( )

∆
∆
∆+=
2
1
*
*
H
HLntA
L
aa
aaK
outin
outins
Test Date :
Cell Pressure =35.8 psi Diameter of Sample, D = 15.2 cm
Inflow Pressure = 31.6 psi Length of Sample, L = 11.6 cm
Outflow Pressre =30.0 psi Area of Sample, A = 182.41 cm2
Pressure Difference =1.6 psi Sample Volume, V =2123.9 cm3
Effective Stress = 5.0 psi ain = 5 cm2
Hydraulic Gradient, i =10 aout = 5 cm2
Weight of wet sample =4018.9 (g)Sample Water Content =8.5 (%)
Wet Density =1.9 g/cm3 Dry Density =1.74 g/cm3
Can #WT of Can WT of Can
+ Wet Soil
WT of Can +
Dry Soil
Water
Content
(g)(g)(g)(%)
8.50
Date, Time Inflow OutFlow ∆t H Time K Qout / Qin Qin Qout
(sec)(cm)(min)(cm/sec)
10:00:00 0.0 24.5 0.0 24.5 0.0
10:00:10 6.4 18.0 10.0 11.6 0.2 1.58E-03 1.0 32 32.5
10:00:20 11.6 12.5 10.0 0.9 0.3 1.44E-03 1.1 26 27.5
10:00:30 16.4 7.5 10.0 -8.9 0.5 1.44E-03 1.0 24 25
10:00:40 20.6 3.0 10.0 -17.6 0.7 1.40E-03 1.1 21 22.5
10:03:00 0.0 24.5 140.0 24.5 3.0
10:03:10 6.2 18.0 10.0 11.8 3.2 1.55E-03 1.0 31 32.5
10:03:20 11.4 12.6 10.0 1.2 3.3 1.42E-03 1.0 26 27
10:03:30 16.2 7.6 10.0 -8.6 3.5 1.44E-03 1.0 24 25
10:03:40 20.6 2.9 10.0 -17.7 3.7 1.46E-03 1.1 22 23.5
10:07:00 0.0 24.6 200.0 24.6 7.0 -103
10:07:10 5.9 18.7 10.0 12.8 7.2 1.44E-03 1.0 29.5 29.5
10:07:20 11.2 12.9 10.0 1.7 7.3 1.48E-03 1.1 26.5 29
10:07:30 15.9 7.8 10.0 -8.1 7.5 1.43E-03 1.1 23.5 25.5
10:07:40 20.5 3.2 10.0 -17.3 7.7 1.47E-03 1.0 23 23
10:11:00 0.0 24.6 200.0 24.6 11.0
10:11:10 5.8 18.7 10.0 12.9 11.2 1.42E-03 1.0 29 29.5
10:11:20 11.0 13.0 10.0 2.0 11.3 1.45E-03 1.1 26 28.5
10:11:30 15.9 8.0 10.0 -7.9 11.5 1.44E-03 1.0 24.5 25
10:11:40 20.4 3.3 10.0 -17.1 11.7 1.47E-03 1.0 22.5 23.5
10:15:00 0.0 24.5 200.0 24.5 15.0
10:15:10 5.9 18.5 10.0 12.6 15.2 1.45E-03 1.0 29.5 30
10:15:20 11.0 12.9 10.0 1.9 15.3 1.43E-03 1.1 25.5 28
10:15:30 16.0 7.9 10.0 -8.1 15.5 1.46E-03 1.0 25 25
10:15:40 20.5 3.0 10.0 -17.5 15.7 1.51E-03 1.1 22.5 24.5
10:20:00 0.0 24.7 260.0 24.7 20.0
10:20:10 6.0 18.8 10.0 12.8 20.2 1.45E-03 1.0 30 29.5
10:20:20 11.5 13.2 10.0 1.7 20.3 1.48E-03 1.0 27.5 28
10:20:30 16.3 8.0 10.0 -8.3 20.5 1.46E-03 1.1 24 26
10:20:40 20.8 3.3 10.0 -17.5 20.7 1.47E-03 1.0 22.5 23.5
K (cm/s) =1.5E-03
Wisconsin Geotechnics Laboratory
Hydraulic Conductivity Test
ASTM D 5084
Sample I.D. W2_(B1/B2)7/17/12
( )
( )
( )

∆
∆
∆+=
2
1
*
*
H
HLntA
L
aa
aaK
outin
outins
Test Date :
Cell Pressure =35.8 psi Diameter of Sample, D = 15.2 cm
Inflow Pressure = 31.6 psi Length of Sample, L = 11.6 cm
Outflow Pressre =30.0 psi Area of Sample, A = 182.41 cm2
Pressure Difference =1.6 psi Sample Volume, V =2123.9 cm3
Effective Stress = 5.0 psi ain = 5 cm2
Hydraulic Gradient, i =10 aout = 5 cm2
Weight of wet sample =3878.3 (g)Sample Water Content =10.0 (%)
Wet Density =1.8 g/cm3 Dry Density =1.66 g/cm3
Can #WT of Can WT of Can
+ Wet Soil
WT of Can +
Dry Soil
Water
Content
(g)(g)(g)(%)
10.00
Date, Time Inflow OutFlow ∆t H Time K Qout / Qin Qin Qout
(sec)(cm)(min)(cm/sec)
10:56:00 0.0 24.2 0.0 24.2 0.0
10:56:10 5.4 18.8 10.0 13.4 0.2 1.31E-03 1.0 27 27
10:56:20 9.4 14.8 10.0 5.4 0.3 1.05E-03 1.0 20 20
10:56:30 12.9 11.2 10.0 -1.7 0.5 9.91E-04 1.0 17.5 18
10:56:40 16.4 7.8 10.0 -8.6 0.7 1.03E-03 1.0 17.5 17
10:56:50 19.6 4.6 10.0 -15.0 0.8 1.01E-03 1.0 16 16
10:57:00 22.3 1.8 10.0 -20.5 1.0 9.26E-04 1.0 13.5 14
11:00:00 0.0 24.2 180.0 24.2 4.0
11:00:10 5.0 19.2 10.0 14.2 4.2 1.21E-03 1.0 25 25
11:00:20 9.0 15.0 10.0 6.0 4.3 1.07E-03 1.1 20 21
11:00:30 13.0 11.2 10.0 -1.8 4.5 1.09E-03 1.0 20 19
11:00:40 16.5 7.7 10.0 -8.8 4.7 1.04E-03 1.0 17.5 17.5
11:00:50 19.7 4.4 10.0 -15.3 4.8 1.03E-03 1.0 16 16.5
11:01:00 22.8 1.4 10.0 -21.4 5.0 1.03E-03 1.0 15.5 15
11:05:00 0.0 24.5 240.0 24.5 9.0
11:05:10 4.7 19.8 10.0 15.1 9.2 1.13E-03 1.0 23.5 23.5
11:05:20 8.9 15.6 10.0 6.7 9.3 1.09E-03 1.0 21 21
11:05:30 12.8 11.6 10.0 -1.2 9.5 1.09E-03 1.0 19.5 20
11:05:40 16.6 8.0 10.0 -8.6 9.7 1.10E-03 0.9 19 18
11:05:50 19.7 4.8 10.0 -14.9 9.8 9.98E-04 1.0 15.5 16
11:06:00 22.7 1.8 10.0 -20.9 10.0 1.01E-03 1.0 15 15
11:12:00 0.0 24.5 360.0 24.5 16.0
11:12:10 4.8 19.8 10.0 15.0 16.2 1.15E-03 1.0 24 23.5
11:12:20 8.9 15.5 10.0 6.6 16.3 1.09E-03 1.0 20.5 21.5
11:12:30 12.8 11.6 10.0 -1.2 16.5 1.08E-03 1.0 19.5 19.5
11:12:40 16.3 8.1 10.0 -8.2 16.7 1.04E-03 1.0 17.5 17.5
11:12:50 19.6 4.8 10.0 -14.8 16.8 1.04E-03 1.0 16.5 16.5
11:13:00 22.6 1.8 10.0 -20.8 17.0 1.01E-03 1.0 15 15
11:17:00 0.0 24.5 240.0 24.5 21.0
11:17:10 4.7 19.7 10.0 15.0 21.2 1.15E-03 1.0 23.5 24
11:17:20 8.9 16.5 10.0 7.6 21.3 9.54E-04 0.8 21 16
11:17:30 12.9 11.6 10.0 -1.3 21.5 1.23E-03 1.2 20 24.5
11:17:40 16.5 8.0 10.0 -8.5 21.7 1.07E-03 1.0 18 18
11:17:50 19.8 4.7 10.0 -15.1 21.8 1.05E-03 1.0 16.5 16.5
11:18:00 22.7 1.7 10.0 -21.0 22.0 9.97E-04 1.0 14.5 15
K (cm/s) =1.1E-03
Wisconsin Geotechnics Laboratory
Hydraulic Conductivity Test
ASTM D 5084
Sample I.D. W5_(B1/B2)7/17/12
( )
( )
( )

∆
∆
∆+=
2
1
*
*
H
HLntA
L
aa
aaK
outin
outins
Test Date :
Cell Pressure =35.8 psi Diameter of Sample, D = 15.2 cm
Inflow Pressure = 31.6 psi Length of Sample, L = 11.6 cm
Outflow Pressre =30.0 psi Area of Sample, A = 182.41 cm2
Pressure Difference =1.6 psi Sample Volume, V =2123.9 cm3
Effective Stress = 5.0 psi ain = 5 cm2
Hydraulic Gradient, i =10 aout = 5 cm2
Weight of wet sample =3823.8 (g)Sample Water Content =13.0 (%)
Wet Density =1.8 g/cm3 Dry Density =1.59 g/cm3
Can #WT of Can WT of Can
+ Wet Soil
WT of Can +
Dry Soil
Water
Content
(g)(g)(g)(%)
13.00
Date, Time Inflow OutFlow ∆t H Time K Qout / Qin Qin Qout
(sec)(cm)(min)(cm/sec)
11:41:00 0.0 24.5 0.0 24.5 0.0
11:41:10 5.3 19.6 10.0 14.3 0.2 1.23E-03 0.9 26.5 24.5
11:41:20 10.0 14.8 10.0 4.8 0.3 1.24E-03 1.0 23.5 24
11:41:30 14.4 10.5 10.0 -3.9 0.5 1.23E-03 1.0 22 21.5
11:41:40 18.3 6.4 10.0 -11.9 0.7 1.22E-03 1.1 19.5 20.5
11:41:50 21.8 3.0 10.0 -18.8 0.8 1.13E-03 1.0 17.5 17
11:45:00 0.0 24.0 190.0 24.0 4.0
11:45:10 4.9 19.0 10.0 14.1 4.2 1.20E-03 1.0 24.5 25
11:45:20 9.5 14.3 10.0 4.8 4.3 1.22E-03 1.0 23 23.5
11:45:30 13.8 10.0 10.0 -3.8 4.5 1.21E-03 1.0 21.5 21.5
11:45:40 17.6 6.1 10.0 -11.5 4.7 1.17E-03 1.0 19 19.5
11:45:50 21.0 2.7 10.0 -18.3 4.8 1.11E-03 1.0 17 17
11:48:00 0.0 24.0 130.0 24.0 7.0
11:48:10 4.9 19.0 10.0 14.1 7.2 1.20E-03 1.0 24.5 25
11:48:20 9.4 15.5 10.0 6.1 7.3 1.04E-03 0.8 22.5 17.5
11:48:30 13.5 10.3 10.0 -3.2 7.5 1.30E-03 1.3 20.5 26
11:48:40 17.4 6.4 10.0 -11.0 7.7 1.18E-03 1.0 19.5 19.5
11:48:50 20.9 2.9 10.0 -18.0 7.8 1.14E-03 1.0 17.5 17.5
11:55:00 0.0 24.5 370.0 24.5 14.0
11:55:10 4.9 19.5 10.0 14.6 14.2 1.20E-03 1.0 24.5 25
11:55:20 9.5 14.9 10.0 5.4 14.3 1.20E-03 1.0 23 23
11:55:30 13.6 10.8 10.0 -2.8 14.5 1.15E-03 1.0 20.5 20.5
11:55:40 17.4 7.0 10.0 -10.4 14.7 1.15E-03 1.0 19 19
11:55:50 20.9 3.4 10.0 -17.5 14.8 1.15E-03 1.0 17.5 18
12:00:00 0.0 24.5 250.0 24.5 19.0
12:00:10 4.9 19.5 10.0 14.6 19.2 1.20E-03 1.0 24.5 25
12:00:20 9.2 14.9 10.0 5.7 19.3 1.16E-03 1.1 21.5 23
12:00:30 13.3 11.0 10.0 -2.3 19.5 1.12E-03 1.0 20.5 19.5
12:00:40 17.2 6.9 10.0 -10.3 19.7 1.20E-03 1.1 19.5 20.5
12:00:50 20.9 3.3 10.0 -17.6 19.8 1.18E-03 1.0 18.5 18
K (cm/s) =1.2E-03
Wisconsin Geotechnics Laboratory
Hydraulic Conductivity Test
ASTM D 5084
Sample I.D. W8_(A1/A2)7/17/12
( )
( )
( )

∆
∆
∆+=
2
1
*
*
H
HLntA
L
aa
aaK
outin
outins
Test Date :
Cell Pressure =35.8 psi Diameter of Sample, D = 15.2 cm
Inflow Pressure = 31.6 psi Length of Sample, L = 11.6 cm
Outflow Pressre =30.0 psi Area of Sample, A = 182.41 cm2
Pressure Difference =1.6 psi Sample Volume, V =2123.9 cm3
Effective Stress = 5.0 psi ain = 5 cm2
Hydraulic Gradient, i =10 aout = 5 cm2
Weight of wet sample =3792.1 (g)Sample Water Content =14.0 (%)
Wet Density =1.8 g/cm3 Dry Density =1.57 g/cm3
Can #WT of Can WT of Can
+ Wet Soil
WT of Can +
Dry Soil
Water
Content
(g)(g)(g)(%)
14.00
Date, Time Inflow OutFlow ∆t H Time K Qout / Qin Qin Qout
(sec)(cm)(min)(cm/sec)
13:01:00 0.0 24.0 0.0 24.0 0.0
13:01:10 1.8 22.6 10.0 20.8 0.2 3.78E-04 0.8 9 7
13:01:20 3.4 21.0 10.0 17.6 0.3 3.88E-04 1.0 8 8
13:01:30 5.0 19.6 10.0 14.6 0.5 3.72E-04 0.9 8 7
13:01:40 6.5 18.0 10.0 11.5 0.7 3.94E-04 1.1 7.5 8
13:01:50 8.0 16.6 10.0 8.6 0.8 3.78E-04 0.9 7.5 7
13:02:00 9.4 15.1 10.0 5.7 1.0 3.87E-04 1.1 7 7.5
13:02:10 10.9 13.8 10.0 2.9 1.2 3.82E-04 0.9 7.5 6.5
13:02:20 12.2 12.4 10.0 0.2 1.3 3.78E-04 1.1 6.5 7
13:02:30 13.6 11.0 10.0 -2.6 1.5 4.01E-04 1.0 7 7
13:02:40 14.9 9.8 10.0 -5.1 1.7 3.67E-04 0.9 6.5 6
13:02:50 16.2 8.5 10.0 -7.7 1.8 3.91E-04 1.0 6.5 6.5
13:03:00 17.5 7.2 10.0 -10.3 2.0 4.01E-04 1.0 6.5 6.5
13:03:10 18.8 6.0 10.0 -12.8 2.2 3.95E-04 0.9 6.5 6
13:03:20 20.0 4.9 10.0 -15.1 2.3 3.72E-04 0.9 6 5.5
13:03:30 21.0 3.8 10.0 -17.2 2.5 3.48E-04 1.1 5 5.5
13:03:40 22.3 2.6 10.0 -19.7 2.7 4.24E-04 0.9 6.5 6
13:03:50 23.6 1.5 10.0 -22.1 2.8 4.18E-04 0.8 6.5 5.5
13:07:00 0.0 24.0 190.0 24.0 6.0
13:07:20 3.6 20.5 20.0 16.9 6.3 4.26E-04 1.0 18 17.5
13:07:40 6.9 17.1 20.0 10.2 6.7 4.24E-04 1.0 16.5 17
13:08:00 9.9 14.3 20.0 4.4 7.0 3.86E-04 0.9 15 14
13:08:20 12.8 11.6 20.0 -1.2 7.3 3.92E-04 0.9 14.5 13.5
13:08:40 15.4 8.8 20.0 -6.6 7.7 3.97E-04 1.1 13 14
13:09:00 18.0 6.3 20.0 -11.7 8.0 3.94E-04 1.0 13 12.5
13:09:20 20.5 3.8 20.0 -16.7 8.3 4.06E-04 1.0 12.5 12.5
13:09:40 23.0 1.6 20.0 -21.4 8.7 4.01E-04 0.9 12.5 11
13:13:00 0.0 24.0 200.0 24.0 12.0
13:13:30 5.0 19.0 30.0 14.0 12.5 4.05E-04 1.0 25 25
13:14:00 9.7 14.3 30.0 4.6 13.0 4.11E-04 1.0 23.5 23.5
13:14:30 14.0 10.0 30.0 -4.0 13.5 4.06E-04 1.0 21.5 21.5
13:15:00 18.0 6.2 30.0 -11.8 14.0 3.97E-04 1.0 20 19
13:15:30 21.8 2.6 30.0 -19.2 14.5 4.06E-04 0.9 19 18
13:20:00 0.0 24.5 270.0 24.5 19.0
Wisconsin Geotechnics Laboratory
Hydraulic Conductivity Test
ASTM D 5084 - 00
Sample I.D. W9_(B1/B2)7/17/12
( )
( )
( )

∆
∆
∆+=
2
1
*
*
H
HLntA
L
aa
aaK
outin
outins
13:20:20 3.5 21.0 20.0 17.5 19.3 4.18E-04 1.0 17.5 17.5
13:20:40 6.7 17.8 20.0 11.1 19.7 4.03E-04 1.0 16 16
13:21:00 9.9 14.7 20.0 4.8 20.0 4.17E-04 1.0 16 15.5
13:21:20 12.9 11.8 20.0 -1.1 20.3 4.12E-04 1.0 15 14.5
13:21:40 15.7 9.2 20.0 -6.5 20.7 3.96E-04 0.9 14 13
13:22:00 18.3 6.6 20.0 -11.7 21.0 4.01E-04 1.0 13 13
13:22:20 20.9 4.0 20.0 -16.9 21.3 4.22E-04 1.0 13 13
K (cm/s) =4.1E-04
Sample I.D.Test Date
70.9 g Gs =2.61 6/16/2012
100.3 pcf
11.0 %
7.26 cm
2.54 cm
105.27 cm3
After Saturation, Sample Height Swell -0.02 cm
After Saturation, Sample Dry Density 1.62 (g/cm3)
23.4 %
37.92 %
Gravimetric Volumetric
Water Water
Content Content
(psi)(kPa)
0 0.001 0.234 0.379
0.25 1.724 0.235 0.381
0.5 3.449 0.234 0.379
1 6.897 0.230 0.372
2 13.794 0.207 0.335
4 27.588 0.148 0.240
8 55.176 0.130 0.211
15 103.455 0.117 0.189
30 206.910 0.108 0.175
61 420.717 0.104 0.168
0.000 0.239 0.386
0.000 0.239 0.386
Activity 360.00 0.066 0.106
Meter 4090.00 0.042 0.068
Test 49640.00 0.022 0.035
Activity Meter Test
Wt of Can Wt of Can Gravimetric Volumetric
++ Water Water
Wet Soil Dry Soil Content Content
(Mpa)(g)(g)(g)
49.64 7.6704 15.1835 15.0238 0.022 0.035
4.09 7.7126 15.3462 15.037 0.042 0.068
0.36 8.0127 15.8145 15.3346 0.066 0.106
Sample Volume, V =
Applied Pressure Reading
4.1
8
116
96.5
108.5
28.4
80.5
Suction Wt of Can
120
Geotechnics Laboratory
University of Wisconsin-Madison
(cm)
4
3.2
Pressure Plate Extractor Test
ASTM D 6836 - 02 (Method B)
E1_(A1/A2)
WT of Sample Ring =
Provided Water Content, w =
Diameter of Sample Ring, D =
Suction
Provided Dry Density, γd =
Height of Sample Ring, L =
Saturaded Water Content, w =
Saturaded Water Content, θ =
0.001 0.379 0.3792 0.000 0.000
1.72 0.381 0.3731 0.008 0.000
3.45 0.379 0.3646 0.014 0.000
θr =0.0236 6.90 0.372 0.3468 0.025 0.001
θs =0.3792 13.79 0.335 0.3157 0.019 0.000
α =0.0797 27.59 0.240 0.2736 -0.034 0.001
n =1.3495 55.18 0.211 0.2287 -0.018 0.000
m =0.2590 103.46 0.189 0.1913 -0.002 0.000
206.91 0.175 0.1563 0.019 0.000
420.72 0.168 0.1276 0.041 0.002
360.00 0.106 0.1333 -0.027 0.001
4090.00 0.068 0.0707 -0.002 0.000
0.001 0.3792 49640.00 0.035 0.0433 -0.008 0.000
0.025 0.3791
0.05 0.3791 Residual =0.000425339
0.075 0.3791
0.1 0.3790 press plate data (FROM PAGE 2)
0.15 0.3789 water activity meter data (FROM PAGE 2)
0.25 0.3787
0.5 0.3780
0.75 0.3771
1 0.3762
1.25 0.3752
1.5 0.3741
2 0.3718
3 0.3669
4 0.3618
5 0.3566
6 0.3514
7 0.3463
8 0.3413
9 0.3365
10 0.3318
15 0.3111
20 0.2941
30 0.2682
40 0.2494
50 0.2349
60 0.2234
70 0.2139
80 0.2060
90 0.1991
100 0.1931
500 0.1215
1000 0.1005
5000 0.0675
10000 0.0580
25000 0.0486
5.00E+04 0.0432
1.00E+05 0.0390
van Genuchten Eqn
Fit van Genuchten Eqn to SWCC Data
FOR GRAPHING
Suction (kPa)VWC
FOR FITTING
(∆WC)2∆WC (%)Predicted
VWC
Applied Suction
(kPa)
Measured
VWC
( )
m
nrs
r
1
1 


αψ+=θ−θ
θ−θ=Θ
0.001
0.01
0.1
1
10
100
1000
10000
100000
1000000
0.0 0.1 0.2 0.3 0.4
Su
c
t
i
o
n

(
k
P
a
)

Fitted Data
Pressure Plate Test
Activity Meter
Sample I.D.Test Date 6/16/2012
69.2 g Gs =2.53
89.25 pcf
19.0 %
7.26 cm
2.54 cm
105.27 cm3
After Saturation, Sample Height Swell 0.02 cm
After Saturation, Sample Dry Density 1.42 (g/cm3)
31.0 %
43.90 %
Gravimetric Volumetric
Water Water
Content Content
(psi)(kPa)
0 0.001 0.310 0.439
0.25 1.724 0.308 0.436
0.5 3.449 0.306 0.434
1 6.897 0.304 0.431
2 13.794 0.273 0.387
4 27.588 0.248 0.352
10 68.970 0.219 0.310
20 137.940 0.190 0.269
40 275.880 0.174 0.247
82 565.554 0.163 0.231
0.000 0.324 0.459
0.000 0.324 0.459
Activity 4130.00 0.107 0.152
Meter 9560.00 0.087 0.123
Test 36450.00 0.067 0.096
Activity Meter Test
Wt of Can Wt of Can Gravimetric Volumetric
++ Water Water
Wet Soil Dry Soil Content Content
(Mpa)(g)(g)(g)
36.45 7.7599 14.4494 14.0272 0.067 0.096
9.56 7.7453 14.5806 14.0358 0.087 0.123
4.13 7.5893 14.5888 13.9098 0.107 0.152
Geotechnics Laboratory
University of Wisconsin-Madison
(cm)
11.1
12.7
Pressure Plate Extractor Test
ASTM D 6836 - 02 (Method B)
E3_(A1/A2)
WT of Sample Ring =
Provided Water Content, w =
Diameter of Sample Ring, D =
Suction
Provided Dry Density, γd =
Height of Sample Ring, L =
Saturaded Water Content, w =
Saturaded Water Content, θ =
Suction Wt of Can
127.5
118.5
83
106
40.4
59.5
Sample Volume, V =
Applied Pressure Reading
14
15.5
0.001 0.439 0.4390 0.000 0.000
1.72 0.436 0.4329 0.003 0.000
3.45 0.434 0.4259 0.008 0.000
θr =0.0000 6.90 0.431 0.4126 0.019 0.000
θs =0.4390 13.79 0.387 0.3905 -0.004 0.000
α =0.0787 27.59 0.352 0.3602 -0.008 0.000
n =1.1870 68.97 0.310 0.3137 -0.003 0.000
m =0.1575 137.94 0.269 0.2786 -0.009 0.000
275.88 0.247 0.2459 0.001 0.000
565.55 0.231 0.2155 0.015 0.000
4130.00 0.152 0.1489 0.003 0.000
9560.00 0.123 0.1273 -0.004 0.000
0.001 0.4390 36450.00 0.096 0.0991 -0.004 0.000
0.025 0.4390
0.05 0.4389 Residual =6.70081E-05
0.075 0.4389
0.1 0.4388 press plate data (FROM PAGE 2)
0.15 0.4387 water activity meter data (FROM PAGE 2)
0.25 0.4384
0.5 0.4376
0.75 0.4367
1 0.4358
1.25 0.4348
1.5 0.4338
2 0.4318
3 0.4277
4 0.4237
5 0.4197
6 0.4159
7 0.4122
8 0.4086
9 0.4052
10 0.4019
15 0.3873
20 0.3752
30 0.3562
40 0.3418
50 0.3303
60 0.3209
70 0.3129
80 0.3061
90 0.3000
100 0.2946
500 0.2205
1000 0.1939
5000 0.1436
10000 0.1262
25000 0.1063
5.00E+04 0.0934
1.00E+05 0.0821
van Genuchten Eqn
Fit van Genuchten Eqn to SWCC Data
FOR GRAPHING
Suction (kPa)VWC
FOR FITTING
(∆WC)2∆WC (%)Predicted
VWC
Applied Suction
(kPa)
Measured
VWC
( )
m
nrs
r
1
1 


αψ+=θ−θ
θ−θ=Θ
0.001
0.01
0.1
1
10
100
1000
10000
100000
1000000
0.0 0.1 0.2 0.3 0.4 0.5
Su
c
t
i
o
n

(
k
P
a
)

Fitted Data
Pressure Plate Test
Activity Meter
Sample I.D.Test Date
200 cm3 Gs =2.63
Solid WT =348.5 g
Water WT = 67 g
1.74 g/cm3 108.78 pcf
19.3 %
0.19 cm2
Left Manometer
Reading
Right Manometer
Reading
Horizontal
Outflow
Reading
Water
Expelled
from Soil
Sample
Suction Grav. Water
Content
Volumetric
Water
Content
(cm)(cm)(cm)(mL)(cm)
199 199 2.5 0.000 0.19 0.34
201 197.7 24 4.085 3.300 0.18 0.32
202.8 195.7 31 5.415 7.100 0.18 0.31
206.1 192.4 38 6.745 13.700 0.17 0.30
209.4 189.1 42 7.505 20.300 0.17 0.30
213.5 185 46.6 8.379 28.500 0.17 0.30
216.5 182 52.4 9.481 34.500 0.17 0.29
221 177.5 59 10.735 43.500 0.16 0.28
225 173.1 72 13.205 51.900 0.16 0.27
229 168.5 79.3 14.592 60.500 0.15 0.26
235.2 163.1 96 17.765 72.100 0.14 0.25
248 150 119.4 22.211 98.000 0.13 0.23
257.5 140.8 131 24.415 116.700 0.12 0.21
266.5 131.5 144.5 26.980 135.000 0.12 0.20
287.5 110.5 163.5 30.590 177.000 0.11 0.18
317.5 81 176 32.965 236.500 0.10 0.17
391.5 6.5 200 37.525 385.000 0.09 0.15
-0.475 0.000 0.19 0.34
-0.475 0.000 0.19 0.34
2448.00 0.059 0.104
1.0 MPa = 1000.0 kPa Activity 11424.00 0.037 0.065
1.0 kPa = 10.2 cm Meter 264588.00 0.014 0.025
Test
Activity Meter Test
Suction Wt of Can Wt of Can
+ Wet Soil
Wt of Can
+ Dry Soil
Gravimetric
Water
Content
Volumetric
Water
Content
(Mpa)(g)(g)(g)
25.94 7.6398 15.8339 15.719 0.014 0.025
1.12 7.8975 16.1932 15.8943 0.037 0.065
0.24 8.0743 16.5516 16.0763 0.059 0.104
Geotechnics Laboratory
University of Wisconsin-Madison
Tube Area, A =
Volume, V =
Dry Unit Weight =
Hanging Column and Activity Meter Test
ASTM D 6836 - 02 (Method A and D)
W2_(B1/B2)
Saturated Water Content =
0.001 0.337 0.3166 0.020 0.000
3.30 0.317 0.3143 0.002 0.000
7.10 0.310 0.3104 -0.001 0.000
θr =0.0000 13.70 0.303 0.3029 0.000 0.000
θs =0.3166 20.30 0.299 0.2950 0.004 0.000
α =0.0216 28.50 0.295 0.2856 0.009 0.000
n =1.3212 34.50 0.290 0.2792 0.010 0.000
m =0.2431 43.50 0.283 0.2701 0.013 0.000
51.90 0.271 0.2625 0.009 0.000
60.50 0.264 0.2553 0.009 0.000
72.10 0.248 0.2466 0.002 0.000
98.00 0.226 0.2304 -0.004 0.000
0.001 0.3166 116.70 0.215 0.2209 -0.006 0.000
0.025 0.3166 135.00 0.202 0.2129 -0.011 0.000
0.05 0.3166 177.00 0.184 0.1981 -0.014 0.000
0.075 0.3166 236.50 0.172 0.1826 -0.010 0.000
0.1 0.3166 385.00 0.149 0.1581 -0.009 0.000
0.15 0.3166 2448.00 0.104 0.0884 0.015 0.000
0.25 0.3165 11424.00 0.065 0.0540 0.011 0.000
0.5 0.3164 264588.00 0.025 0.0197 0.005 0.000
0.75 0.3163 Residual =9.49943E-05
1 0.3161
1.25 0.3159 press plate data (FROM PAGE 2)
1.5 0.3158 water activity meter data (FROM PAGE 2)
2 0.3154
3 0.3146
4 0.3136
5 0.3127
6 0.3116
7 0.3106
8 0.3095
9 0.3083
10 0.3072
15 0.3013
20 0.2954
25 0.2896
30 0.2840
35 0.2786
40 0.2735
45 0.2687
50 0.2641
55 0.2598
60 0.2557
62 0.2541
65 0.2518
67 0.2503
70 0.2481
75 0.2446
80 0.2412
Measured
VWC
van Genuchten Eqn
Fit van Genuchten Eqn to SWCC Data
FOR GRAPHING
Suction (cm)VWC
FOR FITTING
(∆WC)2∆WC (%)Predicted
VWC
Applied Suction
(cm)
( )
m
nrs
r
1
1 


αψ+=θ−θ
θ−θ=Θ
0.001
0.01
0.1
1
10
100
1000
10000
100000
1000000
0.0 0.1 0.2 0.3 0.4
Su
c
t
i
o
n

(
c
m
)
Volumetric Water Content
Fitted and Lab Data
Fitted Data
Hanging Column
Activity Meter
Sample I.D.Test Date
200 cm3 Gs =2.63
Solid WT =332.2 g
Water WT = 74 g
1.661 g/cm3 103.7 pcf
22 %
0.19 cm2
Left Manometer
Reading
Right Manometer
Reading
Horizontal
Outflow
Reading
Water
Expelled
from Soil
Sample
Suction Grav. Water
Content
Volumetric
Water
Content
(cm)(cm)(cm)(mL)(cm)
198.5 198.5 2.8 0.000 0.22 0.37
201 197.2 13 1.938 3.800 0.22 0.36
202.6 195.4 20.8 3.420 7.200 0.21 0.35
205.7 192.1 28.7 4.921 13.600 0.21 0.34
209 189 34.2 5.966 20.000 0.20 0.34
213.2 184.6 39.3 6.935 28.600 0.20 0.33
216.3 181.4 41.5 7.353 34.900 0.20 0.33
221.8 175.8 42.5 7.543 46.000 0.20 0.33
227.5 170 47.5 8.493 57.500 0.20 0.33
232.3 165.2 52.6 9.462 67.100 0.19 0.32
237.6 159.7 67 12.198 77.900 0.18 0.31
249.5 148 80.5 14.763 101.500 0.18 0.29
256 141 86 15.808 115.000 0.17 0.29
265 132 99 18.278 133.000 0.17 0.28
281.8 115 124 23.028 166.800 0.15 0.25
314.5 81.5 150 27.968 233.000 0.14 0.23
388 8 188 35.188 380.000 0.12 0.19
-0.532 0.000 0.22 0.37
-0.532 0.000 0.22 0.37
4794.00 0.057 0.095
1.0 MPa = 1000.0 kPa Activity 17544.00 0.035 0.058
1.0 kPa = 10.2 cm Meter 320280.00 0.013 0.022
Test
Activity Meter Test
Suction Wt of Can Wt of Can
+ Wet Soil
Wt of Can
+ Dry Soil
Gravimetric
Water
Content
Volumetric
Water
Content
(Mpa)(g)(g)(g)
31.4 7.7689 15.4851 15.3826 0.013 0.022
1.72 7.6668 15.5828 15.3142 0.035 0.058
0.47 7.6092 15.7261 15.2859 0.057 0.095
Geotechnics Laboratory
University of Wisconsin-Madison
Tube Area, A =
Volume, V =
Dry Unit Weight =
Hanging Column and Activity Meter Test
ASTM D 6836 - 02 (Method A and D)
W5_(B1/B2)
Saturated Water Content =
0.001 0.368 0.3583 0.010 0.000
3.80 0.358 0.3569 0.001 0.000
7.20 0.351 0.3550 -0.004 0.000
θr =0.0000 13.60 0.343 0.3508 -0.007 0.000
θs =0.3583 20.00 0.338 0.3461 -0.008 0.000
α =0.0118 28.60 0.333 0.3395 -0.006 0.000
n =1.3487 34.90 0.331 0.3346 -0.003 0.000
m =0.2586 46.00 0.330 0.3260 0.004 0.000
57.50 0.326 0.3175 0.008 0.000
67.10 0.321 0.3108 0.010 0.000
77.90 0.307 0.3036 0.003 0.000
101.50 0.294 0.2895 0.005 0.000
0.001 0.3583 115.00 0.289 0.2822 0.007 0.000
0.025 0.3583 133.00 0.277 0.2734 0.003 0.000
0.05 0.3583 166.80 0.253 0.2591 -0.006 0.000
0.075 0.3583 233.00 0.228 0.2372 -0.009 0.000
0.1 0.3583 380.00 0.192 0.2054 -0.013 0.000
0.15 0.3583 4794.00 0.095 0.0875 0.008 0.000
0.25 0.3583 17544.00 0.058 0.0557 0.003 0.000
0.5 0.3582 320280.00 0.022 0.0202 0.002 0.000
0.75 0.3582 Residual =4.58839E-05
1 0.3581
1.25 0.3580 press plate data (FROM PAGE 2)
1.5 0.3579 water activity meter data (FROM PAGE 2)
2 0.3577
3 0.3573
4 0.3568
5 0.3563
6 0.3557
7 0.3552
8 0.3546
9 0.3539
10 0.3533
15 0.3498
20 0.3461
25 0.3423
30 0.3384
35 0.3345
40 0.3306
45 0.3268
50 0.3230
55 0.3193
60 0.3157
62 0.3143
65 0.3122
67 0.3109
70 0.3088
75 0.3055
80 0.3023
Measured
VWC
van Genuchten Eqn
Fit van Genuchten Eqn to SWCC Data
FOR GRAPHING
Suction (cm)VWC
FOR FITTING
(∆WC)2∆WC (%)Predicted
VWC
Applied Suction
(cm)
( )
m
nrs
r
1
1 


αψ+=θ−θ
θ−θ=Θ
0.001
0.01
0.1
1
10
100
1000
10000
100000
1000000
0.0 0.1 0.2 0.3 0.4
Su
c
t
i
o
n

(
c
m
)

Volumetric Water Content
Fitted and Lab Data
Fitted Data
Hanging Column
Activity Meter
Sample I.D.Test Date
200 cm3 Gs =2.64
Solid WT =318.5 g
Water WT = 79 g
1.59 g/cm3 99.41 pcf
25 %
0.19 cm2
Left Manometer
Reading
Right Manometer
Reading
Horizontal
Outflow
Reading
Water
Expelled
from Soil
Sample
Suction Grav. Water
Content
Volumetric
Water
Content
(cm)(cm)(cm)(mL)(cm)
198.3 198.3 0.8 0.000 0.25 0.40
200 197 24.5 4.503 3.000 0.23 0.37
202 195 30.4 5.624 7.000 0.23 0.37
205 191.8 35.6 6.612 13.200 0.23 0.36
208.3 188.5 38.9 7.239 19.800 0.23 0.36
212 184.8 41.9 7.809 27.200 0.22 0.36
215.4 181.1 43.5 8.113 34.300 0.22 0.36
220.4 176.3 50 9.348 44.100 0.22 0.35
223.7 173 66.1 12.407 50.700 0.21 0.33
228.6 168 79 14.858 60.600 0.20 0.32
233.3 163.4 102.3 19.285 69.900 0.19 0.30
240.5 156 124 23.408 84.500 0.18 0.28
247.3 149.5 139 26.258 97.800 0.17 0.27
257 139.5 160 30.248 117.500 0.15 0.25
276.5 120.5 185 34.998 156.000 0.14 0.22
309.2 88 206 38.988 221.200 0.13 0.20
381 17 233 44.118 364.000 0.11 0.18
-0.152 0.000 0.25 0.40
-0.152 0.000 0.25 0.40
11424.00 0.054 0.087
1.0 MPa = 1000.0 kPa Activity 45798.00 0.034 0.054
1.0 kPa = 10.2 cm Meter 500616.00 0.012 0.020
Test
Activity Meter Test
Suction Wt of Can Wt of Can
+ Wet Soil
Wt of Can
+ Dry Soil
Gravimetric
Water
Content
Volumetric
Water
Content
(Mpa)(g)(g)(g)
49.08 7.9693 15.3475 15.257 0.012 0.020
4.49 10.3871 17.9633 17.7137 0.034 0.054
1.12 8.2429 16.041 15.6388 0.054 0.087
Geotechnics Laboratory
University of Wisconsin-Madison
Tube Area, A =
Volume, V =
Dry Unit Weight =
Hanging Column and Activity Meter Test
ASTM D 6836 - 02 (Method A and D)
W8_(A1/A2)
Saturated Water Content =
0.001 0.396 0.3738 0.023 0.001
3.00 0.374 0.3719 0.002 0.000
7.00 0.368 0.3680 0.000 0.000
θr =0.0000 13.20 0.363 0.3607 0.003 0.000
θs =0.3738 19.80 0.360 0.3524 0.008 0.000
α =0.0184 27.20 0.357 0.3430 0.014 0.000
n =1.3531 34.30 0.356 0.3343 0.022 0.000
m =0.2609 44.10 0.350 0.3229 0.027 0.001
50.70 0.334 0.3158 0.018 0.000
60.60 0.322 0.3059 0.016 0.000
69.90 0.300 0.2974 0.003 0.000
84.50 0.279 0.2854 -0.006 0.000
0.001 0.3738 97.80 0.265 0.2757 -0.011 0.000
0.025 0.3738 117.50 0.245 0.2633 -0.018 0.000
0.05 0.3738 156.00 0.221 0.2437 -0.022 0.000
0.075 0.3738 221.20 0.201 0.2197 -0.018 0.000
0.1 0.3738 364.00 0.176 0.1875 -0.012 0.000
0.15 0.3738 11424.00 0.087 0.0566 0.030 0.001
0.25 0.3738 45798.00 0.054 0.0347 0.020 0.000
0.5 0.3737 500616.00 0.020 0.0149 0.005 0.000
0.75 0.3735 Residual =0.000266321
1 0.3734
1.25 0.3732 press plate data (FROM PAGE 2)
1.5 0.3731 water activity meter data (FROM PAGE 2)
2 0.3727
3 0.3719
4 0.3710
5 0.3701
6 0.3690
7 0.3680
8 0.3669
9 0.3657
10 0.3646
15 0.3584
20 0.3521
25 0.3457
30 0.3395
35 0.3334
40 0.3276
45 0.3219
50 0.3166
55 0.3114
60 0.3065
62 0.3046
65 0.3018
67 0.3000
70 0.2973
75 0.2930
80 0.2889
Measured
VWC
van Genuchten Eqn
Fit van Genuchten Eqn to SWCC Data
FOR GRAPHING
Suction (cm)VWC
FOR FITTING
(∆WC)2∆WC (%)Predicted
VWC
Applied Suction
(cm)
( )
m
nrs
r
1
1 


αψ+=θ−θ
θ−θ=Θ
0.001
0.01
0.1
1
10
100
1000
10000
100000
1000000
0.0 0.1 0.2 0.3 0.4
Su
c
t
i
o
n

(
c
m
)
Volumetric Water Content
Fitted and Lab Data
Fitted Data
Hanging Column
Activity Meter
Sample I.D.Test Date 6/16/2012
71.2 g Gs =2.63
97.75 pcf
14.0 %
7.26 cm
2.54 cm
105.27 cm3
After Saturation, Sample Height Swell -0.01 cm
After Saturation, Sample Dry Density 1.57 (g/cm3)
25.5 %
40.15 %
Gravimetric Volumetric
Water Water
Content Content
(psi)(kPa)
0 0.001 0.255 0.402
0.25 1.724 0.253 0.398
0.5 3.449 0.253 0.398
1 6.897 0.249 0.392
2 13.794 0.228 0.358
4 27.588 0.185 0.291
8.8 60.694 0.159 0.250
15 103.455 0.147 0.231
30 206.910 0.133 0.208
61 420.717 0.124 0.196
0.000 0.260 0.409
0.000 0.260 0.409
Activity 1900.00 0.068 0.107
Meter 9980.00 0.044 0.070
Test 49420.00 0.023 0.037
Activity Meter Test
Wt of Can Wt of Can Gravimetric Volumetric
++ Water Water
Wet Soil Dry Soil Content Content
(Mpa)(g)(g)(g)
49.42 7.5967 14.8996 14.7337 0.023 0.037
9.98 8.4947 15.9007 15.5857 0.044 0.070
1.9 7.6924 15.3037 14.8201 0.068 0.107
Geotechnics Laboratory
University of Wisconsin-Madison
(cm)
4
6
Pressure Plate Extractor Test
ASTM D 6836 - 02 (Method B)
W9_(B1/B2)
WT of Sample Ring =
Provided Water Content, w =
Diameter of Sample Ring, D =
Suction
Provided Dry Density, γd =
Height of Sample Ring, L =
Saturaded Water Content, w =
Saturaded Water Content, θ =
Suction Wt of Can
117.5
110.5
87.5
98.2
28
65
Sample Volume, V =
Applied Pressure Reading
6
9.4
0.001 0.402 0.4015 0.000 0.000
1.72 0.398 0.3957 0.002 0.000
3.45 0.398 0.3884 0.009 0.000
θr =0.0000 6.90 0.392 0.3737 0.018 0.000
θs =0.4015 13.79 0.358 0.3482 0.010 0.000
α =0.0729 27.59 0.291 0.3125 -0.022 0.000
n =1.2569 60.69 0.250 0.2661 -0.016 0.000
m =0.2044 103.46 0.231 0.2352 -0.005 0.000
206.91 0.208 0.1986 0.010 0.000
420.72 0.196 0.1662 0.030 0.001
1900.00 0.107 0.1131 -0.006 0.000
9980.00 0.070 0.0739 -0.004 0.000
0.001 0.4015 49420.00 0.037 0.0490 -0.012 0.000
0.025 0.4015
0.05 0.4014 Residual =0.000187613
0.075 0.4014
0.1 0.4013 press plate data (FROM PAGE 2)
0.15 0.4012 water activity meter data (FROM PAGE 2)
0.25 0.4010
0.5 0.4002
0.75 0.3994
1 0.3985
1.25 0.3976
1.5 0.3966
2 0.3946
3 0.3903
4 0.3860
5 0.3817
6 0.3774
7 0.3732
8 0.3692
9 0.3653
10 0.3615
15 0.3444
20 0.3301
30 0.3077
40 0.2909
50 0.2776
60 0.2668
70 0.2577
80 0.2499
90 0.2431
100 0.2371
500 0.1590
1000 0.1333
5000 0.0882
10000 0.0738
25000 0.0583
5.00E+04 0.0488
1.00E+05 0.0409
van Genuchten Eqn
Fit van Genuchten Eqn to SWCC Data
FOR GRAPHING
Suction (kPa)VWC
FOR FITTING
(∆WC)2∆WC (%)Predicted
VWC
Applied Suction
(kPa)
Measured
VWC
( )
m
nrs
r
1
1 


αψ+=θ−θ
θ−θ=Θ
0.001
0.01
0.1
1
10
100
1000
10000
100000
1000000
0.0 0.1 0.2 0.3 0.4 0.5
Su
c
t
i
o
n

(
k
P
a
)

Volumetric Water Content
Fitted Data
Pressure Plate Test
Activity Meter
Sample WT of WT of Wet Soil WT of Dry Soil Water Suction 15 Bar
I.D.Moisture Can + Moisture Can + Moisture Can Content (MPa)Moisture Content
(G)(g)(g)(%)(See Plots)
7.67 15.7008 15.4575 3.1 13.66
7.7131 15.9538 15.5736 4.8 2.73
8.0119 16.3007 15.8023 6.4 1.14
7.6693 15.6094 15.3727 3.1 39.48
7.713 15.758 15.3519 5.3 6.72
8.0122 16.2961 15.6924 7.9 0.71
7.5901 14.9987 14.769 3.2 22.98
7.7454 15.3792 14.9965 5.3 4.73
7.761 15.5428 14.9547 8.2 0.81
7.5969 15.1856 14.9434 3.3 10.45
8.4944 16.1118 15.7007 5.7 1.84
7.6935 15.6657 15.0576 8.3 0.77
15 Bar (1.5 MPa) Moisture Content
6.0
6.9
7.0
6.4
E8_(B1/B2)
W2_(A1/A2)
W5_(A1/A2)
W8_(B1/B2)
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
9.0
0.1 1 10 100
Mo
i
s
t
u
r
e

C
o
n
t
e
n
t

%

Suction (MPa)
W2_(A1/A2)
W2_(A1/A2)
Power (W2_(A1/A2))
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
9.0
0.1 1 10 100
Mo
i
s
t
u
r
e

C
o
n
t
e
n
t
,

%

Suction (MPa)
W5_(A1/A2)
W5_(A1/A2)
Power (W5_(A1/A2))
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
9.0
0.1 1 10 100
Mo
i
s
t
u
r
e

C
o
n
t
e
n
t
,

%

Suction (MPa)
W8_(B1/B2)
W8_(B1/B2)
Power (W8_(B1/B2))
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
1 10 100
Mo
i
s
t
u
r
e

C
o
n
t
e
n
t

%

Suction (Mpa)
E8_(B1/B2)
E8_(B1/B2)
Power (E8_(B1/B2))

ATTACHMENT C

SUPPORTING DOCUMENTATION FOR INTERROGATORY 02/1 and 08/1:

REVISED APPENDIX G, EROSIONAL STABILITY EVALUATION,
TO THE UPDATED TAILINGS COVER DESIGN REPORT
(APPENDIX D OF RECLAMATION PLAN, REVISION 5.0)

Updated Tailings Cover Design Report
APPENDIX G

EROSIONAL STABILITY EVALUATION

Updated Tailings Cover Design Report
Denison Mines (USA) Corporation MWH Americas, Inc.
G-1 August 2012
G.1 INTRODUCTION
This appendix presents the hydrologic analysis and evaluation of erosion protection for the
cover surface of the White Mesa Mill tailings disposal cells and for the discharge channel and
sedimentation basin. These analyses have been conducted in a manner consistent with Nuclear
Regulatory Commission (NRC) guidelines documented in NRC (1990) and Johnson (2002).
The analyses include the tasks listed below.

1. Selection of the Probable Maximum Precipitation (PMP) as the design event for the
site.
2. Calculation of the peak discharge (due to the PMP) from the surfaces of Cells 1, 2, 3,
4A and 4B for the cover surface, and for the drainage basin for the discharge
channel.
3. Evaluation of reclaimed tailings disposal cell surfaces for erosional stability (the top
surfaces and the reclaimed embankment slopes) and evaluation of the discharge
channel and sedimentation basin for erosional stability.
4. Evaluation of the need for filter material between erosional protection riprap and
underlying soil layers on the transition slopes on the top surface, the reclaimed
embankment slopes, and the rock aprons.
5. Evaluation of the need for a rock apron at the toe of the reclaimed embankment
slopes to accommodate flow transitioning from embankment slopes to native ground.
6. Evaluation of surface sheet erosion of top surface of cells due to action of surface
water and wind.

These tasks are presented in the following sections of this appendix.

G.2 CONCEPTUAL EROSIONAL PROTECTION DESIGN
Erosional protection was evaluated for the proposed monolithic ET cover design based on the
following proposed cover surface of the tailings disposal cells, as well as for the sedimentation
basin and diversion channel:

• Cells 2 and 3 top surfaces graded to 0.5% slope: Erosional protection is provided by 6
inches of topsoil vegetated with a grass mixture providing poor or better vegetated
conditions with a minimum of 30 percent plant coverage (representing drought
conditions).
• Portions of Cell 1 and 2 with top surfaces graded at 1% slope and Cells 4A and 4B with
top surfaces at 0.82% slope: Erosional protection is provided by 6 inches of topsoil
mixed with 25% (by weight) of 1-inch minus (D100 = 1 inch) gravel, vegetated with a grass
mixture providing poor or better vegetated conditions with a minimum of 30 percent plant
coverage (representing drought conditions).
• External side slopes graded to 5 horizontal to 1 vertical (5H:1V): Erosional protection is
provided by various sized angular and rounded riprap with thicknesses ranging from 6 to
8 inches and minimum D50’s ranging from 1.5 to 5.3 inches. Filter material will be
placed between the erosional protection and the underlying soil layer.

Updated Tailings Cover Design Report
Denison Mines (USA) Corporation MWH Americas, Inc.
G-2 August 2012
• Cover transition slopes graded to 10H:1V: Erosional protection is provided by 7 inches
of angular riprap with a minimum D50 of 4.5 inches. Filter material will be placed
between the erosional protection and the underlying soil layer.
• A rock apron at the toe of 5H:1V slopes: Erosional protection and scour protection on
the west and east sides of the cells is provided by a rock apron measuring 10.2 inches
deep and 4.25 feet in width, with a D50 of 3.4 inches. On the south side of cells 4A and
4B, and east side of Cell 4A, the rock apron measures 2.7 feet in depth, 13.2 feet in
width, and has a D50 of 10.6 inches. On the north side slope of the Cell 1 disposal area,
the rock apron measures 2.3 feet deep, 11.3 feet wide, and contains a minimum D50 of
9.0 inches.
• Sedimentation Basin area graded to 0.1% slope: Erosional protection is provided by 6
inches of topsoil vegetated with a grass mixture providing poor or better vegetated
conditions with a minimum of 30 percent plant coverage (representing drought
conditions).
• Diversion Channel: The diversion channel will be excavated into bedrock.

G.3 PROBABLE MAXIMUM PRECIPITATION EVENT
As outlined in NRC (1990) and Johnson (2002), the design event for evaluation of long-term
erosional stability of the reclaimed tailings disposal cells is the PMP. The selected PMP events
used to calculate the peak discharges for evaluation of erosional stability were the six-hour
duration PMP (with a precipitation total of 9.6 inches) and the one-hour duration PMP (with a
precipitation total of 8.3 inches). These events were determined for the site area using
“Hydrometeorological Report (HMR) No. 49: Probable Maximum Precipitation Estimates,
Colorado River and Great Basin Drainages (Hansen et al. 1984) , as well as Jensen (1995).
Rainfall depth versus duration for short-term events (less than 1 hour) was developed using
procedures in HMR 49 and NUREG/CR-4620 (Nelson et al., 1986). PMP calculations were
provided in Denison (2009) and updated in Denison (2012). The calculations are provided in
Attachment G.1.

G.4 CALCULATION OF PEAK DISCHARGE
The peak discharge calculations were made using the Rational Method as described in Johnson
(2002) and Nelson et al. (1986). The time of concentration was calculated for the longest flow
path (see Figure G.1) across the tailings disposal cells using procedures by Kirpich, Soil
Conservation Service (SCS) and Brant and Oberman as presented in Nelson et al. (1986) and
DOE (1989). Equal weight was given to each of the three methods. A runoff coefficient of 1.0
was used to represent PMP conditions (DOE, 1989). These characteristics represent high
runoff quantities and peak flow velocities.

The PMP discharge results across the tailings disposal cells are presented in Table G.1. These
discharges represent flow across a unit-width across the slope.

Updated Tailings Cover Design Report
Denison Mines (USA) Corporation MWH Americas, Inc.
G-3 August 2012
Table G.1. Peak Reclaimed Surface Discharges
Location
Slope
Length
(feet)
Time of
Concentration
(min)
Rainfall
Intensity
(in/hr)
Runoff
Coefficient
Peak Unit
Discharge
(cfs/ft)
Upper reach of
Cell 2 at 0.5 %
slope
350 7.0 38.1 1.0 0.31
Middle reach of
Cell 2 at 1 %
slope
600 14.4 25.3 1.0 0.55
Lower reach of
Cell 2 at 0.5 %
slope
550 23.4 18.0 1.0 0.62
Cell 3 at 0.5 %
slope 830 35.0 13.1 1.0 0.70
Cell 4A at 0.8 %
slope 1200 47.0 10.2 1.0 0.83
Cell 4A side
slopes at 20%
slope
210 48.5 10.0 1.0 0.88
Note: Flow accumulates as it flows from Cell 2 to Cell 4A

The unit discharge values in Table G.1 above were used to evaluate the erosional stability of
the reclaimed surfaces and size erosion protection materials where necessary. These
evaluations are presented in Sections G.5 and G.6.

G.5 EROSIONAL STABILITY OF VEGETATED SLOPES
The surface of the reclaimed tailings disposal cells was evaluated for erosional stability using
the methods recommended in NRC (1990) and Johnson (2002).

Temple Method. Temple and others (1987) outlines procedures for grass-lined channel
design. These procedures are recommended in Johnson (2002) for areas of vegetated cover
and include methods for estimating stresses on channel vegetation as well as the channel
surface soils. The evaluation for the tailings disposal cells used the peak discharge values from
the PMP (summarized in Table G.1) to conservatively represent the effective stresses from
runoff on the cover surface. The stresses on both the vegetation and the soil were evaluated.

The erosional stability of the cover surface for the tailings disposal cells was evaluated by
calculating a factor of safety against erosion due to the peak runoff from the PMP. Factor-of-
safety values were calculated as the ratio of the allowable stresses (the resisting strength of the
cover vegetation or soils) to the effective stresses (the stresses impacted by the runoff flowing
over the cover). Two factors of safety were calculated for each analysis to evaluate both the
resistance of the vegetation, and the resistance of the silty topsoil layer. The peak unit
discharge flow for the tailings disposal cells (from Table G.1) was conservatively multiplied by a
concentration factor of 3 to account for channelization of flow.

Updated Tailings Cover Design Report
Denison Mines (USA) Corporation MWH Americas, Inc.
G-4 August 2012
AlIowable stresses. Allowable stresses for the cover soils were calculated using the equations
in Temple and others (1987). Material planned for the upper layer of the cover system is the on-
site stockpiled topsoil. Laboratory testing of the topsoil conducted in 2010 (see Appendix A)
indicates the topsoil classifies as either a silty clay with sand or a sandy silty clay. The D75
(diameter of which 75% of the material is finer) is approximately 0.08 mm to 0.1 mm (.003 in to
.004 in) with a plasticity index (PI) of approximately 4 to 7. The resistance of a silty soil with a PI
less than 10 is estimated to be approximately 0.02 psf (Temple et al., 1987). For noncohesive
soils with a D75 greater than 0.05 in., the resistance is calculated as follows:
0.4 , for soils with D75>0.05 in, 0.02, for noncohesive soils with D75≤0.05 in.

Where
a = allowable shear strength (psf), and
D75 = particle diameter in which 75 percent of the soil is finer (inch).

For areas where 1-inch gravel is added to the topsoil (25 percent by weight), the D75 of the
topsoil mixture will increase to approximately 0.2 inches.

As discussed in Appendix J of this report, the cover will be vegetated with a mixture of perennial
grasses (primarily wheatgrass, ricegrass, squirreltail, and fescue) and forbs (yarrow and sage).
The allowable vegetation shear strength is calculated as:
0.75

Where
va = allowable vegetation shear strength (in psf),
CI =cover index = 2.5 [h(M)1/2]1/3,
h = stem length (ft), and
M = stem density factor (stems per square ft).

Conservatively using poor vegetation conditions, h=1.0, M=67, and CI=5.03, the resulting
vegetation shear strength value is 3.78 psf.

Effective stresses. The effective shear stress on soil due to peak runoff from the PMP was
calculated as:
1 /

Where
e = effective shear stress (psf),
= unit weight of water = 62.4 pcf,
d = depth of flow (ft), from Table G-2,
S = slope of cover surface (ft/ft), from Table G-1,
Cf = cover factor (0.375 for poor vegetation),
ns = soil roughness factor (0.0156 for soils with D75≤0.05 in., or 0.0256(D75)1/6 for D75 >
0.05 in), and
n = Manning's roughness coefficient for vegetated surface.
.. ..

Updated Tailings Cover Design Report
Denison Mines (USA) Corporation MWH Americas, Inc.
G-5 August 2012

The effective shear stress on vegetation is calculated as:

Where
v = effective vegetal stress (psf).

Conservatively using poor vegetation conditions, the effective shear stresses on soil and
vegetation on the tailings cover surfaces are summarized in Table G.2.

Table G.2. Effective Shear Stresses on Soil and Vegetation
Location
Description
of
Erosion
Protection
Depth
of
Flow1
(ft)
Soil Vegetation
Effective
Shear
Stress
(psf)
Allowable
Shear
Stress
(psf)
Factor
of
Safety
Effective
Shear
Stress
(psf)
Allowable
Shear
Stress
(psf)
Factor
of
Safety
Cell 1 at
1% slope
Vegetation
and Gravel
(D75=0.2 in)
0.80 0.04 0.08 2.0 0.449 3.78 8.4
Cell 2 at
0.5 %
slope
Vegetation
(D75 = 0.003
in)
0.96 0.016 0.02 1.2 0.284 3.78 13.3
Cell 2 at
1 % slope
Vegetation
and gravel
(D75 = 0.2 in)
0.76 0.035 0.08 2.3 0.439 3.78 8.6
Cell 3 at
0.5 %
slope
Vegetation
(D75 = 0.003
in)
1.01 0.019 0.02 1.1 0.296 3.78 12.8
Cells 4A
and 4B at
0.8 %
slope
Vegetation
and gravel
(D75 = 0.2 in)
0.96 0.050 0.08 1.6 0.439 3.78 8.6
1 Calculated using a concentration factor of 3 for peak unit discharge

The calculated factors of safety above show that for poor vegetation conditions, the allowable
shear strengths are higher than the effective shear stresses on both the vegetation and the soil
during peak discharge from the PMP. When vegetation conditions are good or better, the soil
factor of safety improves significantly, while the vegetation factor of safety decreases slightly,
but remains well above 1.0. Further details of calculations can be found in Attachment G.2.

These analyses indicate that the cover on the top surface of the tailings disposal cells can be
constructed as a vegetated slope. Top slopes at 0.5 percent slopes are adequately stable
without the addition of gravel, while the 1 percent slope in Cell 2, and the 0.8 percent slope in
Cells 4A and 4B will require the addition of approximately 25% of 1-inch-minus gravel.

G.6 EROSIONAL STABILITY OF ROCK-PROTECTED SIDE-SLOPES
Because of the difficulty in maintaining vegetation on side slopes, the 5:1 side slopes have been
designed for erosional protection assuming vegetation is minimal. The maximum unit discharge
value from Table G.1 was used to size riprap for the embankment slopes. The Johnson and Abt

Updated Tailings Cover Design Report
Denison Mines (USA) Corporation MWH Americas, Inc.
G-6 August 2012
method referenced in Johnson (2002) was used for the side slopes. The required angular rock
size is calculated as follows:
5.23 ..

Where
D50 = median particle diameter of which 50 percent of the soil is finer (inch),
S = slope (ft/ft), and
qdesign = design flow (cfs/ft).

Flow Characteristics. The peak unit discharge values from Table G.1 were used to represent
flow conditions across the cover surface and down the embankment side slopes south of Cells
4A and 4B. Concentration factors of 3 were used to account for channelization of flow.

Rock Characteristics. A specific gravity of 2.65 was assumed for the riprap. The overall
erosion protection design uses rounded and angular rock for the embankment side slopes.
Angular rock was selected for slopes where the required minimum D50 for rounded rock was too
large to produce. For areas where rounded rock was selected, the minimum D50 was increased
by 40 percent in the design to account for rounded rock characteristics (Abt and Johnson,
1991). The results of the riprap sizing for the embankment slopes are summarized in Table G.3
below.

Table G.3. Results of Riprap Sizing
Location Design Unit
Discharge (cfs/ft)
Slope
(ft/ft)
Concentration
Factor
Median Rock
Size (inches)
Non-Accumulating Side Slopes
(Rounded Rock) 0.06 0.20 3 1.7
Cell 4A and 4B southern side
slopes(Angular Rock) 0.86 0.20 3 5.3
Cell 1 Disposal Area side slope
(Angular Rock) 0.64 0.20 3 4.5

Filter Requirements. NUREG-1623 (Johnson, 2002) recommends a filter or bedding layer be
placed under the erosion protection if interstitial velocities are greater than 1 ft/s, in order to
prevent erosion of the underlying soils. Bedding is not required if interstitial velocities are less
than 0.5 ft/s, and are recommended depending on the characteristics of the underlying soil if
velocities are between 0.5 and 1.0 ft/s.

Interstitial velocities are calculated by procedures presented by Abt et al. (1991) as given in the
following equation: 0.23 .

Where
Vi = interstitial velocities (ft/s),
G = acceleration due to gravity (ft/s2),
D10 = stone diameter at which 10 percent is finer (inches), and
S = gradient in decimal form.

The maximum D10 of the erosion protection is estimated based on the D50 required for erosion
protection, assuming the erosion protection will have a coefficient of uniformity (CU) of 6 and a
band width of 5. Band width refers to the ratio of the minimum and maximum allowed particle

Updated Tailings Cover Design Report
Denison Mines (USA) Corporation MWH Americas, Inc.
G-7 August 2012
sizes acceptable for any given percent finer designation. USDA (1994) recommends CU to be a
maximum of 6 in order to prevent gap-grading of filters. Table G.4 summarizes the results for
the side slopes.

Table G.4. Results of Filter Requirements for Side Slopes
Location
Non-Accumulating Side
Slopes (Rounded Rock)
Cell 4A and 4B southern
side slopes(Angular
Rock)

Cell 1 Disposal Area
side slope (Angular
Rock)
Minimum D50 (inches) 1.7 5.3 4.5
Maximum D10
(inches) 0.53 1.64 1.39
Slope (%) 20 20 20
Interstitial Velocity
(ft/s) 0.43 0.75 0.69
Filter Requirement No Recommended Recommended

Based on the results in Table G.4 and the fine-grained nature of the top soil, it is recommended
that a filter be placed between the soil and the rock protection for the side slope areas that
require angular riprap. These areas include the southern side slopes of Cells 4A and 4B as well
as the northern side slope of the Cell 1 disposal area as shown in Figure G.1. The interstitial
velocity results confirm that a filter is not necessary for the non-accumulating side slopes where
rounded rock is proposed on the west and east sides of Cells 2, 3 and 4.

Gradation for proposed Filter. The procedure from USDA (1994) for determining the
gradation limits for a sand or gravel filter was used to evaluate the type of material needed to
satisfy filter requirements between the soil and rock protection for the side slopes. The method
details twelve steps to determine an appropriate gradation range for the filter layer. The steps
can be found in Chapter 26 of the USDA Handbook and are shown in the Attachment G.2 for
supporting calculations. In addition, Equation 5.3 from Cedegren (1989) and Equation 4.36 from
Nelson et al. (1986) were used to determine the filter gradation requirements. and Table G.5
presents the recommended gradation.

Table G.5. Results of Filter Gradation Requirements
Diameter
(mm)
Sieve
Sizes
Percent
Passing
76.2 3" 100
4.75 No. 4 70-100
0.85 No. 20 40-60
0.075 No. 200 0-5

Based on the results of Table G.5, the filter material should be a medium sand that will be
placed between the erosion protection and the base layer on the side slopes.

Sheet Erosion. The Modified Universal Soil Loss Equation (MUSLE) as presented in
NUREG/CR4620 (Nelson et al., 1986) was used to evaluate the potential for soil loss due to
sheet flows across the gravel/topsoil surface layer of the cover.

Updated Tailings Cover Design Report
Denison Mines (USA) Corporation MWH Americas, Inc.
G-8 August 2012
The MUSLE is defined as: ∗ ∗ ∗

Where:
A = soil loss, in tons per acre per year,
R = rainfall factor,
K = soil erodibility factor,
LS = topographic factor, and
VM = dimensionless erosion factor relating to vegetative and mechanical factors

The rainfall factor, R, is 30, as given in NUREG/CR-4620 for the eastern third of Utah. The soil
erodibility factor, K, was estimated to be 0.28 for the topsoil and 0.16 for the gravel and topsoil
mixture, based on the nomograph (Fig. 5.1) in NUREG/CR-4620.

The topographic factor, LS, is calculated based on the following equation:
650 450 65
10,000
∗ 72.6

Where:
s = slope steepness, in percent (%),
L = slope length in feet,
m = slope steepness dependent exponent

The topographic factor was calculated using a slope of 0.82% and a slope length of 1,300 feet.
From the Table 5.2 in NUREG/CR-4620, the slope steepness exponent, m, is 0.2 for slopes less
than or equal to 1.0%.

The erosion factor, VM, used was 0.4, from Table 5.3 of NUREG/CR-4620, to represent
seedlings of 0 to 60 days, to mimic light vegetation on the cover. Table G.5 summarizes the
MUSLE results for the proposed topsoil and the proposed topsoil mixed with 25% gravel, by
weight.

Table G.6. Results of MUSLE
Soil Cover Proposed Topsoil Proposed Topsoil with
25% Gravel
Rainfall factor, R 30 30
Silt and very fine sand (%) 43.6 32.7
Sand (%) 39.2 29.4
Organic matter (%) 1.5 1.5
Soil structure Fine granular Medium or coarse granular
Relative permeability Moderate Moderate to rapid
Erodibility factor, K 0.28 0.12
Topographic Factor, LS 0.16 0.19
Erosion factor, VM – low density seedings 0.4 0.4
Soil loss (tons/acre/year) 0.54 0.27
Soil loss (inches/1,000 years) 3.0 1.5

The soil loss equation shows the potential for erosion will be reduced by almost one half, by
using 25% gravel in the topsoil mixture. The topsoil loss of 1.5 to 3.0 inches over the life of the
cover (1,000 years) is less than the minimum design thickness of 6 inches.

Updated Tailings Cover Design Report
Denison Mines (USA) Corporation MWH Americas, Inc.
G-9 August 2012
G.7 ROCK SIZING FOR APRON
Additional erosion protection will be provided for runoff from the south side slopes of the
reclaimed surfaces of Cells 4A and 4B, the east side of Cell 4A, and the north side of Cell 1 with
a rock apron. The perimeter apron will: (1) serve as an impact basin and provide for energy
dissipation of runoff, (2) provide erosion protection, and (3) transition flow from side slopes to
natural ground. The median rock size required in the perimeter apron was calculated using the
equations derived by Abt et al. (1998) as outlined in NUREG 1623 (Johnson, 2002) as follows:

10.46 ..

Flow Characteristics. The peak unit discharge values from Table G.1 were used to represent
flow conditions down the embankment side slopes south of Cells 4A and 4B. Concentration
factors of 3 were used to account for channelization of flow.

Rock Characteristics. A specific gravity of 2.65 was assumed for the riprap. Both rounded and
angular rock was used in the apron design.

Based on the above equation, the rock apron (Apron A) along the toe of the non-accumulating
slopes covered with rounded riprap (west and east side slopes of Cells 2 and 3) should be
constructed using rounded rock with a median rock diameter of 3.4 inches. The width of the
apron should be a minimum of 15 times the median rock size (4.25 ft) and the apron thickness
should be a minimum of three times the median rock size (10.2 inches). Rock Apron B should
be placed on the toes of the south slope of Cells 4A and 4B and along the east of Cell 4A, .
Apron B should have a median angular rock size of 10.6 inches, with a minimum width of 13.2
feet and a minimum thickness of 2.7 feet. Rock Apron C should be placed on the toes of the
remaining slope (Cell 1 disposal area side slope). Apron C should have a median rock size of
9.0 inches, a minimum width of 11.3 feet, and a minimum thickness of 2.3 feet.

Filter Requirements. NUREG-1623 (Johnson, 2002), as detailed in section G.6, was used to
determine if a bedding layer was required for the rock aprons. The results are presented in
Table G.7 below.

Table G.7. Results of Filter Requirements for Rock Aprons
Location
Apron A: Non-
Accumulating
Slopes (Rounded)
Apron B: Cell 4A and 4B
slopes(Angular)
Apron C: Cell 1 disposal
area side slope
(Angular)
Minimum D50
(inches) 3.4 10.6 9.0
Maximum D10
(inches) 1.0 3.3 2.8
Slope (%) 1 1 1
Interstitial Velocity
(ft/s) 0.13 0.24 0.22
Filter Requirement No No No

Based on the results in Table G.7, it is not required to place a bedding layer between the soil
and rock protection for the rock aprons.

Updated Tailings Cover Design Report
Denison Mines (USA) Corporation MWH Americas, Inc.
G-10 August 2012
G.8 DISCHARGE CHANNEL AND SEDIMENTATION BASIN
The PMP event described in section G.3 was used to determine the peak discharge to the
channel to be located at the west end of the sedimentation basin. The peak discharge
calculations were made using the Rational Method and the time of concentration was calculated
for the longest flow path (see Figure G.1) across the mill site and sedimentation basin using the
procedures described in section G.4. A runoff coefficient of 1.0 was used to represent PMP
conditions (DOE, 1989). These characteristics represent high runoff quantities and peak flow
velocities.

The PMP peak discharge calculated across the mill site and sedimentation basin is presented in
Table G.8. This discharge represents the peak flow into the channel. Further details of the
calculations can be found in Attachment G.1

Table G.8. Peak Discharge Flow to the Discharge Channel
Location
Slope
Length
(feet)
Time of
Concentration
(min)
Rainfall
Intensity
(in/hr)
Runoff
Coefficient
Peak
Discharge
(cfs)
Mill site and
sedimentation
basin
4,600 26.3 16.4 1.0 2,440

The peak discharge value in Table G.8 above, was used to evaluate the peak flow velocities
through the discharge channel excavated into bedrock. The channel dimensions are shown on
Drawing REC-3 and include a 150-foot bottom width and 3:1 (H:V) side slopes. The Manning’s
n-value was estimated and adjusted based on the anticipated type of bedrock and the
presumed roughness, along the channel, after excavation. Table G.9 includes peak flow
velocities for Manning’s n-values of 0.02 and 0.03.

Table G.9. Peak Discharge Channel Flow Velocities
Location
Channel
Bottom
Width
(feet)
Channel
Side
Slopes
(H:V)
Manning
Coefficient,
n
Flow
Depth
(ft)
Cross
Sectional
Area of
Flow (ft2)
Hydraulic
Radius
(ft)
Peak
Velocity
(fps)
Discharge
channel 150 3:1 0.02 1.67 259 1.61 9.4
Discharge
channel 150 3:1 0.03 2.12 332 2.03 7.3

Based on the available bedrock information near the channel location, the rock is expected to
consist of a fine to medium-grained sandstone with varying degrees of cementation and
weathering, or a claystone (Dames and Moore, 1978). The shear wave velocities from seismic
refraction surveys indicate the bedrock will range from rippable to hard rock, requiring blasting
(D’Appolonia, 1979). Because of this variability, an initial Manning’s n-value of 0.015 was
selected, for a channel in rock and then modifications of 0.005 and 0.015 were added for
increasing irregularities in the final excavated rock surface. (USBR, 1987). Maximum suggested
permissible peak channel velocities are 10 feet per second for channels excavated in “poor
rock” (USACE, 1994).

Updated Tailings Cover Design Report
Denison Mines (USA) Corporation MWH Americas, Inc.
G-11 August 2012
G.9 REFERENCES
Abt, S., Ruff, J., and Wittler, R., 1991. Estimating Flow Through Riprap, Journal of Hydraulic
Engineering, Vol. 117, No. 5, May.

Abt, S., and Johnson, T. 1991. Riprap Design for Overtopping Flow, Journal of Hydraulic
Engineering, Vol. 117, No. 8, August.

Cedegren, H.R., 1989. Seepage, Drainage, and Flow Nets. Equation 5.3. 3rd Edition. John
Wiley & Sons, Inc., New York.

Dames and Moore, 1978. Site Selection and Design Study - Tailing Retention and Mill Facilities
White Mesa Uranium Project. January 17.

D’Appalonia, 1979. Tailings Management System, White Mesa Uranium Project, Blanding Utah.
June.

Denison Mines (USA) Corporation (Denison), 2009. “Re: Cell 4B Lining System Design Report,
Response to DRC Request for Additional Information – Round 3 Interrogatory, Cell 4B
Design – Exhibit C: Probable Maximum Precipitation (PMP) Event Calculation”, Letter to
Dane Finerfrock, September 11.

Denison Mines (USA) Corporation (Denison), 2012. Responses to Interrogatories – Round 1 for
Reclamation Plan, Revision 5.0, March 2012; Attachment B: Updated Probable
Maximum Precipitation (PMP) Calculation. May 31.

Hansen, E. M., Schwarz, F.K., Riedel, J.T., 1984. “Hydrometeorological Report No. 49:
Probable Maximum Precipitation Estimates, Colorado River and Great Basin Drainages,”
Hydrometeorological Branch Office of Hydrology, National Weather Service, U.S.
Department of Commerce, National Oceanic and Atmosphere Administration, U.S.
Department of the Army, Corps of Engineers, Silver Springs, MD.

Jensen, D. 1995. Final Report: Probable Maximum Precipitation Estimates for Short Duration,
Small Area Storms in Utah, October.

Johnson, T.L., 2002. "Design of Erosion Protection for Long-Term Stabilization." U.S. Nuclear
Regulatory Commission (NRC), NUREG-1623. September.

MWH, Inc. (MWH), 2010. Revised Infiltration and Contaminant Transport Modeling Report,
White Mesa Mill Site, Blanding, Utah, prepared for Dension Mines, March.

Nelson, J., S. Abt, R. Volpe, D. van Zyl, N. Hinkle, and W. Staub, 1986. "Methodologies for
Evaluation of Long-term Stabilization Designs of Uranium Mill Tailings Impoundments."
NUREG/CR-4620, U.S. Nuclear Regulatory Commission, June.

Temple, D.M., K.M. Robinson, R.A. Ahring, and A.G. Davis, 1987. "Stability Design of Grass-
Lined Open Channels." USDA Handbook 667.

U.S. Army Corps of Engineers, 1994. Hydraulic Design of Flood Control Channels, EM 1110-2-
1601. p.2-16. June.

Updated Tailings Cover Design Report
Denison Mines (USA) Corporation MWH Americas, Inc.
G-12 August 2012
U.S. Department of Agriculture (USDA), 1994. Gradation Design of Sand and Gravel Filters,
National Engineering Handbook, Part 633, Chapter 26, October.

U.S. Department of Energy (DOE), 1989. Technical Approach Document, Revision II, UMTRA-
DOE/AL 050425.0002, Uranium Mill Tailings Remedial Action Project, Albuquerque,
New Mexico.

U.S. Department of the Interior, Bureau of Reclamation (USBR), 1987. Design of Small Dams.
3rd Edition. p.595.

U.S. Nuclear Regulatory Commission (NRC), 1990. "Final Staff Technical Position, Design of
Erosion Protective Covers for Stabilization of Uranium Mill Tailings Sites," August.

Updated Tailings Cover Design Report

ATTACHMENT G.1

PMP CALCULATIONS
DENISON (2012)
DENISON (2009)

Client: Denison Mines Job No.: 1009740
Project: White Mesa Reclamation Plan Date: 5/10/2012
Detail: Updated Probable Maximum Precipitation (PMP) Calculation Computed By: MMD
References:
Denison Mines (USA) Corporation (Denison), 2009. Re: Cell 4B Lining System Design Report, Response to DRC Request for Additional
Information – Round 3 Interrogatory, Cell 4B Design – Exhibit C: Probable Maximum Precipitation (PMP) Event Calculation, Letter to
Dane Finerfrock, September 11.
Hansen, E. M., Schwarz, F.K., Riedel, J.T., 1984. Hydrometeorological Report No. 49: Probable Maximum Precipitation Estimates,
Colorado River and Great Basin Drainages, Hydrometeorological Branch Office of Hydrology, National Weather Service, U.S. Department
of Commerce, National Oceanic and Atmosphere Administration, U.S. Department of the Army, Corps of Engineers, Silver Springs, MD.
Jensen, D. 1995. Final Report: Probable Maximum Precipitation Estimates for Short Duration, Small Area Storms in Utah, October.
Jensen, D., 2003. 2002 Update for Probable Maximum Precipitation, Utah 72 Hour Estimates to 5,000 sq. mi., March.
Utah Division of Radiation Control (DRC), 2012. Denison Mines (USA) Corp's White Mesa Reclamation Plan, Rev. 5.0, Interrogatories -
Round 1, March.
Approach:
Update previous calculations (Denison, 2009) to incorporate Jensen (1995) and Jensen (2003) references as recommended by DRC (2012)
Jensen (2003) is applicable for 72-hour durations for areas up to 5,000 square miles. Incorporation of this reference does not modify
the previous calculations for one-hour or six-hour duration PMP values for the site.
Calculations:
Site Information
Parameter Value Units
Drainage Area 0.4 mi2
Latitude N 37ο31'
Longitude W 109o30'
Minimum Elevation 5600 ft
Updated Local-Storm PMP Estimates
Parameter Value Units
One-hour point precipitation PMP value 8.6 in
Elevation Reduction 97 %
One-Hour PMP (adjusted for elevation) 8.3 in
6-hr to 1-hr Depth Percentage 115 %
Six-Hour PMP 9.6 in
Areal Reduction 100 %
RESULTS
One-Hour Duration PMP 8.3 in
Six-Hour Duration PMP 9.6 in
Updated Local-Storm PMP Incremental Values
Duration (hr)
Percentage of
1-hr PMP
Depth
(in)
Incremental
Depth (in)
0.25 50 4.2 4.2
Hourly
Increments Depth (in)
15-Min.
Increments Depth (in)
0.5 74 5.5 1.3 1st 0.1 1st 4.2
0.75 90 7.5 2.0 2nd 0.2 2nd 2.0
1 100 8.3 0.8 3rd 8.3 3rd 1.3
2 110 9.1 0.8 4th 0.8 4th 0.8
3 112 9.3 0.2 5th 0.1
4 113.5 9.4 0.1 6th 0.1
5 114.5 9.5 0.1
6 115 9.6 0.1
Denison (2009)
Denison (2009)
Denison (2009) for Cells 2 through 4B
Comments
One-Hour Duration PMPSix-Hour Duration PMP
Comments
Jensen (1995) references Figure 4.7 in Hansen (1984).
Denison (2009)
Jensen (1995) recomments same elevation reduction as used in Hansen (1984).
This is the same value presented in Denison (2009)
Table 15 in Jensen (1995)
One-hour PMP multiplied by 6-hr to 1-hr depth percentage
Table 15 in Jensen (1995) for 1 sq. mi. area
L:\Denison Mines\6.0 Studies & Reports\6.2 Technical\6.2.1 Calculations\Erosion Protection\Erosion Protection(5-10-12)_mmd.xlsx

EXHIBIT C

PROBABLE MAXIMUM
PRECIPITATION (PMP)
EVENT CALCULATION
PACKAGE

Page 1 of 5

Written by: M. Lithgow Date: 09/04/09 Reviewed by: G. Corcoran Date: 9/10/09

Client: DMC Project: White Mesa Mill-
Cell 4B
Project/
Proposal No.:
SC0349 Task
No.:
02

PMP Calc 20090910Fcalc.doc
PROBABLE MAXIMUM PRECIPITATION (PMP) EVENT COMPUTATION
WHITE MESA MILL – CELL 4B
BLANDING, UTAH
OBJECTIVE
The purpose of this calculation is to evaluate the local-storm Probable Maximum
Precipitation (PMP) event for the White Mesa Mill Facility site located in Blanding,
Utah. This calculation demonstrates that the probable maximum precipitation (PMP)
event that the site will experience is 10 inches (0.83 ft) in 6 hours.
PMP COMPUTATION PROCEDURE
The Probable Maximum Precipitation (PMP) for the site was evaluated using
“Hydrometeorological Report No. 49: Probable Maximum Precipitation Estimates,
Colorado River and Great Basin Drainages” (Hansen, et. al., 1984). The use of this
method is cited in a hydrology report that was prepared as part of an agreement between
UMETCO and the Nuclear Regulatory Commission (NRC) during the permitting of
Cell 4A (UMETCO, 1990).
PROBABLE MAXIMUM PRECIPITATION EVENT CALCULATIONS
Step 1: Calculate the Average 1-hr 1-mi2 PMP for drainage using Figure 4.5

The average 1-hr 1-mi2 PMP is 8.6-in (Attachment A, 1/7)

Step 2a: Reduce the 1-hr 1-mi2 PMP event for elevation

If the lowest elevation within the drainage is above 5,000 feet (ft) above Mean Seal
Level (MSL), decrease the PMP value from Step 1 by 5% for each 1,000 ft or
proportionate fraction thereof above 5,000 ft to obtain the elevation adjusted drainage
average 1-hr 1-mi2 PMP.

The elevation of Cell 4B is 5,598 ft above MSL, which is conservatively the lowest
elevation for the completed cells 2 through 4B; therefore, it is required to interpolate

Page 2 of 5

Written by: M. Lithgow Date: 09/04/09 Reviewed by: G. Corcoran Date: 9/10/09

Client: DMC Project: White Mesa Mill-
Cell 4B
Project/
Proposal No.:
SC0349 Task
No.:
02

PMP Calc 20090910Fcalc.doc
between 95% and 100% using the following equation:
ft
x
ft 598
%
000,1
%5 =; x = 3% reduction

100 % - 3 % = 97 %

Therefore, reduce the value obtained in Step 1 by 97%.

Step 2b: Multiply the number calculated in Step 1 by the number calculated in Step 2a.

8.6 inches x 0.97 = 8.3 inches

Step 3: Determine the average 6/1-hr ratio for drainage using Figure 4.7

The average 6/1-hr ratio for drainage is approximately 1.2. (Attachment A, 2/7)

Step 4: Calculate the durational variation for 6/1-hr ratio of Step 3 using Table 4.4

The durational value is determined using Table 4.4 is as follows: (Attachment A, 3/7)

Duration (hr)
¼ ½ ¾ 1 2 3 4 5 6
74 89 95 100 110 115 118 119 120 %

Step 5: Multiply step 2b by Step 4 to calculate the 1-mi2 PMP for indicated durations

For example, for the ¼ hour duration: 8.3 x 0.74 = 6.1

The following numbers are calculated as follows:

Duration (hr)
¼ ½ ¾ 1 2 3 4 5 6
6.1 7.4 7.9 8.3 9.1 9.5 9.8 9.9 10.0 in.

Step 6: Determine the areal reduction using Figure 4.9 for the site:

Page 3 of 5

Written by: M. Lithgow Date: 09/04/09 Reviewed by: G. Corcoran Date: 9/10/09

Client: DMC Project: White Mesa Mill-
Cell 4B
Project/
Proposal No.:
SC0349 Task
No.:
02

PMP Calc 20090910Fcalc.doc
First, determine the total watershed contributing to Cell 4B, including Cell 4B. The
watershed areas of the upstream Cells 2, 3, and 4A are 87 acres (ac), 83 ac, and 40 ac,
respectively and the proposed Cell 4B is 42 ac. Areas outside of these cells do not drain
to Cell 4B and are therefore not part of the watershed area.

Total acreage is 87 ac + 83 ac + 42 ac + 42 ac = 254 acres.
Next, convert this number into square miles:

2
2
2
40.0)280,5(
)1(
1
560,43254 2 mift
mixacre
ftxacre =

Using Figure 4.9, the depth ratio of ≤1 mi2 is 100 percent for each of the durations
(Attachment A, 4/7).

Step 7: Multiply the duration values in Step 5 by the areal reduction in Step 6 to
calculate the areal reduced PMP.

This step is neglected because the depth ratio is 100 percent; therefore, the values
obtained in Step 5 are not reduced.

Step 8: Calculate the incremental PMP using successive subtraction of the values in
Step 7 for the hourly durations (1 hr through 6 hr) and 15-minute incremental durations
(1/4 hr through 1 hr).

The incremental PMP is calculated in two separate steps; the incremental PMP is
calculated on the first line for the hourly increments (hours 1 through 6) and then
calculated on the second line for the 15-minute increments during the first hour of the
storm. To determine the incremental PMP, the following formula is used:
ttttotPMPPMPPMP−=++11 , where t = time
In this example, the PMP between the first interval and second interval is determined by
subtracting the PMP for interval 1 from the PMP for the second interval, as calculated
in Step 5. The following equation illustrates the calculation of the incremental PMP
between hours 0 and 1:

Page 4 of 5

Written by: M. Lithgow Date: 09/04/09 Reviewed by: G. Corcoran Date: 9/10/09

Client: DMC Project: White Mesa Mill-
Cell 4B
Project/
Proposal No.:
SC0349 Task
No.:
02

PMP Calc 20090910Fcalc.doc

=−01PMPPMP 8.3 in – 0 in. = 8.3 in.
The next equation illustrates the calculation of the incremental PMP between hours 1
and 2:

=−12PMPPMP 9.1 in – 8.3 in. = 0.8 in.

This calculation is continued until the following table is completed as shown for each
PMP interval.

Duration (hr)
¼ ½ ¾ 1 2 3 4 5 6
8.3 0.8 0.4 0.2 0.1 0.1 in.
6.1 1.2 0.5 0.4 in.

Step 9: Order the incremental PMP in a sequence dictated by hourly and 15-minute
increments using Table 4.7 (Attachment 5/7) and Table 4.8 (Attachment 6/7),
respectively.

The incremental PMP calculated in Step 8 must now be arranged in a specific order to
model the runoff generated by the storm event. This order is dictated by Table 4.7 for
the hourly PMP intervals and Table 4.8 for the 15-minute PMP intervals.

The final arrangement of the numbers determined in Step 8 is as follows:

Hourly increments: 0.1 0.4 8.3 0.8 0.2 0.1 in.
15-minute increments: 6.1 1.2 0.5 0.4 in.

The storm’s 6 hour PMP runoff event is calculated by summing the incremental PMP
for each hour of the storm.
0.1 in. + 0.4 in. + 8.3 in. + 0.8 in. + 0.2 in. + 0.1 in. = 9.9 inches (10 inches).

This step is repeated to calculate the runoff generated during the first hour of the storm.
6.1 in. + 1.3 in. + 0.5 in. + 0.4 in. = 8.3 inches

Page 5 of 5

Written by: M. Lithgow Date: 09/04/09 Reviewed by: G. Corcoran Date: 9/10/09

Client: DMC Project: White Mesa Mill-
Cell 4B
Project/
Proposal No.:
SC0349 Task
No.:
02

PMP Calc 20090910Fcalc.doc

Because 9.9 > 8.3, the runoff generated from the 6 hour storm (9.9 inches) is used.
CONCLUSIONS AND RECOMMENDATIONS
Our calculations are summarized in a worksheet modeled after Table 6.3A in the
Hydrometerological Report No. 49 and is provided as Attachment A, 7/7. Our analysis
determined the Probable Maximum Precipitation (PMP) event generates 10 inches (0.83
ft) over 6 hours.
REFERENCES
UMETCO Minerals Corporation, 1990, “White Mesa Mill Drainage Report for
Submittal to NRC.”

Attachment A

Hansen, E. Marshall, Schwartz, Francis K., Riedel, John T., 1984.
“Hydrometeorological Report No. 49: Probable Maximum Precipitation
Estimates, Colorado River and Great Basin Drainages,” Hydrometeorological
Branch Office of Hydrology National Weather Service, U.S. Department of
Commerce, National Oceanic and Atmosphere Administration, U.S. Department
of Army Corps of Engineers, Silver Springs, Md.

Area mi2
Latitude: N 37° 31'Longitude: W 109° 30' Min. Elevation 5598 ft
1 Average 1-hr 1-mi2 (2.6-km2) PMP for
drainage [fig. 4.5]8.6 in.
2a.
Reduction for Elevation. [No adjustment for
elevations up to 5,000 feet: 5% decrease per
1,000 feet above 5,000 feet.0.97 %
b.Multiply step 1 by step 2a.8.3 in.
3.Average 6/1-hr ratio for drainage [fig 4.7]1.2
1/41/23/4123456
4 Durational variation for 6/1-hr ratio of step 3
[table 4.4]74 89 95 100 110 115 118 119 120 %
5 1-mi2 (2.6 km2) PMP for indicated durations
[step 2b x step 4]6.1 7.4 7.9 8.3 9.1 9.5 9.8 9.9 10.0
6 Areal reduction [fig. 4.9]100 100 100 100 100 100 100 100 100 %
7 Areal reduced PMP [steps 5 x 6 ]6.1 7.4 7.9 8.3 9.1 9.5 9.8 9.9 10.0 in.
8 Incremental PMP [successive subtraction in
step 7]8.3 0.8 0.4 0.2 0.1 0.1 in.
6.1 1.2 0.5 0.4 } 15-min. increments
9 Time sequence of incremental PMP to:
Hourly increments [table 4.7]0.1 0.4 8.3 0.8 0.2 0.1 in.
9.9 in.
Four largest 15-min increments [table 4.8]6.1 1.2 0.5 0.4 in
Total depth of 1st hour of storm 8.3 in.
Duration (hr)
Table 6.3A -- Local-storm PMP computation, Colorado River, Great Basin and California drainages. For drainage average depth PMP.
Total depth of 6 hour storm
0.39Drainage: White Mesa Mill Facility, Cells 2 - 4B
PMP Calculation.xlsx Attachment A, 7/7

Updated Tailings Cover Design Report

ATTACHMENT G.2

SUPPORTING CALCULATIONS

Client:Denison Mines Job No.: 1009740
Project:White Mesa Reclamation Plan Date:5/31/2011
Detail:Erosion Protection Computed By:RTS
PMP Event
PMP calculation from "Re: Cell 4B Lining System Design Report, Response to DRC Request fo Additional
Information - Round 3 Interrogatory, Cell 4B design", September 11,2009.
Procedure: Hydrometeorological Report No. 49: Probable Maximum Precipitation Estimates, Colorado river and Great Basin Drainages
(Hansen et al., 1984), corrected for elevation and area.
Table 1. Estimated Precipitation Depths For Local-Storm PMP, White Mesa Mill, Utah Site
Hourly Increments
First
Hour Second Hour
Fourth
Hour
Fifth
Hour
Sixth
Hour
PMP Depths (inches)
0.1 0.2 0.8 0.1 0.1
Third-Hour
Component Depths
(inches)4.2 2.0 1.3 0.8
Third Hour
8.3
0
1
2
3
4
5
6
7
8
9
0 10 20 30 40 50 60
Pr
e
c
i
p
i
t
a
t
i
o
n

(
i
n
c
h
e
s
)
Duration (min)
Depth-Duration
Erosion Protection(7-26-12):PMP
Attachment G.2
Client:Denison Mines Job No.: 1009740
Project:White Mesa Reclamation Plan Date:7/28/2012
Detail:Erosion Protection Computed By:TMS
Time of Concentration
1-hour PMP (in) 8.3
Flow Path 1: flow path across longest 5H:1V side slope in Cell 4A
Kirpich SCS
Brant and
Oberman Average
Cell 2 at 0.5% 0.005 530 7.5 7.5 11.5 8.9 60.1 4.99 33.8
Cell 3 top 0.005 870 18.5 18.5 25.2 20.7 81.9 6.80 19.7
Cell 4A top 0.0082 1200 30.2 30.2 38.0 32.8 91.0 7.55 13.8
Cell 4A side slope 0.2 210 31.0 31.1 40.5 34.2 91.7 7.6 13.3
Note: Flow accumulates as it flows from Cell 2 to Cell 4A. Design flow path is longest path across maximum 5H:1V side slope
Flow Path 2: longest flow path across cells with .82% top slope across cells 2, 3, 4A and 4B
Kirpich SCS
Brant and
Oberman Average
Cell 2 at 0.5% 0.005 350 5.5 5.5 10.1 7.0 53.4 4.44 38.1
Cell 2 at 1% 0.01 600 11.8 11.8 19.6 14.4 73.2 6.07 25.3
Cell 2 at 0.5% 0.005 550 19.5 19.5 31.3 23.4 84.6 7.02 18.0
Cell 3 top 0.005 830 30.1 30.2 44.7 35.0 92.1 7.64 13.1
Cell 4A top 0.0082 1200 41.8 41.8 57.6 47.0 96.5 8.01 10.2
Cell 4A side slope 0.2 210 42.7 42.7 60.0 48.5 96.9 8.0 10.0
Note: Flow accumulates as it flows from Cell 2 to Cell 4A. Design flow path is longest path across Cell 2, 3, and 4A,
and not the longest flow path across each individual cell
Cell 2 and Side slopes that only drain area of slope
Kirpich SCS
Brant and
Oberman Average
Cell 2 Top 0.5%
Slope 0.005 360 5.6 5.6 10.1 7.1 53.9 4.5 37.8
Cell 2 Top 1%
Slope 0.01 600 11.9 11.9 19.7 14.5 73.4 6.1 25.2
Cell 2 Northern
.5% Slope 0.005 600 20.2 20.2 31.7 24.0 85.1 7.1 17.6
Cell 1 Disposal
1% Slope 0.01 168 22.5 22.6 38.0 27.7 87.9 7.3 15.8
Cell 2 Northern
Side Slope 0.2 96 23.0 23.1 39.9 28.7 88.5 7.3 15.4
Non-Accumulating
Side Slopes 0.2 50 0.3 0.3 1.5 2.5 27.5 2.3 54.8
Note: These are the slopes on the sides of Cells 4A, 4B, 3, and 2
Flow Path 3: Flow Path Across Cell 1
Kirpich SCS
Brant and
Oberman Average
Cell 1 at .1%0.001 2232 42.2 42.3 31.9 38.8 93.7 7.8 12.0
Source: Brant and Oberman(1975) as presented in UMTRA TAD (1989)
Formula: tc=C(L/Si^2)^(1/3).
Source:Kirpich (1940) as presented in NUREG 4620
Formula: tc=0.00013*L^0.77/S^0.385 with L in feet, tc in hours
Source: SCS as presented in NUREG 4620
Formula: tc=(11.9L^3/H)^0.385 with L in miles, H in feet, t in hours
% of one-hour PMP=RD/(0.0089*RD+0.0686) for tc<15 min based on Table 4.1 of TAD
Cell geometry based on Figure A-5.1-1 Reclamation Plan Reve 3.2, March, 2010
PDPMP (in)
Intensity
(in/hr)
Description
Slope
(feet/feet)
Slope
Length
(feet)
Time of Concentration (minutes)
% of 1-hour
PMP PDPMP (in)
Intensity
(in/hr)
Description
Slope
(feet/feet)
Slope
Length
(feet)
Time of Concentration (minutes)
% of 1-hour
PMP
Description
Slope
Length
(feet)
Time of Concentration (minutes)
% of 1-hour
PMP
Description
Slope
(feet/feet)
Slope
Length
(feet)
Time of Concentration (minutes)
% of 1-hour
PMP PDPMP (in)
PDPMP (in)
Slope
(feet/feet)
Intensity
(in/hr)
Intensity
(in/hr)
Erosion Protection(7-26-12):Time of concentration
Attachment G.2
Client:Denison Mines Job No.: 1009740
Project:White Mesa Reclamation Plan Date:7/28/2012
Detail:Erosion Protection Computed By:TMS
Unit discharge of PMP
Flow Path 1: flow path across longest 5H:1V side slope in Cell 4A
Cell 2 at 0.5% 530 1 8.9 33.8 0.41
Cell 3 top 1400 1 20.7 19.7 0.63
Cell 4A top 2600 1 32.8 13.8 0.82
Cell 4A side
slope
2810
1 34.2 13.3 0.86
Note: Flow accumulates as it flows from Cell 2 to Cell 4A
Flow Path 2: longest flow path across cells with 0.8% top slope across cells 4A and 4B
Cell 2 at 0.5% 350 1 7.0 38.1 0.31
Cell 2 at 1% 950 1 14.4 25.3 0.55
Cell 2 at 0.5% 1500 1 23.4 18.0 0.62
Cell 3 top 2330 1 35.0 13.1 0.70
Cell 4A top 3530 1 47.0 10.2 0.83
Cell 4A side
slope
3740
1 47.0 10.2 0.88
Note: Flow accumulates as it flows from Cell 2 to Cell 4A
Side Slope Flow Paths
Cell 2 Top 0.5%
Slope 360 1 7.1 37.8 0.31
Cell 2 Northern
1% Slope
960
1 14.5 25.2 0.56
Cell 2 Northern
.5% Slope
1560
1 24.0 17.6 0.63
Cell 1 Disposal
1% Slope
1728
1 27.7 15.8 0.63
Cell 1 Disposal
Side Slope
1824
1 28.7 15.4 0.64
Non-
Accumulating
Side Slopes
50
1 2.5 54.8 0.06
Cell 1 at .1%2232 1 38.8 12.0 0.62
Cell 2 at 0.5%350 1 7.0 38.1 0.31
Cell 2 at 1%950 1 14.4 25.3 0.55
Cell 2 at 0.5%1500 1 23.4 18.0 0.62
Cell 2 - Cell 3
transition slope 1550 1 24.2 17.6 0.62
unit
discharge Description
Total Drainage
Length (ft) C Tc (min)
Intensity
(in/hr)
unit
discharge
(cfs/ft)
Description
Total Drainage
Length (ft) C Tc (min)
Intensity
(in/hr)
unit
discharge
(cfs/ft)
Description
Total Drainage
Length (ft) C Tc (min)
Intensity
(in/hr)
unit
discharge Description
Total Drainage
Length (ft) C Tc (min)
Intensity
(in/hr)
Erosion Protection(7-26-12):Flow-PMP
Attachment G.2
Client:Denison Mines Job No.: 1009740
Project:White Mesa Reclamation Plan Date:7/28/2012
Detail:Erosion Protection Computed By:TMS
Temple Method for Vegetated Slopes - Top Soil
Reference: Temple, D.M., Robinson, K.M., Ahring, R.M., and Davis, A.G., 1987. Stability Design of Grass-Lined Open Channels, USDA Handbook 667.
And as presented in UMTRA TAD Section 4.3.3 and NUREG 1623, Appendix A
Area Cell 2 at 0.5% Cell 3 top
PMP Design flow (cfs/ft)0.62 0.70
Concentration Factor, F 3 3
PMP Design flow (cfs/ft), q 1.86 2.10
Slope, S (ft/ft)0.005 0.005
average dry density (pcf)100 100 (assumed value)
average specific gravity 2.65 2.65 (assumed value)
void ratio, e 0.654 0.654
unit weight water (pcf)62.4 62.4
Topsoil Description Lean Clay Lean Clay
Plasticity Index, PI <10 <10 (from 2005 RP)
base allowable tractive shear stress (psf) ab= na na
void ratio correction factor, Ce= na na
allowable tractive shear stress (psf), a= 0.020 0.020
Long-term, PMP precip
Repr. stem length (ft) h(ave)
good veg 2 2 pg 36 and 39 of Temple et al. (1987)
poor veg 1 1
Repr. stem density (stems/sq ft), M(ave)
good veg 200 200 Temple Table 3.1, grass mixture
poor veg 67 67
Retardance curve index, Ci
good veg 7.62 7.62
poor veg 5.03 5.03
Cover factor, Cf
good veg 0.75 0.75 Temple Table 3.1, grass mixture
poor veg 0.375 0.375 assume min 30% coverage
allowable vegetated shear strength (psf), va
good veg 5.71 5.71
poor veg 3.78 3.78
Mannings n for soil roughness, ns=0.0156 0.0156
Mannings n for vegetal conditions, nr
good veg 0.0995 0.0924
poor veg 0.0531 0.0506
Mannings n for vegetated slopes, nv
good veg 0.0995 0.0924
poor veg 0.0531 0.0506
assumed depth of flow, d (ft)
good veg 1.402 1.446
poor veg 0.962 1.007
calculated q (cfs/ft), with veg
good veg 1.86 2.10
poor veg 1.86 2.10
qcalc - qdesign
good veg 0.00 0.00
poor veg 0.00 0.00
Iterate with d until q calc equals q design
velocity (ft/s), v
good veg 1.32 1.45
poor veg 1.93 2.09
effective shear stress (psf), e
good veg 0.0027 0.0032
poor veg 0.0162 0.0187
effective veg shear stress (psf) ve
good veg 0.4348 0.4480
poor veg 0.2839 0.2955
shear stress ratio, vegetated slope
good veg 13.1 12.8
poor veg 13.3 12.8
shear stress ratio, soil on vegetated slope
good veg 7.4 6.2
poor veg 1.2 1.1
Erosion Protection(7-26-12):Temple d75<.05
Attachment G.2
Client:Denison Mines Job No.: 1009740
Project:White Mesa Reclamation Plan Date: 7/28/2012
Detail:Erosion Protection Computed By: TMS
Temple Method for Vegetated Slopes - Top Soil Ammended with 25% Gravel
Reference: Temple, D.M., Robinson, K.M., Ahring, R.M., and Davis, A.G., 1987. Stability Design of Grass-Lined Open Channels, USDA Handbook 667.
And as presented in UMTRA TAD Section 4.3.3 and NUREG 1623, Appendix A
Area Cell 1 at 1% Cell 2 at 1% Cell 4A top
PMP Design flow (cfs/ft)0.63 0.55 0.86
Concentration Factor, F 3 3 3
PMP Design flow (cfs/ft), q 1.88 1.66 2.58
Slope, S (ft/ft)0.01 0.01 0.0082
average dry density (pcf)100 100 100 (assumed value)
average specific gravity 2.65 2.65 2.65 (assumed value)
void ratio, e 0.654 0.654 0.654
unit weight water (pcf)61.4 62.4 62.4
Topsoil Description
Topsoil with 25% 1"-minus
gravel
Topsoil with 25% 1"-
minus gravel
d75 (inches)0.2 0.2 0.2
from preliminary
gradation specs
base allowable tractive shear stress (psf) ab= na na na
void ratio correction factor, Ce= na na na
allowable tractive shear stress (psf), a= 0.080 0.080 0.080
Long-term, PMP precip
Repr. stem length (ft) h(ave)
good veg 2 2 2 pg 36 and 39 of Temple et al. (1987)
poor veg 1 1 1
Repr. stem density (stems/sq ft), M(ave)
good veg 200 200 200 Temple Table 3.1, grass mixture
poor veg 67 67 67
Retardance curve index, Ci
good veg 7.62 7.62 7.62
poor veg 5.03 5.03 5.03
Cover factor, Cf
good veg 0.75 0.75 0.75 Temple Table 3.1, grass mixture
poor veg 0.375 0.375 0.375 assume min 30% coverage
allowable vegetated shear strength (psf), va
good veg 5.71 5.71 5.71
poor veg 3.78 3.78 3.78
Mannings n for soil roughness, ns= 0.0196 0.0196 0.0196
Mannings n for vegetal conditions, nr
good veg 0.0987 0.1067 0.0824
poor veg 0.0528 0.0556 0.0469
Mannings n for vegetated slopes, nv
good veg 0.0994 0.1073 0.0833
poor veg 0.0541 0.0568 0.0484
assumed depth of flow, d (ft)
good veg 1.148 1.114 1.325
poor veg 0.797 0.760 0.956
calculated q (cfs/ft), with veg
good veg 1.88 1.66 2.58
poor veg 1.88 1.66 2.58
qcalc - qdesign
good veg 0.00 0.00 0.00
poor veg 0.00 0.00 0.00
Iterate with d until q calc equals q design
velocity (ft/s), v
good veg 1.64 1.49 1.95
poor veg 2.36 2.18 2.70
effective shear stress (psf), e
good veg 0.0068 0.0058 0.0094
poor veg 0.0400 0.0352 0.0501
effective veg shear stress (psf) ve
good veg 0.6979 0.6891 0.6687
poor veg 0.4493 0.4393 0.4392
shear stress ratio, vegetated slope
good veg 8.2 8.3 8.5
poor veg 8.4 8.6 8.6
shear stress ratio, soil on vegetated slope
good veg 11.7 13.8 8.5
poor veg 2.0 2.3 1.6
Erosion Protection(7-26-12):Temple with gravel added
Attachment G.2
Client:Denison Mines Job No.: 1009740
Project:White Mesa Reclamation Plan Date:7/28/2012
Detail:Erosion Protection Computed By:TMS
Abt and Johnson method (Abt and Johnson, 1991) applicable for slopes of 50% or less.
Angular-Shaped rock sizing equation:
For rounded rock, increase size by 40%.
Area
Cell 4A Flow Path 2
Southern Side Slope -
Angular
Non-Accumulating
Side Slopes -
Rounded
Cell 2 Northern Side
Slope - Angular
Side Slope (ft/ft) 0.2 0.2 0.2
angle (rad)0.197 0.197 0.197
PMP unit flow (cfs/ft) 0.86 0.06 0.64
Concentration Factor 3 3 3
Coef. Of Movement 1.35 1.35 1.35
design flow (cfs/ft) 3.49 0.25 2.61
Coef. Of Uniformity NA NA NA
design flow over rock (cfs/ft) 3.49 0.25 2.61
D50 (inches)5.27 1.70 4.48
Erosion Protection(7-26-12):CSU-Abt Riprap (for report)
Attachment G.2
Client:Denison Mines Job No.: 1009740
Project:White Mesa Reclamation Plan Date:7/28/2012
Detail:Erosion Protection Computed By:TMS
Preliminary Gradations
This spreadsheet calculates preliminary gradations of riprap based on D50
Source: NUREG 4620
Source: USDA, National Engineering Handbook, Part 633, Chapter 26, Gradation Design of Sand and Gravel Filters, October 1994.
Comment
Minimum D50 (in) 4.48
Assuming Angular Rock, Safety Factor Method for Top
Slope, Abt and Johnson (1991) method for side slopes
Rock thickness (in) 8.96
Based on constructability: 1.5 to 2*D50. May consider 12"
as minimum thickness for rock
Maximum D50 (in) 5.97 Based on constructability: Thickness/1.5
Maximum D50 (in) 22.40 Prevent gap-grading: minimum D50*5
Maximum D50 (in) 5.97 Smaller of two above criteria
Maximum D100 (in) 8.96 Based on constructability: 1*Thickness
Maximum D100 (in) 29.86 Based on internal stability?: 5*maximum D50
Maximum D100 (in) 8.96 Smaller of two above criteria
Minimum D100 (in) 6.72 1.5*minimum D50
Minimum D15 (in) 0.56 Based on internal stability: Maximum D100/16
Maximum D15 (in) 2.80 Prevent gap-grading: Minimum D15*5
Minimum D60 (in) 6.27 Prevent gap-grading: D60/D10<=6
Maximum D60 (in) 8.36 Prevent gap-grading: D60/D10<=6
Minimum D10 (in) 1.05 Prevent gap-grading: D60/D10<=6
Maximum D10 (in) 1.39 Prevent gap-grading: D60/D10<=6
Area
Description
Cell 4A
side slope
Erosion Protection(7-26-12):gradations
Attachment G.2
Client:Denison Mines Job No.: 1009740
Project:White Mesa Reclamation Plan Date:7/28/2012
Detail:Erosion Protection Computed By:TMS
Interstitial Velocities
Source: NUREG 1623, Section D
Abt, SR, JF Ruff, RJ Wittler (1991). Estimating Flow Through Riprap, Journal of Hydraulic Engineering, Vol. 117, No. 5, May.
Description
Non-
Accumulating
Side Slopes -
Rounded
Cell 1
Disposal
Area Side
Slope -
Angular
Cell 4A Flow
Path 2
Southern Side
Slope - Angular
Minimum D50 (inches) 1.70 4.48 5.27 from Safety Factor Method, or Abt/Johnson Method, assuming rounded rock
Minimum D10 (inches) 0.40 1.05 1.23 from preliminary gradation specs
Maximum D10 (inches) 0.53 1.39 1.64 from preliminary gradation specs
Slope (ft/ft) 0.2 0.20 0.20 from preliminary design
Min Velocity (ft/s) 0.37 0.60 0.65 calculated from Abt et al. (1991) based on Min D10
Max Velocity (ft/s) 0.43 0.69 0.75 calculated from Abt et al. (1991) based on Max D10
Underlying filter
required?No Recommended Recommended Per NUREG 1623, Appendix D, section 2.1.1
Erosion Protection(7-26-12):Interstitial Velocity Angular
Attachment G.2
Client:Denison Mines Job No.: 1009740
Project:White Mesa Reclamation Plan Date:7/9/2012
Detail:Erosion Protection Computed By:TMS
USDA Filter Gradation Calulations - 2010 Material Testing
Step 1: Plot Gradation Curve of Base Soil
Stockpile ID
Description
Sieve Sizes Diameter
(mm)% Finer Diameter
(mm)% Finer Diameter (mm) % Finer
Diameter
(mm)% Finer Diameter
(mm)% Finer Diameter
(mm)% Finer Diameter
(mm)% Finer Diameter
(mm)% Finer Diameter
(mm)% Finer
1 1/2" 38.1 100 38.1 100 38.1 100 38.1 100 38.1 100 38.1 100 38.1 100 38.1 100 38.1 100
1" 25.4 100 25.4 100 25.4 100 25.4 100 25.4 100 25.4 100 25.4 100 25.4 100 25.4 100
3/4" 19.1 100 19.1 100 19.1 100 19.1 100 19.1 100 19.1 100 19.1 100 19.1 100 19.1 100
3/8" 9.8 100 9.8 100 9.8 100 9.8 100 9.8 100 9.8 100 9.8 100 9.8 100 9.8 100
Nº 4 4.75 99.9 4.75 100 4.75 99.9 4.75 100 4.75 100 4.75 100 4.75 100 4.75 100 4.75 99.8
Nº 10 2 99.8 2 99.9 2 99.9 2 100 2 100 2 100 2 99.3 2 100 2 99.7
Nº 20 0.85 98.9 0.85 99.2 0.85 99.2 0.85 100 0.85 99 0.85 99.3 0.85 98.8 0.85 99.5 0.85 97.4
Nº 40 0.425 97.7 0.425 97.9 0.425 96.9 0.425 99.7 0.425 97.4 0.425 98.3 0.425 98.1 0.425 98.8 0.425 94.7
Nº 60 0.25 95.1 0.25 93.1 0.25 92.6 0.25 98.8 0.25 91.9 0.25 96.1 0.25 94.4 0.25 97.8 0.25 88.2
Nº 100 0.15 90.8 0.15 80.9 0.15 88.8 0.15 96.7 0.15 74.7 0.15 92.3 0.15 79.4 0.15 95.2 0.15 76.6
Nº 200 0.075 58.8 0.075 64.5 0.075 82.2 0.075 69.8 0.075 53 0.075 62.6 0.075 56.2 0.075 59.4 0.075 58.3
D15 estimated as 0.025
All Steps below are from USDA Ch. 26 Example 26-2A
Step 4. Base Soil
Category 2 2 2 2 2 2 2 2 2
D85 0.14 0.18 0.11 0.12 0.21 0.13 0.19 0.13 0.22
Step 5. Filtering
Criteria (Max D15)
(mm)0.70 0.70 0.70 0.70 0.70 0.70 0.70 0.70 0.70
Step 6. Min D15 0.08 0.07 0.05 0.06 0.08 0.07 0.08 0.08 0.08
Step 7. Ratio 9.15 10.03 12.79 10.86 8.24 9.74 8.74 9.24 9.07
Control Point 1
(D15max)0.38 0.35 0.27 0.32 0.42 0.36 0.40 0.38 0.39
Control Point 2
(D15min)0.08 0.07 0.05 0.06 0.08 0.07 0.08 0.08 0.08
Step 8. MaxD10 0.32 0.29 0.23 0.27 0.35 0.30 0.33 0.32 0.32
CP3 Max D60 1.91 1.74 1.37 1.61 2.12 1.80 2.00 1.89 1.93
CP4 Min D60 0.38 0.35 0.27 0.32 0.42 0.36 0.40 0.38 0.39
Step 9. CP5 D5min 0.08 0.08 0.08 0.08 0.08 0.08 0.08 0.08 0.08
CP6 D100 max 75.00 75.00 75.00 75.00 75.00 75.00 75.00 75.00 75.00
Step 10. CP7 D10 0.06 0.06 0.05 0.05 0.07 0.06 0.07 0.06 0.06
CP8 D90 20.00 20.00 20.00 20.00 20.00 20.00 20.00 20.00 20.00
For Plotting:4.75 100.00
Step 11. Connecting Control Points
CP D(mm) % Finer D(mm) % Finer D(mm) % Finer D(mm) % Finer D(mm) % Finer D(mm) % Finer D(mm) % Finer D(mm) % Finer D(mm) % Finer
4 0.382653 60 0.348837 60 0.273722628 60 0.32234957 60 0.424528 60 0.359425 60 0.400356 60 0.378787879 60 0.385935 60
2 0.076531 15 0.069767 15 0.054744526 15 0.064469914 15 0.084906 15 0.071885 15 0.080071 15 0.075757576 15 0.077187 15
5 0.075 5 0.075 5 0.075 5 0.075 5 0.075 5 0.075 5 0.075 5 0.075 5 0.075 5
6 75 100 75 100 75 100 75 100 75 100 75 100 75 100 75 100 75 100
3 1.913265 60 1.744186 60 1.368613139 60 1.611747851 60 2.122642 60 1.797125 60 2.001779 60 1.893939394 60 1.929674 60
1 0.382653 15 0.348837 15 0.273722628 15 0.32234957 15 0.424528 15 0.359425 15 0.400356 15 0.378787879 15 0.385935 15
7 0.063776 10 0.05814 10 0.045620438 10 0.053724928 10 0.070755 10 0.059904 10 0.066726 10 0.063131313 10 0.064322 10
Step 12. Determine Gradation from plot
Shaded boxes means these values were changed to meet the requirements from the references listed below.
References cited and listed in Appendix G
D50 base 0.06 0.06 0.05 0.05 0.07 0.06 0.07 0.06 0.06
D50 Fine Filter 0.31 0.29 0.23 0.27 0.35 0.30 0.33 0.31 0.32
D50 Course Filter 1.57 1.43 1.13 1.33 1.75 1.48 1.65 1.56 1.59
Nelson eqn 4.35 2.81 1.90 2.56 2.75 2.02 2.73 2.14 2.94 1.74
Cedergren eqn 5.3 24.67 24.67 24.67 24.67 24.67 24.67 24.67 24.67 24.67
Nelson eqn 4.36 2.81 1.90 2.56 2.75 2.02 2.73 2.14 2.94 1.74
W7 (Field ID 8) W1 (Field ID 12) W2 (Field ID 13)
Sandy Clay Random
Fill
E4 (Field ID 2)
Sandy Clay Random
Fill
E5 (Field ID 3) E6 (Field ID 4) E7 (Field ID 5) E8 (Field ID 6) W9 (Field ID 7)
W2 (Field ID 13)
Sandy Clay Random Fill Clay Random Fill Sandy Clay Random Fill
Sandy Clay Random
Fill
Sandy Clay Random
Fill
Sandy Clay Random
Fill Sandy Clay Random Fill
E6 (Field ID 4) E7 (Field ID 5) E8 (Field ID 6) W9 (Field ID 7) W7 (Field ID 8) W1 (Field ID 12)E4 (Field ID 2) E5 (Field ID 3)
Course Design
Fine Design
Band (Upper)
Filter Transtion Design_NRCS(7-6-12):2010Fine-Grained Material_Final
Attachment G.2
Client:Denison Mines Job No.: 1009740
Project:White Mesa Reclamation Plan Date:7/9/2012
Detail:Erosion Protection Computed By:TMS
USDA Filter Gradation Calulations - 2012 Material Testing
Step 1: Plot Gradation Curve of Base Soil
Field ID
Description
Sieve Sizes Diameter
(mm)% Finer Diameter
(mm)% Finer Diameter
(mm)% Finer Diameter
(mm)% Finer Diameter
(mm)% Finer Diameter
(mm)% Finer Diameter
(mm)% Finer Diameter
(mm)% Finer Diameter
(mm)% Finer Diameter
(mm)% Finer
2" 50.8 100 50.8 100 50.8 100 50.8 100 50.8 100 50.8 100 50.8 100 50.8 100 50.8 100 50.8 100
1" 25.4 100 25.4 100 25.4 81.93 25.4 93.18 25.4 100 25.4 100 25.4 82.21 25.4 85.17 25.4 75.41 25.4 100
3/4" 19.1 100 19.1 100 19.1 76.8 19.1 90.46 19.1 100 19.1 100 19.1 81.53 19.1 79.85 19.1 75.41 19.1 98.84
3/8" 9.8 100 9.8 99.31 9.8 66.01 9.8 79.02 9.8 100 9.8 99.64 9.8 75.03 9.8 71.12 9.8 69.81 9.8 97.64
Nº 4 4.75 99.56 4.75 98.46 4.75 60.03 4.75 69.56 4.75 99.89 4.75 99.08 4.75 70.97 4.75 65.34 4.75 68.41 4.75 94.13
Nº 10 2 97.56 2 97.21 2 56.18 2 59.53 2 99.72 2 97 2 66.88 2 59.49 2 66.04 2 89.65
Nº 20 0.85 95.84 0.85 96.11 0.85 54.66 0.85 53.25 0.85 99.46 0.85 95.03 0.85 64.04 0.85 55.59 0.85 63.76 0.85 86.42
Nº 40 0.425 94.66 0.425 95.19 0.425 52.56 0.425 49.39 0.425 98.73 0.425 93.04 0.425 59.3 0.425 48.97 0.425 58.56 0.425 84.16
Nº 60 0.25 92.35 0.25 93.34 0.25 47.28 0.25 43.49 0.25 96.47 0.25 88.27 0.25 45.76 0.25 33.93 0.25 47.26 0.25 80.58
Nº 100 0.15 86.48 0.15 89.93 0.15 39.4 0.15 34.43 0.15 94.12 0.15 83.32 0.15 38.09 0.15 20.12 0.15 39.94 0.15 75.53
Nº 200 0.075 76.74 0.075 82.68 0.075 28.78 0.075 25.11 0.075 61.5 0.075 50.38 0.075 26.77 0.075 13.78 0.075 28.17 0.075 50.1
Note: Areas with fiels ID's E1-A and W4-B were topsoil samples and thus were not included in this analysis
All Steps below are from USDA Ch. 26 Example 26-2A
Step 4. Base Soil
Category 2 2 3 3 2 2 3 4 3 2
D85 0.14 0.10 29.72 14.66 0.13 0.18 29.38 25.20 35.31 0.58
Step 5. Filtering
Criteria (Max D15)
(mm)0.70 0.70 53.73 35.21 0.70 0.70 62.53 100.79 67.20 0.70
Step 6. Min D15 0.10 0.10 0.16 0.18 0.10 0.10 0.17 0.27 0.16 0.10
Step 7. Ratio 7.00 7.00 343.64 196.48 7.00 7.00 371.98 368.62 420.65 7.00
Control Point 1
(D15max)0.50 0.49 0.78 0.90 0.50 0.50 0.84 1.37 0.80 0.50
Control Point 2
(D15min)0.10 0.10 0.16 0.18 0.10 0.10 0.17 0.27 0.16 0.10
Step 8. MaxD10 0.42 0.41 0.65 0.75 0.42 0.42 0.70 1.14 0.67 0.42
CP3 Max D60 2.50 2.45 3.91 4.48 2.50 2.50 4.20 6.84 3.99 2.50
CP4 Min D60 0.50 0.49 0.78 0.90 0.50 0.50 0.84 1.37 0.80 0.50
Step 9. CP5 D5min 0.08 0.08 0.08 0.08 0.08 0.08 0.08 0.08 0.08 0.08
CP6 D100 max 75.00 75.00 75.00 75.00 75.00 75.00 75.00 75.00 75.00 75.00
Step 10. CP7 min
D10 0.08 0.08 0.13 0.15 0.08 0.08 0.14 0.23 0.13 0.08
CP8 D90 20 20 20 20 20 20 20 20 20 20
For Plotting:4.75 100
Step 11. Connecting Control Points
CP D(mm)% Finer D(mm)% Finer D(mm)% Finer D(mm)% Finer D(mm)% Finer D(mm)% Finer D(mm)% Finer D(mm)% Finer D(mm)% Finer D(mm)% Finer
4 0.5 60 0.49 60 0.782 60 0.896 60 0.5 60 0.5 60 0.840 60 1.367 60 0.799 60 0.5 60
2 0.1 15 0.1 15 0.156 15 0.179 15 0.1 15 0.1 15 0.168 15 0.273 15 0.160 15 0.1 15
5 0.075 5 0.075 5 0.075 5 0.075 5 0.075 5 0.075 5 0.075 5 0.075 5 0.075 5 0.075 5
6 75 100 75 100 75 100 75 100 75 100 75 100 75 100 75 100 75 100 75 100
3 1.4 60 1.3 60 3.909 60 4.480 60 1.8 60 2.2 60 4.202 60 6.836 60 3.994 60 2.2 60
1 0.5 15 0.49 15 0.782 15 0.896 15 0.5 15 0.5 15 0.840 15 1.367 15 0.799 15 0.5 15
7 0.083 10 0.083 10 0.130 10 0.149 10 0.083 10 0.083 10 0.140 10 0.228 10 0.133 10 0.083 10
Step 12. Determine Gradation from plot
Shaded boxes means these values were changed to meet the requirements from the references listed below.
References cited and listed in Appendix G
D50 base 0.05 0.05 0.34 0.49 0.06 0.07 0.30 0.49 0.29 0.07
D50 Fine Filter 0.41 0.40 0.64 0.74 0.41 0.41 0.69 1.12 0.66 0.41
D50 Course Filter 1.20 1.12 3.21 3.68 1.51 1.82 3.46 5.62 3.28 1.82
Nelson eqn 4.35 3.61 4.95 0.03 0.06 3.88 2.72 0.03 0.05 0.02 0.86
Cedergren eqn 5.3 24.56 24.69 9.45 7.48 24.78 24.48 11.34 11.44 11.23 24.34
Nelson eqn 4.36 3.61 4.95 0.03 0.06 3.88 2.72 0.03 0.05 0.02 0.86
E3-A
W5-B W8-A
W8-B
Sandy Clay Random
Fill
Sandy Clay Random
Fill
Sandy Clay Random
Fill
W8-AW5-B W9-B
Sandy Clay Random
Fill
W8-B W9-BW2-B W5-AE3-A E5-B E8-B W2-A
E5-B
Sandy Clay Random
Fill
Sandy Clay Random
Fill Clay Random Fill
Sandy Clay Random
Fill
Sandy Clay Random
Fill
Sandy Clay Random
Fill
E8-B W2-A W2-B W5-A
Course Design
Band (Lower)
Fine Design
Band (Upper)
Filter Transtion Design_NRCS(7-6-12):2012 Fine-Grained Material
Attachment G.2
Client:Denison Mines Job No.: 1009740
Project:White Mesa Reclamation Plan Date:7/28/2012
Detail:Erosion Protection Computed By:TMS
Apron Protection
Source: Abt, SR, Johnson, TL, Thornton, CI, and Trabant, SC, Riprap Sizing
at Toe of Embankment Slopes, Journal of Hydraulic Engineering, Vol. 124, No. 7, July 1998.
Equation: D50=10.46*S^0.43*qd^0.56
Apron C:
Cell 2
Northern
Side Slope
Apron B:
Cell 4A
Southern
Side Slope
Apron A: Non-
Accumulating
Slopes West
unit discharge (cfs/ft) 0.64 0.86 0.06 0.06
Cr 1 1 1 1
Cf 3 3 3 3
Cm 1.35 1.35 1.35 1.35
design discharge (cfs/ft) 2.61 3.49 0.25 0.25
Slope (ft/ft) 0.2 0.2 0.2 0.2
D50 Angular (in) 9.0 10.5 2.4 2.4
D50 Rounded (in)12.5 14.8 3.4 3.4
Erosion Protection(7-26-12):Apron Protection
Attachment G.2
Client: Denison Mines Job No.: 1009740
Project: White Mesa Reclamation Plan Date: 7/28/2012
Detail: Erosion Protection Computed By: TMS
Interstitial Velocities - Apron
Source: NUREG 1623, Section D
Abt, SR, JF Ruff, RJ Wittler (1991). Estimating Flow Through Riprap, Journal of Hydraulic Engineering, Vol. 117, No. 5, May.
Description
Non-
Accumulating
Side Slopes -
Rounded
Cell 1 Disposal
Area Side
Slope - Angular
Cell 4A Flow
Path 2 Southern
Side Slope -
Angular
Minimum D50 (inches) 3.18 8.96 10.54 from Safety Factor Method, or Abt/Johnson Method, assuming rounded rock
Minimum D10 (inches) 0.74 2.09 2.46 from preliminary gradation specs
Maximum D10 (inches) 0.99 2.79 3.28 from preliminary gradation specs
Slope (ft/ft) 0.01 0.01 0.01 from preliminary design
Min Velocity (ft/s) 0.11 0.19 0.20 calculated from Abt et al. (1991) based on Min D10
Max Velocity (ft/s) 0.13 0.22 0.24 calculated from Abt et al. (1991) based on Max D10
Underlying filter
required?No No No Per NUREG 1623, Appendix D, section 2.1.1
Erosion Protection(7-26-12):Apron Interstitial Velocity
Attachment G.2
Client:Denison Mines Job No.: 1009740
Project:White Mesa Reclaimation Date:7/28/2012
Detail:Erosion Protection Computed By:TMS
Modified Universal Soil Loss Equation (MUSLE)
Source : Clyde et al. (1978) as presented in NUREG 4620, section 5.1.2
A=R*K*LS*VM
Topsoil Rock Mulch
Percent silt and very fine sand 43.6 32.7
Percent sand (0.10-2.0 mm)39.2 29.4
Percent organic matter 1.5 1.5
Soil structure Number 2 3
Permeability 3 2
Inputs for LS factor
Slope length (ft) 1400 1200
slope steepness (%) 0.5 0.82
m exponent 0.2 0.2 Table 5.2 of NUREG 4620
Topsoil Rock Mulch
R Rainfall Factor 30 30
K Soil Erodibility factor 0.28 0.12 From nomograph Fig. 5.1 of NUREG 4620
LS Topographic factor 0.16 0.19
VM Dimensionless erosion control factor 0.4 0.4 From Table 5.3 of NUREG 4620 for seedings, 0-60 days
A Soil Loss (tons/acre/year) 0.54 0.27
A Soil density (pcf)100 100
A Soil Loss (inches/1000 years)3.0 1.5
Inputs for K factor
From Table 5.1 of NUREG 4620 for eastern third of Utah
Erosion Protection(7-26-12):Soil Loss Equation
Attachment G.2
Client:Denison Job No.: 1009740
Project:White Mesa Mill Date:8/14/2012
Detail:Discharge Channel Computed By:JMC
Peak Discharge of PMP precipitation
Sed-Channel 148.40 1 26.3 16.4 2440.1
Q (cfs)Description
Total Drainage Area
(acres) C Tc (min) Intensity (in/hr)
riprap:Flow-PMP2
Attachment G.2
Client:Denison Job No.: 1009740
Project:White Mesa Mill Date:8/14/2012
Detail:Discharge Channel Computed By:JMC
Time of Concentration
1-hour PMP (in) 8.3
Kirpich SCS
Brant and
Oberman Average
Sed-Channel 0.010 4600 30.1 30.2 18.7 26.3 86.9 7.21 16.4
Source: Brant and Oberman(1975) as presented in UMTRA TAD (1989)
Formula: tc=C(L/Si^2)^(1/3).
Source:Kirpich (1940) as presented in NUREG 4620
Formula: tc=0.00013*L^0.77/S^0.385 with L in feet, tc in hours
Source: SCS as presented in NUREG 4620
Formula: tc=(11.9L^3/H)^0.385 with L in miles, H in feet, t in hours
% of one-hour PMP=RD/(0.0089*RD+0.0686) for tc<15 min based on Table 4.1 of TAD
Cell geometry and grading based on REC-1 Reclamation Plan Revisions, September, 2011
Intensity
(in/hr)
Time of Concentration (minutes)
Description
Slope
(feet/feet)
Path
Length
(feet)
% of 1-hour
PMP PDPMP (in)
riprap:Time of concentration
Attachment G.2
Client: Denison Mines Job No.: 1009740
Project: White Mesa Mill Date:8/2/2012
Detail:Discharge Channel Computed By:JMC
Peak Channel Velocity
Design flow:2,440 cfs
Trapezoid or triangular channels
slope (ft/ft)0.009 ft/ft
Channel Side Slope 1 (ft/ft) 0.33 ft/ft
Channel Side Slope 2 (ft/ft) 0.33 ft/ft
bottom width 150 ft
Q 2,440 cfs
n native soils 0.020 bedrock channel with minor irregularities
Area of flow (A) 258.52 ft^2
Wetted Perimeter Slope 1 (P1) 5.32 ft
Wetted Perimeter Slope 2 (P2) 5.32 ft
Hydraulic Radius (R) 1.61 ft
Top Width (T)160.1 ft
Maximum depth of flow (d) 1.67 ft
Q calc 2440.0 cfs ok
average velocity (v)9.4 fps 8-10 fps ok
unit discharge 15.74 cfs/ft take as total Q divided by average flow width
Copy of channel sizing:8 (3)
Attachment G.2
Client: Denison Mines Job No.: 1009740
Project: White Mesa Mill Date:8/14/2012
Detail:Discharge Channel Computed By:JMC
Peak Channel Velocity
Design flow:2,440 cfs
Trapezoid or triangular channels
slope (ft/ft)0.009 ft/ft
Channel Side Slope 1 (ft/ft) 0.33 ft/ft
Channel Side Slope 2 (ft/ft) 0.33 ft/ft
bottom width 150 ft
Q 2,440 cfs
n native soils 0.030 bedrock channel with moderate irregularities
Area of flow (A) 332.10 ft^2
Wetted Perimeter Slope 1 (P1) 6.77 ft
Wetted Perimeter Slope 2 (P2) 6.77 ft
Hydraulic Radius (R) 2.03 ft
Top Width (T)162.9 ft
Maximum depth of flow (d) 2.12 ft
Q calc 2440.0 cfs ok
average velocity (v) 7.3 fps less than 8-10 fps ok
unit discharge 15.60 cfs/ft take as total Q divided by average flow width
Copy of channel sizing:8 (6)
Attachment G.2
Client: Denison Mines Job No.: 1009740
Project: White Mesa Mill Date:8/2/2012
Detail:Discharge Channel Computed By:JMC
Manning's N-value Determination
From US Department of the Interior, Bureau of Reclamation. Design of Small Dams. p. 595. 1987.
Basic N-value for channels in Rock 0.015
Modifications of N-value 0.005 Minor degree of irregularity
0.010 Moderate degree of irregularity
0.020 Severe irregualrity
Based on seismic refraction data, test numbers 1-3, shear wave velocities ranged from 3100 to 7400 feet/sec (see test results from Nielsons, 1978, Appendix A D'Appolonia, 1979). The bedrock in the area of the proposed channel
excavation is anticpated to range from soft and rippable to hard rock requiring blasting. The excavated rock surface will likely exhibit minor ro moderate irregularity.
Assume an N-value ranging from 0.020 0.030
From US Army Corps of Engineers. Hydraulic Design of Flood Control Channels, EM 1110-2-1601. p.2-16. June 1994.
From Table 2-5, Suggested Maximum Permissible Mean Channel Velocities
Poor Rock (usually sedimentary) 10.0 fps
Soft Sandstone 8.0 fps
Soft Shale 3.5 fps
Good Rock (usually igneous or hard metamorphic) 20.0 fps
The bedrock within the channel excavation is anticipated to consist of fine to medium-grained sandstone of varying cementation and weathering, or claystone. (see borings by Dames and Moore, 1978)
Based on the presumed rock type and the referenced table above, permissible mean channel velocities may range up to 8 to 10 fps.
Copy of channel sizing:Sheet1
Attachment G.2

ATTACHMENT D

SUPPORTING DOCUMENTATION FOR INTERROGATORY 06/1:

REVISED APPENDIX E, SLOPE STABILITY ANALYSIS,
TO THE UPDATED TAILINGS COVER DESIGN REPORT
(APPENDIX D OF RECLAMATION PLAN, REVISION 5.0)

SLO
APP
OPE STA
PENDIX E

BILITY A
Update
E
ANALYSIS
ed Tailings Co
S
over Design RReport

Denison M

E.1 IN
This app
cells at th
located a
according
geotechn
analyses
Division o

Slope st
compute
of safety
Janbu’s
Lowe-Ka
(Morgens
performin
shear su

E.2 C
Slope st
condition
reclamat
with a 5H
conserva

A critical
the south
overall im
the slope
in Figure
The phre
analyses

A second
Cell 1 Di
The loca
Disposal
was ass
analyses

Slope sta
circular f
analyses
surfaces
surfaces

ines Corp.
NTRODUCT
pendix prese
he Denison
approximate
g to applic
nical stability
s presented
of Radiation
ability analy
r program S
y by any of t
Simplified, (
arafiath, and
stern and P
ng the com
rfaces and s
CRITICAL CO
tability anal
ns for post-re
ion were ev
H:1V slope,
ative shear s
cross sectio
heast corne
mpoundmen
e stability an
e E.1. The ta
eatic surface
s.
d cross sect
isposal Area
ation of cros
Area will in
umed to be
s.
ability analys
failure surfa
s were cond
through the
were analyz
TION
ents the meth
Mines (USA
ely 6.0 mile
cable stabil
y criteria in N
in MWH (2
Control (DR
yses were p
SLOPE/W (G
the following
(4) Spencer,
d (8) Gene
Price, 1965)
putations in
satisfies both
ONDITIONS
lyses are t
eclamation.
valuated and
(2) existing
strength para
on, cross se
r of the imp
t height as
nalyses pres
ailings are p
e was there
ion, cross se
a. This loca
ss section B
nclude mill d
e fully drain
ses were pe
aces for bot
ucted by ta
e clay liner s
zed in order
hods, input
A) Corp.’s (D
es south of
lity criteria
NRC (2003).
011) to inco
RC) interrog
performed u
GEO-SLOPE
g methods:
, (5) Morgen
eralized Lim
with a half-
SLOPE/W.
h moment an
S AND GEO
typically con
For the Whit
d included:
g inside surf
ameters bas
ection A, was
oundment.
well as base
ented in Tita
planned to b
efore estima
ection B, wa
ation was ch
B is shown
debris and c
ed and the
erformed by
th static and
rgeting both
system were
to calculate
E-1
and results
Denison) Wh
Blanding, U
under sta
These ana
orporate rev
gatories (DR
using limit e
E, 2007). Th
(1) Ordinar
nstern-Price
mit Equilibri
sine functio
. The meth
nd force equ
METRY
nducted for
te Mesa Mill
(1) reclaime
faces of the
sed on previo
s selected th
The cross
e topograph
an (1996). T
be dewatere
ated to be o
as selected t
hosen to add
in Figure E
contaminated
refore a ph
calculating
d pseudo-st
h shallow an
e evaluated f
e the factor o
Update
of slope sta
hite Mesa Ur
Utah. These
tic and se
alyses are an
visions to th
RC, 2012).
equilibrium m
he SLOPE/W
ry Fellenius
, (6) U.S. A
um. The
on for inter-s
hod uses bo
uilibrium.
r scenarios
l tailings cell
ed outside s
e embankme
ous reports.
hrough the s
section loca
hy and is sim
The location
ed prior to p
one foot abo
through the
dress DRC
.2. The m
d soils. The
hreatic surfa
factors of sa
tatic conditio
nd deep fail
for cross se
of safety for t
ed Tailings Co
ability analys
ranium Mill (
e analyses
eismic cond
n update to t
e analyses
methods wit
W program c
, (2) Bishop
Army Corps o
Morgenste
slice forces
oth circular
that repre
ls, critical co
surfaces of t
ents with a

southern dik
ation was se
milar to the
n of cross se
placement o
ove the line
northern em
interrogatori
material plac
e embankme
ace was not
afety along
ons. Circula
ure surfaces
ection B. A n
the critical fa
over Design R
MWH America
Augus
ses of the ta
(Mill). The M
were condu
ditions, inclu
the slope sta
to address
th the aid o
calculates fa
p’s Simplified
of Engineer
rn-Price me
was selecte
and non-cir
esent the c
onditions for
the embank
2H:1V slope
e of Cell 4A
elected base
location use
ection A is s
of the final c
er system fo
mbankment o
ies (DRC, 2
ced in the C
ent cross se
t included in
circular and
ar failure su
s. Block fa
number of fa
ailure.
Report
as, Inc.
st 2012
ailings
Mill is
ucted
uding
ability
Utah
of the
actors
d, (3)
s, (7)
ethod
ed for
rcular
critical
post-
kment
e; (3)
A near
ed on
ed for
hown
cover.
or the
of the
2012).
Cell 1
ection
n the
non-
urface
ailure
ailure

Denison M

E.3 M
Material
presente
historical
and Ass
testing c
and typic
summari

Erosion
embankm
values fo
material
Lambe (1
material
the 2012
based on
the estim
Effective
of 33 deg
percent
angle of

Cover S
geotechn
the rand
potential
each laye
contents
cover ma
2012 lab
internal f
and no c

Tailings
tests (Ch
long-term
dry dens
tailings w
analyses
with silt a
using the
density s
internal f
the Cell 4

Contami
include c
have sim
ines Corp.
MATERIAL P
strength pa
ed in Deniso
l laboratory
ociates, 198
conducted in
cal publishe
zed in Table
Protection
ment slopes
or sand and
strength pa
1969) for loo
mixed with
2 laboratory t
n 25% grave
mated dry d
strength pa
grees and n
(listed in th
internal frict
System: The
nical site inv
om fill laye
cover borro
er. The tota
for the cove
aterials were
boratory test
friction prese
ohesion.
Material: T
hen and As
m density of
ity. This is
was calculate
s. Based on
and some c
e Naval Des
silty sand. T
friction of 25
4B design st
inated Soils
contaminate
milar properti
PROPERTIE
arameters u
n (2009) for
testing on ta
87; D’Appol
n 2010 and
ed values.
e E.1.
: The erosi
, and rock m
gravel were
arameters w
ose to medi
25 percent g
testing resu
el by weight
ensity and t
arameters of
no cohesion
e specificat
ion presente
e cover syst
vestigation in
ers were es
ow materials
al unit weight
er layers use
e estimated
t results and
ented in Hol
The dry dens
ssociates, 19
the tailings
the same de
ed using the
existing ope
lay. The str
sign Manua
The strengt
5 degrees) a
tability analy
s/Mill Debr
d soils and
ies as the c
ES
sed for the
r the Cell 4B
ailings and c
onia, 1982;
2012 on po
The param
ion protectio
mulch on the
e used for t
were estimat
um dense s
gravel by we
lts for topso
t. The total
the long-ter
f the rock m
, based on
ions), and u
ed in Holtz (1
tem materia
n April 2012
timated usin
s (see Appe
ts for the cov
ed in the rad
based on t
d using the
tz (1981), re
sity of the ta
987 and We
is at 85 per
ensity used
e long-term w
erations at t
rength param
l for Soil M
h paramete
are consiste
yses.
ris: The m
mill debris.
cover soils.
E-2
slope stab
B slope stab
clay material
and Weste
otential cove
meters for ea
on materials
e top surfac
the riprap an
ted based o
sand and gra
eight. The d
il (see Appe
unit weight
m water co
ulch were e
a maximum
using the ge
1981).
al properties
. The total
ng 2010 an
endix A.2) a
ver layers w
don analyse
the maximum
generalized
esulting in a
ailings was e
estern Colo
rcent of the
for the rado
water conten
he site, the
meters of th
echanics DM
rs used for
ent with the
aterials to b
. The conta
The mater
Update
bility analysis
bility analyse
ls (Advance
ern Colorado
er borrow m
ach materia
include ripr
ce of the co
nd filter mat
on the lowe
avel. The ro
density of th
endix A.2) an
of the rock
ntent prese
estimated as
plasticity in
eneralized r
were estim
unit weight v
nd 2012 lab
and based o
were calculat
es. Effective
m measured
d relationsh
n angle of in
estimated as
orado Testin
average lab
on analyses.
nts assumed
tailings depo
e tailings we
M7-01 (NAV
the tailings
values pres
be placed i
aminated so
rial propertie
ed Tailings Co
s are based
es conducte
ed Terra Tes
o Testing, 1
aterials (see
al are discu
rap and filte
ver system.
terials. The
r bound typ
ock mulch c
he rock mulc
nd applying
mulch was
nted in the
s an angle o
ndex (PI) of
relationship
mated based
values used
boratory test
on the com
ted using the
e strength pa
d PI (30) fro
ip between
nternal frictio
s 90 pcf, bas
ng, 1999) an
boratory mea
. The total u
d for the tail
osits are pri
ere conserv
VFAC, 1986
(no cohesio
sented in De
n the Cell
oils will be f
es for the co
over Design R
MWH America
Augus
d on param
ed by Geosy
sting, 1996;
1999), labor
e Appendix
ussed below
er material o
Typical de
e riprap and
pical values
consists of to
ch was base
a rock corre
calculated
radon anal
of internal fr
the topsoil
between P
d on the upd
d in the mod
ts conducte
paction effo
e long-term w
arameters fo
om the 2010
PI and ang
on of 29 deg
sed on labor
nd assuming
asured maxi
unit weight o
ings in the r
marily fine s
vatively estim
6) as 0% re
on and an a
enison (2009
1 Disposal
from on-site
ontaminated
Report
as, Inc.
st 2012
meters
yntec,
Chen
ratory
A.2),
w and
n the
ensity
filter
from
opsoil
ed on
ection
using
yses.
riction
of 10
I and
dated
el for
ed on
ort for
water
or the
0 and
gle of
grees
ratory
g the
imum
of the
radon
sands
mated
lative
angle
9) for
Area
e and
soils

Denison M

and mill
85 perce

Clay Lin
based on
Testing,
compact
and a lon
on 15 ba
presente
average
percent p
internal f
and no c

Dike and
material
of Cell 4
based on
4A and 4

Bedrock
due to th
propertie

R
R
R
C
C
C
R
T
C
C
D
F
B

E.4 S
Stability
horizonta
ines Corp.
debris were
ent standard
ner: Cell 1
n laboratory
1996) and
ion. The to
ng-term wate
ar water cont
ed in Titan (
measured P
passing the
friction prese
ohesion.
d Foundatio
were estima
4B by Geosy
n laboratory
4B (Denison,
k: Failures a
he relatively
es for the bed
Riprap
Riprap Filter
Rock mulch
Cover Upper
Cover Middle
Cover Lower
Random Fill
ailings
Contaminated
Clay Liner
Dike
oundation
Bedrock
SEISMIC AN
analyses un
al accelerati
e conservativ
Proctor com
will be lined
y tests perfo
assuming t
tal unit weig
er content of
tents measu
(1996). Th
PI (60) of sam
No. 200 sie
ented in Hol
on: Density
ated as the
yntec (Denis
testing resu
, 2009).
are not antic
high streng
drock were m
Table E.
Materia
Layer (85%
e Layer (95%
Layer (80%
d Soils/Mill D
ALYSIS AN
nder seismic
on or seism
vely assume
mpaction).
d with a clay
ormed on Se
he clay will
ght for the c
f 14 percent
red for Sect
e strength
mples meeti
eve, and the
tz (1981), re
y and streng
values pres
son, 2009).
ults from sam
cipated to oc
gth of the un
modelled as
1. Material
al
SP compac
% SP compa
SP compac
Debris
ND SEISMIC
conditions w
mic coefficie
E-3
ed to be the
y liner. The
ection 16 cla
be compac
clay was cal
. The long-t
tion 16 clay s
parameters
ing the place
e generalize
esulting in a
gth paramet
ented in sta
The streng
mples obtain
ccur within th
nderlying sed
s those cons
Parameters

To
W
ction)
ction)
ction)
CITY
were conduc
nt is applied
Update
same as th
e dry densit
ay (D’Appol
cted to 95
lculated usin
term water c
samples by
for the clay
ement speci
ed relationsh
n angle of in
ters for the
ability analys
gth paramet
ned from the
he bedrock
dimentary ro
istent with s
s Used in M
otal Unit
Weight
(pcf)
125
125
110
107
120
100
100
95
107
110
137
137
130
cted as pse
d to both c
ed Tailings Co
he cover soi
ty of the cla
onia, 1982;
percent of s
ng the estim
content was
Chen and A
y were esti
fications for
hip between
nternal frictio
existing fou
ses performe
ters used in
e existing be
underlying t
ock. Theref
sedimentary
Model
Cohesion
(psf)
0
0
0
0
0
0
0
0
0
0
900
900
10000
udo-static a
ross-section
over Design R
MWH America
Augus
ls (compact
ay was estim
Advanced T
standard Pr
mated dry de
estimated b
Associates (1
mated using
r minimum P
n PI and ang
on of 24 deg
ndation and
ed for the de
the model
erm between
the embankm
fore, the ma
rock.
Internal
Friction
Angle°
36
30
33
29
29
29
29
25
29
24
26
26
45
nalyses, wh
ns. This se
Report
as, Inc.
st 2012
ted to
mated
Terra
roctor
ensity
based
1987)
g the
PI and
gle of
grees
d dike
esign
were
n Cell
ment,
aterial
ere a
eismic

Denison M

coefficien
coefficien
conducte
the Maxi
embankm
is provide

A liquefa
results i
materials
is analyz
horizonta
1979). T
the desig
at the sit
coefficien
design a
represen
reclaimed
analysis

E.5 D
The resu
values re
surfaces
Cr
Cross
Cell 4
Cross
Cell 1

As show
recomme
model p
condition

ines Corp.
nt represent
nt of 0.1 g w
ed for the sit
mum Credib
ment. A sum
ed as Attach
action analys
ndicate the
s that do not
zed by a p
al acceleratio
The seismic
gn earthquak
te (typically
nt as a frac
and docume
nts the pos
d conditions
is 0.10g (eq
DISCUSSION
ults of stabili
epresent th
for a Morge
ross-Sectio
s Section A -
A Embankm
s Section B –
Embankme
wn in Table
ended value
profile figure
ns are shown
s the horizo
was used for
te (MWH, 20
ble Earthqua
mmary of the
hment E.1 to
sis was con
e tailings ar
t liquefy or l
pseudo-stati
on or seismi
coefficient r
ke, and is re
at the base
ction of the
ented in DO
t-reclamatio
s to be 0.15
ual to 2/3 of
N OF STABI
ity analyses
e lowest ca
enstern-Price
Table E
n
Fai
Ty
-
ment
Sha
Circ
De
Circ
–
ent
Sha
Circ
De
Circ
Bl
E.2, all ca
es of 1.5 fo
es and SLO
n in Figures
ntal accelera
the analyse
012). This s
ake (MCE)
e site seism
o this append
nducted for
re not susc
ose shear s
c approach
c coefficient
represents a
epresented a
e of the stru
PGA has b
OE (1989).
n condition
5g. The sei
f the PGA).
ILITY ANAL
for Cross-s
alculated fac
e Analysis.
E.2. Slope S
ilure
ype
allow
cular Ps
eep
cular Ps
allow
cular Ps
eep
cular Ps
ock Ps
alculated fac
r static con
OPE/W out
E.3 through
E-4
ations applie
es based on
seismic coeff
calculated t
icity is provi
dix, for ease
the tailings
ceptible to
strength with
h. This co
t to the struc
an inertial for
as a fraction
ucture). Th
been adopte
A seismic
s. MWH
smic coeffic

LYSIS RESU
section A an
ctor of safe

Stability An
Loading
Condition
Static
seudo-Static
Static
seudo-Static
Static
seudo-Static
Static
seudo-Static
Static
seudo-Static
ctors of saf
nditions and
tput figures
E.14.
Update
ed on the st
the most rec
ficient repre
to occur dur
ided in the M
e of reference
and is pres
earthquake
h seismic sh
onsists of a
cture being a
rce due to s
n of the pea
he strategy
ed in review
coefficient o
(2012) esti
cient used fo
ULTS
nd B are pre
ety from a
nalysis Resu
Requ
Facto
Safe
1.5
c 1.
1.5
c 1.
1.5
c 1.
1.5
c 1.
1.5
c 1.
fety were s
1.1 for pse
s for static
ed Tailings Co
ructure by a
cent seismic
sents the se
ring the long
MWH (2012
e.
sented in A
e-induced liq
aking, seism
application o
analyzed (de
strong groun
k ground ac
of represen
w of uranium
of 2/3 of th
imated the
or the pseu
esented in T
number of
ults
uired
ors of
ety
C
5
1
5
1
5
1
5
1
5
1
significantly
eudo-static
and pseud
over Design R
MWH America
Augus
an earthquak
c hazard ana
eismic loadin
g-term life o
). This docu
Appendix F.
quefaction.
mic slope sta
of an equiv
escribed in S
d motions d
cceleration (P
nting the se
m tailings fa
he PGA typ
mean PGA
do-static sta
able E.2. T
individual fa
Calculated
Factors of
Safety
3.20
2.03
3.83
2.56
3.10
1.96
3.24
2.07
3.41
2.14
above the
conditions.
do-static loa
Report
as, Inc.
st 2012
ke. A
alysis
ng for
of the
ument
The
For
ability
valent
Seed,
during
PGA)
eismic
acility
pically
A for
ability
These
ailure
NRC
The
ading

Denison M

E.6 R
Advance

Campbel
M
E

Chen an
R

D’Appolo
D
N

Denison
R
R
C

GEO-SLO

Holtz, R.
P

Lambe, T
Morgens
G
MWH Am
M

MWH Am
M
M

Naval Fa
Nuclear
R
R

U.S. Dep
D
N

U.S. Geo
S
co

ines Corp.
REFERENCE
d Terra Tes
ll, K.W. and
Mean Horizon
Earthquake E
nd Associate
Report prepa
onia Consult
Data, White
Nuclear, Inc.
Mines (US
Response to
Round 1 inte
Calculation P
OPE Interna
.D. and Kov
Prentice-Hall
T.W. and Wh
tern, N.R., a
Geotechnique
mericas, Inc
Mines (USA)
mericas, Inc
Mesa Uraniu
Mines (USA)
acilities Engi
Regulatory
Reclamation
Radiation Co
partment of E
DOE/AL 050
New Mexico.
ological Surv
Seismic Haza
onterminous
ES
ting (1996).
d Bozorgnia
ntal Compon
Engineering
es, Inc., 19
ared for Ener
ting Enginee
Mesa Urani
on 8 March
A) Corporat
Division of
errogatory, C
Package. Ja
ational Ltd, 2
vacs, W.D.,
, 1981.
hitman, R.V.
and V.E. Pric
e, Vol. 15, p
c. (MWH), 2
Corp. Sept
. (MWH), 20
m Facility, B
Corp. May 3
neering Com
Commission
Plan for the
ntrol Act.” N
Energy (DO
0425.0002, U
vey (USGS),
ard Maps Pr
s12008/. Ma
Physical so
a, Y., 2007.
nent of Peak
Research C
987. Physica
rgy Fuels Nu
ers, Inc. (19
um Project,
1982.
tion (Deniso
Radiation C
Cell 4B Des
nuary 9.
2007. Slope/
1981. An In
., 1969. Soil
ce, 1965. Th
p. 79-93.
2011. Upda
tember.
012. Site-Sp
Blanding, Ut
30.
mmand (NAV
n (NRC), 20
e Mill Tailing
NUREG-162
E), 1989. T
Uranium Mi
, 2008. Eart
rogram (NSH
ay.
E-5
oil data, Whi
NGA Groun
k and Spectr
Center Repor
al Soil Data
uclear, Inc.
982), Letter
Blanding, U
on), 2009.
Control (“DR
sign, Exhibit
/W, Version
ntroduction t
Mechanics.
he Analysis
ated Tailings
pecific Proba
tah. Techni
VFAC), 1986
003. “Stan
gs Sites Un
0. Division o
Technical Ap
ill Tailings R
thquake Haz
HMP). http://
Update
te Mesa Pro
nd Motion R
ra Ground M
rt. 2007/02
a, White Me
Report, Se
Utah, Repor
Cell 4B Lin
RC”) Reques
t A, Geosyn
7.17, Calga
to Geotechn
. New York:
of the Stabi
s Cover Des
abilistic Seis
ical memora
6. Soil Mech
dard Review
nder Title II
of Waste Ma
pproach Doc
Remedial A
zards Progra
/earthquake.
ed Tailings Co
oject, Blandi
Relations fo
Motion Param
, 246 p.
esa Project,
ection 16 Cl
rt prepared f
ning System
st of Addition
ntec Slope S
ry, Alberta.
nical Enginee
John Wiley
lity of Gener
sign. Prepa
smic Hazard
andum prepa
hanics Desi
w Plan for
of the Uran
anagement,
cument, Rev
Action Proje
am: United S
.usgs.gov/ha
over Design R
MWH America
Augus
ng Utah, Jul
or the Geom
meters. In P
, Blanding
ay Material
for Energy F
m Design Re
nal Informat
Stability Ana
ering. New
& Sons, 196
ral Slip Surfa
ared for De
d Analysis, W
ared for De
ign Manual 7
the Review
nium Mill Ta
June.
vision II, UM
ct, Albuque
Stated Natio
azards/produ
Report
as, Inc.
st 2012
ly 25.
metric
Pacific
Utah,
Test
Fuels
eport,
tion –
alysis
York:
69.
aces.
nison
White
nison
7.01.
of a
ailings
TRA-
erque,
nal
ucts/

Denison M

Utah De
D
R

Western
C
ines Corp.
partment of
Denison Mine
Round 1. Ma
Colorado Te
Cell 2 and Ce
Environme
es (USA) Co
arch.
esting, Inc.,
ell 3, Prepare
ntal Quality,
orp’s White
1999. Repo
ed for Intern
E-6
, Utah Divis
Mesa Recla
ort of Soil Sa
national Uran
Update
sion of Radi
amation Plan
ample Testi
nium (USA)
ed Tailings Co
ation Contro
n, Rev. 5.0,
ng of Tailing
Corporation
over Design R
MWH America
Augus
ol (DRC). 2
Interrogato
gs Collected
. May 4.
Report
as, Inc.
st 2012
2012.
ries -
from
L;\D.,i~n-Drott"'~\Cli.nh-A-H\DE:~SON MKS\013-Sh••\50\\201i-08-26 COVR DS~REP\1009740 SLCPE
200 FT
FIGURE E.1
1009740SLOPE
o
e MWH
DATE
AUG 2012
FLE NAME
SCALE
LEGEND:
-5605 -GROUND SURFACE CONTOURAND ELEVATION FROM 2007L1DARSURVEY,FEET
FINAL COVER SURFACE-5605 -ELEVATION (TOP OF EROSIONPROTECTION LAYER). FEET
200
ooo
cii
NN
w
SLOPE STABILITY
CROSS SECTION A LOCATION
WHITEMESAMILL TAILINGSRECLAMATION
5612 ~
~=-------+
TITLE
PROJECT
CELL4A
OENISOJ)J J
MINES
Denison Mines (USA)Corp
\
N 10,161,000
J
CELL 1
KEY MAP
NOT TO SCALE
1 ~
1
AREASHOWNLAT RIGHT
CELL4B
1-
)
N 10 ,162 000 -
PROJECT
Cross Section A on Cell 4A Slope Stability
Analysis Model Profile
TITLE
DATE
FILENAME
FIGURE E.3
White Mesa Mill Reclamation
AUG 2012
AppendixE Slope StabilityResults.pptxDenison Mines (USA) Corp
PROJECT
Cross Section A on Cell 4A Slope Stability
Analysis Static Conditions - Deep Circular
TITLE
DATE
FILENAME
FIGURE E.4
White Mesa Mill Reclamation
AUG 2012
AppendixE Slope StabilityResults.pptxDenison Mines (USA) Corp
PROJECT
Cross Section A on Cell 4A Slope Stability Analysis
Pseudo-Static Conditions - Deep Circular
TITLE
DATE
FILENAME
FIGURE E.5
White Mesa Mill Reclamation
AUG 2012
AppendixE Slope StabilityResults.pptx
Denison Mines (USA) Corp
PROJECT
Cross Section A on Cell 4A Slope Stability
Analysis Static Conditions - Shallow
TITLE
DATE
FILENAME
FIGURE E.6
White Mesa Mill Reclamation
AUG 2012
AppendixE Slope StabilityResults.pptx
Denison Mines (USA) Corp
PROJECT
Cross Section A on Cell 4A Slope Stability
Analysis Pseudo-Static Conditions - Shallow
TITLE
DATE
FILENAME
FIGURE E.7
White Mesa Mill Reclamation
AUG 2012
AppendixE Slope StabilityResults.pptx
Denison Mines (USA) Corp
PROJECT
Cross Section B on Cell 1 Slope Stability Analysis
Model Profile
TITLE
DATE
FILENAME
FIGURE E.8
CAÑON CITY MILLING FACILITY
AUG 2012
Appendix E Slope Stability Results.pptxDenison Mines (USA) Corp
PROJECT
Cross Section B on Cell 1 Slope Stability Analysis
Static Conditions - Deep Circular
TITLE
DATE
FILENAME
FIGURE E.9
CAÑON CITY MILLING FACILITY
AUG 2012
Appendix E Slope Stability Results.pptxDenison Mines (USA) Corp
PROJECT
Cross Section B on Cell 1 Slope Stability Analysis
Pseudo-Static Conditions - Deep Circular
TITLE
DATE
FILENAME
FIGURE E.10
CAÑON CITY MILLING FACILITY
AUG 2012
Appendix E Slope Stability Results.pptxDenison Mines (USA) Corp
PROJECT
Cross Section B on Cell 1 Slope Stability Analysis
Pseudo-Static Conditions - Shallow Circular
TITLE
DATE
FILENAME
FIGURE E.11
CAÑON CITY MILLING FACILITY
AUG 2012
Appendix E Slope Stability Results.pptxDenison Mines (USA) Corp
PROJECT
Cross Section B on Cell 1 Slope Stability Analysis
Pseudo-Static Conditions - Shallow Circular
TITLE
DATE
FILENAME
FIGURE E.12
CAÑON CITY MILLING FACILITY
AUG 2012
Appendix E Slope Stability Results.pptxDenison Mines (USA) Corp
PROJECT
Cross Section B on Cell 1 Slope Stability Analysis
Static Conditions - Block
TITLE
DATE
FILENAME
FIGURE E.13
CAÑON CITY MILLING FACILITY
AUG 2012
Appendix E Slope Stability Results.pptxDenison Mines (USA) Corp
PROJECT
Cross Section B on Cell 1 Slope Stability Analysis
Pseudo-Static Conditions - Block
TITLE
DATE
FILENAME
FIGURE E.14
CAÑON CITY MILLING FACILITY
AUG 2012
Appendix E Slope Stability Results.pptxDenison Mines (USA) Corp

ATTA
MW
ACHMENT E
WH (2012)
Update
E.1
ed Tailings Coover Design RReport

TECHNICAL MEMORANDUM

TO: Mr. Harold Roberts DATE: May 30, 2012
Denison Mines (USA) Corp.

FROM: Eileen M. Dornfest, P.G. REFERENCE: 1009740

REVIEWED BY: Thomas E. Kelley, P.E.

SUBJECT: Site-Specific Probabilistic Seismic Hazard Analysis
White Mesa Uranium Facility
Blanding, Utah

1.0 INTRODUCTION

The purpose of this memorandum is to report the results of a site-specific probabilistic seismic hazard
analysis conducted to develop seismic design criteria for the Denison Mines (USA) Corp. (Denison)
White Mesa uranium mill (Site). This memorandum has been prepared in response to Interrogatory
05/1: Seismic Hazard Evaluation for the Utah Division of Radiation Control (DRC) Interrogatories on
the White Mesa Reclamation Plan, Rev. 5.0 (DRC, 2012) for the Denison Site, wherein it was
requested that an updated site-specific probabilistic seismic analysis be performed and reported in lieu
of using USGS National Hazard Maps for developing seismic design parameters. Previous seismic
hazard analyses were conducted for the design of the Cell 4A and 4B facilities (MFG, Inc. 2006; Tetra
Tech, Inc. (Tetra Tech), 2010), and are attached to this memorandum as Attachments 1 and 2,
respectively. The regional physiographic and tectonic setting of the site, as well as regional seismicity
have been discussed in previous reports (Umetco, 1998; MFG, Inc. 2006; Tetra Tech, 2010; Denison,
2011). This information is not reiterated herein.

The Site is located approximately 6 miles south of Blanding Utah, at approximately 37.5° N latitude and
109.5° W longitude.

2.0 DESIGN CRITERIA

Different seismic criteria have been established for short-term operational and long-term reclaimed
conditions of the tailings cells at the Site. The projected operational lifetime of the most recently
constructed tailings cell at the Site is estimated to be approximately 50 years, from the time of
construction through the time when the cell will have been dewatered and reclaimed. The design life
for the reclaimed facility is required to be 1,000 years to the extent reasonably achievable, and at least
200 years, per the US Environmental Protection Agency (EPA) (EPA 40 CFR 192) and the US Nuclear
Regulatory Commission (NRC) (NRC 10 CFR Appendix A to Part 100 A). Previous seismic hazard
analyses for the Site evaluated PGAs for operational conditions (MFG, 2006) and long-term reclaimed
conditions (Tetra Tech, 2010).

Harold Roberts, Denison Mines Corporation
May 30, 2012
Page 2 of 5

The seismic design criteria for operational conditions were evaluated previously by MFG (2006) using
both deterministic and probabilistic approaches. In their probabilistic analysis, MFG selected a PGA
with an average return period of 2,475 years as the probabilistic design earthquake. MFG used United
States Geological Survey (USGS) National Seismic Hazard Maps available at the time to estimate the
seismic event with a return period of 2,475 years. The use of a 2,475-year return period in formulating
the probabilistic operational design criteria is considered conservative as this event has a 2-percent
probability of exceedance over the anticipated 50-year operational design life.

Tetra Tech (2010) subsequently evaluated the seismic design criteria for reclaimed tailings cells. As
discussed above the reclaimed tailings cells are assumed have a design life of 200 to 1,000 years.
Tetra Tech also used both deterministic and probabilistic approaches in evaluating the seismic design
criteria. Tetra Tech selected an average return period of 9,900 years as appropriate for determining the
probabilistic seismic design criteria. The PGA with a 9,900 year return period was estimated for the
Site based on data from the USGS 2008 National Seismic Hazard Mapping Program (NSHMP) PSHA
Interactive Deaggregation website. The use of a 9,900-year return period in formulating the
probabilistic design criteria for reclaimed conditions is considered conservative as this event has a 2
percent probability of exceedance during a 200-year period and a less than 10 percent probability of
exceedance in a 1,000-year period.

The updated site-specific probabilistic seismic hazard analyses described in this memorandum
incorporates the conservative return periods assumed by MFG (2006) and Tetra Tech (2010) for
operational and long-term design, respectively, in order to maintain consistency with previous
probabilistic seismic hazard analyses for the Site.

3.0 REGIONAL SEISMICITY

A review of historic earthquakes that have occurred within 200 miles (322 km) of the Site was
performed to update information provided by Tetra Tech (2010). Several earthquake databases were
evaluated to develop an earthquake record for an area with a 200 mile radius of the Site, including
earthquakes from 1700 to May 14, 2012. This record provides a general overview of the seismicity
near the Site.
Catalogs from the USGS National Seismic Hazard Mapping Program (NSHMP) for the Western United
States (WUS) and Central and Eastern United States (CEUS) (Petersen et al., 2008) were reviewed to
compile information on the historic earthquakes. Since attenuation relations, completeness, and
magnitude-conversion rules all vary regionally, Petersen et al. (2008) built two catalogs: a moment-
magnitude (Mw) catalog for WUS and a body-wave-magnitude (Mb) catalog for the CEUS. The final
database includes historical seismic events from 1700 through 2006. Events are limited to those with a
magnitude greater than or equal to 4.0. This database contains 86 events that occurred within 200
miles (322 kilometers) of the Site.
Historical earthquake information from the WUS and CEUS catalogs was supplemented by an
additional search of the National Earthquake Information Center (NEIC) database, also maintained by
the USGS. This search was conducted for the time period of January 1, 2007 through May 14, 2012
and resulted in 2 additional earthquakes. NEIC earthquakes were limited to those with a magnitude of
4.0 or greater within 200 miles of the site, in order to be consistent with the WUS and CEUS catalogs.

Figure 1 shows the locations and magnitudes of the earthquakes with magnitudes of 4.0 or greater that
were identified within a 200 mile radius of the Site. The earthquakes generally had small magnitudes,
Harold Roberts, Denison Mines Corporation
May 30, 2012
Page 3 of 5

and more than 70 percent of the events had a magnitude less than 5.0. Only 2 percent of the events
had a magnitude greater than 6.0. Figure 1 shows that earthquake activity within a 200-mile (322 km)
radius of the site is diffuse, with the exception of the western edge of the study area, which lies within
the Intermountain Seismic Belt. A tabulated list of historic earthquakes greater than magnitude 4.0
within a 200 mile radius of the Site is included in Attachment 3.

In order to supplement the evaluation of earthquakes with a Mw or Mb greater than 4.0, an evaluation
of low magnitude events (greater than or equal to 2.4) was also conducted using the NEIC database for
locations within 80 miles (129 km) of the site. These events are shown in Figure 2 and are tabulated in
Attachment 3.

The largest historical earthquake event within 200 miles of the Site is estimated to have had a
magnitude of 6.5. This event occurred approximately 164 miles southeast of the site, near the town of
Richfield, Utah on November 11, 1901. The event closest to the Site had a magnitude of 4.0 and
occurred on August 22, 1986, approximately 59 miles west of the Site.

4.0 SITE-SPECIFIC PROBABILISTIC SEISMIC HAZARD

The site-specific seismic hazard was evaluated probabilistically by using the USGS 2008 NSHMP
PSHA Interactive Deaggregation website (https://geohazards.usgs.gov/deaggint/2008/). As part of its
2008 National Seismic Hazard Mapping project, the USGS performed a probabilistic seismic hazard
analysis of the entire United States, using information compiled by Petersen et al. (2008). The web-
based PSHA program provides estimates of the deaggregated seismic hazard at specific spectral
periods for the conterminous United States. The spectral period equal to 0.0 seconds is the PGA. The
program incorporates regional seismicity data including background earthquakes (unassociated with
faults), earthquakes associated with faults, fault characteristics, and regionally-appropriate attenuation
relationships.

The average shear wave velocity for the top 30 meters below the ground surface at the site (Vs30) is
an input variable to the PSHA program. MWH checked Tetra Tech’s calculation of Vs30 for the
uppermost 100 feet of soils and bedrock underlying the site. The drilling logs by Tetra Tech (2010) and
Dames and Moore (1978) were used to obtain information about the subsurface conditions at the site
(Standard Penetration Test (SPT) blow counts, bedrock descriptions, and depths of auger refusal) and
to calculate values of Vs for the soils and estimate values of Vs for the bedrock materials within 100
feet of the ground surface. The average value of SPT blow counts for the silty sand and soil material
encountered in the top 30 feet of the Tetra Tech boring is 59 (Tetra Tech, 2010). Using information in
Sykora (1987) (eqs.20, 21 and Table 4 eq. 8) values of Vs30 were calculated to range from
approximately 660 feet/second (ft/s) to 990 ft/s (approximately 200 to 300 meters/second (m/s)). This
is also consistent with information presented in Fig. 5, Fig. 6, Fig. 10, and Table 8 of Sykora (1987).
Based on the bedrock descriptions presented in the drilling logs by Dames and Moore (1978) to a
maximum depth of 140 feet, the estimated seismic velocity for the remaining 70 feet of generally well-
cemented sandstone with minor interbedded claystone, siltstone and conglomerate, is estimated to
range from 800 to 1,000 m/s. A weighted average of seismic velocity for the upper 100 feet below the
Site was calculated to range from approximately 620 m/s to 700 m/s. This seismic velocity correlates
with materials characterized as Site Class D – Stiff Soil/Soft Rock by both the IBC and NEHRP.

The NSHMP 2008 PSHA Interactive Deaggregation web site limits input values of Vs30 to either 760
m/s or 2,000 m/s. These seismic velocities correspond to Site Class BC (intermediate between dense
Harold Roberts, Denison Mines Corporation
May 30, 2012
Page 4 of 5

soil and rock) and Site Class A (hard rock), respectively. The input value for Vs30 chosen for the Site
was 760 m/s.

The Interactive Deaggregation program was used to calculate the site-specific PGA for operational and
reclaimed conditions at the Site. As stated previously, the PGA associated with a 2,475 year return
period was chosen to represent the operational conditions at the facility and the PGA associated with a
9,900 year return period was chosen to represent the reclaimed facility conditions. The PGA calculated
for the operational lifetime of the facility is 0.07g as shown on Figure 3. The PGA calculated for the
long-term conditions is 0.15g as shown on Figure 4.

The USGS PSHA program provides the deaggregation of ground-motion hazard for specific probability
levels or return periods. The deaggregation provides the percentage contributions to the site-specific
seismic hazard for the range of magnitudes and distances used in the PSHA. The USGS plots of the
deaggregated hazard at the Site for the 2,475 and 9,900 year return periods are shown on Figures 3
and 4 respectively. Figure 3 indicates that earthquakes contributing to the aggregate probabilistic
hazard at the 2,475-year-return-period level had a mean distance of 87.3 km (53 miles) from the Site
and a mean magnitude of 5.8. Earthquakes contributing to the probabilistic hazard at the 9,900-year-
return period level had a mean distance of 51.5 km (31.3 miles) from the Site and a mean magnitude of
5.8, as shown on Figure 4. As a result, it is recommended that a magnitude 6 earthquake be used, in
conjunction with the PGAs described above, in seismic analyses at the Site.

Figures 5 and 6 show the response spectra for the design events for the operational and long-term
conditions, respectively. This information was obtained from the USGS PSHA program. Attachment 4
contains text output of the deaggregated seismic hazard from the PSHA program.

5.0 CONCLUSIONS

Results of the PSHA conclude the mean PGA for operational conditions is estimated to be 0.07g. This
PGA is associated with an average return period of 2,475 years and has a 2 percent chance of
exceedance in the anticipated 50 year operational design life of the cells. The mean PGA for reclaimed
conditions is estimated to be 0.15g. This PGA is associated with an average return period of 9,900
years, which for a design life of 200 to 100 years, has a probability of exceedance of 2 percent to 10
percent, respectively. The probabilistic hazard at the Site is associated with a mean earthquake
magnitude of 6.

REFERENCES

Dames and Moore, 1978. Site Selection and Design Study - Tailing Retention and Mill Facilities, White
Mesa Uranium Project. January 17.

Denison Mines (USA) Corp. 2011. Reclamation Plan, White Mesa Mill, Blanding, Utah. Revision 5.
September.

MFG, Inc. 2006. White Mesa Uranium Facility, Cell 4 Seismic Study, Blanding, Utah. November 27.

Petersen, M.D., Frankel, A.D., Harmsen, S.C., Mueller, C.S., Haller, K.M., Wheeler, R.L., Wesson, R.L.,
Zeng, Y., Boyd, O.S., Perkins, D.M., Luco, N., Field, E.H., Wills, C.J., and Rukstales, K.S.
Harold Roberts, Denison Mines Corporation
May 30, 2012
Page 5 of 5

2008. Documentation for the 2008 Update of the united States National Seismic Hazard Maps.
U.S. Geological Survey Open-File Report 2008-1128.

Sykora, D.W. 1987. Examination of Existing Shear Wave Velocity and Shear Modulus Correlations in
Soils. U.S. Army Corps of Engineers Miscellaneous Paper GL-87-22. September.

Tetra Tech, Inc. 2010. Technical Memorandum: White Mesa Uranium Facility, Seismic Study Update
for a Proposed Cell, Blanding Utah. February 3.

UMETCO. 1988. Cell 4 Design, Appendix A, White Mesa Project

Utah Department of Environmental Quality, Utah Division of Radiation Control (DRC). 2012. Denison
Mines (USA) Corp’s White Mesa Reclamation Plan, Rev. 5.0, Interrogatories - Round 1. March

Attachments:
Figures

Attachment 1: White Mesa Uranium Facility, Cell 4 Seismic Study, Blanding Utah (MFG, Inc. 2006)

Attachment 2: Technical Memorandum re: White Mesa Uranium Facility, Seismic Study Update for a
Proposed Cell, Blanding Utah (Tetra Tech, Inc. 2008)

Attachment 3: Tabulated Lists of Historical Earthquakes Near the White Mesa Mill.

Attachment 4: US Geological Survey PSHA Deaggregation Data

FIGURES

~SALT LAKE CITY~"---LEGEND
--------.>:----------®--INTERSTATE
.107
-------<,-§-u.s.HIGHWAY
~U T A -:<,
<,DENVER STATE BORDER
«43
-,EARTHQUAKES
22
25 .14 ~•MAGNITUDE 4.0-4.9
.20 .49 3 •
0
MAGNITUDE 5.0-5.9
92 30 \•MAGNITUDE 6.0-1;.9
108 6 C a L ~R A a 200 EARTHQUAKE 10NUMBER
.46
«36.26 11
\
MOAB
NOTES:
•\~1 44 .104 .200 1. ONLY EVENTS OF MAGNITUDE
>
4.0 AND GREATER ARE SHOWN.
I
.193 \2. EARTHQUAKE RECORD: 1700 -
.15
MAY 14. 2012
\
W .42 .31
MONTICELLO.\
WHITE MESAMILL I PUEBLO
Z I
.64 I
J
-I'~~I
t:2J -11~6'
.148 /
230 "
.220 I N E W
LAS VEGAS"
;.216 •51 M/E X I C a4.55
~.198
GALLUP .232 /SANTA FE
~
~/
~/
l FLAGSTAFF
"'"
au
A R I Z
ALBUQUERQUE
~~.-/
-,~~
i ..------
»>--------SCALE
p -i
--ae I""""'""""'i22.5 22.5 50 MILES
f PROJECT
~OENISOJ)JJ (OJ)i
WHITE MESA MILL TAILINGS RECLAMATION MWH
~
me<
!
MINES HISTORICAL EARTHQUAKES
Denison Mines (USA) Corp
ocr
"
WITHIN 200 MILES MAY2012 FIGURE 1
FILENAME QUAKEDATA_DM
FIGURE 2
QI.h\KE o.o.TAeoMILEB
«D>MWH
SCALE
Fll£w.ME
""n:MAY 2012
LEGEND
EARTHQUAKES
•MAGNITUDE 2.0-2.9
•MAGNITUDE3.0-3.9
•MAGNITUDE 4.0-4.9
300 EARTHQUAKE ID NUMBER
NOTES:
1. ONLY EVENTS OF MAGNITUDE
2.4 AND GREATER ARE SHOWN.
2. EARTHQUAKE RECORD: 1973 -
MAY 14, 2012
-§-u.s.HIGHWAY
-8-STATEHIGHWAY
---STATE BOROER
o
HISTORICAL EARTHQUAKES
WITHIN 8D MILES
D 0
WHITE MESA MILL TAILINGS RECLAMATION
PROJECT
w
cI
E
X
A
MONTROSE -----...
•G
N
E
gENISOJ)~~
MINES
Denison Mines (USA) Corp
L
M
oc
-
MONTICELLO
L"G ~
WHITE MESA MILL
333
334
337
.305
.303
307
324308
/
/
8~,,~~~y.304
/
/
H I
/
!
I
I
\
\
\
\
AT
\.338
\
\-.-.
I Z 0 N ~<,8
GD 8 <,
------------
u
A~~
~~~
i11--------"---~=----------------.£...-------!....---...l...-___r------~~------.JL-,...-----~
t""L..------l..--====::..::.::..:=--L-~===___..E::::::===:J
.
~s
USGS DEAGGREGATION OF EARTHQUAKEHAZARD FOR 2,475 YEAR RETURN PERIOD FIGURE 3
DEAGG 2475 YRP
WHITE MESA MILL TAILINGS RECLAMATION
Denison Mines (USA) Corp MAY 2012
USGS DEAGGREGATION OF EARTHQUAKEHAZARD FOR 9,900 YEAR RETURN PERIOD FIGURE 4
DEAGG 9901 YRP
WHITE MESA MILL TAILINGS RECLAMATION
Denison Mines (USA) Corp MAY 2012
Sp
e
c
t
r
a
l

A
c
c
e
l
e
r
a
t
i
o
n

(
g
)
USGS SPECTRAL RESPONSE2,475 YEAR RETURN PERIOD FIGURE 5
SPECTRAL 4275 Y RETURN
WHITE MESA MILL TAILINGS RECLAMATION
Denison Mines (USA) Corp MAY 2012
Sp
e
c
t
r
a
l

A
c
c
e
l
e
r
a
t
i
o
n

(
g
)
USGS SPECTRAL RESPONSE9,900 YEAR RETURN PERIOD FIGURE 6
SPECTRAL 9901 Y RETURN
WHITE MESA MILL TAILINGS RECLAMATION
Denison Mines (USA) Corp MAY 2012

ATTACHMENT 1

WHITE MESA URANIUM FACILITY, CELL 4 SEISMIC STUDY, BLANDING, UTAH

MFG, INC., 2006

November 27, 2006 MFG Project No. 181413x.102

Mr. Harold R. Roberts
International Uranium (USA) Corporation
1050 Seventeenth Street, Suite 950
Denver, CO 80265

Subject: White Mesa Uranium Facility
Cell 4 Seismic Study
Blanding, Utah

Dear Mr. Roberts:

This document has been prepared to examine the seismicity of the White Mesa site and to recommend a
design peak ground acceleration (PGA) to be incorporated in the Cell 4A design. This letter addresses
concerns brought forth in comments by Utah Department of Environmental Quality (UDEQ) as documented
in Interrogatory IUC R313-24-4-05/05: Dike Integrity.

Comments in Interrogatory IUC R313-24-4-05/05
Comments from UDEQ state that the seismic loading used (0.10 g) for stability analysis of the Cell 4A slopes
is based on an outdated seismic analysis presented in the 1988 Cell 4 Design Report (UMETCO), and that
updated seismic hazard analysis should be performed. As stated in the Interrogatory 05, it is not thought that
there is any new information on active faults that would impact the hazard at White Mesa. However, UDEQ
requested ground motion attenuation relationships be updated to reflect current evaluation methods.

Original Design Basis for Cell 4
This original design report for Cell 4 (UMETCO, 1988), characterized the geologic conditions at the site.
Section 1.3.4 identified potential earthquake hazards to the project. The specified hazards include minor
random earthquakes not associated with a known seismic structure, and an unnamed fault located 57 km north
of the project site (north of Monticello), with a fault length well defined for 3 km, and possibly as long as 11
km. The fault is considered a suspected Quaternary fault, but does not have strong evidence for Quaternary
movement. Estimates of the maximum credible earthquake (MCE) associated with this fault were estimated
to have a magnitude of 6.4 based on relationships developed by Slemmons in 1977. Ground motions at the
project site were estimated using attenuation curves established in 1982 by Seed and Idriss. Peak horizontal
accelerations at the site from the fault were estimated to be 0.07 g.

MFG, Inc.

A TETRA TECH COMPANY

Fort Collins Office 3801 Automation Way, Suite 100
Fort Collins, CO 80525
970.223.9600
Fax: [phone]
Mr. Harold R. Roberts
November 27, 2006
Page 2
L:\Denison Mines\6.0 Studies & Reports\6.1 Reports\6.1.2 Other Reports (by others)\Tetra Tech - Seismicity Report\SeismicLetterReport Final.doc
Updated attenuation relationships
A search of the Quaternary Fault and Fold Database (USGS 2006) lists Shay graben faults as a Class B
(suspected) Quaternary fault. No other faults within 50 km of the site are included in the database. Shay
graben faults were included in the Lawrence Livermore National Laboratory (LLNL) report. Other faults
considered as possible seismic sources include the unnamed fault north of Monticello that was the design
basis of the design accelerations in the 1988 report.

Many attenuation relationships have been developed within the last ten years and are currently being used to
estimate ground motions. Three relationships are used in this report to estimate the peak ground motion at the
White Mesa site. Abrahamson and Silva (1997) is a well accepted relationship used for shallow crustal
earthquakes in Western North America. In addition, Spudich et al. (1999) is used because it has been
specifically developed for extensional tectonic regimes, such as those encountered in the area of the site.
Campbell and Bozorgnia (2003), is also examined as a current, applicable model, which accounts for normal
faulting. In all cases, mean values plus one standard deviation are reported. A comparison of the three
methods can be found in Table 1.

Design Peak Ground Acceleration for Cell 4
The above discussion is based on the PGA associated with MCE predicted for a known tectonic feature, and
as such, cannot be correlated to a specific return period. 10 CFR 100 Appendix A and 10 CFR 40 Appendix
A of Nuclear Regulatory Commission (NRC) regulations are interpreted to apply to long-term, reclaimed
impoundments. A distinction should be made between seismic conditions that apply to operational conditions
versus long-term conditions. Disposal areas are required to demonstrate closure performance that provides
control of radiological hazards to be effective for one thousand years, to the extent reasonably achievable,
and, in any case, for at least 200 years. However, this standard should not apply to the operational time-
period of the disposal cell. In 2002, the USGS updated the National Seismic Hazard Maps (NSHM), which
show peak ground and spectral accelerations at 2 percent and 10 percent probability of exceedance in 50
years. From these maps, the PGA for the White Mesa site is shown to be 0.090 g with a 2 percent probability
of exceedance in 50 years. The probability of exceedance can be represented by the following equation:
)/(1 TnePE−−=
Where PE = probability of exceedance, n = time period, in years, and T = return period, in years.
It can be shown that the return period associated with a PGA of 0.090 g is equivalent to 2,475 years, and if the
life of the project is conservatively taken to be 100 years, the probability of exceedance of 0.090 g is
approximately 4 percent. Therefore, the PGA taken from the USGS maps is an appropriate design
acceleration to use for operational conditions of the disposal cell.
Conclusions
The seismic loading of 0.1 g used in analysis of the Cell 4A dikes exceeds the PGA associated with a 2
percent probability of exceedance within 50 years, and is appropriate for the operational life of the disposal
cell. At the time when design of closure is implemented, design PGA based on the MCE associated with
known or suspected Quaternary features and the background seismicity of the area should be incorporated
into the design long-term seismic loading.
Mr. Harold R. Roberts
November 27, 2006
Page 3
L:\Denison Mines\6.0 Studies & Reports\6.1 Reports\6.1.2 Other Reports (by others)\Tetra Tech - Seismicity Report\SeismicLetterReport Final.doc
References
Abrahamson, N.A., and W.J. Silva (1997). Empirical Response Spectral Attenuation Relations for Shallow
crustal Earthquakes, Seismologcal Research Letters, Vol. 68, No. 1, pp. 94-127, January/February.

Campbell, K.W., and Y. Bozorgnia (2003). Updated Near-Source Ground-Motion (Attenuation) Relations for
the Horizontal and Vertical Components of Peak Ground Acceleration and Acceleration Response Spectra,
Bulletin of the Seismological Society of America, Vol. 93, No. 1, pp. 314-331, February.

Spudich, P., W.B. Joyner, A.G. Lindh, D.M. Boore, B.M. Margaris, and J.B. Fletcher (1999). SEA99: A
Revised Ground Motion Prediction Relation for Use in Extensional Tectonic Regimes, Bulletin of the
Seismological Society of America, Vol. 89, No. 5, pp. 1156-1170, October.

UMETCO, 1988. Cell 4 Design, Appendix A, White Mesa Project.

U.S. Geological Survey (USGS) 2002. Quaternary Fault and Fold Database: http://Qfaults.cr.usgs.gov/.

If we can be of further assistance, please do not hesitate to contact the undersigned.

Sincerely,

TETRA TECH COMPANY
MFG, INC.

Roslyn Stern
Senior Staff Geotechnical Engineer

Reviewed by:

Thomas A. Chapel, CPG, PE
Senior Geotechnical Engineer

cc: Tetra Tech EMI
Ms. JoAnn Tischler

Attachment(s)

Table 1: Peak Ground Accelerations – White Mesa
Name
Fault
Length
(km)
Fault
Type1
Site
Class2
Distance
from
site (km)
MCE (Wells
and
Coppersmith,
1994)
PGA Mean
plus 1 SD
(Spudich et
al., 1999)
PGA Mean
plus 1 SD
(Abrahamson
and Silva,
1997)
PGA Mean
plus 1 SD,
Campbell-
Bozorgnia
2003
PGA Mean
plus 1 SD
average
unnamed fault north of Monticello,
defined length 3.0 N R 57.4 5.49 0.034 0.027 0.037 0.032
unnamed fault north of Monticello,
possible total length 11.0 N R 57.4 6.23 0.050 0.059 0.055 0.055
unnamed fault north of Monticello,
1/2 total rupture 5.5 N R 57.4 5.84 0.041 0.039 0.044 0.041
Shay graben faults (Class B) 40.0 N R 44.6 6.97 0.096 0.116 0.113 0.108
1Fault Type: N = Normal 2Site Class: R =Rock or shallow soils

ATTACHMENT 2

TECHNICAL MEMORANDUM RE: WHITE MESA URANIUM FACILITY, SEISMIC STUDY
UPDATE FOR A PROPOSED CELL, BLANDING UTAH

TETRA TECH, INC., 2010

['11;)TETRA TECH
Technical Memorandum
380I AutomationWay Suite 100
Fort Collins CO 80525
TeI 970.223.9600 Fax [phone]
www.tetratech.com
To:Mr. Harold R.Roberts Heather Trantham,Ph.D., P.E.
From:Senior Staff Geotechnical
Engineer
Company:Denison Mines (USA) Corp
1050 Seventeenth Street,Suite 950
Denver,CO 80265
Date:February 3, 2010
Reviewed
by:
Re:White Mesa Uranium Facility
Seismic Study update for a Proposed Cell
Blanding ,Utah
Project #:114-182018
Introduction
Denison Mines (USA) Corp is proposing to add a new uranium containment cell to the facility at
Blanding,Utah. This document was prepared to address seismic concerns brought forth in
comments by the UDRC as documented in the second round of Interrogatories.This seismic
hazard analysis has been prepared as an update to the previous seismic study performed for the
site by Tetra Tech (formerly MFG,2006).
Project Location
The project is located near Blanding,Utah.For the purposes of these analyses,the latitude and
longitude of 37.5°N and 109.5QW,respectively,were used.
Previous Work
Seismicity of the White Mesa site has been investigated in two previous reports. The original
design report for Cell 4 was prepared in 1988 by UMETCO. The geologic conditions and the
1
(-n:)TETRA TECH
potential seismic hazards were characterized in that report.The specified hazards include minor
random earth quakes not associated with a
known seismic structure,and an unnamed fault located 57 km north of the project site (north of
Monticello),with a fault length well defined for 3 km,and possibly as long as 11 km. The fault is a
suspected Quarternary fault,but does not have strong evidence for Quaternary movement.The
maximum credible earthquake (MCE)associated with this fault was estimated to have a magnitude
of 6.4 based on relationships developed by Siernmons in 1977. Ground motions at the project site
were estimated using attenuation curves established in 1982 by Seed and Idriss.Peak horizontal
acce lerations at the site from the fault were estimated to be 0.07 g.
In 2006 an additional seismic study was prepared to recommend a design peak ground
acce leration (PGA)to use during the operational period for the design of Cell 4A at the site. A
search performed as part of that study found one additional suspected Quaternary fault in the
USGS (2006) Quaternary Fault and Fold Database.The search was performed for a region within
50 km of the site. The database lists the'Shay graben fault as a Class B (suspected) Quaternary
fault. In the report updated attenuation relationships were used to estimate ground motions and
then compared:Abrahamson and Silva (1997),Spudich et al.(1999),and Campbell and Bozorgnia
(2003). The design Peak Ground 'Acceleration (PGA) for Cell 4 was determined to be 0.09 g
based on the 2002 USGS National Seismic Hazard Maps (NSHM) with a 2 percent probability of
exceedance in 50 years.The report concluded that the seismic loading of 0.1g used in the analysis
of Cell 4A associated with a 2 percent probability of exceedance within 50 years was appropriate
for the operational life of the disposal cell.
The following sections address requests sent to Denson Mines (USA)Corp in an email from URS
dated January 20,2010.In addition to the information presented below,the information by
Brumbaugh (2005) that was referenced in the email was also reviewed.
Regional Physiographic and Tectonic Setting
The site is located within the Colorado Plateau physiographic province in southeastern Utah.The
Colorado Plateau is a broad, roughly circular region of relative structural stability within a more
structurally active region of disturbed mountain systems.Broad basins and uplifts,monoclines,
and belts of anticlines and synclines are characteristic of the plateau (Kelley, 1979).
The White Mesa site is located near the western edge of the Blanding Basin,east of the north-
south trending Monument Uplift,south of the Abajo Mountains.It is also adjacent to the northwest
trending Paradox Fold.
The contemporary seismicity of the Colorado Plateau was investigated by Wong and Humphrey
(1989)based on seismic monitoring.Their study characterized the seismicity of the plateau as
being of small to moderate magnitude, of a low to moderate rate of occurrence with earthquakes
widely distributed.Seismicity in the plateau appea rs to be the result of the reactivation of
preexisting faults not expressed at the surface but favorable oriented to the tectonic stress field.
Very few earth quakes can be associated with known geologic structures or tectonic features in the
plateau.The generally small size of the earthquakes and their widespread distribution is consistent
with a highly faulted Precambrian basement and upper crust,and a moderate level of differential
tectonic stresses. Earthquakes in the plateau generally occur within the upper 15 to 20 km of the
2
('"It::)TETRA TECH
upper crust (Smith, 1978, Wong and Chapman,1986) although events have occurred as deep as
58 km (Wong and Humphrey,1989).The predominant mode of tectonic deformation within the
plateau appears to be normal faulting on the northwest-to north-northwest-striking faults,with
some localized occurrences of strike-slip displacement on the northwest- or northeast-striking
planes at shallow depths. The contemporary state of stress within the plateau is characterized by
approximately northeast-trending extension (Wong and Humphrey,1989).
Seismicity
Earthquake Catalogs
The seismic hazard analysis for the site included a review of historic earthquakes which have
occurred within 200 miles of the site.A radius of 200 miles is recommended by the Senior Seismic
Hazard Analysis Committee (SSHAC,1997) and the NRC (2007).The NEIC database was used
and includes all recorded seismic events over a period from 1850 through January 2010.The
database search was performed to incorporate the most recent seismic events in the region and to
verify that estimated ground accelerations from all known events are below the design peak
acceleration recommended in this report.
The largest eve nt is estimated in the NOAA catalog to have an Mw of 5.8. This event occurred
near Smithfield, Utah on August 30, 1962. The epicenter is approximately 200 miles northwest of
the site.
The event closest to the site had an epicenter about 40 miles northwest of the site. This
earthquake,which occurred on February 23,1968 had an Mw of 2.8.
The list of earthquakes as described above is included in Appendix 1.
accelerations for the five most significant earthquakes on the list were
discussed below.
Seismic Hazard Analysis
The peak ground
calculated and are
Seismic hazard analyses are typically conducted using one of two methods: (1) deterministic
analysis or (2)probabilistic analysis (SSHAC,1997).In the deterministic analyses, the ground
motions from the maximum credible earthquake (MCE)associated with capable faults are
attenuated to the site.The ground motions from the MCE associated with the fault are attenuated
to the site using established attenuation equations. Deterministic analysis was used in this seismic
update and is described in the next section.
In probabilistic analyses,ground motions and the associated probability of exceedance are
estimated in order for the amount of risk associated with the design ground motion to be evaluated.
As specified by the U.S.Environmental Protection Agency (EPA)Promulgated Standards for
Remedial Actions at Inactive Uranium Processing Sites (40 CFR 192),the controls of residual
radioactive material are to be effective for up to 1,000 years,to the extent reasonably achievable
and,in any case,for at least 200 years.For the purpose of the seismic hazard evaluation,a
10,000-year return period is adopted for evaluating long-term stability of the facility.The probability
that the 10,000-year event will be exceeded within a 200- to 1,ODD-year design life is between 2
3
(-n:)TETRA TECH
and 10 percent.This is consistent with the International Building Code (IBC,2006)which specifies
designing for ground motions associated with a 2 percent probability of exceedance in a 50-year
design life, or a return period of approximately 2,500 years.Similarly,a 2,500-year return period is
appropriate during operational conditions considering a design life of 50 years.
The probability of exceedance can be represented by the following equation:
where PE is the probability of exceedance,n is the time period in years,and T is the return period
in years.
Using the most recent USGS National Seismic Hazard Maps (NSHM,2008), with a 10,000 year
return period,and the probability of exceedance of 2%for a 200-year design life,the PGA for the
site was determined to be 0.15 g. The shear wave velocity (v,)used for the deaggragation
calculation 586 m/s which corresponds to 1923 1Vs. Site Class Definitions are listed for the top 100
feet of the soil profile in Table 1613.5.2 of the International Building Code (IBC,2006).For soils
having a Standard Penetration Resistance (N-value)between 15 and 50,the shear wave velocity
ranges between 600 and 1,200 IVs.In conjunction with previous work at the site,Tetra Tech
(formerly MFG) drilled a borehole at the site on June 15,2006.The Standard Penetration values
from borehole MFG-1 range from N=33 to N=50/5".The shear wave velocity chosen for the top 31'
was 200 m/s (656 IVs).For the remaining 69', a shear wave velocity of 760 m/s (2493 flls)
corresponding to sandstone was chosen.The weighted average of the shear wave velocity for the
top 100 It was 586 m/s (1923 flls).The borehole log for MFG-1 is presented in Appendix 2.The
data from USGS National Seismic Hazards Mapping Project,2008 Version PSHA Deaggregation
are presented in Appendix 3.
Earthquakes occur that are not associated with a known structure.These events are termed
background events,or floating earthquakes. Evaluation of the background event allows for
potential low to moderate earthquakes not associated with tectonic structures to contribute to the
seismic hazard of the site.The maximum magnitude for these background events within the
Intermountain U.S. ranges between local magnitude (Me)6.0 and 6.5 (Woodward-Clyde,1996).
Larger earthquakes would be expected to leave a detectable surface expression, especially in arid
to semiarid climates,with slow erosion rates and limited vegetation.In seismically less active
areas such as the Colorado Plateau, the maximum magnitude associated with a background event
is assumed to be 6.3, consistent with that used in seismic evaluations performed for uranium tailing
sites in Green River (DOE 1991a, pg.26), and Grand Junction (DOE 1991b,pg.7 1).A study by
Wong et al (1996)also evaluated the recurrence of background events within the Colorado
Plateau. Wong et al.(1996)suggests that the maximum background earthquakes as large as Mw
could occur,although they are unlikely.In this update,an arbitrary event (Mw = 6.3,radial distance
= 15 km)was analyzed using the most recent Campbell and Bozorgnia (2007) attenuation
relationship. Results are described in the following section
Attenuation Relationships
In the previous study (MFG,2006)three attenuation relationships to estimate the peak ground
motion at the White Mesa site were used:Abrahamson and Silva (1997),Spudich et al.(1999),
4
('"R::)TETRA TECH
and Campbell and Bozorgnia (2003). Since this report, Campbell and Bozorgnia have updated
their 2003 model into a Next Generation Attenuation (NGA) Project (2007). The NGA model
included the input of several other modelers and is considered an update to Abrahamson and Silva
(1997), Boore, et al.(1997),Sadigh,et al.(1997),Idriss (1993 and 1996), and (Campbell and
Bozorgnia (2006). The faults chosen for the analysis include the unnamed fault north of Monticello
that was the basis of the design acceleration in the 1988 report,and the Shay graben faults (USGS
2006)a Class B (suspected) Quaternary fault that was included in the 2006 report.Additionally the
earthquakes in the earthquake catalog created for the site were considered.The earthquakes that
were considered have a calculated magnitude.The calculation of the rnagnitude of these
earthquakes was not perforrned as part of this study. The accelerations felt at the White Mesa site
due to these recorded events are listed in Table 1 for the 5 most relevant events. For comparison,
an arbitrary event occurring 15 km from the site with a rnagnitude of 6.3 is used to account for the
floating earthquake at the White Mesa site. The results for attenuation relations as calculated
using Carnpbell and Bozorgnia NGA (2007) plus one standard deviation are reported are
presented in Table 1. Spreadsheets detailing the calculations are included in Appendix 4.
5
(1't:)TETRA TECH
Table1 .Peak Ground Accelerations for White Mesa
Fault Distance
Name Length Fau lt Site from Site MCE(3)PGA(4)Type!')Class(2)
(km)(km)
Unnamedfault north of
Monticello (possible 3.0 N R 57.4 5.49 0.038extensionof Shays
graben) defined length
Unnamed fault north of
Monticello (possible
extension of Shays 11.0 N R 57.4 6.23 0.063
graben)total possible
length
Unnamed fault north of
Monticello (possible 5.5 N R 57.4 5.84 0.049extensionof Shays
oraben)Y2 total rupture
Shay graben faults 40.0 N R 44.6 6.97 0.090.(Class Bl
Earthquake on 2/21/54 -- -70 4.7 0.012fromEPBcatalog
Earthquake on 1/30/89 ---147 5.4 0.011fromPOEcatalog
Earthquake on 2/3/95 - --139 5.3 0.011fromPOEcataloc
Earthquake on 10/11 /77 -- -74 4.7 0.011from POEcataloo
Earthquake on 10/11 /60 ---189 5.5 0.01fromSRAcatalog
Floatinq Earthquake ---15 6.3 0.243
(1)Fault Type:N=Normal
(2) Site Class:R =Rock or shallowsoils
(3) Wells andCoppersmith,1994
(4)Campbe ll and Bozorgnia NGA,2007
Conclusion
Using the most recent USGS National Seismic Hazard Maps (NSHM,2008),with a 10,000 year
return period, and the probability of exceedance of 2%for a 200-year design life,the PGA for the
site was determined to be 0.15 g.Based on the most current USGS Geological Survey Earthquake
Hazards Program National Maps (2008), and using the attenuation relationship of Campbell and
Bozorgnia (2007), this PGA of 0.15 g is reasonable for the White Mesa site.This maximum PGA is
a peak value.For a pseudo-static analysis,and in accordance with IBC 2006,the PGA should be
multip lied by 0.667 to determine a design acceleration value.Therefore the design acceleration
value for the White Mesa site is calculated to be 0.1. This value is consistent with the previous
design value that was computed in the previous analysis for the site.
6
(-n:)TETRA TECH
References
40 CFR 192.U.S .Environmental Protection Agency,"Health and Environmental
Protection Standards for Uranium and T horium Mill Tailings."
Abrahamson,N.A.,Silva,W.J.(1997) Empirical Response Spectral Attenuation Relations for
Shallow Crustal Earthquakes.Seismological Research Letters 68(1 ):94:127.
Brumbaugh,D.S.(2005) Active Faulting and Seismicity in a Prefractured Terrane:Grand Canyon,
Arizona.Bulletin of the Seismological Society of America 95: 1561-1566.
Bryant,W.A, and Sander,E.G.(2008) National Quaternary Fault and Fold Database Data
Compilation for the State of California, National Quaternary Fault and Fold Database
Compilation for the State of California.
Campbell,K.W.and Bozorgnia,Y. (2003)Updated near-Source Ground-Motion (Attenuation)
Relations for the Horizontal and Vertical Components of Peak Ground Acceleration and
Acceleration Response Spectra.Bulletin of the Seismological Society of America
93(1):314-331.
Campbell,KW .and Bozorgnia Y.(2006) Carnpbell-Bozorgnia NGA Empirical Ground Motion
Model for the Average Horizontal Component of PGA,PGV and SA at Selected Spectral
Periods Ranting from 0.01-10 Seconds.Workshop on Implementation of the Next
Generation Attenuation Relationships (NGA) in the 2007 Revision of the National Seismic
Hazard Maps.PEER Center,Richmond,CA September 25-26.
Campbell,K.W.and Bozorgnia,Y.(2007) NGA Ground Motion Relations for the Geometric Mean
Horizontal Component of Peak and Spectra Ground Motion Parameters.Pacific
Earthquake Engineering Research Center Report 2007/02,246 p.
DOE (U.S. Department of Energy (1991a)Remedial Action Plan and Final Design for Stabilization
of the Inactive Uranium Mill Tailings at Green River,Utah.
DOE (U.S.Department of Energy)(1 991b)Remedial Action Plan and Site Design for Stabilization
of the Inactive Uranium Mill Tailings Site at GrandJunction,Colorado.
International Building Code (2006) International Code council,Inc.
Kelley, V.C.(1979)Tectonics of the Colorado Plateau and New Interpretation of Its Eastern
Boundary.Tectonophysics 61:97-102.
NRC (2007) A Performance-Based Approach to Define the Site-Specific Earthquake Ground
Motion.RegulatoryGuide 1.208 March 2007.
Senior Seismic Hazard Analysis Committee (SSHAC)(1997) Recommendations for Probabilistic
Seismic Hazard Analysis-Guidance on Uncertainty and Use of Experts:U.S. Nuclear
Regulatory Commission NUREG/CR-6327.
7
(-n:)TETRA TECH
Slemmons,D.B. (1997) State-of-the-Art for Assessing Earthquake Hazards in the United States:
Report 6. Faults and Earthquake Magnitude:U.S. Army Engineer Waterways Experiment
Station Miscellaneous Paper S-73-1 ,129 p., 37 p.
Smith, R.B. (1978) Seismicity,Crustan Structure and Interplate Tectonics of the Interior of the
Western Cordillera,in Smith R.B., and Eaton,G.P.eds.,Cenozoic Tecctonics and Regional
Geophysics of the Western Cordillera:Geological Society of America Memoir 152:111 -
144.
Spudich, P.,Joyner,W.B.,Lindh,D.M.,Boore,D.M.,Margaris,B.M., and Fletcher,J.B. (1999)
SEA99:A Revised Ground Motion Prediction Relation for Use in Extensional Tectonic
Regimes.Bulletin of the Seismological Society of America Vol. 93,No.1,pp.314-331 ,
February.
Tetra Tech,Inc.(formerly MFG)(2006) White Mesa Uranium Uranium Facility Cell 4 Seismic
Study,Blanding Utah.MFG Project No.181413x.1 02 dated November 27.
USGS (2008) Earthquake Hazards Program:United Stated National Seismic Hazard Maps
Program (NSHMP).May 2008
http://earthguake.usgs.gov/hazards/productsiconterminousi2008/
UMET CO (1988)Cell 4 Design,Appendix A,White Mesa Project.
Woodward-Clyde Consultants (1996)Evaluation and Potential Seismic and Salt Dissolution
Hazards at the Atlas Uranium Mill Tailings Site,Moab Utah,Oakland,California,
unpublished Consultant's report for Smith Environmental Technologies and Atlas
Corporation, SK9407.
Wong,I.G.,and Chapman,D.S. (1986) Deep Intraplate Earthquakes in the Intermountain U.S.:
Implications to Thermal and Stress Conditions in the Lower Crust and Upper Mantle,
Earthquake Notes 57:6.
Wong,I.G.and Humphrey,H.R. (1989) Contemporary Seismicity, Faulting, and the State of Stress
in the Colorado Plateau:Geological Society of America Bulletin, v.101,p. 1127-1146.
Wong,I.G.,Olig,S.S.,and Bott,J.D.J.(1996)Earthquake Potential and Seismic Hazards in the
Paradox Basin,Southeastern Utah,in A.C.Huffman,W.R.Lund, and L.H.Godwin,eds.,
Geology and Resources of the Paradox Basin,1996 Special Symposium,Utah Geological
Association and Four Corners Geological Society Guidebook 25:241-250.
8

APPENDIX 1: EARTHQUAKE EVENTS WITHIN 200
MILES OF THE WHITE MESA SITE

Appendix 1: Earthquake Events within 200 miles of the White
Mesa Site

Source: NEIC Database

Magnitude Year Month Day
Latitude
(degree,
North)
Longitude
(degree,
West) Magnitud
e
Radial
Distanc
e
(km)
Catalog
NOAA 1962 8 30 41.8 -111.8 5.8 320 0.007
SRA 1973 5 17 39.79 -108.37 5.7 272 0.008
PDE 1973 5 17 39.79 -108.37 5.7 180
0.012 (man
made)
SRA 1959 7 21 36.8 -112.37 5.6 266 0.007
EPB 1962 8 30 41.8 -111.8 5.6 320 0.006
USHIS 1959 7 21 36.8 -112.37 5.6 266 0.007
SRA 1960 10 11 38.3 -107.6 5.5 189 0.01
USHIS 1960 10 11 38.3 -107.6 5.5 189 0.01
USHIS 1967 10 4 38.54 -112.16 5.5 260 0.007
PDE 1989 1 30 38.82 -111.61 5.4 147 0.011
PDE 1988 8 14 39.13 -110.87 5.3 141 0.01
PDE 1995 2 3 41.53 -109.64 5.3 139 0.011
EPB 1894 7 18 41.2 -112 5.3 284 0.004
USHIS 1988 8 14 39.128 -110.869 5.3 216 0.006
USHIS 1989 1 30 38.824 -111.614 5.3 236 0.006
SRA 1921 9 29 38.7 -112.1 5.2 263 0.004
SRA 1967 10 4 38.54 -112.16 5.2 260 0.004
EPB 1950 1 18 40.5 -110.5 5.2 140 0.009
USHIS 1921 9 29 38.7 -112.1 5.2 263 0.004
SRA 1966 1 23 36.98 -107.02 5.1 227 0.004
PDE 1977 9 30 40.52 -110.44 5.1 279 0.003
EPB 1962 9 5 40.7 -112 5.1 251
SRA 1959 10 13 35.5 -111.5 5 285
EPB 1884 11 9 41.5 -111.2 5 264
EPB 1910 5 22 40.8 -112 5 257
EPB 1915 7 15 40.3 -111.7 5 207
EPB 1943 2 22 41 -111.5 5 238
EPB 1950 2 25 40 -112 5 221
EPB 1953 5 23 40.5 -111.5 5 203
EPB 1958 2 13 40.5 -111.5 5 203
USHIS 1959 10 13 35.5 -111.5 5 285
USHIS 1963 7 7 39.53 -111.91 4.9 307
USHIS 1966 1 23 36.98 -107.02 4.9 227
SRA 1962 2 5 38.2 -107.6 4.7 184
PDE 1977 10 11 40.49 -110.49 4.7 74 0.011
PDE 2003 4 17 39.52 -111.86 4.7 281
EPB 1954 2 21 40 -109 4.7 70 0.012
EPB 1958 12 1 40.5 -112.5 4.7 279
USHIS 1962 2 5 38.2 -107.6 4.7 184
SRA 1976 1 5 35.84 -108.34 4.6 211
PDE 1994 9 13 38.15 -107.98 4.6 140
EPB 1949 3 7 40.8 -111.9 4.6 250
USHIS 1976 1 5 35.817 -108.212 4.6 219
SRA 1962 2 15 36.9 -112.4 4.5 265
SRA 1962 6 5 38 -112.1 4.5 235
PDE 1983 10 8 40.75 -111.99 4.5 177
PDE 1998 1 2 38.21 -112.47 4.5 279
EPB 1950 1 2 41.5 -112 4.5 306
EPB 1956 10 3 41.5 -110.1 4.5 227
EPB 1958 1 5 41 -112.5 4.5 304
USHIS 1962 2 15 36.9 -112.4 4.5 265
USHIS 1962 6 5 38 -112.1 4.5 235
SRA 1962 1 13 38.4 -107.8 4.4 179
SRA 1962 2 15 37 -112.9 4.4 306
SRA 1963 7 7 39.53 -111.91 4.4 307
SRA 1972 1 3 38.65 -112.17 4.4 266
SRA 1986 3 24 39.234 -112.062 4.4 295
PDE 1986 3 24 39.24 -112.01 4.4 275
PDE 1992 6 24 38.78 -111.55 4.4 140
PDE 2000 1 30 41.46 -109.68 4.4 263
EPB 1957 10 26 40 -111 4.4 139
USHIS 1972 1 3 38.65 -112.17 4.4 266
USHIS 1986 3 24 39.236 -112.009 4.4 291
USHIS 1988 8 18 39.132 -110.867 4.4 216
SRA 1963 9 30 38.1 -111.22 4.3 165
PDE 1994 9 6 38.08 -112.33 4.3 140
PDE 1999 4 6 41.45 -107.74 4.3 262
PDE 2000 5 27 38.34 -108.86 4.3 185
PDE 2001 7 19 38.73 -111.52 4.3 142
PDE 2002 1 31 40.29 -107.69 4.3 191
EPB 1880 9 16 40.8 -112 4.3 257
EPB 1899 12 13 41 -112 4.3 270
EPB 1906 5 24 41.2 -112 4.3 284
EPB 1910 7 26 41.5 -109.3 4.3 222
EPB 1915 8 11 40.5 -112.7 4.3 294
EPB 1916 2 4 40 -111.7 4.3 196
EPB 1920 9 18 41.5 -112 4.3 306
EPB 1950 5 8 40 -111.4 4.3 171
EPB 1952 9 28 40.2 -111.5 4.3 187
EPB 1955 2 2 40.8 -111.9 4.3 250
EPB 1955 2 10 40.5 -107 4.3 240
EPB 1955 5 12 41 -112 4.3 270
EPB 1957 7 18 40 -110.5 4.3 102
EPB 1962 9 4 41.7 -111.8 4.3 312
EPB 1966 3 17 41.7 -111.5 4.3 297
EPB 1967 2 14 40.1 -109 4.3 79
EPB 1967 9 23 40.7 -112.1 4.3 258
SRA 1966 5 8 37 -106.9 4.2 237
SRA 1967 9 4 36.15 -111.6 4.2 239
SRA 1977 3 5 35.91 -108.29 4.2 206
PDE 1973 7 16 39.15 -111.51 4.2 244
PDE 1980 5 24 39.94 -111.97 4.2 265
PDE 1989 2 27 38.83 -111.62 4.2 275
PDE 1992 3 16 40.47 -112.04 4.2 186
PDE 1996 1 6 39.12 -110.88 4.2 145
PDE 1998 6 18 37.97 -112.49 4.2 272
PDE 1999 10 22 38.08 -112.73 4.2 263
PDE 2000 3 7 39.75 -110.84 4.2 263
USHIS 1977 3 5 35.748 -108.222 4.2 225
SRA 1966 5 20 37.98 -111.85 4.1 213
SRA 1973 12 24 35.26 -107.74 4.1 294
PDE 1983 9 24 40.79 -108.84 4.1 291
PDE 1995 3 20 40.18 -108.93 4.1 140
PDE 2001 2 23 38.73 -112.56 4.1 309
PDE 2004 11 7 38.24 -108.92 4.1 281
USHIS 1973 12 24 35.26 -107.74 4.1 294
SRA 1963 7 9 40.03 -111.19 4 316
SRA 1967 2 15 40.11 -109.05 4 292
SRA 1971 11 12 38.91 -108.68 4 172
SRA 1972 6 2 38.67 -112.07 4 260
SRA 1982 5 24 38.71 -112.04 4 259
SRA 1986 8 22 37.42 -110.574 4 95
PDE 1982 5 24 38.71 -112.04 4 273
PDE 1986 8 22 37.42 -110.57 4 281
PDE 1987 12 16 39.29 -111.23 4 247
PDE 1992 7 5 39.32 -111.13 4 154
PDE 1998 1 30 37.97 -112.55 4 319
PDE 2001 8 9 39.66 -107.38 4 289
EPB 1960 7 9 41.5 -112 4 306
USHIS 1982 5 24 38.71 -112.04 4 259
SRA 1967 8 7 36.4 -112.6 3.9 301
SRA 1968 1 16 39.27 -112.04 3.9 296
SRA 1970 4 21 40.1 -108.9 3.9 293
SRA 1970 5 23 38.06 -112.47 3.9 268
USHIS 1986 3 25 39.223 -112.011 3.9 290
SRA 1971 1 7 39.49 -107.31 3.8 291
SRA 1979 4 30 37.88 -111.02 3.8 140
SRA 1963 6 19 38.02 -112.53 3.7 273
SRA 1963 7 10 40.02 -111.25 3.7 318
SRA 1966 7 6 40.09 -108.95 3.7 291
SRA 1970 4 18 37.87 -111.72 3.7 199
SRA 1971 7 10 40.24 -109.6 3.7 304
SRA 1971 11 10 37.8 -113.1 3.7 319
SRA 1975 1 30 39.27 -108.65 3.7 209
SRA 1984 8 16 39.392 -111.936 3.7 298
SRA 1967 7 22 38.8 -112.22 3.6 278
SRA 1968 9 24 38.04 -112.08 3.6 234
SRA 1969 4 10 38.66 -112.07 3.6 259
SRA 1972 11 16 37.53 -112.77 3.6 288
SRA 1983 12 9 38.577 -112.565 3.6 294
SRA 1965 6 7 36 -112.2 3.5 292
SRA 1966 4 23 39.1 -111.55 3.5 252
SRA 1966 5 8 36.9 -107 3.5 231
SRA 1968 11 17 39.52 -110.97 3.5 258
SRA 1974 11 4 38.34 -112.24 3.5 258
SRA 1976 4 19 35.39 -109.1 3.5 236
SRA 1978 2 24 38.33 -112.84 3.5 307
SRA 1979 1 12 37.73 -113.13 3.5 321
SRA 1979 10 23 37.89 -110.93 3.5 133
SRA 1981 5 14 39.48 -111.08 3.5 259
SRA 1984 3 21 39.344 -111.109 3.5 248
SRA 1962 12 11 39.36 -110.42 3.4 221
SRA 1963 4 15 39.59 -110.35 3.4 243
SRA 1966 6 1 36.9 -107 3.4 231
SRA 1981 1 16 37.45 -113.11 3.4 319
SRA 1983 8 14 38.359 -107.402 3.4 207
SRA 1963 4 24 39.44 -110.33 3.3 227
SRA 1963 8 16 39.48 -111.99 3.3 308
SRA 1964 1 17 38.19 -112.62 3.3 284
SRA 1965 1 14 39.44 -110.35 3.3 227
SRA 1966 12 19 39 -106.5 3.3 310
SRA 1968 6 2 39.21 -110.45 3.3 207
SRA 1969 5 23 39.02 -111.97 3.3 274
SRA 1978 12 9 38.66 -112.53 3.3 295
SRA 1978 12 9 38.65 -112.52 3.3 293
SRA 1981 1 16 37.45 -113.1 3.3 318
SRA 1981 8 8 38.05 -112.8 3.3 296
SRA 1982 3 5 37.37 -112.61 3.3 275
SRA 1983 1 27 37.778 -110.674 3.3 108
SRA 1983 8 31 36.135 -112.037 3.3 272
SRA 1985 4 14 35.174 -109.071 3.3 260
SRA 1986 10 5 38.631 -112.558 3.3 296
SRA 1962 8 19 38.05 -112.09 3.2 236
SRA 1963 11 13 38.3 -112.66 3.2 291
SRA 1965 1 30 37.54 -113.12 3.2 319
SRA 1965 6 29 39.5 -110.39 3.2 235
SRA 1966 4 14 37 -107 3.2 228
SRA 1967 10 25 39.47 -110.35 3.2 230
SRA 1973 2 9 36.43 -110.425 3.2 144
SRA 1974 4 29 37.81 -112.98 3.2 308
SRA 1977 2 9 39.29 -111.11 3.2 243
SRA 1977 6 3 39.65 -110.51 3.2 254
SRA 1979 10 6 39.29 -111.69 3.2 275
SRA 1980 12 21 37.53 -113.04 3.2 312
SRA 1981 9 21 39.59 -110.42 3.2 245
SRA 1982 2 12 37.41 -112.57 3.2 271
SRA 1984 5 14 39.322 -107.228 3.2 283
SRA 1986 5 14 37.294 -110.319 3.2 75
SRA 1962 9 7 39.2 -110.89 3.1 224
SRA 1964 8 24 38.77 -112.23 3.1 277
SRA 1964 9 6 39.18 -111.46 3.1 253
SRA 1964 11 29 38.97 -112.23 3.1 289
SRA 1966 7 30 39.44 -110.36 3.1 227
SRA 1970 2 21 39.49 -110.35 3.1 232
SRA 1970 10 25 39.17 -111.41 3.1 249
SRA 1971 4 22 39.41 -111.94 3.1 300
SRA 1971 6 23 38.61 -112.71 3.1 307
SRA 1976 8 13 38.42 -112.18 3.1 256
SRA 1976 11 26 39.51 -111.26 3.1 270
SRA 1979 3 19 40.18 -108.9 3.1 301
SRA 1981 9 10 37.5 -110.56 3.1 93
SRA 1983 3 22 39.546 -110.422 3.1 240
SRA 1984 4 22 39.281 -107.19 3.1 282
SRA 1963 12 24 39.56 -110.32 3 239
SRA 1964 8 5 38.95 -110.92 3 203
SRA 1964 9 21 38.8 -112.21 3 277
SRA 1965 7 13 37.71 -112.98 3 308
SRA 1965 7 20 38.03 -112.44 3 265
SRA 1965 9 10 39.43 -111.47 3 274
SRA 1967 4 4 38.32 -107.75 3 178
SRA 1968 3 20 37.92 -112.28 3 249
SRA 1970 4 14 39.65 -110.82 3 264
SRA 1970 11 24 36.357 -112.273 3 277
SRA 1971 12 15 36.791 -111.824 3 220
SRA 1973 1 22 37.19 -112.97 3 309
SRA 1976 2 28 35.91 -111.788 3 269
SRA 1977 9 24 39.31 -107.31 3 277
SRA 1977 11 29 36.82 -110.99 3 152
SRA 1978 5 29 39.28 -107.32 3 274
SRA 1978 9 23 39.32 -111.09 3 245
SRA 1981 5 29 36.83 -110.37 3 107
SRA 1981 7 14 36.82 -110.31 3 104
SRA 1981 9 22 39.59 -110.39 3 244
SRA 1982 4 17 38.22 -111.3 3 177
SRA 1982 11 3 35.32 -108.74 3 251
SRA 1982 11 19 36.03 -112.01 3 277
SRA 1983 5 3 38.305 -110.633 3 133
SRA 1984 6 12 39.143 -107.394 3 259
SRA 1984 7 18 36.216 -111.844 3 252
SRA 1985 6 27 39.558 -110.396 3 241
EPB 1930 7 28 41.5 -109.3 3 222
SRA 1963 1 10 39.5 -110.33 2.9 233
SRA 1963 9 2 39.62 -110.4 2.9 247
SRA 1964 2 6 37.65 -112.97 2.9 306
SRA 1964 6 6 39.6 -110.37 2.9 245
SRA 1964 8 12 39.15 -112.16 2.9 295
SRA 1965 1 18 37.97 -112.85 2.9 299
SRA 1965 3 26 39.42 -110.28 2.9 223
SRA 1965 5 29 39.29 -110.35 2.9 212
SRA 1966 5 1 39.08 -111.56 2.9 251
SRA 1969 3 13 39.55 -110.41 2.9 240
SRA 1969 11 12 37.77 -112.43 2.9 260
SRA 1970 8 31 38.17 -112.33 2.9 259
SRA 1972 7 13 37.56 -111.94 2.9 215
SRA 1972 10 17 37.69 -112.93 2.9 303
SRA 1975 1 12 38 -112.91 2.9 305
SRA 1975 9 10 38.6 -112.59 2.9 297
SRA 1976 8 19 39.31 -111.11 2.9 245
SRA 1978 8 30 38.03 -112.49 2.9 269
SRA 1978 10 14 38.19 -112.35 2.9 262
SRA 1982 1 7 36.95 -112.88 2.9 305
SRA 1982 2 25 39.6 -109.4 2.9 233
SRA 1982 5 18 39.71 -110.73 2.9 267
SRA 1982 11 22 39.74 -107.58 2.9 299
SRA 1986 2 14 39.675 -110.525 2.9 257
SRA 1986 4 11 38.982 -106.94 2.9 277
PDE-Q 2009 11 27 38.96 -111.59 2.9 190
PDE-Q 2009 12 23 40.753 -112.056 2.9 258
PDE-Q 2010 1 5 40.36 -111.91 2.9 226
SRA 1962 3 16 36.88 -109.72 2.8 71
SRA 1965 2 26 39.84 -110.45 2.8 272
SRA 1965 6 17 39.51 -111.22 2.8 268
SRA 1965 10 22 38.99 -110.26 2.8 178
SRA 1966 2 17 36.98 -107.02 2.8 227
SRA 1966 2 27 36.9 -107 2.8 231
SRA 1966 5 5 37.03 -112.38 2.8 260
SRA 1966 5 30 38 -112.13 2.8 238
SRA 1966 6 21 36.9 -107.1 2.8 223
SRA 1967 11 16 39.55 -110.32 2.8 238
SRA 1968 2 23 37.6 -110.24 2.8 66
SRA 1968 9 20 38.49 -112.25 2.8 265
SRA 1970 1 22 39.58 -110.41 2.8 244
SRA 1970 12 3 35.874 -111.906 2.8 280
SRA 1971 2 24 39.49 -110.36 2.8 233
SRA 1973 2 10 38.06 -112.83 2.8 299
SRA 1974 9 16 38.7 -112.55 2.8 298
SRA 1975 9 29 35.96 -106.79 2.8 296
SRA 1975 10 6 39.15 -111.5 2.8 253
SRA 1976 6 30 38.85 -112.06 2.8 269
SRA 1976 7 9 38.97 -111.48 2.8 237
SRA 1976 11 6 39.47 -111.31 2.8 269
SRA 1977 3 25 39.76 -110.83 2.8 276
SRA 1980 3 1 39.62 -110.68 2.8 256
SRA 1981 6 9 39.51 -111.26 2.8 270
SRA 1982 2 15 39.2 -111.99 2.8 287
SRA 1982 12 9 39.31 -111.15 2.8 247
SRA 1983 12 15 37.575 -110.51 2.8 89
SRA 1985 6 11 39.166 -111.47 2.8 252
SRA 1985 9 6 39.594 -110.42 2.8 245
PDE-Q 2010 1 11 39.7 -111.26 2.8 152
SRA 1963 3 12 39.51 -110.66 2.7 244
SRA 1964 3 2 39.5 -111.87 2.7 303
SRA 1964 12 26 39.61 -110.38 2.7 246
SRA 1965 7 5 39.23 -111.44 2.7 256
SRA 1966 1 22 36.57 -111.99 2.7 244
SRA 1966 3 22 36.98 -107.02 2.7 227
SRA 1966 4 18 39.29 -112.07 2.7 299
SRA 1967 4 3 39.44 -111.07 2.7 255
SRA 1967 5 8 37.79 -110.17 2.7 67
SRA 1967 5 17 37.85 -112.3 2.7 249
SRA 1968 10 11 39.03 -110.17 2.7 179
SRA 1970 5 21 39.41 -110.31 2.7 223
SRA 1971 11 30 37.62 -113.09 2.7 317
SRA 1972 4 27 39.2 -111.45 2.7 254
SRA 1972 5 20 35.4 -107.36 2.7 301
SRA 1972 12 18 35.42 -107.16 2.7 311
SRA 1973 7 16 39.1 -111.43 2.7 244
SRA 1974 5 29 39.02 -111.48 2.7 241
SRA 1974 6 15 39.55 -110.58 2.7 246
SRA 1974 7 12 39.43 -112.13 2.7 313
SRA 1974 8 14 38.69 -112 2.7 255
SRA 1974 9 3 39.55 -111 2.7 262
SRA 1974 10 23 39.77 -110.75 2.7 274
SRA 1974 12 25 37.87 -112.99 2.7 310
SRA 1976 2 20 39.31 -111.14 2.7 246
SRA 1976 8 3 38.09 -112.45 2.7 267
SRA 1976 12 30 38.31 -112.2 2.7 253
SRA 1977 9 21 37.11 -111.54 2.7 185
SRA 1981 4 9 37.72 -110.54 2.7 94
SRA 1982 1 29 39.49 -112.18 2.7 321
SRA 1982 3 23 39.47 -112 2.7 308
SRA 1982 8 25 38.01 -111.64 2.7 196
SRA 1982 11 13 36.69 -106.71 2.7 263
SRA 1983 2 12 39.311 -111.162 2.7 247
SRA 1983 8 4 37.525 -110.452 2.7 84
SRA 1984 1 8 39.04 -111.509 2.7 245
SRA 1984 8 29 39.32 -111.162 2.7 248
SRA 1985 12 3 39.701 -111.171 2.7 284
SRA 1985 12 6 38.789 -108.899 2.7 152
SRA 1986 5 9 38.887 -106.884 2.7 275
SRA 1962 1 20 36.45 -110.4 2.6 141
SRA 1962 8 10 39.28 -111.42 2.6 259
SRA 1962 8 21 39.35 -111.03 2.6 244
SRA 1963 3 17 39.1 -111.96 2.6 278
SRA 1966 5 5 36.82 -112.39 2.6 267
SRA 1966 7 24 36.9 -107 2.6 231
SRA 1969 4 16 39.95 -110.72 2.6 291
SRA 1969 8 19 37.64 -110.65 2.6 102
SRA 1971 3 27 36.762 -112.393 2.6 269
SRA 1971 6 25 39.45 -110.34 2.6 228
SRA 1971 11 16 37.7 -113.1 2.6 318
SRA 1972 6 26 38.19 -112.47 2.6 272
SRA 1974 9 20 38.75 -112.33 2.6 284
SRA 1976 3 21 39.3 -111.2 2.6 248
SRA 1976 10 25 37.88 -112.7 2.6 285
SRA 1977 3 5 39.3 -111.28 2.6 253
SRA 1977 5 9 39.34 -111.1 2.6 247
SRA 1977 8 12 36.79 -110.92 2.6 148
SRA 1977 12 27 37.78 -112.52 2.6 268
SRA 1979 3 29 40.27 -108.81 2.6 313
SRA 1982 10 24 38.53 -112.28 2.6 269
SRA 1982 11 25 39.33 -111.12 2.6 247
SRA 1983 6 28 39.329 -111.133 2.6 247
SRA 1984 6 8 39.733 -110.94 2.6 277
SRA 1985 4 10 39.731 -110.936 2.6 277
SRA 1985 5 5 39.608 -110.375 2.6 245
SRA 1985 7 17 39.609 -110.397 2.6 246
SRA 1985 9 24 39.588 -110.42 2.6 245
SRA 1986 3 12 39.326 -111.094 2.6 245
SRA 1986 7 31 38.225 -112.556 2.6 280
SRA 1986 9 27 39.561 -110.403 2.6 241
SRA 1962 10 1 36.14 -111.74 2.5 250
SRA 1963 8 1 39.55 -110.33 2.5 238
SRA 1965 5 16 37.95 -112.45 2.5 264
SRA 1966 2 7 39.54 -111.09 2.5 265
SRA 1966 4 28 39.49 -110.33 2.5 232
SRA 1966 6 18 38.6 -112.7 2.5 306
SRA 1967 2 1 37.83 -110.17 2.5 69
SRA 1968 8 3 37.99 -112.39 2.5 260
SRA 1969 6 18 38.75 -112.21 2.5 275
SRA 1969 11 22 38.99 -111.49 2.5 240
SRA 1970 10 13 38.55 -112.26 2.5 268
SRA 1971 11 25 37.7 -113.1 2.5 318
SRA 1972 6 14 39.48 -109.93 2.5 222
SRA 1972 7 1 39.28 -110.25 2.5 208
SRA 1977 5 9 39.34 -111.1 2.6 247
SRA 1977 8 12 36.79 -110.92 2.6 148
SRA 1977 12 27 37.78 -112.52 2.6 268
SRA 1979 3 29 40.27 -108.81 2.6 313
SRA 1982 10 24 38.53 -112.28 2.6 269
SRA 1982 11 25 39.33 -111.12 2.6 247
SRA 1983 6 28 39.329 -111.133 2.6 247
SRA 1984 6 8 39.733 -110.94 2.6 277
SRA 1985 4 10 39.731 -110.936 2.6 277
SRA 1985 5 5 39.608 -110.375 2.6 245
SRA 1985 7 17 39.609 -110.397 2.6 246
SRA 1985 9 24 39.588 -110.42 2.6 245
SRA 1986 3 12 39.326 -111.094 2.6 245
SRA 1986 7 31 38.225 -112.556 2.6 280
SRA 1986 9 27 39.561 -110.403 2.6 241
SRA 1962 10 1 36.14 -111.74 2.5 250
SRA 1963 8 1 39.55 -110.33 2.5 238
SRA 1965 5 16 37.95 -112.45 2.5 264
SRA 1966 2 7 39.54 -111.09 2.5 265
SRA 1966 4 28 39.49 -110.33 2.5 232
SRA 1966 6 18 38.6 -112.7 2.5 306
SRA 1967 2 1 37.83 -110.17 2.5 69
SRA 1968 8 3 37.99 -112.39 2.5 260
SRA 1969 6 18 38.75 -112.21 2.5 275
SRA 1969 11 22 38.99 -111.49 2.5 240
SRA 1970 10 13 38.55 -112.26 2.5 268
SRA 1971 11 25 37.7 -113.1 2.5 318
SRA 1972 6 14 39.48 -109.93 2.5 222
SRA 1972 7 1 39.28 -110.25 2.5 208
SRA 1972 11 15 39 -111.43 2.5 237
SRA 1973 9 29 38.08 -113.07 2.5 320
SRA 1974 4 23 39.62 -110.28 2.5 244
SRA 1974 4 27 39.27 -110.98 2.5 235
SRA 1974 11 13 39.3 -110.24 2.5 209
SRA 1975 1 29 39.32 -111.11 2.5 246
SRA 1975 5 20 38.22 -112.78 2.5 299
SRA 1975 12 20 39.49 -110.65 2.5 242
SRA 1976 2 26 39.31 -111.06 2.5 242
SRA 1976 5 20 35.47 -109.04 2.5 228
SRA 1976 5 31 39.25 -111.19 2.5 243
SRA 1976 6 13 38.9 -111.97 2.5 266
SRA 1976 9 5 38.69 -112.42 2.5 288
SRA 1976 10 6 39.07 -111.63 2.5 255
SRA 1976 12 28 38.35 -111.17 2.5 174
SRA 1977 7 9 37.89 -112.4 2.5 259
SRA 1977 9 7 39.33 -111.12 2.5 247
SRA 1977 11 24 38.26 -112.3 2.5 260
SRA 1981 1 16 37.51 -113.11 2.5 319
SRA 1981 8 14 35.27 -107.9 2.5 285
SRA 1981 8 28 37.84 -112.93 2.5 304
SRA 1982 1 29 39.33 -111.12 2.5 247
SRA 1982 3 8 37.97 -112.16 2.5 240
SRA 1982 9 19 39.2 -111.94 2.5 284
SRA 1982 9 28 39.28 -111.15 2.5 244
SRA 1983 2 20 39.708 -110.95 2.5 275
SRA 1983 7 12 35.576 -107.11 2.5 302
SRA 1984 8 9 37.65 -112.471 2.5 262
SRA 1984 9 7 38.536 -112.287 2.5 270
SRA 1985 5 15 39.114 -111.455 2.5 247
SRA 1985 6 3 39.7 -110.72 2.5 266
SRA 1985 8 6 39.557 -110.397 2.5 241
SRA 1985 11 24 39.57 -110.477 2.5 244
SRA 1985 12 28 39.712 -110.596 2.5 263
SRA 1986 8 7 39.697 -110.736 2.5 266
SRA 1986 8 31 38.966 -111.419 2.5 233
SRA 1964 11 4 39.36 -110.29 2.4 217
SRA 1965 11 4 39.49 -111.04 2.4 258
SRA 1966 8 12 36.6 -107.2 2.4 227
SRA 1968 2 26 39.52 -111.05 2.4 261
SRA 1968 8 29 39.5 -110.38 2.4 234
SRA 1983 6 16 38.936 -111.391 2.4 229
SRA 1966 6 26 36.9 -107.2 2.3 214
SRA 1966 2 6 36.98 -107.02 2.2 227
SRA 1966 2 13 36.97 -106.96 2.2 232
SRA 1984 4 12 39.298 -107.232 2.2 281

APPENDIX 2: BOREHOLE LOG

APPENDIX 3: DEAGGREGATION OF SEISMIC HAZARD
FOR PGA FROM USGS NATIONAL SEISMIC HAZARDS
MAPPING PROJECT

*** Deaggregation of Seismic Hazard at One Period of Spectral Accel. ***

*** Data from U.S.G.S. National Seismic Hazards Mapping Project, 2008 version ***

PSHA Deaggregation. %contributions. site: White_Mesa long: 109.500 W., lat: 37.500
N.
Vs30(m/s)= 760.0 (some WUS atten. models use Site Class not Vs30).

NSHMP 2007-08 See USGS OFR 2008-1128. dM=0.2 below

Return period: 9900 yrs. Exceedance PGA =0.1511 g. Weight * Computed_Rate_Ex
0.101E-03
#Pr[at least one eq with median motion>=PGA in 50 yrs]=0.00192

#This deaggregation corresponds to Mean Hazard w/all GMPEs

DIST(KM) MAG(MW) ALL_EPS EPSILON>2 1<EPS<2 0<EPS<1
-1<EPS<0 -2<EPS<-1 EPS<-2
15.5 4.6 4.083 0.475 1.805 1.514 0.289 0 0
38.2 4.61 0.51 0.455 0.055 0 0 0 0
56.3 4.62 0.052 0.052 0 0 0 0 0
13.4 4.79 6.407 0.434 2.156 3.118 0.695 0.005 0
30.6 4.82 3.533 1.428 1.973 0.132 0 0 0
58.5 4.82 0.248 0.248 0 0 0 0 0
12 5.03 4.369 0.166 0.993 2.331 0.847 0.032 0
30.6 5.03 4.813 1.331 2.816 0.665 0 0 0
61 5.04 0.55 0.55 0 0 0 0 0
12.2 5.21 1.761 0.06 0.356 0.881 0.446 0.019 0
31.4 5.21 2.514 0.507 1.427 0.581 0 0 0
62 5.21 0.414 0.41 0.004 0 0 0 0
88.1 5.21 0.061 0.061 0 0 0 0 0
12.4 5.39 2.793 0.086 0.515 1.294 0.841 0.056 0
32.2 5.4 5.072 0.734 2.764 1.574 0 0 0
62.7 5.4 1.142 1.007 0.135 0 0 0 0
89.1 5.41 0.265 0.265 0 0 0 0 0
113.4 5.42 0.105 0.105 0 0 0 0 0
12.5 5.61 1.44 0.041 0.243 0.609 0.504 0.044 0
33.1 5.62 3.439 0.346 1.711 1.349 0.033 0 0
63.5 5.62 1.102 0.736 0.366 0 0 0 0
89.6 5.62 0.358 0.358 0 0 0 0 0
116.8 5.63 0.242 0.242 0 0 0 0 0
12.6 5.8 1.303 0.035 0.209 0.525 0.48 0.053 0
33.8 5.81 3.703 0.298 1.689 1.591 0.126 0 0
63.8 5.81 1.426 0.727 0.699 0 0 0 0
89.9 5.81 0.546 0.544 0.002 0 0 0 0
118.5 5.82 0.49 0.49 0 0 0 0 0
13.3 6.01 1.142 0.03 0.176 0.443 0.421 0.071 0.001
35 6.01 3.01 0.184 1.1 1.55 0.176 0 0
60.4 6.01 1.422 0.346 1.05 0.025 0 0 0
85.2 6.02 0.982 0.68 0.302 0 0 0 0
119.7 6.02 0.823 0.82 0.004 0 0 0 0
166.2 6.02 0.128 0.128 0 0 0 0 0
16.4 6.22 1.703 0.045 0.271 0.681 0.619 0.086 0.001
37.3 6.2 2.66 0.144 0.858 1.523 0.136 0 0
58.9 6.22 1.726 0.271 1.258 0.197 0 0 0
84.3 6.22 1.536 0.685 0.851 0 0 0 0
120.9 6.22 1.383 1.284 0.1 0 0 0 0
168.5 6.23 0.312 0.312 0 0 0 0 0
14.4 6.42 0.855 0.021 0.125 0.315 0.315 0.076 0.002
35.7 6.42 2.472 0.103 0.614 1.377 0.379 0 0
59.8 6.42 1.489 0.16 0.923 0.407 0 0 0
84.4 6.42 1.669 0.425 1.244 0 0 0 0
121.6 6.43 1.708 1.131 0.577 0 0 0 0
168.9 6.43 0.525 0.525 0 0 0 0 0
217.1 6.43 0.099 0.099 0 0 0 0 0
13.2 6.59 0.478 0.011 0.068 0.172 0.172 0.052 0.002
36.1 6.59 1.653 0.062 0.373 0.897 0.319 0.002 0
63.1 6.59 1.322 0.134 0.766 0.423 0 0 0
87.4 6.6 0.988 0.192 0.77 0.026 0 0 0
122.4 6.59 1.444 0.681 0.764 0 0 0 0
169.7 6.6 0.505 0.497 0.008 0 0 0 0
218.9 6.6 0.124 0.124 0 0 0 0 0
13.1 6.77 0.578 0.014 0.081 0.204 0.204 0.071 0.003
36.7 6.78 2.145 0.074 0.443 1.106 0.514 0.008 0
63 6.77 1.854 0.142 0.846 0.867 0 0 0
87.4 6.79 1.526 0.213 1.158 0.154 0 0 0
122.7 6.78 2.485 0.749 1.736 0 0 0 0
170.3 6.78 0.991 0.849 0.142 0 0 0 0
219.5 6.79 0.285 0.285 0 0 0 0 0
268.7 6.79 0.064 0.064 0 0 0 0 0
14.2 6.97 0.207 0.005 0.029 0.072 0.072 0.027 0.001
37.6 6.98 0.64 0.02 0.12 0.3 0.194 0.006 0
60.2 6.97 0.55 0.029 0.17 0.338 0.014 0 0
85.3 6.97 0.753 0.069 0.408 0.276 0 0 0
122.9 6.97 1.069 0.195 0.834 0.04 0 0 0
170.9 6.97 0.471 0.279 0.192 0 0 0 0
219.9 6.97 0.151 0.151 0 0 0 0 0
37.1 7.16 0.167 0.005 0.03 0.074 0.055 0.003 0
61.2 7.16 0.133 0.006 0.038 0.084 0.006 0 0
85 7.16 0.207 0.016 0.093 0.099 0 0 0
123.3 7.16 0.307 0.042 0.225 0.04 0 0 0
171.1 7.16 0.16 0.065 0.095 0 0 0 0
220.5 7.16 0.054 0.052 0.002 0 0 0 0

Summary statistics for above PSHA PGA deaggregation, R=distance, e=epsilon:

Contribution from this GMPE(%): 100.0

Mean src-site R= 51.5 km; M= 5.81; eps0= 0.34. Mean calculated for all sources.

Modal src-site R= 13.4 km; M= 4.79; eps0= -0.26 from peak (R,M) bin

MODE R*= 12.2km; M*= 4.80; EPS.INTERVAL: 0 to 1 sigma % CONTRIB.= 3.118

Principal sources (faults, subduction, random seismicity having > 3% contribution)

Source Category: % contr. R(km) M epsilon0 (mean values).

CEUS gridded 100.00 51.5 5.81 0.34

Individual fault hazard details if its contribution to mean hazard > 2%:

Fault ID % contr. Rcd(km) M epsilon0 Site-to-src azimuth(d)

#*********End of deaggregation corresponding to Mean Hazard w/all GMPEs
*********#

PSHA Deaggregation. %contributions. site: White_Mesa long: 109.500 W., lat: 37.500
N.
Vs30(m/s)= 760.0 (some WUS atten. models use Site Class not Vs30).

NSHMP 2007-08 See USGS OFR 2008-1128. dM=0.2 below

Return period: 9900 yrs. Exceedance PGA =0.1511 g. Weight * Computed_Rate_Ex
0.277E-04
#Pr[at least one eq with median motion>=PGA in 50 yrs]=0.00207

#This deaggregation corresponds to Toro et al. 1997

DIST(KM) MAG(MW) ALL_EPS EPSILON>2 1<EPS<2 0<EPS<1
-1<EPS<0 -2<EPS<-1 EPS<-2
11.7 4.6 0.766 0.156 0.585 0.024 0 0 0
30.1 4.61 0.591 0.51 0.081 0 0 0 0
56.9 4.62 0.035 0.035 0 0 0 0 0
11.8 4.8 1.378 0.258 1.059 0.062 0 0 0
30.6 4.81 1.276 0.999 0.277 0 0 0 0
59.4 4.82 0.126 0.126 0 0 0 0 0
12.1 5.03 1.081 0.166 0.834 0.081 0 0 0
31.6 5.03 1.421 0.921 0.5 0 0 0 0
61.5 5.04 0.255 0.255 0 0 0 0 0
86.1 5.06 0.017 0.017 0 0 0 0 0
12.3 5.21 0.438 0.06 0.331 0.047 0 0 0
32.4 5.21 0.737 0.411 0.326 0 0 0 0
62.5 5.21 0.184 0.184 0 0 0 0 0
87.6 5.21 0.025 0.025 0 0 0 0 0
12.4 5.39 0.697 0.086 0.502 0.109 0 0 0
33.1 5.4 1.466 0.68 0.786 0 0 0 0
63.1 5.4 0.482 0.482 0.001 0 0 0 0
88.7 5.4 0.105 0.105 0 0 0 0 0
108.7 5.41 0.021 0.021 0 0 0 0 0
12.6 5.61 0.365 0.041 0.242 0.082 0 0 0
34.1 5.62 1.027 0.346 0.679 0.002 0 0 0
63.9 5.62 0.477 0.445 0.031 0 0 0 0
89.3 5.63 0.148 0.148 0 0 0 0 0
114.1 5.64 0.071 0.071 0 0 0 0 0
12.6 5.8 0.324 0.035 0.209 0.079 0 0 0
34.4 5.81 0.993 0.298 0.689 0.006 0 0 0
64.1 5.81 0.507 0.454 0.053 0 0 0 0
89.4 5.81 0.17 0.17 0 0 0 0 0
115.3 5.82 0.096 0.096 0 0 0 0 0
13.3 6.01 0.289 0.03 0.176 0.083 0 0 0
35.6 6.01 0.86 0.184 0.657 0.019 0 0 0
61.2 6.01 0.544 0.333 0.211 0 0 0 0
84.9 6.02 0.359 0.344 0.015 0 0 0 0
118.1 6.02 0.22 0.22 0 0 0 0 0
161.8 6.03 0.02 0.02 0 0 0 0 0
16.5 6.22 0.432 0.045 0.271 0.115 0 0 0
37.5 6.2 0.695 0.144 0.545 0.007 0 0 0
59.2 6.21 0.545 0.271 0.274 0 0 0 0
83.5 6.22 0.465 0.425 0.04 0 0 0 0
118.7 6.22 0.265 0.265 0 0 0 0 0
164.7 6.22 0.032 0.032 0 0 0 0 0
14.4 6.42 0.217 0.021 0.125 0.071 0 0 0
35.9 6.42 0.68 0.103 0.522 0.056 0 0 0
61.9 6.42 0.571 0.212 0.359 0 0 0 0
85.1 6.42 0.491 0.331 0.16 0 0 0 0
120.1 6.42 0.403 0.401 0.002 0 0 0 0
167.8 6.43 0.098 0.098 0 0 0 0 0
13.3 6.59 0.12 0.011 0.068 0.04 0 0 0
36.3 6.59 0.437 0.062 0.33 0.044 0 0 0
63.1 6.59 0.392 0.134 0.258 0 0 0 0
86.4 6.61 0.295 0.179 0.116 0 0 0 0
120.7 6.6 0.284 0.273 0.011 0 0 0 0
168.9 6.61 0.078 0.078 0 0 0 0 0
13.2 6.77 0.145 0.014 0.081 0.05 0 0 0
36.7 6.78 0.559 0.074 0.414 0.071 0 0 0
63.4 6.77 0.534 0.142 0.392 0 0 0 0
87 6.79 0.388 0.212 0.176 0 0 0 0
120.8 6.78 0.435 0.402 0.033 0 0 0 0
169.4 6.78 0.134 0.134 0 0 0 0 0
215.8 6.79 0.023 0.023 0 0 0 0 0
14.2 6.97 0.052 0.005 0.029 0.019 0 0 0
37.8 6.97 0.175 0.02 0.119 0.036 0 0 0
60.4 6.96 0.169 0.029 0.139 0.002 0 0 0
84.7 6.97 0.226 0.068 0.157 0 0 0 0
121.7 6.97 0.237 0.171 0.066 0 0 0 0
170.8 6.96 0.092 0.092 0 0 0 0 0
218.6 6.96 0.025 0.025 0 0 0 0 0
37.1 7.16 0.043 0.005 0.03 0.008 0 0 0
61.2 7.16 0.034 0.006 0.028 0 0 0 0
84.1 7.16 0.046 0.016 0.031 0 0 0 0
121.1 7.16 0.043 0.035 0.008 0 0 0 0
170 7.16 0.016 0.016 0 0 0 0 0

Summary statistics for above PSHA PGA deaggregation, R=distance, e=epsilon:

Contribution from this GMPE(%): 27.5

Mean src-site R= 48.4 km; M= 5.77; eps0= 0.56. Mean calculated for all sources.

Modal src-site R= 33.1 km; M= 5.40; eps0= 0.69 from peak (R,M) bin

MODE R*= 11.9km; M*= 4.80; EPS.INTERVAL: 0 to 1 sigma % CONTRIB.= 1.059

Principal sources (faults, subduction, random seismicity having > 3% contribution)

Source Category: % contr. R(km) M epsilon0 (mean values).

CEUS gridded 27.49 48.4 5.77 0.56

Individual fault hazard details if its contribution to mean hazard > 2%:

Fault ID % contr. Rcd(km) M epsilon0 Site-to-src azimuth(d)

#*********End of deaggregation corresponding to Toro et al. 1997 *********#

PSHA Deaggregation. %contributions. site: White_Mesa long: 109.500 W., lat: 37.500
N.
Vs30(m/s)= 760.0 (some WUS atten. models use Site Class not Vs30).

NSHMP 2007-08 See USGS OFR 2008-1128. dM=0.2 below

Return period: 9900 yrs. Exceedance PGA =0.1511 g. Weight * Computed_Rate_Ex
0.253E-05
#Pr[at least one eq with median motion>=PGA in 50 yrs]=0.00058

#This deaggregation corresponds to Atkinson-Boore06,140 bar

DIST(KM) MAG(MW) ALL_EPS EPSILON>2 1<EPS<2 0<EPS<1
-1<EPS<0 -2<EPS<-1 EPS<-2
8.6 4.61 0.102 0.064 0.038 0 0 0 0
9.5 4.8 0.254 0.147 0.106 0 0 0 0
10.7 5.03 0.255 0.146 0.108 0 0 0 0
11.7 5.21 0.125 0.064 0.061 0 0 0 0
12.9 5.4 0.24 0.115 0.124 0 0 0 0
34 5.42 0.003 0.003 0 0 0 0 0
14.2 5.62 0.154 0.072 0.081 0 0 0 0
35.5 5.63 0.006 0.006 0 0 0 0 0
15.4 5.8 0.168 0.08 0.088 0 0 0 0
37 5.82 0.013 0.013 0 0 0 0 0
13.7 6.01 0.123 0.04 0.084 0 0 0 0
31.1 6.03 0.047 0.043 0.004 0 0 0 0
54.3 6.03 0.002 0.002 0 0 0 0 0
15 6.22 0.155 0.045 0.11 0 0 0 0
33.8 6.2 0.058 0.054 0.003 0 0 0 0
55.9 6.23 0.007 0.007 0 0 0 0 0
17.6 6.42 0.138 0.044 0.094 0 0 0 0
38.5 6.42 0.039 0.038 0 0 0 0 0
57.7 6.43 0.01 0.01 0 0 0 0 0
85.7 6.44 0.006 0.006 0 0 0 0 0
123.5 6.44 0.011 0.011 0 0 0 0 0
12.8 6.59 0.054 0.011 0.043 0 0 0 0
31.9 6.59 0.068 0.045 0.023 0 0 0 0
58.6 6.59 0.01 0.01 0 0 0 0 0
85.9 6.59 0.009 0.009 0 0 0 0 0
124.7 6.57 0.011 0.011 0 0 0 0 0
125.5 6.63 0.007 0.007 0 0 0 0 0
159.7 6.6 0.003 0.003 0 0 0 0 0
12.9 6.77 0.067 0.014 0.054 0 0 0 0
32.9 6.78 0.104 0.062 0.042 0 0 0 0
60.5 6.78 0.023 0.023 0 0 0 0 0
87.9 6.8 0.017 0.017 0 0 0 0 0
125.3 6.79 0.045 0.045 0 0 0 0 0
166.6 6.8 0.016 0.016 0 0 0 0 0
15.9 6.98 0.029 0.006 0.023 0 0 0 0
36.1 6.97 0.029 0.018 0.012 0 0 0 0
58.8 6.97 0.01 0.01 0 0 0 0 0
86.2 6.98 0.01 0.01 0 0 0 0 0
124.7 7.03 0.011 0.011 0 0 0 0 0
125.8 6.92 0.012 0.012 0 0 0 0 0
169.3 6.98 0.011 0.011 0 0 0 0 0
212.8 6.99 0.001 0.001 0 0 0 0 0
13.8 7.16 0.005 0.001 0.004 0 0 0 0
34.3 7.16 0.011 0.005 0.006 0 0 0 0
60.1 7.16 0.003 0.003 0 0 0 0 0
85.8 7.16 0.004 0.004 0 0 0 0 0
125.4 7.16 0.009 0.009 0 0 0 0 0
170.3 7.16 0.005 0.005 0 0 0 0 0

Summary statistics for above PSHA PGA deaggregation, R=distance, e=epsilon:

Contribution from this GMPE(%): 2.5

Mean src-site R= 25.8 km; M= 5.83; eps0= 0.24. Mean calculated for all sources.

Modal src-site R= 10.7 km; M= 5.03; eps0= 0.25 from peak (R,M) bin

MODE R*= 11.0km; M*= 4.80; EPS.INTERVAL: 0 to 1 sigma % CONTRIB.= 0.147

Principal sources (faults, subduction, random seismicity having > 3% contribution)

Source Category: % contr. R(km) M epsilon0 (mean values).

Individual fault hazard details if its contribution to mean hazard > 2%:

Fault ID % contr. Rcd(km) M epsilon0 Site-to-src azimuth(d)
#*********End of deaggregation corresponding to Atkinson-Boore06,140 bar
*********#

PSHA Deaggregation. %contributions. site: White_Mesa long: 109.500 W. lat:
37.500 N.
Vs30(m/s)= 760.0 (some WUS atten. models use Site Class not Vs30).
NSHMP 2007-08 See USGS OFR 2008-1128. dM=0.2 below
Return period: 9900 yrs. Exceedance PGA =0.1511 g. Weight * Computed_Rate_Ex
0.227E-04
#Pr[at least one eq with median motion>=PGA in 50 yrs]=0.00331
#This deaggregation corresponds to Frankel et al. 1996
DIST(KM) MAG(MW) ALL_EPS EPSILON>2 1<EPS<2 0<EPS<1 -1<EPS<0 -
2<EPS<-1 EPS<-2
14.7 4.59 0.589 0.275 0.314 0.000 0.000 0.000 0.000
31.0 4.64 0.226 0.218 0.009 0.000 0.000 0.000 0.000
12.2 4.80 0.912 0.258 0.654 0.000 0.000 0.000 0.000
30.1 4.80 0.951 0.836 0.115 0.000 0.000 0.000 0.000
57.6 4.82 0.053 0.053 0.000 0.000 0.000 0.000 0.000
12.4 5.03 0.683 0.166 0.517 0.000 0.000 0.000 0.000
31.3 5.03 1.026 0.781 0.246 0.000 0.000 0.000 0.000
61.1 5.04 0.136 0.136 0.000 0.000 0.000 0.000 0.000
87.4 5.08 0.012 0.012 0.000 0.000 0.000 0.000 0.000
12.6 5.21 0.266 0.060 0.206 0.000 0.000 0.000 0.000
32.2 5.21 0.522 0.353 0.170 0.000 0.000 0.000 0.000
62.4 5.21 0.106 0.106 0.000 0.000 0.000 0.000 0.000
89.3 5.21 0.024 0.024 0.000 0.000 0.000 0.000 0.000
12.7 5.39 0.410 0.086 0.323 0.000 0.000 0.000 0.000
33.1 5.40 1.027 0.623 0.404 0.000 0.000 0.000 0.000
63.2 5.41 0.295 0.295 0.000 0.000 0.000 0.000 0.000
89.9 5.41 0.100 0.100 0.000 0.000 0.000 0.000 0.000
115.4 5.42 0.076 0.076 0.000 0.000 0.000 0.000 0.000
12.7 5.61 0.203 0.041 0.163 0.000 0.000 0.000 0.000
34.1 5.62 0.649 0.339 0.310 0.000 0.000 0.000 0.000
64.0 5.62 0.270 0.270 0.000 0.000 0.000 0.000 0.000
90.1 5.62 0.120 0.120 0.000 0.000 0.000 0.000 0.000
119.5 5.62 0.138 0.138 0.000 0.000 0.000 0.000 0.000
12.8 5.80 0.181 0.035 0.146 0.000 0.000 0.000 0.000
34.9 5.80 0.696 0.298 0.398 0.000 0.000 0.000 0.000
64.5 5.81 0.380 0.375 0.005 0.000 0.000 0.000 0.000
90.3 5.81 0.200 0.200 0.000 0.000 0.000 0.000 0.000
120.9 5.81 0.273 0.273 0.000 0.000 0.000 0.000 0.000
162.5 5.83 0.047 0.047 0.000 0.000 0.000 0.000 0.000
13.5 6.01 0.155 0.030 0.125 0.000 0.000 0.000 0.000
35.8 6.01 0.525 0.184 0.341 0.000 0.000 0.000 0.000
60.8 6.01 0.324 0.282 0.041 0.000 0.000 0.000 0.000
85.9 6.02 0.298 0.298 0.000 0.000 0.000 0.000 0.000
121.5 6.01 0.369 0.369 0.000 0.000 0.000 0.000 0.000
167.8 6.02 0.096 0.096 0.000 0.000 0.000 0.000 0.000
16.7 6.23 0.235 0.045 0.189 0.000 0.000 0.000 0.000
37.8 6.20 0.464 0.144 0.320 0.000 0.000 0.000 0.000
59.3 6.21 0.390 0.269 0.121 0.000 0.000 0.000 0.000
85.1 6.22 0.465 0.463 0.001 0.000 0.000 0.000 0.000
122.5 6.22 0.605 0.605 0.000 0.000 0.000 0.000 0.000
169.9 6.22 0.217 0.217 0.000 0.000 0.000 0.000 0.000
214.9 6.24 0.036 0.036 0.000 0.000 0.000 0.000 0.000
14.5 6.42 0.113 0.021 0.092 0.000 0.000 0.000 0.000
36.2 6.42 0.392 0.103 0.290 0.000 0.000 0.000 0.000
60.2 6.42 0.300 0.159 0.141 0.000 0.000 0.000 0.000
85.1 6.42 0.432 0.397 0.034 0.000 0.000 0.000 0.000
123.1 6.42 0.621 0.621 0.000 0.000 0.000 0.000 0.000
170.3 6.43 0.285 0.285 0.000 0.000 0.000 0.000 0.000
218.2 6.43 0.074 0.074 0.000 0.000 0.000 0.000 0.000
13.4 6.59 0.062 0.011 0.051 0.000 0.000 0.000 0.000
36.7 6.59 0.258 0.062 0.196 0.000 0.000 0.000 0.000
64.1 6.59 0.275 0.134 0.141 0.000 0.000 0.000 0.000
88.1 6.60 0.249 0.191 0.057 0.000 0.000 0.000 0.000
123.8 6.59 0.495 0.491 0.004 0.000 0.000 0.000 0.000
171.1 6.59 0.256 0.256 0.000 0.000 0.000 0.000 0.000
219.5 6.59 0.084 0.084 0.000 0.000 0.000 0.000 0.000
266.9 6.60 0.016 0.016 0.000 0.000 0.000 0.000 0.000
13.2 6.77 0.074 0.014 0.061 0.000 0.000 0.000 0.000
37.2 6.77 0.327 0.074 0.253 0.000 0.000 0.000 0.000
63.7 6.77 0.359 0.142 0.218 0.000 0.000 0.000 0.000
87.8 6.79 0.367 0.213 0.155 0.000 0.000 0.000 0.000
124.0 6.78 0.770 0.678 0.092 0.000 0.000 0.000 0.000
171.7 6.78 0.451 0.451 0.000 0.000 0.000 0.000 0.000
220.2 6.79 0.173 0.173 0.000 0.000 0.000 0.000 0.000
268.9 6.79 0.044 0.044 0.000 0.000 0.000 0.000 0.000
14.2 6.97 0.026 0.005 0.022 0.000 0.000 0.000 0.000
37.9 6.98 0.093 0.020 0.073 0.000 0.000 0.000 0.000
60.5 6.97 0.092 0.029 0.064 0.000 0.000 0.000 0.000
85.7 6.97 0.154 0.068 0.085 0.000 0.000 0.000 0.000
124.2 6.97 0.276 0.194 0.082 0.000 0.000 0.000 0.000
172.3 6.97 0.176 0.175 0.001 0.000 0.000 0.000 0.000
220.7 6.97 0.074 0.074 0.000 0.000 0.000 0.000 0.000
270.2 6.98 0.022 0.022 0.000 0.000 0.000 0.000 0.000
37.6 7.16 0.024 0.005 0.019 0.000 0.000 0.000 0.000
61.5 7.16 0.023 0.006 0.017 0.000 0.000 0.000 0.000
85.4 7.16 0.042 0.016 0.027 0.000 0.000 0.000 0.000
124.5 7.16 0.078 0.042 0.036 0.000 0.000 0.000 0.000
172.7 7.16 0.059 0.056 0.004 0.000 0.000 0.000 0.000
221.2 7.16 0.027 0.027 0.000 0.000 0.000 0.000 0.000

Summary statistics for above PSHA PGA deaggregation, R=distance, e=epsilon:
Contribution from this GMPE(%): 22.5
Mean src-site R= 69.4 km; M= 5.90; eps0= 0.56. Mean calculated for all sources.
Modal src-site R= 33.1 km; M= 5.40; eps0= 0.42 from peak (R,M) bin
MODE R*= 30.7km; M*= 4.80; EPS.INTERVAL: 0 to 1 sigma % CONTRIB.= 0.836

Principal sources (faults, subduction, random seismicity having > 3% contribution)
Source Category: % contr. R(km) M epsilon0 (mean values).
CEUS gridded 22.46 69.4 5.90 0.56
Individual fault hazard details if its contribution to mean hazard > 2%:
Fault ID % contr. Rcd(km) M epsilon0 Site-to-src azimuth(d)
#*********End of deaggregation corresponding to Frankel et al., 1996 *********#

PSHA Deaggregation. %contributions. site: White_Mesa long: 109.500 W., lat: 37.500
N.
Vs30(m/s)= 760.0 (some WUS atten. models use Site Class not Vs30).
NSHMP 2007-08 See USGS OFR 2008-1128. dM=0.2 below
Return period: 9900 yrs. Exceedance PGA =0.1511 g. Weight * Computed_Rate_Ex
0.146E-04
#Pr[at least one eq with median motion>=PGA in 50 yrs]=0.00385
#This deaggregation corresponds to Campbell CEUS Hybrid
DIST(KM) MAG(MW) ALL_EPS EPSILON>2 1<EPS<2 0<EPS<1 -1<EPS<0 -
2<EPS<-1 EPS<-2
16.1 4.60 0.902 0.406 0.496 0.000 0.000 0.000 0.000
37.0 4.61 0.085 0.085 0.000 0.000 0.000 0.000 0.000
17.1 4.80 1.808 0.755 1.053 0.000 0.000 0.000 0.000
37.5 4.80 0.252 0.252 0.000 0.000 0.000 0.000 0.000
54.0 4.82 0.010 0.010 0.000 0.000 0.000 0.000 0.000
12.5 5.03 0.795 0.166 0.629 0.000 0.000 0.000 0.000
29.3 5.03 0.959 0.648 0.311 0.000 0.000 0.000 0.000
55.7 5.04 0.025 0.025 0.000 0.000 0.000 0.000 0.000
12.7 5.21 0.300 0.060 0.241 0.000 0.000 0.000 0.000
30.0 5.21 0.476 0.287 0.190 0.000 0.000 0.000 0.000
56.9 5.21 0.021 0.021 0.000 0.000 0.000 0.000 0.000
12.8 5.39 0.450 0.086 0.364 0.000 0.000 0.000 0.000
30.9 5.40 0.923 0.502 0.421 0.000 0.000 0.000 0.000
59.1 5.41 0.067 0.067 0.000 0.000 0.000 0.000 0.000
12.9 5.61 0.218 0.041 0.177 0.000 0.000 0.000 0.000
32.0 5.62 0.595 0.288 0.307 0.000 0.000 0.000 0.000
60.4 5.62 0.070 0.070 0.000 0.000 0.000 0.000 0.000
89.3 5.63 0.012 0.012 0.000 0.000 0.000 0.000 0.000
12.9 5.80 0.190 0.035 0.155 0.000 0.000 0.000 0.000
33.0 5.80 0.652 0.283 0.368 0.000 0.000 0.000 0.000
61.2 5.81 0.113 0.113 0.000 0.000 0.000 0.000 0.000
89.9 5.82 0.029 0.029 0.000 0.000 0.000 0.000 0.000
113.7 5.83 0.020 0.020 0.000 0.000 0.000 0.000 0.000
13.6 6.01 0.161 0.030 0.132 0.000 0.000 0.000 0.000
34.5 6.01 0.511 0.184 0.327 0.000 0.000 0.000 0.000
58.4 6.01 0.132 0.132 0.000 0.000 0.000 0.000 0.000
85.2 6.02 0.057 0.057 0.000 0.000 0.000 0.000 0.000
116.8 6.02 0.043 0.043 0.000 0.000 0.000 0.000 0.000
16.9 6.23 0.246 0.045 0.201 0.000 0.000 0.000 0.000
37.1 6.20 0.465 0.144 0.321 0.000 0.000 0.000 0.000
57.7 6.22 0.200 0.179 0.021 0.000 0.000 0.000 0.000
84.4 6.22 0.115 0.115 0.000 0.000 0.000 0.000 0.000
119.1 6.22 0.098 0.098 0.000 0.000 0.000 0.000 0.000
14.6 6.42 0.115 0.021 0.094 0.000 0.000 0.000 0.000
35.8 6.42 0.411 0.103 0.308 0.000 0.000 0.000 0.000
58.8 6.42 0.178 0.134 0.044 0.000 0.000 0.000 0.000
84.5 6.43 0.139 0.139 0.000 0.000 0.000 0.000 0.000
120.1 6.43 0.134 0.134 0.000 0.000 0.000 0.000 0.000
158.3 6.44 0.010 0.010 0.000 0.000 0.000 0.000 0.000
13.4 6.59 0.063 0.011 0.051 0.000 0.000 0.000 0.000
36.4 6.59 0.275 0.062 0.213 0.000 0.000 0.000 0.000
62.0 6.59 0.168 0.115 0.053 0.000 0.000 0.000 0.000
87.6 6.60 0.097 0.097 0.000 0.000 0.000 0.000 0.000
120.9 6.59 0.133 0.133 0.000 0.000 0.000 0.000 0.000
161.1 6.59 0.015 0.015 0.000 0.000 0.000 0.000 0.000
13.2 6.77 0.075 0.014 0.061 0.000 0.000 0.000 0.000
37.2 6.78 0.352 0.074 0.278 0.000 0.000 0.000 0.000
61.8 6.77 0.257 0.140 0.117 0.000 0.000 0.000 0.000
87.3 6.79 0.179 0.171 0.008 0.000 0.000 0.000 0.000
121.3 6.79 0.268 0.268 0.000 0.000 0.000 0.000 0.000
164.2 6.79 0.042 0.042 0.000 0.000 0.000 0.000 0.000
14.3 6.97 0.027 0.005 0.022 0.000 0.000 0.000 0.000
38.1 6.98 0.102 0.020 0.082 0.000 0.000 0.000 0.000
59.7 6.97 0.081 0.029 0.053 0.000 0.000 0.000 0.000
85.3 6.98 0.092 0.068 0.024 0.000 0.000 0.000 0.000
121.7 6.98 0.123 0.121 0.002 0.000 0.000 0.000 0.000
166.0 6.98 0.024 0.024 0.000 0.000 0.000 0.000 0.000
37.8 7.16 0.026 0.005 0.021 0.000 0.000 0.000 0.000
60.9 7.16 0.022 0.006 0.016 0.000 0.000 0.000 0.000
85.1 7.16 0.031 0.016 0.015 0.000 0.000 0.000 0.000
122.3 7.16 0.044 0.037 0.007 0.000 0.000 0.000 0.000
166.7 7.16 0.012 0.012 0.000 0.000 0.000 0.000 0.000

Summary statistics for above PSHA PGA deaggregation, R=distance, e=epsilon:
Contribution from this GMPE(%): 14.5
Mean src-site R= 37.9 km; M= 5.66; eps0= -0.22. Mean calculated for all sources.
Modal src-site R= 17.1 km; M= 4.80; eps0= -0.45 from peak (R,M) bin
MODE R*= 14.5km; M*= 4.80; EPS.INTERVAL: 0 to 1 sigma % CONTRIB.= 1.053

Principal sources (faults, subduction, random seismicity having > 3% contribution)
Source Category: % contr. R(km) M epsilon0 (mean values).
CEUS gridded 14.51 37.9 5.66 -0.22
Individual fault hazard details if its contribution to mean hazard > 2%:
Fault ID % contr. Rcd(km) M epsilon0 Site-to-src azimuth(d)
#*********End of deaggregation corresponding to Campbell CEUS Hybrid
*********#

PSHA Deaggregation. %contributions. site: White_Mesa long: 109.500 W., lat: 37.500
N.
Vs30(m/s)= 760.0 (some WUS atten. models use Site Class not Vs30).
NSHMP 2007-08 See USGS OFR 2008-1128. dM=0.2 below
Return period: 9900 yrs. Exceedance PGA =0.1511 g. Weight * Computed_Rate_Ex
0.153E-04
#Pr[at least one eq with median motion>=PGA in 50 yrs]=0.00185
#This deaggregation corresponds to Silva 1-corner
DIST(KM) MAG(MW) ALL_EPS EPSILON>2 1<EPS<2 0<EPS<1 -1<EPS<0 -
2<EPS<-1 EPS<-2
11.6 4.60 0.317 0.156 0.160 0.000 0.000 0.000 0.000
29.9 4.61 0.248 0.248 0.000 0.000 0.000 0.000 0.000
55.5 4.62 0.009 0.009 0.000 0.000 0.000 0.000 0.000
11.8 4.80 0.633 0.258 0.376 0.000 0.000 0.000 0.000
30.8 4.80 0.668 0.662 0.007 0.000 0.000 0.000 0.000
58.2 4.81 0.059 0.059 0.000 0.000 0.000 0.000 0.000
12.1 5.03 0.496 0.166 0.329 0.000 0.000 0.000 0.000
31.9 5.03 0.723 0.658 0.065 0.000 0.000 0.000 0.000
61.2 5.04 0.129 0.129 0.000 0.000 0.000 0.000 0.000
12.2 5.21 0.201 0.060 0.142 0.000 0.000 0.000 0.000
32.7 5.21 0.370 0.307 0.063 0.000 0.000 0.000 0.000
62.3 5.21 0.096 0.096 0.000 0.000 0.000 0.000 0.000
86.5 5.21 0.011 0.011 0.000 0.000 0.000 0.000 0.000
12.4 5.39 0.323 0.086 0.236 0.000 0.000 0.000 0.000
33.5 5.40 0.731 0.550 0.181 0.000 0.000 0.000 0.000
63.1 5.40 0.259 0.259 0.000 0.000 0.000 0.000 0.000
88.6 5.41 0.055 0.055 0.000 0.000 0.000 0.000 0.000
12.5 5.61 0.168 0.041 0.127 0.000 0.000 0.000 0.000
34.3 5.62 0.478 0.315 0.162 0.000 0.000 0.000 0.000
63.9 5.62 0.230 0.230 0.000 0.000 0.000 0.000 0.000
89.3 5.62 0.070 0.070 0.000 0.000 0.000 0.000 0.000
111.3 5.63 0.027 0.027 0.000 0.000 0.000 0.000 0.000
12.6 5.80 0.155 0.035 0.120 0.000 0.000 0.000 0.000
34.9 5.80 0.525 0.296 0.229 0.000 0.000 0.000 0.000
64.4 5.81 0.320 0.320 0.000 0.000 0.000 0.000 0.000
89.6 5.81 0.120 0.120 0.000 0.000 0.000 0.000 0.000
116.1 5.82 0.078 0.078 0.000 0.000 0.000 0.000 0.000
13.3 6.01 0.136 0.030 0.107 0.000 0.000 0.000 0.000
35.8 6.01 0.407 0.184 0.223 0.000 0.000 0.000 0.000
60.8 6.01 0.273 0.258 0.015 0.000 0.000 0.000 0.000
84.7 6.02 0.203 0.203 0.000 0.000 0.000 0.000 0.000
118.4 6.02 0.129 0.129 0.000 0.000 0.000 0.000 0.000
160.4 6.03 0.011 0.011 0.000 0.000 0.000 0.000 0.000
16.5 6.23 0.207 0.045 0.162 0.000 0.000 0.000 0.000
37.8 6.20 0.369 0.144 0.225 0.000 0.000 0.000 0.000
59.5 6.21 0.334 0.262 0.072 0.000 0.000 0.000 0.000
83.9 6.22 0.336 0.336 0.000 0.000 0.000 0.000 0.000
119.9 6.22 0.241 0.241 0.000 0.000 0.000 0.000 0.000
167.5 6.23 0.051 0.051 0.000 0.000 0.000 0.000 0.000
14.4 6.42 0.104 0.021 0.083 0.000 0.000 0.000 0.000
36.1 6.42 0.326 0.103 0.223 0.000 0.000 0.000 0.000
60.3 6.42 0.262 0.159 0.102 0.000 0.000 0.000 0.000
84.2 6.42 0.328 0.318 0.009 0.000 0.000 0.000 0.000
120.9 6.43 0.279 0.279 0.000 0.000 0.000 0.000 0.000
169.6 6.43 0.093 0.093 0.000 0.000 0.000 0.000 0.000
215.1 6.44 0.017 0.017 0.000 0.000 0.000 0.000 0.000
13.2 6.59 0.059 0.011 0.047 0.000 0.000 0.000 0.000
36.5 6.59 0.220 0.062 0.157 0.000 0.000 0.000 0.000
64.1 6.59 0.242 0.134 0.108 0.000 0.000 0.000 0.000
87.5 6.60 0.188 0.172 0.016 0.000 0.000 0.000 0.000
121.8 6.59 0.244 0.244 0.000 0.000 0.000 0.000 0.000
170.9 6.59 0.097 0.097 0.000 0.000 0.000 0.000 0.000
218.8 6.59 0.029 0.029 0.000 0.000 0.000 0.000 0.000
13.1 6.77 0.071 0.014 0.057 0.000 0.000 0.000 0.000
37.1 6.78 0.285 0.074 0.211 0.000 0.000 0.000 0.000
63.7 6.77 0.319 0.142 0.177 0.000 0.000 0.000 0.000
87.3 6.79 0.288 0.212 0.076 0.000 0.000 0.000 0.000
122.4 6.78 0.419 0.417 0.002 0.000 0.000 0.000 0.000
171.5 6.79 0.199 0.199 0.000 0.000 0.000 0.000 0.000
220.2 6.79 0.075 0.075 0.000 0.000 0.000 0.000 0.000
268.9 6.80 0.019 0.019 0.000 0.000 0.000 0.000 0.000
14.2 6.97 0.025 0.005 0.021 0.000 0.000 0.000 0.000
37.8 6.98 0.083 0.020 0.063 0.000 0.000 0.000 0.000
60.5 6.97 0.083 0.029 0.055 0.000 0.000 0.000 0.000
85.1 6.97 0.125 0.068 0.057 0.000 0.000 0.000 0.000
122.8 6.97 0.163 0.153 0.011 0.000 0.000 0.000 0.000
172.2 6.97 0.089 0.089 0.000 0.000 0.000 0.000 0.000
221.0 6.98 0.038 0.038 0.000 0.000 0.000 0.000 0.000
270.8 6.98 0.013 0.013 0.000 0.000 0.000 0.000 0.000
37.4 7.16 0.022 0.005 0.017 0.000 0.000 0.000 0.000
61.5 7.16 0.021 0.006 0.015 0.000 0.000 0.000 0.000
84.9 7.16 0.036 0.016 0.020 0.000 0.000 0.000 0.000
123.3 7.16 0.050 0.040 0.009 0.000 0.000 0.000 0.000
172.6 7.16 0.033 0.033 0.000 0.000 0.000 0.000 0.000
221.6 7.16 0.015 0.015 0.000 0.000 0.000 0.000 0.000

Summary statistics for above PSHA PGA deaggregation, R=distance, e=epsilon:
Contribution from this GMPE(%): 15.2
Mean src-site R= 58.4 km; M= 5.87; eps0= 0.70. Mean calculated for all sources.
Modal src-site R= 33.5 km; M= 5.40; eps0= 0.74 from peak (R,M) bin
MODE R*= 30.9km; M*= 4.80; EPS.INTERVAL: 0 to 1 sigma % CONTRIB.= 0.662

Principal sources (faults, subduction, random seismicity having > 3% contribution)
Source Category: % contr. R(km) M epsilon0 (mean values).
CEUS gridded 15.19 58.4 5.87 0.70
Individual fault hazard details if its contribution to mean hazard > 2%:
Fault ID % contr. Rcd(km) M epsilon0 Site-to-src azimuth(d)
#*********End of deaggregation corresponding to Silva 1-corner *********#

PSHA Deaggregation. %contributions. site: White_Mesa long: 109.500 W., lat: 37.500
N.
Vs30(m/s)= 760.0 (some WUS atten. models use Site Class not Vs30).
NSHMP 2007-08 See USGS OFR 2008-1128. dM=0.2 below
Return period: 9900 yrs. Exceedance PGA =0.1511 g. Weight * Computed_Rate_Ex
0.142E-04
#Pr[at least one eq with median motion>=PGA in 50 yrs]=0.00371
#This deaggregation corresponds to Tavakoli and Pezeshk 05
DIST(KM) MAG(MW) ALL_EPS EPSILON>2 1<EPS<2 0<EPS<1 -1<EPS<0 -
2<EPS<-1 EPS<-2
14.2 4.60 0.603 0.279 0.323 0.000 0.000 0.000 0.000
34.9 4.62 0.018 0.018 0.000 0.000 0.000 0.000 0.000
15.6 4.80 1.361 0.620 0.742 0.000 0.000 0.000 0.000
36.2 4.81 0.089 0.089 0.000 0.000 0.000 0.000 0.000
17.3 5.03 1.223 0.489 0.734 0.000 0.000 0.000 0.000
37.3 5.04 0.166 0.166 0.000 0.000 0.000 0.000 0.000
12.6 5.21 0.292 0.060 0.233 0.000 0.000 0.000 0.000
29.1 5.21 0.373 0.239 0.134 0.000 0.000 0.000 0.000
55.3 5.21 0.008 0.008 0.000 0.000 0.000 0.000 0.000
12.7 5.39 0.446 0.086 0.360 0.000 0.000 0.000 0.000
30.3 5.40 0.812 0.452 0.361 0.000 0.000 0.000 0.000
57.5 5.42 0.038 0.038 0.000 0.000 0.000 0.000 0.000
12.9 5.61 0.218 0.041 0.177 0.000 0.000 0.000 0.000
31.7 5.62 0.578 0.278 0.301 0.000 0.000 0.000 0.000
59.7 5.62 0.054 0.054 0.000 0.000 0.000 0.000 0.000
89.2 5.63 0.008 0.008 0.000 0.000 0.000 0.000 0.000
12.9 5.80 0.191 0.035 0.156 0.000 0.000 0.000 0.000
33.0 5.81 0.669 0.283 0.386 0.000 0.000 0.000 0.000
60.8 5.81 0.105 0.105 0.000 0.000 0.000 0.000 0.000
90.1 5.82 0.028 0.028 0.000 0.000 0.000 0.000 0.000
115.3 5.83 0.024 0.024 0.000 0.000 0.000 0.000 0.000
13.6 6.01 0.162 0.030 0.132 0.000 0.000 0.000 0.000
34.7 6.01 0.546 0.184 0.362 0.000 0.000 0.000 0.000
58.2 6.01 0.141 0.139 0.002 0.000 0.000 0.000 0.000
85.6 6.02 0.064 0.064 0.000 0.000 0.000 0.000 0.000
118.6 6.02 0.062 0.062 0.000 0.000 0.000 0.000 0.000
17.0 6.23 0.248 0.045 0.202 0.000 0.000 0.000 0.000
37.3 6.20 0.509 0.144 0.366 0.000 0.000 0.000 0.000
57.6 6.22 0.231 0.191 0.040 0.000 0.000 0.000 0.000
84.9 6.22 0.142 0.142 0.000 0.000 0.000 0.000 0.000
120.4 6.23 0.151 0.151 0.000 0.000 0.000 0.000 0.000
157.9 6.24 0.009 0.009 0.000 0.000 0.000 0.000 0.000
14.6 6.42 0.115 0.021 0.094 0.000 0.000 0.000 0.000
36.2 6.42 0.445 0.103 0.342 0.000 0.000 0.000 0.000
58.8 6.42 0.215 0.144 0.071 0.000 0.000 0.000 0.000
84.9 6.43 0.182 0.182 0.000 0.000 0.000 0.000 0.000
121.1 6.43 0.215 0.215 0.000 0.000 0.000 0.000 0.000
161.5 6.43 0.027 0.027 0.000 0.000 0.000 0.000 0.000
13.4 6.59 0.063 0.011 0.051 0.000 0.000 0.000 0.000
36.9 6.59 0.295 0.062 0.233 0.000 0.000 0.000 0.000
62.2 6.59 0.207 0.126 0.082 0.000 0.000 0.000 0.000
87.9 6.60 0.133 0.133 0.000 0.000 0.000 0.000 0.000
121.9 6.59 0.218 0.218 0.000 0.000 0.000 0.000 0.000
164.3 6.59 0.036 0.036 0.000 0.000 0.000 0.000 0.000
13.2 6.77 0.075 0.014 0.061 0.000 0.000 0.000 0.000
37.6 6.77 0.373 0.074 0.299 0.000 0.000 0.000 0.000
62.0 6.77 0.314 0.142 0.173 0.000 0.000 0.000 0.000
87.5 6.79 0.246 0.206 0.040 0.000 0.000 0.000 0.000
122.3 6.79 0.437 0.433 0.004 0.000 0.000 0.000 0.000
166.1 6.79 0.094 0.094 0.000 0.000 0.000 0.000 0.000
14.3 6.97 0.027 0.005 0.022 0.000 0.000 0.000 0.000
38.4 6.98 0.106 0.020 0.086 0.000 0.000 0.000 0.000
59.9 6.97 0.096 0.029 0.068 0.000 0.000 0.000 0.000
85.7 6.97 0.124 0.068 0.056 0.000 0.000 0.000 0.000
122.6 6.98 0.196 0.167 0.029 0.000 0.000 0.000 0.000
167.2 6.98 0.051 0.051 0.000 0.000 0.000 0.000 0.000
38.0 7.16 0.027 0.005 0.022 0.000 0.000 0.000 0.000
61.1 7.16 0.025 0.006 0.019 0.000 0.000 0.000 0.000
85.4 7.16 0.040 0.016 0.025 0.000 0.000 0.000 0.000
123.2 7.16 0.067 0.042 0.025 0.000 0.000 0.000 0.000
167.7 7.16 0.023 0.023 0.000 0.000 0.000 0.000 0.000

Summary statistics for above PSHA PGA deaggregation, R=distance, e=epsilon:
Contribution from this GMPE(%): 14.1
Mean src-site R= 44.4 km; M= 5.83; eps0= -0.21. Mean calculated for all sources.
Modal src-site R= 15.6 km; M= 4.80; eps0= -0.27 from peak (R,M) bin
MODE R*= 12.3km; M*= 4.80; EPS.INTERVAL: 0 to 1 sigma % CONTRIB.= 0.742

Principal sources (faults, subduction, random seismicity having > 3% contribution)
Source Category: % contr. R(km) M epsilon0 (mean values).
CEUS gridded 14.06 44.4 5.83 -0.21
Individual fault hazard details if its contribution to mean hazard > 2%:
Fault ID % contr. Rcd(km) M epsilon0 Site-to-src azimuth(d)
#*********End of deaggregation corresponding to Tavakoli and Pezeshk 05
*********#

PSHA Deaggregation. %contributions. site: White_Mesa long: 109.500 W., lat: 37.500
N.
Vs30(m/s)= 760.0 (some WUS atten. models use Site Class not Vs30).
NSHMP 2007-08 See USGS OFR 2008-1128. dM=0.2 below
Return period: 9900 yrs. Exceedance PGA =0.1511 g. Weight * Computed_Rate_Ex
0.381E-05
#Pr[at least one eq with median motion>=PGA in 50 yrs]=0.00086
#This deaggregation corresponds to Atkinson-Boore06,200 bar
DIST(KM) MAG(MW) ALL_EPS EPSILON>2 1<EPS<2 0<EPS<1 -1<EPS<0 -
2<EPS<-1 EPS<-2
9.3 4.61 0.146 0.084 0.062 0.000 0.000 0.000 0.000
10.3 4.80 0.357 0.207 0.150 0.000 0.000 0.000 0.000
11.7 5.03 0.353 0.178 0.175 0.000 0.000 0.000 0.000
12.9 5.21 0.171 0.081 0.090 0.000 0.000 0.000 0.000
33.9 5.21 0.002 0.002 0.000 0.000 0.000 0.000 0.000
14.1 5.40 0.325 0.151 0.174 0.000 0.000 0.000 0.000
35.4 5.42 0.011 0.011 0.000 0.000 0.000 0.000 0.000
15.5 5.61 0.205 0.097 0.108 0.000 0.000 0.000 0.000
37.0 5.62 0.017 0.017 0.000 0.000 0.000 0.000 0.000
15.3 5.79 0.189 0.074 0.115 0.000 0.000 0.000 0.000
31.6 5.84 0.062 0.055 0.007 0.000 0.000 0.000 0.000
55.1 5.83 0.002 0.002 0.000 0.000 0.000 0.000 0.000
12.9 6.01 0.127 0.030 0.098 0.000 0.000 0.000 0.000
30.9 6.01 0.103 0.084 0.019 0.000 0.000 0.000 0.000
56.2 6.02 0.007 0.007 0.000 0.000 0.000 0.000 0.000
15.6 6.22 0.180 0.045 0.135 0.000 0.000 0.000 0.000
34.6 6.20 0.101 0.086 0.014 0.000 0.000 0.000 0.000
57.0 6.22 0.019 0.019 0.000 0.000 0.000 0.000 0.000
86.0 6.23 0.011 0.011 0.000 0.000 0.000 0.000 0.000
124.0 6.24 0.021 0.021 0.000 0.000 0.000 0.000 0.000
18.3 6.42 0.163 0.044 0.120 0.000 0.000 0.000 0.000
39.0 6.42 0.068 0.059 0.009 0.000 0.000 0.000 0.000
58.3 6.43 0.023 0.023 0.000 0.000 0.000 0.000 0.000
85.9 6.43 0.021 0.021 0.000 0.000 0.000 0.000 0.000
124.7 6.35 0.009 0.009 0.000 0.000 0.000 0.000 0.000
125.1 6.45 0.036 0.036 0.000 0.000 0.000 0.000 0.000
162.5 6.44 0.012 0.012 0.000 0.000 0.000 0.000 0.000
13.1 6.59 0.058 0.011 0.046 0.000 0.000 0.000 0.000
33.0 6.59 0.100 0.056 0.044 0.000 0.000 0.000 0.000
58.9 6.59 0.022 0.022 0.000 0.000 0.000 0.000 0.000
86.0 6.59 0.024 0.024 0.000 0.000 0.000 0.000 0.000
125.6 6.59 0.052 0.052 0.000 0.000 0.000 0.000 0.000
167.5 6.59 0.020 0.020 0.000 0.000 0.000 0.000 0.000
13.0 6.77 0.071 0.014 0.057 0.000 0.000 0.000 0.000
33.9 6.78 0.146 0.072 0.074 0.000 0.000 0.000 0.000
61.2 6.78 0.048 0.048 0.000 0.000 0.000 0.000 0.000
88.0 6.79 0.040 0.040 0.000 0.000 0.000 0.000 0.000
125.7 6.79 0.111 0.111 0.000 0.000 0.000 0.000 0.000
169.6 6.79 0.055 0.055 0.000 0.000 0.000 0.000 0.000
214.6 6.81 0.009 0.009 0.000 0.000 0.000 0.000 0.000
16.2 6.98 0.031 0.006 0.025 0.000 0.000 0.000 0.000
36.9 6.97 0.041 0.019 0.022 0.000 0.000 0.000 0.000
59.2 6.97 0.018 0.018 0.000 0.000 0.000 0.000 0.000
86.2 6.98 0.022 0.022 0.000 0.000 0.000 0.000 0.000
124.7 7.07 0.009 0.009 0.000 0.000 0.000 0.000 0.000
125.7 6.96 0.042 0.042 0.000 0.000 0.000 0.000 0.000
170.7 6.98 0.029 0.029 0.000 0.000 0.000 0.000 0.000
218.5 6.98 0.008 0.008 0.000 0.000 0.000 0.000 0.000
13.8 7.16 0.005 0.001 0.004 0.000 0.000 0.000 0.000
35.2 7.16 0.014 0.005 0.009 0.000 0.000 0.000 0.000
60.4 7.16 0.005 0.005 0.000 0.000 0.000 0.000 0.000
85.8 7.16 0.008 0.008 0.000 0.000 0.000 0.000 0.000
125.6 7.16 0.018 0.018 0.000 0.000 0.000 0.000 0.000
171.2 7.16 0.012 0.012 0.000 0.000 0.000 0.000 0.000
219.9 7.16 0.004 0.004 0.000 0.000 0.000 0.000 0.000

Summary statistics for above PSHA PGA deaggregation, R=distance, e=epsilon:
Contribution from this GMPE(%): 3.8
Mean src-site R= 36.7 km; M= 5.89; eps0= 0.31. Mean calculated for all sources.
Modal src-site R= 10.3 km; M= 4.80; eps0= 0.25 from peak (R,M) bin
MODE R*= 12.3km; M*= 4.80; EPS.INTERVAL: 0 to 1 sigma % CONTRIB.= 0.207

Principal sources (faults, subduction, random seismicity having > 3% contribution)
Source Category: % contr. R(km) M epsilon0 (mean values).
CEUS gridded 3.77 36.7 5.89 0.31
Individual fault hazard details if its contribution to mean hazard > 2%:
Fault ID % contr. Rcd(km) M epsilon0 Site-to-src azimuth(d)
#*********End of deaggregation corresponding to Atkinson-Boore06,200 bar
*********#

******************** Intermountain Seismic
Belt***********************************

APPENDIX 4: DETERMINATION OF PEAK GROUND
ACCELERATIONS (PGA) USING CAMPBELL AND
BOZORGNIA (2007)

CALCUATION OF GROUND MOTION FORCAMPBELL-BOZO RGNIA NGA MODEL (MAR 2008,EARTHQUAKE SPECTRA);
ExplanatorvVariables Geometric Mean and Arbitrary HorizontalComponents
,'\1 GMP T (s)Median a o ,'"'""_Median
5.49 PSA (g)0.010 2.221E-02 -0.0065 0.4761 0.2190 0.1660 0.5241 0.5497 +sigma
0.020 2.249E-02 -0.0067 0.4781 0.2190 0.1660 0.5258 0.5514
RRUP 0.030 2.364E-02 -0.0081 0.4867 0.2350 0.1650 0.5404 0.5651
57.40 0.050 2.778E-02 -0.0125 0.5064 0.2580 0.1620 0.5683 0.5910
0.075 3.490E-02 -0.0147 0.5159 0.2920 0.1580 0.5928 0.6135
R"0.10 4.211E-02 -0.0144 0.5270 0.2860 0.1700 0.5996 0.6233
57.40 0.15 5.324E-02 -0.0110 0.5290 0.2800 0.1800 0.5985 0.6250
0.20 5.352E-02 -0.0068 0.5322 0.2490 0.1860 0.5875 0.6163
F"0.25 4.702E·02 -0.0031 0.5332 0.2400 0.1910 0.5847 0.6151
0 0.30 4.173E-02 0.0000 0.5440 0.2150 0.1980 0.5849 0.6175
0.40 3.216E-02 0.0000 0.5410 0.2170 0.2060 0.5829 0.6182
F••0.50 2.604E-02 0.0000 0.5500 0.2140 0.2080 0.5902 0.6257
0.75 1.565E-02 0.0000 0.5680 0.2270 0.2210 0.6117 0.6504
1.0 1.012E-02 0.0000 0.5680 0.2550 0.2250 0.622£ 0.6620
ZroR 1.5 5.153E-03 0.0000 0.5640 0.2960 0.2220 0.6370 0.6745
3.00 2.0 2.884E-03 0.0000 0.5710 0.2960 0.22£0 0.6432 0.6817
3.0 1.221E-03 0.0000 0.5580 0.3260 0.2290 0.6463 0.6856
0 4.0 6.337E-04 0.0000 0.5760 0.2970 0.2370 0.6481 0.6900
60 5.0 3.953E·04 0.0000 0.6010 0.3590 0.2370 0.7001 0.7391
7.5 1.739E-04 00000 0.6280 0.4280 0.2710 0.7600 0.8069V,.10.0 9.719E-05 0.0000 0.6670 0.4850 0,2900 0.8247 0.8742
586
PGA(g)0 2.221E-02 I -0.0065 0.4761 0.2190 0.1660 0.5241 0.5497 ~
Zu PGV (cIs)-,1.063E+00 0.0000 0.4840 0.2030 0.1900 0.5248 0.5582
000 PGD(cm)-2 2.413E-01 0.0000 0.6670 0.4850 0.2900 0.8247 0.8742
Calculated Variables
A 1100
1.803E-02
DEFINITION OF PARAMETERS;
SOlo-Damped Pseudo-Absolute Acceleration
Response Spectrum
10 ~_
:§
c.ge•..0.1cu"i!;;•~
'"
0.01
Period (s)
100.1
0.001 -I---'--'...Ll.l.J.il1-_..L...L..Ll.l.lllj-_L..JL.L.LLUlj
0.01
=Pseudo-absoluteacceleration response spectrum (g: 5%damping)
=Peak ground acceleration (g)
=Peak ground velocity (cmfs)
=Peak ground displacement (em)
=Moment magnitude
=Closest distance to coseismicrupture (km)
=Closest distance to surface projection of coseismic rupture (km)
=Reverse-faulting factor;0 for strike slip, normal.normal-oblique:1 for reverse.reverse-oblique and thrust
=Normal-faulting factor; 0 for strikeslip,reverse,reverse-obliqueand mrust. 1 for normal and normal-oblique
=Depth to top of coseismic rupture (km)
=Average dip of rupture plane (degrees)
=Average shear-wave velocity in top 30m of site profile
PGA on rock with Vs30 =1100 mfs (g)
=Depth of 2.5 kmfs shear-wave velocityhcnzon [krn]
PSA
PGA
PGV
PGO
M
RRVP
R"
F"
F••
Z rolls
V~o
A 1100
Z 2.'
Unnamed fault possible extention of Shays graben defined length 3.0 km
5%-Damped Pseudo-Absolute Acceleration
Response Spectrum
CAl CUATIONOF GROUNDMOTION FOR CAMPBEl l -BOZORGNIA NGA MODEL (MAR 2008,EARTHQUAKE SPECTRA):
Explanatory Variables Geometric Mean and Arbitrary Horizontal Components
M GMP T(s)Median a o r u,u,U~Median
6.23 PSA (g)0.010 3.622E-02 -0.0104 0.4750 0.2190 0.1660 0.5230 0.5487 + sigma
0.020 3.667E-02 -0.0107 0.4769 0.2190 0.1660 0.5248 0.5504
R RUP 0.030 3.852E-02 -0.0130 0.4852 0.2350 0.1650 0.5391 0.5638
57.40 0.050 4.513E-02 -0.0202 0.5042 0.2580 0.1620 0.5664 0.5891
0.075 5.664E·02 -0.0236 0.5134 0.2920 0.1580 0.5906 0.6114
R"0.10 6.838E-02 -0.0231 0.5247 0.2860 0.1700 0.5975 0.6213
57.40 0.15 8.664E-02 -0.Q178 0.5271 0.2600 0.1600 0.5969 0.6234
0.20 9.283E-02 -0.0111 0.5310 0.2490 0.1860 0.5665 0.6153
F",0.25 8.689E-02 -0.0050 0.5327 0.2400 0.1910 0.5843 0.6147
0 0.30 8.119E-02 -0.0001 0.5440 0.2150 0.1980 0.5849 0.6175
0.40 6.769E-02 0.0000 0.5410 0.2170 0.2060 0.5629 0.6182
F."0.50 5.644E--Q2 0.0000 0.5500 0.2140 0.2060 0.5902 0.6257
0.75 3.507E-02 0.0000 0.5680 0.2270 0.2210 0.6117 0.6504
1.0 2.323E-02 0.0000 0.5680 0.2550 0.2250 0.6226 0.6620
ZroR 1.5 1.225E-02 0.0000 0.5640 0.2960 0.2220 0.6370 0.6745
3.00 2.0 7.683E·03 0.0000 0.5710 0.2960 0.2260 0.6432 0.6817
3.0 4.170E-03 0.0000 0.5580 0.3260 0.2290 0.6463 0.6856
6 4.0 2.737E-03 0.0000 0.5760 0.2970 0.2370 0.6481 0.6900
60 5.0 2.043E--Q3 0.0000 0,6010 0.3590 0.2370 0.7001 0.7391
7.5 8.990E-04 0.0000 0.6280 0.4280 0.2710 0.7600 0.8069
Vs,.10.0 5.024E-04 0.0000 0.6670 0.4650 0.2900 0.8247 0.8742
586
PGA(g)0 3.622E-02 I -0.0104 0.4750 0.2190 0.1660 0.5230 0.5487 ~
Z2.~PGV (cis).,2.365E+00 0.0000 0.4840 0.2030 0.1900 0.5248 0.5582
0.00 PGD (em)-2 1.247E+00 0.0000 0.6670 0.4850 0.2900 0.8247 0.8742
Calcu lated Variables
A mlO
2.952E-02
DEFINITIONOF PARAMETERS:
10
0.01 1\
PSA
PGA
PGV
PGD
"
::Pseudo-absolute acceleration response spectrum (g: 5%damping)
'"Peakground acceleration (g)
::Peakground velocity (cmls)
=Peak ground displacement (cm)
::Moment magnitude
::Closest distance to coseismic rupture (km)
=Closest distance to surtace projectionotcoseismic rupture (km)
::Reverse-faulting factor:0 for strike slip. normal,normal-oblique; 1 for reverse,reverse-oblique and thrust
::Normal-faulling factor:0 for strike slip,reverse,reverse-oblique and thrust; 1 for normal and normal-oblique
::Depth to lop of coseismic rupture (km)
::Average dipof rupture plane (degrees)
::Average shear-wave velocity in top 30m otsite profile
::PGA on rock withVs30 ::1100 mls (g)
::Depth of 2.5 kmls shear-wave velocity horizon (km)
0.001
0.01 0.1
Period (5)
10
Unnamedtault possibleextention ofShays graben total possible length 11.0 km
5%-Damped Pseudo-Absolute Acceleration
Response Spectrum
CALCUATION OF GROUND MOTION FOR CAMPBELL·BOZORGNIA NGA MODEL (MAR 2008,EARTHQUAKE SPECTRA);
Explanatory Variables Geometric Mean andArbitrary Horizontal Components
M GMP T {s) Median a U <Uc U,U~Median
5.84 PSA(g) 0.010 2.807E-02 -0.0081 0.4756 0.2190 0.1660 0.5236 0.5493 + sigma
0.020 2.843E-02 ·0.0084 0.4776 0.2190 0.1660 0.5254 0.5510
R f/u P 0.030 2.988E-02 -0.0101 0.4861 0.2350 0.1650 0.5399 0.5645
57.40 0.050 3.506E-02 -0.0158 0.5054 0.2580 0.1620 0.5675 0.5902
0.075 4.402E-02 -0.0184 0.5149 0.2920 0.1580 0.5919 0.6126
R"0.10 5.314E-02 -0.0181 0.5260 0.2860 0.1700 0.5988 0.6224
57.40 0.15 6.724E-02 -0.0139 0.5282 0.2800 0.1800 0.5978 0.6243
0.20 6.963E-02 -0.0086 0.5317 0.2490 0.1860 0.5871 0.6159F.,0.25 6.299E-02 -0.0039 0.5330 0.2400 0.1910 0.5845 0.6149
0 0.30 5.726E-02 -0.000 1 0.5440 0.2150 0.1980 0.5849 0.6175
0.40 4.577E-02 0.0000 0.5410 0.2170 0.2060 0.5829 0.6182
F."0.50 3.760E-02 0.0000 0.5500 0.2140 0.2080 0.5902 0.6257
0.75 2.299E-02 0.0000 0.5680 0.2270 0.2210 0.6117 0.6504
1.0 1.505E-02 0.0000 0.5680 0.2550 0.2250 0.6226 0.6620
zr»1.5 7.803E-03 0.0000 0.5640 0.2960 0.2220 0.6370 0.6745
3.00 2.0 4.608E-03 0.0000 0.5710 0.2960 0.2260 0.6432 0.6817
3.0 2.190E-03 0.0000 0.5580 0.3260 0.2290 0.6463 0.6856
Ii 4.0 1.268E-03 0.0000 0.5760 0.2970 0.2370 0.6481 0.6900
60 5.0 8.600E-04 0.0000 0.6010 0.3590 0.2370 0.7001 0.1391
7.5 3.784E·04 0.0000 0.6280 0.4280 0.2710 0.7600 0.8069
v,~10.0 2.114E·04 0.0000 0.6670 0.4850 0.2900 0.8247 0.8742
586
PGA {g)0 I 2.807E.Q2 I -0.0081 0.4756 0.2190 0.1660 0.5236 0.5493 ~
Z2,S PGV (cIs )
.,1.554E+00 0.0000 0.4840 0.2030 0.1900 0.5248 0.5582
0.00 PGO (em)·2 5.249E-01 0.0000 0.6670 0.4850 0.2900 0.8247 0.8742
Calculated Variables
A n oo
2.283E·02
DEFINITION OF PARAMETER S:
10
0.1
0.01 1\
PSA
PGA
PGV
PGO
M
R RUP
R"F.,
F."
Zro.s
V~.
A"""Zu
'"Pseudo-absolute acceleration response spectrum (g: 5% damping)
'"Peak ground acceleration (g)
'"Peakgroundvelocity (cmls)
'"Peak ground displacement (em)
'"Moment magnitude
'"Closest distance to coseismic rupture (km)
'"Closest distance to surface projection 01coseismic rupture (km)
'"Reverse-faulting tactor:0 for strike slip,normal.normal-oblique:1 for reverse.reverse -oblique and thrust
'"Normal·faulting factor:0 torstrike slip,reverse,reverse-oblique and thrust; 1 lor normal and normsr-obnque
'"Depth to top 01coseismic rupture (km)
'"Average dip of rupture plane (degrees)
'"Average shear-wave velocity in top 30m of site profile
'"PGA on rock with Vs30 '"1100 mfs (g)
'"Depth 012.5 kmfsshear-wave velocity horizon(km)
0.001
0.01 0.1
Period (s)
10
Unnamed fault possible extenucn of steve graben 1/2 lotal ruplure 5.5 km
10
5%-Oamped Pseudo-Absolute Acceleration
Respon se Spectrum
CALCUATIONOF GROUND MOTIONFOR CAMPBELL·BOZORGNIA NGA MODEL (MAR 2008, EARTHQUAK ESPECTRA):
Explanatory Variable s GeometricMean and Arbitrary Horizontal Components
"GMP T (s)Median a a <a ,a,a_Median
6.97 PSA(g}0.010 5.192E-02 -0.0148 0.4737 0.2190 0.1660 0.5219 0.5477 + sigma
0.020 5.257E-02 -0.0152 0.4756 0.2190 0.1660 0.5236 0.5493
R RUP 0.030 5.516E-02 -0.0184 0.4837 0.2350 0.1650 0.5376 0.5625
57.40 0.050 6.428E-02 -0.0285 0.5018 0.2580 0.1620 0.5642 0.5870
0.D75 7.926E-02 -0.0333 0.5107 0.2920 0.1580 0.5883 0.6092
R"0.10 9.475E-02 -0.0327 0.5221 0.2860 0.1700 0.5953 0.6191
57.40 0.15 1.195E-01 -0.0252 0.5251 0.2800 0.1800 0.5951 0.6218
0.20 1.329E-01 -0.0157 0.5298 0.2490 0.1860 0.5854 0.6142
F"0.25 1.290E-01 -0.0071 0.5321 0.2400 0.1910 0.5838 0.6142
0 0.30 1.239E-01 -0.0001 0.5440 0.2150 0.1980 0.5849 0.6175
0.40 1.077E-01 0.0000 0.5410 0.2170 0.2060 0.5829 0.6182F,.0.50 9.478E-02 0.0000 0.5500 0.2140 0.2080 0.5902 0.6257
0.75 6.458E-02 0.0000 0.5680 0.2270 0.2210 0.6117 0.6504
1.0 4.566E-02 0.ססOO 0.5680 0.2550 0.2250 0.6226 0.6620
Z TOR 1.5 2.641E-02 0.0000 0.5640 0.2960 0.2220 0.6370 0.6745
3.00 2.0 1.814E-02 0.0000 0.5710 0.2960 0.2260 0.6432 0.6817
3.0 1.123E-02 0.ססOO 0.5580 0.3260 0.2290 0.6463 0.6856
0 4.0 8.208E-03 0.0000 0.5760 0.2970 0.2370 0.6481 0.6900
60 5.0 6.640E-03 0.ססOO 0.6010 0.3590 0.2370 0.7001 0.7391
7.5 3.412E-03 0.0000 0.6280 0.4280 0.2710 0.7600 0.8069
VS 30 10.0 2.128E-03 0.0000 0.6670 0.4850 0.2900 0.8247 0.8742
586
PGA (g)0 5.192E-02 I -0.0148 0.4737 0.2190 0.1660 0.5219 0.5477 ~
Z 2.S PGV{c/s)-,5.196E+00 0.0000 0.4840 0.2030 0.1900 0.5248 0.5582
0.00 PGD(cm)·2 6.442E+OO 0.0000 0.6670 0.4850 0.2900 0.8247 0.8742
Calcu lated Variables
A1100
4.252E-02
DEFINITIONOF PARAMETEFlS:
§
c0.~
•..0.1uc'"~13•0.oo
0.01
/'f-
"1\
PSA
PGA
PGV
PGO
1\1
R RUP
R"
F"
F••
Z ro.s
V~.
A1100
Zu
=Pseudo-absolute acceleration response spectrum (g:5%damping)
=Peak ground acceleration (g)
=Peak ground velocity (cm/s)
=Peak ground displacement(em)
=Moment magnitude
=Closest distance to coseismicrupture (km)
=Closest distance to surface projection of coseismic rupture (km)
Reverse-faulting factor: 0 for strikeslip.normal.normal-oblique:1 for reverse.reverse-oblique and thrust
=Normal-faulfing factor:0 lor strike slip,reverse,reverse-oblique and thrust:1for normal and normal-oblique
=Depth totop of coseismic rupture (km)
=Average dip of rupture plane (degrees)
=Average shear-wave velocity in top 30m of site profile
=PGA on rock with Vs30 =1100 mls (9)
=Depth of 2.5 kmls shear-wavevelocity nortzon (km)
Shay graben faults (Class B)40.0 km
0.001
0.01 0.1
Period (5)
10
CALCUATION OF GROUND MOTION FOR CAMPBELL-BOZORGNIA NGA MODEL (MAR 2008,EARTHQUAKE SPECTRA):
Explanatory Variables GeometricMean and Arbitrary Horizontal Components
M GMP T (s)Median a o r u ,u ,U_Medi an
6.30 PSA (g)0.010 1.409E·Ol -0.0372 0.4673 0.2190 0.1660 0.5161 0.5421 + sigma
0.020 l.434E-Ol -0.0383 0.4690 0.2190 0.1660 0.5176 0.5436
R RUP 0.030 1.540E-Ol -0.0461 0.4757 0.2350 0.1650 0.5306 0.5557
15.00 0.050 1.889E-01 -0.0707 0.4898 0.2580 0.1620 0.5536 0.5768
0.075 2.503E·Ol -0.0825 0.4973 0.2920 0.1580 0.5767 0.5979
R"0.10 3.092E-01 -0.0813 0.5090 0.2860 0.1700 0.5838 0.6081
15.00 0.15 3.840E·01 -0.0634 0.5149 0.2800 0.1800 0.5861 0.6131
0.20 3.923E-01 -0.0399 0.5234 0.2490 0.1860 0.5796 0.6087
F"0.25 3.5l9E-Ol -0.0182 0.5293 0.2400 0.1910 0.5811 0.6117
0 0.30 3.l80E-Ol -0.0003 0.5439 0.2150 0.1980 0.5849 0.6175
0.40 2.6l4E-Ql 0.0000 0.5410 0.2170 0.2060 0.5829 0.6182
F."0.50 2.138E-Ql 0.0000 0.5500 0.2140 0.2080 0.5902 0.6257
0.75 1.278E-01 0.0000 0.5680 0.2270 0.2210 0.6117 0.6504
1.0 8.480E-02 0.0000 0.5680 0.2550 0.2250 0.6226 0.6620
ZroR 1.5 4.485E-02 0.0000 0.5640 0.2960 0.2220 0.6370 0.6745
3.00 2.0 2.844E-02 0.0000 0.5710 0.2960 0.2260 0.6432 0.6817
3.0 1.581E-02 0.0000 0.5580 0.3260 0.2290 0.6463 0.6856s4.0 1.061E-02 0.ססOO 0.5760 0.2970 0.2370 0.6481 0.6900
60 5.0 8.060E-03 0.0000 0.6010 0.3590 0.2370 0.7001 0.7391
7.5 3.546E-03 0.0000 0.6280 0.4280 0.2710 0.7600 0.8069
V,.10.0 1.982E·03 0.0000 0.6670 0.4850 0.2900 0.8247 0.8742
566
PGA(g)0 I 1.409E-01 I -0.0372 0.4673 0.2190 0.1660 0.5161 0.5421 ~
Z 2.5 PGV(cJs)·1 8.793E+00 0.0000 0.4640 0.2030 0.1900 0.5248 0.5582
0.00 PGO (em)·2 4.919E...00 0.0000 0.6670 0.4650 0.2900 0.8247 0.8742
Calculated Variables
A 1100
1.183E-01
DEFINITION OF PARAMETERS:
5%-Damped Pseudo-Absolute Acceleration
Response Spectrum
10 ~_
0.,_
0.
01 11II..
PS.
PG'
PGV
PGO
M
R RVP
R"F.,
F."
Z roRs
V~
A 1100
Z2.5
Pseudo-absolute acceleration response spectrum (g: 5%damping)
Peak ground acceleration (g)
Peak ground velocity (cm/s)
'" Peak ground displacement(cm)
'" Moment magnitude
'" Closest distance 10coseismic rupture (km)
'" Closest distance to surface projection of coseismic rupture (km)
'"Reverse-faulting factor: 0 for strikeslip,normal.normal-oblique;1 for reverse,reverse-oblique and thrust
'"Normal-faulting factor:0 for strike slip,reverse,reverse-oblique and thrust: 1 for normal and normal-oblique
'" Depth to top of coseismic rupture (km)
'"Average dip of rupture plane (degrees)
'"Average shear-wave velocity in top 30m ofsite profile
'"PGA on rock with Vs30 ""1100 mfs (9)
==Depth of 2.5 kmls shear-wavevelocity horizon (km)
0.001
0.01 0.1
Period(s)
10
Floating Earthquake -Conservative Assorrotion

ATTACHMENT 3

TABULATED LISTS OF HISTORICAL EARTHQUAKES NEAR THE WHITE MESA MILL

ATTACHMENT 3.1

HISTORICAL EARTHQUAKES WITH MAGNITUDE 4.0 OR GREATER WITHIN A 200-MILE
RADIUS OF WHITE MESA MILL

Catalog ID Number Magnitude
Longitude
(degrees east)
Latitude
(degrees north)Date
CEUS 3 5.0 -107.5 39 9/9/1944
CEUS 4 5.0 -109.5 35.7 1/17/1950
CEUS 6 4.3 -110.163 38.997 7/30/1953
CEUS 11 5.5 -107.6 38.3 10/11/1960
CEUS 14 4.6 -110.33 39.44 4/24/1963
CEUS 15 4.5 -111.22 38.1 9/30/1963
CEUS 20 4.0 -110.29 39.36 11/4/1964
CEUS 22 4.5 -110.35 39.44 1/14/1965
CEUS 25 4.1 -110.36 39.44 7/30/1966
CEUS 26 4.2 -107.6 38.3 9/4/1966
CEUS 30 4.4 -107.51 38.98 1/12/1967
CEUS 31 4.1 -107.86 37.67 1/16/1967
CEUS 36 4.5 -107.75 38.32 4/4/1967
CEUS 42 4.0 -108.31 37.92 2/3/1970
CEUS 43 4.3 -107.31 39.49 1/7/1971
CEUS 46 4.0 -108.68 38.91 11/12/1971
CEUS 49 4.4 -108.65 39.27 1/30/1975
CEUS 51 4.6 -108.212 35.817 1/5/1976
CEUS 55 4.2 -108.222 35.748 3/5/1977
CEUS 56 4.0 -107.31 39.31 9/24/1977
CEUS 84 4.0 -110.574 37.42 8/22/1986
CEUS 92 5.5 -110.869 39.128 8/14/1988
CEUS 104 4.4 -107.976 38.151 9/13/1994
CEUS 107 4.2 -108.925 40.179 3/20/1995
CEUS 108 4.3 -110.878 39.12 1/6/1996
WUS 134 5.7 -112.522 37.047 12/5/3787
WUS 138 6.5 -112.084 38.769 11/14/1901
WUS 139 4.3 -112.639 38.279 7/31/1902
WUS 144 5.0 -113.007 38.393 4/15/1908
WUS 146 5.0 -112.15 38.683 1/10/1910
WUS 148 5.5 -111.5 36.5 8/18/1912
WUS 158 6.3 -112.15 38.683 9/29/1921
WUS 162 5.0 -112.827 37.842 1/20/1933
WUS 165 5.0 -112.1 36 1/10/1935
WUS 169 4.3 -112.958 37.25 5/9/1936
WUS 171 4.3 -112.433 37.822 2/18/1937
WUS 174 4.3 -111.65 39.58 6/4/1942
WUS 175 5.0 -113.066 37.683 8/30/1942
WUS 177 4.3 -112.26 38.58 11/3/1943
WUS 178 5.0 -111.987 38.765 11/18/1945
WUS 181 4.3 -111.637 39.263 11/4/1948
WUS 186 5.0 -111.9 38.5 11/18/1950
WUS 190 4.3 -112.433 37.822 10/22/1953
WUS 193 5.0 -107.3 38 8/3/1955
WUS 195 4.3 -111.833 39.711 11/28/1958
WUS 196 5.0 -112.5 38 2/27/1959
Table 1: Historical Earthquakes with Magnitude 4.0 or Greater
Within a 200-Mile Radius of White Mesa Mill
1 of 2
Catalog ID Number Magnitude
Longitude
(degrees east)
Latitude
(degrees north)Date
WUS 197 5.5 -112.5 37 7/21/1959
WUS 198 5.0 -111.5 35.5 10/13/1959
WUS 199 5.0 -111.66 39.34 4/16/1961
WUS 200 4.7 -107.6 38.2 2/5/1962
WUS 201 4.5 -112.4 36.9 2/15/1962
WUS 202 4.4 -112.9 37 2/15/1962
WUS 203 4.5 -112.1 38 6/5/1962
WUS 206 4.3 -111 40 9/7/1962
WUS 208 5.0 -111.91 39.53 7/7/1963
WUS 209 4.0 -111.19 40.03 7/9/1963
WUS 212 4.1 -112.85 37.97 1/18/1965
WUS 215 4.1 -111.85 37.98 5/20/1966
WUS 216 4.4 -111.6 35.8 10/3/1966
WUS 219 4.2 -112.3 38.8 6/22/1967
WUS 220 4.2 -111.6 36.15 9/4/1967
WUS 221 5.5 -112.157 38.543 10/4/1967
WUS 222 4.1 -112.21 38.75 6/18/1969
WUS 227 4.4 -112.17 38.65 1/3/1972
WUS 228 4.0 -112.07 38.67 6/2/1972
WUS 230 4.5 -106.17 36.09 3/17/1973
WUS 231 4.2 -111.43 39.1 7/16/1973
WUS 232 4.1 -107.74 35.26 12/24/1973
WUS 233 4.2 -111.5 39.15 10/6/1975
WUS 238 4.3 -111.62 35.17 12/6/1981
WUS 239 4.0 -112.04 38.71 5/24/1982
WUS 243 4.4 -112.009 39.236 3/24/1986
WUS 245 5.3 -111.62 38.829 1/30/1989
WUS 246 4.0 -112.257 35.952 3/5/1989
WUS 250 4.2 -112.355 35.96 3/14/1992
WUS 252 4.4 -111.554 38.783 6/24/1992
WUS 253 4.0 -112.219 35.982 7/5/1992
WUS 256 5.3 -112.112 35.611 4/29/1993
WUS 257 4.3 -112.327 38.078 9/6/1994
WUS 258 4.1 -112.223 35.964 4/17/1995
WUS 260 4.9 -112.52 38.225 1/2/1998
WUS 262 4.2 -112.49 37.97 6/18/1998
WUS 263 4.2 -112.727 38.077 10/22/1999
WUS 264 4.1 -112.56 38.73 2/23/2001
WUS 265 4.3 -111.521 38.731 7/19/2001
WUS 266 4.4 -111.857 39.516 4/17/2003
NEIC 270 4.6 -112.34 38.247 1/3/2011
NEIC 271 4.2 -112.089 37.811 4/12/2012
Table 1: Historical Earthquakes with Magnitude 4.0 or Greater
Within a 200-Mile Radius of White Mesa Mill (continued)
Notes:
1) Earthquakes are sorted by date of occurrence.
2) ID Numbers correlate to those shown on Figure 1.
3) WUS = Western United States (Petersen et al., 2008)
4) CEUS = Central & Eastern United States (Peterson et al., 2008)
5) NEIC = National Earthquake Information Center
2 of 2

ATTACHMENT 3.2

HISTORICAL EARTHQUAKES WITH MAGNITUDE 2.4 OR GREATER WITHIN AN 80-MILE
RADIUS OF WHITE MESA MILL

Catalog ID Number Magnitude
Longitude
(degrees east)
Latitude
(degrees north)Date
PDE 303 3.1 -110.542 37.511 9/10/1981
PDE 304 3.2 -110.592 38.288 5/3/1983
PDE 305 2.7 -110.409 37.556 8/4/1983
PDE 307 3.2 -110.561 37.429 5/14/1986
PDE 308 4.0 -110.574 37.42 8/22/1986
PDE 309 2.5 -108.118 37.635 9/9/1987
PDE 310 3.1 -108.924 38.473 5/13/1989
PDE 311 3.0 -110.358 37.209 6/25/1991
PDE 315 3.0 -108.827 38.268 4/10/1998
PDE 316 3.6 -108.921 38.293 6/3/1999
PDE 317 3.5 -108.859 38.319 7/6/1999
PDE 318 2.9 -108.907 38.31 9/16/1999
PDE 319 2.9 -108.88 38.27 10/11/1999
PDE 320 2.9 -108.81 38.24 11/4/1999
PDE 321 3.3 -108.867 38.367 3/15/2000
PDE 322 4.3 -108.859 38.341 5/27/2000
PDE 323 3.2 -108.93 38.34 6/6/2002
PDE 324 3.0 -110.53 37.41 9/26/2002
PDE 325 2.9 -110.56 38.324 12/29/2003
PDE 326 4.1 -108.915 38.236 11/7/2004
PDE 328 2.9 -108.91 38.26 8/7/2005
PDE 329 2.8 -108.98 38.38 8/1/2007
PDE 330 3.7 -109.47 37.36 6/6/2008
PDE 331 2.6 -110.68 37.15 9/7/2008
PDE 332 2.8 -110.56 38.332 2/19/2009
PDE 333 3.0 -110.45 37.66 3/31/2009
PDE 334 2.9 -110.42 37.65 4/14/2009
PDE 335 2.6 -108.98 38.37 4/19/2009
PDE 336 2.5 -108.914 38.258 4/30/2009
PDE 337 2.7 -110.44 37.64 6/9/2009
PDE 338 3.3 -110.77 37.01 7/13/2009
PDE 339 2.9 -108.87 38.36 11/17/2009
PDE-W 340 2.5 -110.17 37.15 1/18/2011
PDE-Q 341 2.7 -109.69 38.45 3/6/2012
Table 2: Historical Earthquakes with Magnitude 2.4 or Greater
Within a 200-Mile Radius of White Mesa Mill
Notes:
1) Earthquakes are sorted by date of occurrence.
2) ID Numbers correlate to those shown on Figure 2.3) More information about the PDE catalogs can be found on the USGS website: 4)
<http://earthquake.usgs.gov/earthquakes/egarchives/epic/code_catalog.php>
1 of 1

ATTACHMENT 4

US GEOLOGICAL SURVEY PSHA DEAGREGGATION DATA

ATTACHMENT 4.1

US GEOLOGICAL SURVEY DEAGGREGATION DATA

2,475 YEAR RETURN PERIOD

Page 1 of 14
***Deaggregation of Seismic Hazard at One Period of Spectral Aceel.***
***Data from U.S.G.B.National Seismic Hazards Mapping Project,2008 version ***
PSHA Deaggregation.%contributions.site:Denison_white_M long:109.500 W.,lat:37.500 N.
Vs30(m/s)=760.0 (some was atten.models use Site Class not Vs30).
NSHMP 2007-08 See USGS OFR 2008-1128.dM=0.2 below
Return period:2475 yrs.Exceedance PGA =0.07011 g.Weight *Cornputed_Rate_Ex O.40BE-03
#Pr[at least one eq with median motion>=PGA in 50 yrs]=O.00709
#This deaggregation corresponds to Mean Hazard w/all GMPEs
DIST(KM)MAG(MW)ALL_EPS EPSILON>2
12.3 4.60 1.228 0.039
32.2 4.61 2.149 0.330
62.6 4.61 0.484 0.433
88.9 4.62 0.102 0.102
12.4 4.80 2.193 0.064
32.9 4.80 4.709 0.543
63.0 4.81 1.346 0.995
89.4 4.81 0.372 0.372
114.0 4.82 0.190 0.190
12.6 5.03 1.542 0.041
33.9 5.03 4.328 0.350
63.7 5.04 1.738 0.859
89.8 5.04 0.632 0.626
117.8 5.05 0.528 0.528
12.7 5.21 0.580 0.015
34.6 5.21 1.968 0.125
64.1 5.21 0.998 0.316
90.0 5.21 0.425 0.370
119.5 5.21 0.443 0.443
12.8 5.39 0.870 0.021
35.3 5.40 3.478 0.182
64.6 5.40 2.189 0.458
90.1 5.40 1.080 0.586
120.8 5.41 1.352 1.278
165.3 5.41 0.252 0.252
12.8 5.61 0.422 0.010
36.0 5.61 2.019 0.086
65.1 5.62 1.640 0.216
90.3 5.62 0.955 0.276
121.8 5.62 1.401 0.941
167.6 5.62 0.389 0.389
12.9 5.80 0.369 0.009
36.4 5.80 1.966 0.074
62.6 5.79 1.448 0.136
86.5 5.82 1.630 0.288
122.5 5.81 2.005 0.890
168.6 5.81 0.684 0.672
216.8 5.82 0.122 0.122
13.5 6.01 0.314 0.007
36.8 6.01 1.402 0.046
59.8 6.01 1.230 0.072
85.2 6.01 1.772 0.197
123.0 6.01 2.334 0.573
170.3 6.01 0.928 0.724
218.4 6.02 0.231 0.231
16.4 6.20 0.473.0.011
37.8 6.22 1.256 0.038
60.2 6.21 1.356 0.066
85.3 6.22 2.101 0.173
123.5 6.22 3.153 0.506
170.9 6.22 1.479 0.764
219.4 6.22 0.437 0.437
268.2 6.23 0.090 0.090
14.0 6.42 0.227 0.005
37.0 6.42 0.977 0.027
1<EPS<2 O<EPS<l -l<EPS<O
0.232 0.582 0.350
1.209 0.610 0.000
0.051 0.000 0.000
0.000 0.000 0.000
0.381 0.957 0.724
2.477 1.679 0.010
0.351 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.246 0.618 0.567
1.990 1.851 0.137
0.879 0.000 0.000
0.006 0.000 0.000
0.000 0.000 0.000
0.088 0.221 0.214
0.750 0.960 0.133
0.680 0.002 0.000
0.054 0.000 0.000
0.000 0.000 0.000
0.128 0.321 0.319
1.086 1.845 0.365
1.608 0.122 0.000
0.494 0.000 0.000
0.074 0.000 0.000
0.000 0.000 0.000
0.060 0.151 0.151
0.511 1.106 0.315
1.116 0.308 0.000
0.679 0.000 0.000
0.460 0.000 0.000
0.000 0.000 0.000
0.052 0.130 0.130
0.441 1.061 0.385
0.787 0.525 0.000
1.268 0.074 0.000
1.115 0.000 0.000
0.012 0.000 0.000
0.000 0.000 0.000
0.044 0.110 0.110
0.272 0.684 0.390
0.431 0.718 0.009
1.163 0.411 0.000
1.747 0.015 0.000
0.204 0.000 0.000
0.000 0.000 0.000
0.066 0.167 0.167
0.227 0.571 0.403
0.396 0.837 0.057
1.031 0.896 0.000
2.394 0.253 0.000
0.715 0.000 0.000
0.001 0.000 0.000
0.000 0.000 0.000
0.031 0.078 0.078
0.161 0.405 0.352
-2<EPS<-1
0.026
0.000
0.000
0.000
0.068
0.000
0.000
0.000
0.000
0.069
0.000
0.000
0.000
0.000
0.042
0.000
0.000
0.000
0.000
0.080
0.000
0.000
0.000
0.000
0.000
0.048
0.000
0.000
0.000
0.000
0.000
0.047
0.006
0.000
0.000
0.000
0.000
0.000
0.041
0.011
0.000
0.000
0.000
0.000
0.000
0.058
0.018
0.000
0.000
0.000
0.000
0.000
0.000
0.031
0.031
EPS<-2
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.001
0.000
0.000
0.000
0.000
0.001
0.000
0.000
0.000
0.000
0.002
0.000
0.000
0.000
0.000
0.000
0.002
0.000
0.000
0.000
0.000
0.000
0.002
0.000
0.000
0.000
0.000
0.000
0.000
0.003
0.000
0.000
0.000
0.000
0.000
0.000
0.003
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.003
0.000
https:llgeohazards.usgs.gov/deaggintI2008/outlDenison_White_M_2012.05.25_15.24.10.txt 512512012
Page 2 of 14
60.5
85.2
124.1
171.3
219.9
269.6
12.9
37.4
62.7
87.1
124.9
171.9
220.5
269.9
339.3
13.5
37.7
60.6
85.5
124.8
125.7
172.6
220.9
270.7
345.8
351.6
13.9
38.4
61.6
86.0
124.7
125.7
172.6
221.5
271.2
354.2
65.8
90.4
126.0
173.8
221.4
6.42
6.42
6.42
6.42
6.43
6.43
6.59
6.59
6.60
6.59
6.59
6.59
6.59
6.60
6.60
6.78
6.77
6.78
6.78
6.74
6.86
6.78
6.78
6.79
6.74
6.86
6.97
6.97
6.97
6.97
6.95
7.01
6.97
6.97
6.97
6.98
7.16
7.16
7.16
7.16
7.16
0.997
1.788
3.032
1.684
0.608
0.155
0.129
0.623
0.733
1.101
2.169
1.380
0.540
0.160
0.070
0.165
0.715
0.828
1.546
2.102
1.018
2.175
0.956
0.312
0.111
0.072
0.052
0.233
0.235
0.497
0.767
0.295
0.861
0.391
0.146
0.104
0.091
0.095
0.257
0.229
0.123
0.040
0.107
0.308
0.478
0.486
0.155
0.003
0.017
0.027
0.057
0.171
0.281
0.301
0.158
0.070
0.004
0.018
0.027
0.066
0.133
0.085
0.315
0.323
0.253
0.111
0.072
0.001
0.006
0.007
0.018
0.036
0.033
0.098
0.078
0.071
0.101
0.003
0.003
0.011
0.016
0.017
0.237
0.632
1.814
1.202
0.121
0.000
0.018
0.099
0.160
0.336
1.018
1.044
0.239
0.002
0.000
0.023
0.110
0.161
0.390
0.797
0.333
1.494
0.634
0.058
0.000
0.000
0.007
0.035
0.042
0.106
0.213
0.080
0.434
0.308
0.075
0.003
0.016
0.019
0.064
0.095
0.092
0.587
1.048
0.910
0.003
0.000
0.000
0.044
0.249
0.401
0.703
0.980
0.055
0.000
0.000
0.000
0.057
0.276
0.404
0.957
1.172
0.600
0.365
0.000
0.000
0.000
0.000
0.018
0.087
0.105
0.264
0.483
0.173
0.329
0.005
0.000
0.000
0.040
0.048
0.159
0.119
0.014
0.133
0.001
0.000
0.000
0.000
0.000
0.044
0.231
0.145
0.005
0.000
0.000
0.000
0.000
0.000
0.057
0.269
0.236
0.134
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.018
0.087
0.082
0.109
0.035
0.008
0.000
0.000
0.000
0.000
0.032
0.024
0.024
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.018
0.027
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.023
0.042
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.007
0.019
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.002
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.003
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.001
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
Summary statistics for above PSHA PGA deaggregation,R=distance,e=epsilon:
Contribution from this GMPE(%):100.0
Mean sre-site R=87.3 km;M=5.85;epsO=0.32.Mean calculated for all sources.
Modal sye-site R=32.9 km;M=4.80;epsO=0.37 from peak (R,M)bin
MODE R*=35.7km;M*=4.80;EPS.INTERVAL:1 to 2 sigma %CONTRIB.=2.477
Principal sources
Source Category:
CEUS gridded
Individual fault
Fault ID
#*********End of
(faults,subduction,random seismicity having>3%contribution)
%contr.R(km) M epsilonO (mean values).
99.80 87.1 5.85 0.32
hazard details if its contribution to mean hazard>2%:
%contr.Rcd(km)M epsilonO Site-to-src azimuth (d)
deaggregation corresponding to Nean Hazard w/all m'iPEs *********#
EPS<-2
0.000
0.000
-2<EPS<-1
0.000
0.000
-l<EPS<D
0.000
0.000
P8HA Deaggregation.%contributions.site:Denison_White_M long:109.500 W.,lat:37.500 N.
Vs30(m/s)=760.0 (some WUS atten.models use Site Class not Vs30).
NSHMP 2007-08 See USGS OFR 2008-1128.dlol~0.2 below
Return period:2475 yrs.Exceedance PGA =0.07011 g.Weight *Computed_Rate_Ex D.I09E-G3
#Pr[at least one eq with median motion>=PGA in 50 yrs]=D.OG849
#This deaggregation corresponds to Toro et al.1997
DIST(KM)MAG(MW)ALL_EPS EPSILON>2 1<EPS<2 O<EPS<l
12.5 4.60 0.337 0.039 0.230 0.068
33.3 4.61 0.755 0.324 0.431 0.000
https://geohazards.usgs.gov/deaggint/2008/out/Denison_White_M_2012.05.25_15.24.10.txt 5/25/2012
Page 3 of 14
63.2 4.61 0.261 0.261 0.000 0.000 0.000 0.000 0.000
88.8 4.61 0.061 0.061 0.000 0.000 0.000 0.000 0.000
12.5 4.80 0.573 0.064 0.379 0.130 0.000 0.000 0.000
33.7 4.80 1.456 0.537 0.919 0.000 0.000 0.000 0.000
63.6 4.81 0.595 0.575 0.019 0.000 0.000 0.000 0.000
89.1 4.81 0.166 0.166 0.000 0.000 0.000 0.000 0.000
112.0 4.83 0.061 0.061 0.000 0.000 0.000 0.000 0.000
12.7 5.03 0.399 0.041 0.246 0.112 0.000 0.000 0.000
34.6 5.03 1.313 0.350 0.950 0.013 0.000 0.000 0.000
64.2 5.04 0.721 0.613 0.108 0.000 0.000 0.000 0.000
89.5 5.04 0.255 0.255 0.000 0.000 0.000 0.000 0.000
116.2 5.04 0.161 0.161 0.000 0.000 0.000 0.000 0.000
12.8 5.21 0.149 0.015 0.088 0.046 0.000 0.000 0.000
35.2 5.21 0.586 0.125 0.443 0.018 0.000 0.000 0.000
64.6 5.21 0.394 0.279 0.115 0.000 0.000 0.000 0.000
89.7 5.21 0.161 0.161 0.000 0.000 0.000 0.000 0.000
118.3 5.21 0.129 0.129 0.000 0.000 0.000 0.000 0.000
12.8 5.39 0.222 0.021 0.128 0.073 0.000 0.000 0.000
35.8 5.39 1.013 0.182 0.776 0.055 0.000 0.000 0.000
65.0 5.40 0.819 0.447 0.372 0.000 0.000 0.000 0.000
89.9 5.40 0.383 0.367 0.015 0.000 0.000 0.000 0.000
119.6 5.40 0.366 0.366 0.000 0.000 0.000 0.000 0.000
164.5 5.40 0.059 0.059 0.000 0.000 0.000 0.000 0.000
12.9 5.61 0.107 0.010 0.060 0.037 0.000 0.000 0.000
36.5 5.61 0.586 0.086 0.443 0.058 0.000 0.000 0.000
65.5 5.62 0.603 0.216 0.387 0.000 0.000 0.000 0.000
90.1 5.62 0.335 0.247 0.087 0.000 0.000 0.000 0.000
120.8 5.62 0.391 0.387 0.004 0.000 0.000 0.000 0.000
168.1 5.63 0.108 0.108 0.000 0.000 0.000 0.000 0.000
12.9 5.80 0.093 0.009 0.052 0.032 0.000 0.000 0.000
36.7 5.80 0.536 0.074 0.400 0.062 0.000 0.000 0.000
65.7 5.81 0.591 0.186 0.404 0.000 0.000 b.oOO 0.000
90.1 5.81 0.344 0.231 0.113 0.000 0.000 0.000 0.000
121.1 5.81 0.424 0.406 0.017 0.000 0.000 0.000 0.000
168.7 5.81 0.131 0.131 0.000 0.000 0.000 0.000 0.000
214.9 5.82 0.020 0.020 0.000 0.000 0.000 0.000 0.000
13 .5 6.01 0.079 0.007 0.044 0.028 0.000 0.000 0.000
37.1 6.01 0.390 0.046 0.270 0.074 0.000 0.000 0.000
60.1 6.01 0.387 0.072 0.312 0.003 0.000 0.000 0.000
84.7 6.01 0.556 0.197 0.359 0.000 0.000 0.000 0.000
121.9 6.01 0.552 0.440 0.112 0.000 0.000 0.000 0.000
170.6 6.01 0.215 0.215 0.000 0.000 0.000 0.000 0.000
218.2 6.02 0.057 0.057 0.000 0.000 0.000 0.000 0.000
16.5 6.19 0.119 0.011 0.066 0.042 0.000 0.000 0.000
37.9 6.22 0.336 0.038 0.227 0.070 0.000 0.000 0.000
60.3 6.21 0.387 0.066 0.315 0.006 0.000 0.000 0.000
84.6 6.21 0.559 0.173 0.386 0.000 0.000 0.000 0.000
122.0 6.22 0.590 0.429 0.161 0.000 0.000 0.000 0.000
170.9 6.22 0.244 0.244 0.000 0.000 0.000 0.000 0.000
219.0 6.22 0.070 0.070 0.000 0.000 0.000 0.000 0.000
14.0 6.42 0.057 0.005 0.031 0.021 0.000 0.000 0.000
37.3 6.42 0.263 0.027 0.161 0,074 0.000 0.000 0.000
64.8 6.43 0.410 0.061 0.325 0.025 0.000 0.000 0.000
87.8 6.41 0.378 0.084 0.294 0.000 0.000 0.000 0.000
122.8 6.42 0.634 0.304 0.331 0.000 0.000 0.000 0.000
171.6 6.42 0.324 0,299 0.025 0.000 0.000 0.000 0.000
220.0 6.42 0.122 0.122 0.000 0.000 0.000 0.000 0.000
269.1 6.43 0.030 0.030 0.000 0.000 0.000 0.000 0.000
12.9 6.59 0.032 0.003 0.018 0.012 0.000 0.000 0.000
37.6 6.59 0.164 0.017 0.099 0.048 0.000 0.000 0.000
62.9 6.60 0.206 0.027 0.158 0.021 0.000 0.000 0.000
86.8 6.59 0.273 0.056 0.216 0.000 0.000 0.000 0.000
123.4 6.60 0.403 0.170 0.233 0.000 0.000 0.000 0.000
171.9 6.60 0.220 0.185 0.035 0.000 0.000 0.000 0.000
https://geohazards.usgs.gov/deaggintI2008/outlDenison_White_M_2012.05.25_15.24.10.txt 512512012
Page 4 of 14
220.3 6.61 0.087 0.087 0.000 0.000 0.000 0.000 0.000
269.3 6.61 0.024 0.024 0.000 0.000 0.000 0.000 0.000
13.5 6.78 0.041 0.004 O.023 0.015 0.000 0.000 0.000
37.8 6.77 0.187 0.018 0.110 0.059 0.000 0.000 0.000
60.6 6.78 0.223 O.027 0.161 0.036 0.000 0.000 0.000
85.0 6.78 0.380 0.065 0.308 0.007 0.000 0.000 0.000
123.4 6.78 0.549 0.189 0.360 0.000 0.000 0.000 0.000
172 .4 6.78 0.311 0.239 O. 072 0.000 0.000 0.000 0.000
220.7 6.78 0.131 0.130 0.001 0.000 0.000 0.000 0.000
270.0 6.78 0.038 O.038 0.000 0.000 0.000 0.000 0.000
38.6 6.97 0.061 0.006 0.035 0.021 0.000 0.000 0.000
61.7 6.97 0.066 0.007 0.042 0.017 0.000 0.000 0.000
85.6 6.97 0.132 0.018 0.102 0.012 0.000 0.000 0.000
123.6 6.97 0.220 0.049 0.171 0.000 0.000 0.000 0.000
172.6 6.96 0.152 0.072 0.080 0.000 0.000 0.000 0.000
221.5 6.96 0.070 0.062 0.008 0.000 0.000 0.000 0.000
271.0 6.96 0.025 0.025 0.000 0.000 0.000 0.000 0.000
65.7 7.16 0.024 0.003 0.016 0.005 0.000 0.000 0.000
90.1 7.16 0.022 0.003 0.018 0.000 0.000 0.000 0.000
124.3 7.16 0.044 0.011 0.033 0.000 0.000 0.000 0.000
172.9 7.16 0.028 0.016 0.013 0.000 0.000 0.000 0.000
Summary statistics for above PSHA PGA deaggregation,Re dda tance,e=epsilon:
Contribution from this GMPE(%):26.7
Mean sre-site R=76.9 km;M=5.72;epsO>0.46.Mean calculated for all sources.
Modal sre-site R=33.7 km;M=4.80;epsO:::0.49 from peak (R,M)bin
MODE R*=33.4km;M*=5.03;EPS.INTERVAL:1 to 2 sigma %CONTRIB.=0.950
Principal sources
Source Category:
CEUS gridded
Individual fault
Fault ID
#*********End of
(faults,subduction,random seismicity having>3%contribution)
%contr.R(km)M epsilonO (mean values).
26.68 76.9 5.72 0.46
hazard details if its contribution to mean hazard>2%:
%contr.Rcd(km)M epsilonO Site-to-src azimuth{d)
deaggregation corresponding to Toro et al.1997 *********#
EPS<-2
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
-2<EPS<-1
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
PSHA Deaggregation.%contributions.site:Denison_White_M long:109.500 W.,lat:37.500 N.
Vs30(m/s)=760.0 (some was atten.models use Site Class not Vs30).
NSHMP 2007-08 See USGS OFR 2008-1128.dM=0.2 below
Return period:2475 yrs.Exceedance PGA =0.07011 g.Weight *Computed_Rate_Ex 0.109E-04
#Pr[at least one eq with median motion>=PGA in 50 yrs}=0.00171
#This deaggregation corresponds to Atkinson-Boore06,140 bar
DIST(KM)MAG(MW)ALL_EPS EPSILON>2 1<EPS<2 O<EPS<l -l<EPS<O
11.6 4.61 0.084 0.041 0.043 0.000 0.000
12.9 4.80 0.192 0.088 0.104 0.000 0.000
33.8 4.82 0.002 0.002 0.000 0.000 0.000
14.6 5.03 0.177 0.081 0.096 0.000 0.000
35.7 5.05 0.008 0.008 0.000 0.000 0.000
15.9 5.21 0.081 0.037 0.044 0.000 0.000
37.0 5.21 0.007 0.007 0.000 0.000 0.000
15.1 5.38 0.118 0.043 0.076 0.000 0.000
30.8 5.44 0.051 0.042 0.009 0.000 0.000
55.4 5.43 0.002 0.002 0.000 0.000 0.000
12.5 5.61 0.047 0.010 0.037 0.000 0.000
30.2 5.62 0.062 0.044 0.019 0.000 0.000
57.7 5.62 0.004 0.004 0.000 0.000 0.000
85.8 5.65 0.001 0.001 0.000 0.000 0.000
120.8 5.67 0.002 0.002 0.000 0.000 0.000
12.6 5.80 0.043 0.009 0.034 0.000 0.000
31.4 5.81 0.079 0.049 0.030 0.000 0.000
58.3 5.82 0.009 0.009 0.000 0.000 0.000
86.3 5.82 0.008 0.008 0.000 0.000 0.000
124.3 5.78 0.007 0.007 0.000 0.000 0.000
125.1 5.87 0.008 0.008 0.000 0.000 0.000
157.1 5.85 0.002 0.002 0.000 0.000 0.000
https://geohazards.usgs.gov/deaggint/2008/outlDenison_White_M_2012.05.25_15.24.10.txt 5/2512012
Page 5 of 14
13.3 6.01 0.037 0.007 0.030 0.000 0.000 0.000 0.000
33.3 6.01 0.069 0.040 0.029 0.000 0.000 0.000 0.000
57.9 6.02 0.015 0.015 0.000 0.000 0.000 0.000 0.000
86.2 6.02 0.014 0.014 0.000 0.000 0.000 0.000 0.000
125.4 6.02 0.031 0.031 0.000 0.000 0.000 0.000 0.000
164.6 6.02 0.009 0.009 0.000 0.000 0.000 0.000 0.000
16.0 6.20 0.054 0.011 0.043 0.000 0.000 0.000 0.000
35.1 6.23 0.074 0.037 0.036 0.000 0.000 0.000 0.000
58.6 6.22 0.026 O.026 0.000 0.000 0.000 0.000 0.000
86.1 6.22 0.029 0.029 0.000 0.000 0.000 0.000 0.000
125.6 6.22 0.066 0.066 0.000 0.000 0.000 0.000 0.000
168.8 6.23 0.030 0.030 0.000 0.000 0.000 0.000 0.000
211.9 6.25 0.003 0.003 0.000 0.000 0.000 0.000 0.000
13.9 6.42 0.028 0.005 0.022 0.000 0.000 0.000 0.000
34.5 6.42 0.070 0.027 0.043 0.000 0.000 0.000 0.000
59.3 6.42 0.026 0.026 0.000 0.000 0.000 0.000 0.000
85.8 6.43 0.035 0.035 0.000 0.000 0.000 0.000 0.000
125.8 6.43 O.083 O.083 0.000 0.000 0.000 0.000 0.000
170.3 6.43 0.046 0.046 0.000 0.000 0.000 0.000 0.000
217.7 6.43 0.012 0.012 0.000 0.000 0.000 0.000 0.000
12.9 6.59 0.016 0.003 0.013 0.000 0.000 0.000 0.000
35.3 6.59 0.050 0.017 0.033 0.000 0.000 0.000 0.000
61.2 6.60 0.024 0.022 O.002 0.000 0.000 0.000 0.000
87.6 6.59 0.029 0.029 0.000 0.000 0.000 0.000 0.000
126.3 6.59 0.075 0.075 0.000 0.000 0.000 0.000 0.000
171.2 6.59 0.047 0.047 0.000 0.000 0.000 0.000 0.000
219.4 6.59 0.015 0.015 0.000 0.000 0.000 0.000 0.000
266.3 6.60 0.003 0.003 0.000 0.000 0.000 0.000 0.000
13.5 6.78 0.020 0.004 O.017 0.000 0.000 0.000 0.000
35.9 6.77 0.063 0.018 0.045 0.000 0.000 0.000 0.000
59.5 6.78 0.037 0.026 0.010 0.000 0.000 0.000 0.000
85.9 6.78 0.052 0.052 0.000 0.000 0.000 0.000 0.000
126.2 6.78 0.130 0.130 0.000 0.000 0.000 0.000 0.000
172.1 6.78 0.089 0.089 0.000 0.000 0.000 0.000 0.000
220.4 6.79 0.035 0.035 0.000 0.000 0.000 0.000 0.000
269.6 6.79 0.009 0.009 0.000 0.000 O.000 0.000 0.000
318.5 6.81 O.002 0.002 0.000 0.000 0.000 0.000 0.000
13.9 6.97 0.007 0.001 0.005 0.000 0.000 0.000 0.000
37.1 6.97 0.022 0.006 0.016 0.000 0.000 0.000 0.000
60.8 6.97 0.012 0.007 0.005 0.000 0.000 0.000 0.000
86.2 6.97 0.021 0.018 0.003 0.000 0.000 0.000 0.000
125.6 6.97 0.050 0.047 0.003 0.000 0.000 0.000 0.000
172.1 6.97 0.038 0.038 0.000 0.000 0.000 0.000 0.000
221.1 6.97 0.016 0.016 0.000 0.000 0.000 0.000 0.000
270.7 6.98 0.005 0.005 0.000 0.000 0.000 0.000 0.000
330.3 6.99 O.002 0.002 0.000 0.000 0.000 0.000 0.000
19.3 7.16 0.003 0.001 0.002 0.000 0.000 0.000 0.000
40.7 7.16 0.004 0.001 0.003 0.000 0.000 0.000 0.000
64.6 7.16 0.005 0.003 0.003 0.000 0.000 0.000 0.000
90.4 7.16 0.005 0.003 O.002 0.000 0.000 0.000 0.000
126.6 7.16 0.015 0.011 0.004 0.000 0.000 0.000 0.000
173.3 7.16 O.012 0.012 0.000 0.000 0.000 0.000 0.000
221.2 7.16 0.006 0.006 0.000 0.000 0.000 0.000 0.000
271.4 7.16 0.002 0.002 0.000 0.000 0.000 0.000 0.000
341.5 7.16 0.001 0.001 0.000 0.000 0.000 0.000 0.000
Summary statistics for above PSHA PGA deaggregation,R=distance,e:=:epsilon:
Contribution from this GMPE(%):2.7
Mean sre-site R=70.9 km;M=6.05;epsO=0.51.Mean calculated for all sources.
Modal sre-site R=12.9 km;M=4.80;epsO=-0.06 from peak (R,M)bin
MODE R*=126.2km;W=6.78;EPS.INTERVAL:1 to 2 sigma %CONTRIB.=0.130
Principal sources (faults,subduction,random seismicity having>3%contribution)
Source Category:%contr.R(km)M epsilonO (mean values).
https://geohazards.usgs.gov/deaggint/2008/out/Denison_White_M_2012.05.25_15.24.10.txt 5/25/2012
Individual fault
Fault ID
#*********End of
Page 6 of 14
hazard details if its contribution to mean hazard>2%:
%contr.Rcd(km)M epsilonO Site-to-src azimuth (d)
deaggregation corresponding to Atkinson-Boore06,140 bar *********#
PSHA Deaggregation.%contributions.site:Denison_White_M long:109.500 W.,lat:37.500 N.
Vs30(m/s)=760.0 (some was atten.models use Site Class not Vs30).
NSHMP 2007-08 See USGS OFR 2008-1128.dM=0.2 below
Return period:2475 yrs.Exceedance PGA =0.07011 g.Weight *Computed_Rate_Ex 0.882E-04
#Pr[at least one eq with median motion>=PGA in 50 yrs]=0.01364
#This deaggregation corresponds to
DIST (K~l)
12.6
32.4
62.4
89.3
12.7
33.4
63.2
89.8
115.6
12.8
34.6
64.0
90.2
119.7
158.4
12.9
35.3
64.6
90.3
121.a
163.6
12.9
36.0
65.1
90.4
122.1
167.7
12.9
36.6
64.6
88.6
122.9
169.3
215.7
12.9
37.1
60.4
85.5
123.4
170.2
218.7
13.6
37.2
60.1
85.6
123.9
171.7
219.9
267.6
16.6
38.2
60.4
85.7
HAG(MW)
4.60
4.61
4.61
4.62
4.79
4.80
4.81
4.81
4.82
5.03
5.03
5.04
5.04
5.04
5.07
5.21
5.21
5.21
5.21
5.21
5.21
5.39
5.40
5.40
5.40
5.41
5.41
5.61
5.61
5.61
5.63
5.62
5.62
5.63
5.80
5.80
5.81
5.81
5.81
5.81
5.82
6.01
6.01
6.01
6.01
6.01
6.01
6.01
6.02
6.19
6.22
6.21
6.21
ALL_EPS
0.183
0.393
0.081
0.019
0.318
0.900
0.281
0.096
0.072
0.215
0.796
0.379
0.167
0.196
0.015
0.078
0.349
0.218
0.112
0.154
0.029
0.115
0.598
0.470
0.282
0.455
0.139
0.055
0.327
0.298
0.266
0.425
0.170
0.033
0.047
0.312
0.233
0.444
0.596
0.290
0.083
0.040
0.211
0.217
0.372
0.601
0.326
0.116
0.026
0.061
0.185
0.233
0.423
EPSILON>2
0.039
0.248
0.081
0.019
0.064
0.498
0.281
0.096
0.072
0.041
0.350
0.377
0.167
0.196
0.015
0.015
0.125
0.208
0.112
0.154
O.029
O.021
0.182
0.396
0.282
0.455
0.139
0.010
0.086
0.191
0.254
0.425
0.170
O.033
0.009
0.074
0.098
0.325
0.589
0.290
0.083
0.007
0.046
0.072
0.197
0.517
0.326
0.116
0.026
0.011
0.038
0.066
0.173
Frankel et al.,1996
1<EPS<2 O<EPS<l -l<EPS<O
0.144 0.000 0.000
0.145 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.254 0.000 0.000
0.402 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.173 0.000 0.000
0.446 0.000 0.000
0.002 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.064 0.000 0.000
0.224 0.000 0.000
0.010 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.094 0.000 0.000
0.416 0.000 0.000
0.074 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.045 0.000 0.000
0.242 0.000 0.000
0.107 0.000 0.000
0.012 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.039 0.000 0.000
0.239 0.000 0.000
0.135 0.000 0.000
0.119 0.000 0.000
0.007 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.033 0.000 0.000
0.165 0.000 0.000
0.145 0.000 0.000
0.176 0.000 0.000
0.083 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.050 0.000 0.000
0.147 0.000 0.000
0.166 0.000 0.000
0.250 0.000 0.000
-2<EPS<-1
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
o.00a.
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
EPS<-2
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
https://geohazards.usgs.gov/deaggint/2008/outlDenison_White_M_2012.05.25_15.24.10.txt 5/25/2012
124.4
172.3
220.7
269.3
14.0
37.4
60.7
85.5
124.8
125.1
172.7
221.0
270.6
333.4
13.0
37.8
62.8
87.3
125.7
173.3
221.6
270.8
341.2
13.5
38.0
60.8
85.7
125.6
173.9
222.1
271.4
347.4
352.8
38.7
61.7
86.1
125.3
173.9
222.5
272 .0
356.7
66.0
90.4
126.4
174.8
222.5
272 .5
361.0
6.21
6.22
6.22
6.22
6.42
6.42
6.42
6.42
6.40
6.49
6.42
6.43
6.43
6.43
6.59
6.59
6.60
6.59
6.59
6.59
6.59
6.59
6.59
6.78
6.77
6.78
6.78
6.78
6.78
6.78
6.78
6.74
6.86
6.97
6.97
6.97
6.97
6.97
6.97
6.97
6.98
7.16
7.16
7.16
7.16
7.16
7.16
7.16
0.768
0.496
0.206
0.060
0.029
0.138
0.159
0.319
0.470
0.168
0.472
0.231
0.077
0.032
0.016
0.086
0.114
0.191
0.429
0.356
0.192
0.074
0.041
0.021 .
0.097
0.125
0.254
0.569
0.505
0.305
0.128
0.057
0.036
0.031
0.034
0.076
0.171
0.168
0.103
0.049
0.044
0.013
0.015
0.043
0.045
0.031
0.016
0.017
0.503
0.491
0.206
0.060
0.005
0.027
0.040
0.106
0.234
0.074
0.418
0.231
0.077
0.032
0.003
0.017
0.027
0.056
0.170
0.259
0.192
0.074
0.041
0.004
0.018
0.027
0.065
0.189
0.279
0.282
0.128
0.057
0.036
0.006
0.007
0.018
0.049
0.073
0.077
0.049
0.044
0.003
0.003
0.011
0.016
0.017
0.014
0.017
0.264
0.004
0.000
0.000
0.023
0.111
0.119
0.213
0.236
0.093
0.054
0.000
0.000
0.000
0.013
0.070
0.087
0.135
0.259
0.097
0.000
0.000
0.000
0.017
0.079
0.098
0.189
0.380
0.226
0.022
0.000
0.000
0.000
0.025
0.027
0.058
0.123
0.095
0.025
0.000
0.000
0.011
0.011
0.032
0.029
0.014
0.001
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0 ..000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
Page 7 of 14
Summary statistics for above PSHA PGA deaggregation,R=distance,e=epsilon:
Contribution from this GMPE(%):21.6
Mean sre-site R=104.6 km;M=5.87;epsO=0.43.Mean calculated for all sources.
Modal src-site R=33.4 km;M=4.80;epsO=0.27 from peak (R,M)bin
MODE R*=123.4km;M*=5.81;EPS.INTERVAL:1 to 2 sigma %CONTRIB.=0.589
Principal sources
Source Category:
CEUS gridded
Individual fault
Fault ID
#*********End of
(faults,subduction,random seismicity having>3%contribution)
%contr.R(km)M epsilonO (mean values).
21.64 104.5 5.87 0.43
hazard details if its contribution to mean hazard>2%:
%contr.Rcd(km)M epsilonO Site-to-src azimuth(d)
deaggregation corresponding to Frankel et al.,1996 *********#
PSHA Deaggregation.%contributions.site:DenisOll_vfuite_M long:109.500 W.,lat:37.500 N.
Vs30(m/s)=760.0 (some WUS atten.models use Site Class not Vs30).
https://geohazards.usgs.gov/deaggint!2008/outlDenison_White_M_2012.05.25_15.24.10.txt 5/25/2012
Page 8 of 14
NSHMP 2007-08 See USGS OFR 2008-1128.clM=0.2 below
Return period:2475 yrs.Exceedance PGA =0.07011 g.Weight *Computed_Rate_Ex 0.668E-04
#Pr[at least one eq with median motion>=PGA in 50 yrsJ=0.01452
#This deaggregation corresponds to Campbell CEUS Hybrid
DIST(KM)MAG (1111)ALL_EPS EPSILON>2 1<EPS<2 O<EPS<l -l<EPS<O -2<EPS<-1 EPS<-2
12.8 4.60 0.202 0.039 0.163 0.000 0.000 0.000 0.000
31.8 4.60 0.468 0.255 0.212 0.000 0.000 0.000 0.000
61.1 4.61 0.064 0.064 0.000 0.000 0.000 0.000 0.000
89.6 4.62 0.015 0.015 0.000 0.000 0.000 0.000 0.000
12.8 4.79 0.341 0.064 0.277 0.000 0.000 0.000 0.000
32.8 4.80 1.008 0.492 0.517 0.000 0.000 0.000 0.000
61.8 4.80 0.196 0.196 0.000 0.000 0.000 0.000 0.000
90.0 4.81 0.061 0.061 0.000 0.000 0.000 0.000 0.000
115.3 4.82 0.051 0.051 0.000 0.000 0.000 0.000 0.000
12.9 5.03 0.224 0.041 0.182 0.000 0.000 0.000 0.000
33.9 5.03 0.863 0.350 0.512 0.000 0.000 0.000 0.000
62.6 5.04 0.248 0.248 0.000 0.000 0.000 0.000 0.000
90.2 5.04 0.096 0.096 0.000 0.000 0.000 0.000 0.000
119.1 5.04 0.115 0.115 0.000 0.000 0.000 0.000 0.000
12.9 5.21 0.081 0.015 0.066 0.000 0.000 0.000 0.000
34.8 5.21 0.374 0.125 0.249 0.000 0.000 0.000 0.000
63.1 5.21 0.144 0.139 0.004 0.000 0.000 0.000 0.000
90.3 5.21 0.064 0.064 0.000 0.000 0.000 0.000 0.000
120.4 5.21 0.088 0.088 0.000 0.000 0.000 0.000 0.000
12.9 5.39 0.117 0.021 0.096 0.000 0.000 0.000 0.000
35.6 5.40 0.634 0.182 0.452 0.000 0.000 0.000 0.000
61.7 5.39 0.275 0.240 0.035 0.000 0.000 0.000 0.000
87.0 5.42 0.210 0.210 0.000 0.000 0.000 0.000 0.000
121.2 5.41 0.251 0.251 0.000 0.000 0.000 0.000 0.000
160.4 5.42 0.030 0.030 0.000 0.000 0.000 0.000 0.000
12.9 5.61 0.055 0.010 0.045 0.000 0.000 0.000 0.000
36.5 5.61 0.349 0.086 0.264 0.000 0.000 0.000 0.000
59.6 5.62 0.170 0.111 0.058 0.000 0.000 0.000 0.000
85.2 5.62 0.215 0.215 0.000 0.000 0.000 0.000 0.000
122.0 5.62 0.241 0.241 0.000 0.000 0.000 0.000 0.000
164.3 5.62 0.045 0.045 0.000 0.000 0.000 0.000 0.000
12.9 5.80 0.048 0.009 0.039 0.000 0.000 0.000 0.000
37.1 5.80 0.334 0.074 0.260 0.000 0.000 0.000 0.000
59.8 5.81 0.202 0.098 0.104 0.000 0.000 0.000 0.000
85.4 5.81 0.295 0.281 0.014 0.000 0.000 0.000 0.000
122.5 5.81 0.366 0.366 0.000 0.000 0.000 0.000 0.000
166.3 5.81 0.090 0.090 0.000 0.000 0.000 0.000 0.000
13.6 6.01 0.040 0.007 0.033 0.000 0.000 0.000 0.000
37.3 6.01 0.226 0.046 0.181 0.000 0.000 0.000 0.000
59.5 6.01 0.203 0.072 0.131 0.000 0.000 0.000 0.000
85.5 6.01 0.277 0.197 0.080 0.000 0.000 0.000 0.000
122.9 6.01 0.404 0.396 0.008 0.000 0.000 0.000 0.000
168.1 6.01 0.115 0.115 0.000 0.000 0.000 0.000 0.000
212.0 6.02 0.011 0.011 0.000 0.000 0.000 0.000 0.000
16.6 6.19 0.061 0.011 0.050 0.000 0.000 0.000 0.000
38.4 6.22 0.198 0.038 0.160 0.000 0.000 0.000 0.000
60.0 6.21 0.231 0.066 0.165 0.000 0.000 0.000 0.000
85.5 6.22 0.356 0.173 0.183 0.000 0.000 0.000 0.000
123.3 6.22 0.579 0.460 0.118 0.000 0.000 0.000 0.000
168.9 6.22 0.202 0.202 0.000 0.000 0.000 0.000 0.000
215.8 6.23 0.030 0.030 0.000 0.000 0.000 0.000 0.000
14.0 6.42 0.029 0.005 0.023 0.000 0.000 0.000 0.000
37.7 6.42 0.145 0.027 0.118 0.000 0.000 0.000 0.000
60.5 6.42 0.166 0.040 0.126 0.000 0.000 0.000 0.000
85.4 6.42 0.301 0.106 0.195 0.000 0.000 0.000 0.000
123.9 6.42 0.545 0.308 0.237 0.000 0.000 0.000 0.000
169.6 6.43 0.231 0.230 0.001 0.000 0.000 0.000 0.000
217.1 6.43 0.047 0.047 0.000 0.000 0.000 0.000 0.000
13.0 6.59 0.016 0.003 0.013 0.000 0.000 0.000 0.000
https:llgeohazards.usgs.gov/deaggilltI2008/outIDenison_White_M_2012.05.25_15.24.10.txt 512512012
Page 9 of 14
38.0
62.7
87.3
124.8
170.4
217.9
13.5
38.2
60.7
85.8
124.8
125.6
171.4
218.7
267.3
38.8
61.7
86.2
124.8
125.3
171.7
219.6
268.2
66.1
90.5
126.4
173.2
.219.9
6.59
6.60
6.59
6.59
6.59
6.59
6.78
6.77
6.78
6.78
6.74
6.86
6.78
6.79
6.79
6.97
6.97
6.97
6.92
7.03
6.97
6.97
6.98
7.16
7.16
7.16
7.16
7.16
0.090
0.121
0.193
0.404
0.203
0.049
0.021
0.100
0.135
0.270
0.394
0.191
0.343
0.101
0.016
0.032
0.037
0.083
0.109
0.080
0.136
0.044
0.009
0.014
0.016
0.049
0.042
0.017
0.017
0.027
0.056
0.170
0.185
0.049
0.004
0.018
O. 027·
0.065
0.133
0.055
0.253
0.101
0.016
0.006
0.007
0.018
O.029
0.019
O.073
0.044
0.009
0.003
0.003
0.011
0.016
0.015
0.074
0.095
0.137
0.234
0.017
0.000
O.017
0.082
0.108
0.205
0.260
0.136
0.090
0.000
0.000
0.026
0.030
0.065
0.080
0.060
0.063
0.001
0.000
O. 012
O.013
0.038
0.026
0.003
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.02.Mean calculated for all
0.05 from peak (R,M)bin
to 2 sigma %CONTRIB.=0.517
Summary statistics for above PSHA PGA deaggregation,
Contribution from this GMPE(%):16.4
Mean sre-site R~81.2 km;M=5.81;epsO=
Modal sre-site R=32.8 krn;M=4.80;epsO=
MODE R*=28.6km;M*=4.80;EPS.INTERVAL:1
R=distance,e=epsilon:
sources.
principal sources
Source Category:
CEUS gridded
Individual fault
Fault In
#*********End of
(faults,subduction,random seismicity having>3%contribution)
%contr.R(km) M epsilonO (mean values).
16.39 81.2 5.81 0.02
hazard details if its contribution to mean hazard>2%:
%contr.Rcd(km)M epsilonO Site-to-src azimuth(d}
deaggregation corresponding to Campbell CEUS Hybrid *********#
EPS<-2
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
-2<EPS<-1
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
-l<EPS<O
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
PSHA Deaggregation.%contributions.site:Denison_White_M long:109.500 W.,lat:37.500 N.
Vs30(m/s)=760.0 (some wus atten.models use Site Class not Vs30).
NSHMP 2007-08 See USGS OFR 2008-1128.dM=0.2 below
Return period:2475 yrs.Exceedance PGA =0.07011 g.Weight *Computed_Rate_Ex 0.540E-04
#Pr(at least one eq with median motion>=PGA in 50 yrs]=0.00790
#This deaggregation corresponds to Silva i-corner
DIST(KM)MAG(MW)ALL_EPS EPSILON>2 1<EPS<2 O<EPS<l
12.3 4.60 0.148 0.039 0.109 0.000
32.7 4.61 0.290 0.221 0.069 0.000
62.1 4.61 0.071 0.071 0.000 0.000
86.6 4.62 0.007 0.007 0.000 0.000
12.5 4.80 0.268 0.064 0.204 0.000
33.6 4.80 0.665 0.451 0.214 0.000
63.0 4.81 0.230 0.230 0.000 0.000
88.5 4.81 0.045 0.045 0.000 0.000
12.6 5.03 0.188 0.041 0.147 0.000
34.5 5.03 0.601 0.342 0.260 0.000
63.8 5.04 0.296 0.296 0.000 0.000
89.2 5.04 0.086 0.086 0.000 0.000
111.5 5.05 0.033 0.033 0.000 0.000
12.7 5.21 0.071 0.015 0.056 0.000
35.2 5.21 0.270 0.125 0.145 0.000
https:llgeohazards.usgs.gov/deaggintI2008/outIDenison_White_M_2012.05.25_15.24.10.txt 512512012
Page 10 of 14
64.3 5.21 0.169 0.168 0.001 0.000 0.000 0.000 0.000
89.5 5.21 0.061 0.061 0.000 0.000 0.000 0.000 0.000
115.6 5.21 0.036 0.036 0.000 0.000 0.000 0.000 0.000
12.8 5.39 0.107 0.021 0.085 0.000 0.000 0.000 0.000
35.7 5.40 0.471 0.182 0.290 0.000 0.000 0.000 0.000
64.8 5.40 0.366 0.337 0.029 0.000 0.000 0.000 0.000
89.7 5.40 0.158 0.158 0.000 0.000 0.000 0.000 0.000
118.3 5.41 0.i29 0.129 0.000 0.000 0.000 0.000 0.000
159.4 5.44 0.010 0.010 0.000 0.000 0.000 0.000 0.000
12.8 5.61 O.052 0.010 0.042 0.000 0.000 0.000 0.000
36.3 5.61 0.268 0.086 0.182 0.000 0.000 0.000 0.000
65.3 5.62 0.261 0.203 O.058 0.000 0.000 0.000 0.000
90.0 5.62 0.136 0.136 0.000 0.000 0.000 0.000 0.000
120.0 5.62 0.140 0.140 0.000 0.000 o.obo 0.000 0.000
166.0 5.63 0.029 O.029 0.000 0.000 0.000 0.000 0.000
12.9 5.80 0.046 0.009 0.037 0.000 0.000 0.000 0.000
36.8 5.80 0.263 0.074 0.189 0.000 0.000 0.000 0.000
65.8 5.81 0.303 0.186 0.117 0.000 0.000 0.000 0.000
90.2 5.81 0.182 0.180 0.002 0.000 0.000 0.000 0.000
121.1 5.81 0.224 0.224 0.000 0.000 0.000 0.000 0.000
168.8 5.82 0.069 0.069 0.000 0.000 0.000 0.000 0.000
213.3 5.83 0.010 0.010 0.000 0.000 0.000 0.000 0.000
13.5 6.01 0.039 0.007 0.032 0.000 0.000 0.000 0.000
37.0 6.01 0.184 0.046 0.138 0.000 0.000 0.000 0.000
61.9 6.00 0.207 0.088 0.119 0.000 0.000 0.000 0.000
85.7 6.02 0.233 0.177 0.056 0.000 0.000 0.000 0.000
121.8 6.01 0.254 0.254 0.000 0.000 0.000 0.000 0.000
170.8 6.01 0.097 0.097 0.000 0.000 0.000 0.000 0.000
218.5 6.02 O.027 0.027 0.000 0.000 0.000 0.000 0.000
16.5 6.20 0.059 O.all 0.048 0.000 0.000 0.000 0.000
38.0 6.22 0.166 0.038 0.128 0.000 0.000 0.000 0.000
60.4 6.21 0.201 0.066 0.134 0.000 0.000 0.000 0.000
84.9 6.21 0.311 0.173 0.138 0.000 0.000 0.000 0.000
122 .5 6.22 0.365 0.350 0.015 0.000 0.000 0.000 0.000
171.6 6.22 0.174 0.174 0.000 0.000 0.000 0.000 0.000
220.2 6.22 0.063 0.063 0.000 0.000 0.000 0.000 0.000
268.6 6.23 0.016 0.016 0.000 0.000 0.000 0.000 0.000
13.9 6.42 0.028 0.005 O.023 0.000 0.000 0.000 0.000
37.2 6.42 0.127 0.027 0.100 0.000 0.000 0.000 0.000
65.1 6.43 0.203 0.061 0.142 0.000 0.000 0.000 0.000
88.1 6.41 0.187 0.084 0.102 0.000 0.000 0.000 0.000
123.2 6.42 0.340 0.281 0.059 0.000 0.000 0.000 0.000
172.1 6.42 0.194 0.194 0.000 0.000 0.000 0.000 0.000
220.8 6.43 0.087 0.087 0.000 0.000 0.000 0.000 0.000
270.7 6.43 0.029 O.029 0.000 0.000 0.000 0.000 0.000
331.5 6.45 0.010 0.010 0.000 0.000 0.000 0.000 0.000
12.9 6.59 0.016 0.003 0.013 0.000 0.000 0.000 0.000
37.6 6.59 0.081 0.017 0.064 0.000 0.000 0.000 0.000
62.7 6.60 0.103 0.027 0.076 0.000 0.000 0.000 0.000
86.8 6.59 0.153 0.056 0.097 0.000 0.000 0.000 0.000
124.2 6.59 0.250 0.170 0.080 0.000 0.000 0.000 0.000
172.8 6.59 0.165 0.165 0.000 0.000 0.000 0.000 0.000
221.4 6.59 0.082 0.082 0.000 0.000 0.000 0.000 0.000
271.0 6.59 0.032 0.032 0.000 0.000 0.000 0.000 0.000
343.6 6.60 0.020 0.020 0.000 0.000 0.000 0.000 0.000
13.5 6.78 0.021 0.004 0.017 0.000 0.000 0.000 0.000
37.8 6.77 0.093 0.018 0.074 0.000 0.000 0.000 0.000
60.7 6.78 0.115 0.027 O.088 0.000 0.000 0.000 0.000
85.3 6.78 0.213 0.065 0.148 0.000 0.000 0.000 0.000
124.3 6.78 0.365 0.189 0.176 0.000 0.000 0.000 0.000
173.5 6.78 0.265 0.244 0.021 0.000 0.000 0.000 0.000
222.0 6.78 0.150 0.150 0.000 0.000 0.000 0.000 0.000
271.8 6.79 0.064 0.064 0.000 0.000 0.000 0.000 0.000
357.5 6.79 0.059 0.059 0.000 0.000 0.000 0.000 0.000
https://geohazards.usgs.gov/deaggint/2008/outlDenison_White_M_2012.05.25_15.24.10.txt 5/25/2012
Page 11 of 14
38.6 6.97 0.030 0.006 0.024 0.000 0.000 0.000 0.000
61.7 6.97 0.032 0.007 0.025 0.000 0.000 0.000 0.000
85.7 6.97 0.066 0.018 0.048 0.000 0.000 0.000 0.000
124.2 6.97 0.120 0.049 0.071 0.000 0.000 0.000 0.000
173.5 6.97 0.099 0.072 0.027 0.000 0.000 0.000 0.000
222.5 6.97 0.058 0.057 0.000 0.000 0.000 0.000 0.000
272 .3 6.97 0.028 0.028 0.000 0.000 0.000 0.000 0.000
366.1 6.98 0.033 0.033 0.000 0.000 0.000 0.000 0.000
65.9 7.16 0.013 0.003 0.010 0.000 0.000 0.000 0.000
90.3 7.16 0.013 0.003 0.010 0.000 0.000 0.000 0.000
125.6 7.16 0.032 0.011 0.021 0.000 0.000 0.000 0.000
174.4 7.16 0.029 0.016 0.013 0.000 0.000 0.000 0.000
222.5 7.16 0.019 0.017 0.003 0.000 0.000 0.000 0.000
272.8 7.16 0.010 0.010 0.000 0.000 0.000 0.000 0.000
370.3 7.16 0.014 0.014 0.000 0.000 0.000 0.000 0.000
Summary statistics for above PSHA PGA deaggregation,R=distance,e=epsilon:
Contribution from this GMPE(%):13.2
Mean sre-site R=87.2 km;M=5.84;epsO=0.52.Mean calculated for all sources.
jrodaL sre-site R=33.6 km;M=4.80;epsO=0.58 from peak (R,M)bin
MODE R*=36.5km;M*=4.80;EPS.INTERVAL:1 to 2 sigma %CONTRIB.=0.451
Principal sources
Source Category:
CEUS gridded
Individual fault
Fault ID
#*********End of
(faults,subduction,random seismicity having>3%contribution)
%contr.R(km) M epsilonO (mean values).
13.24 86.9 5.84 0.52
hazard details if its contribution to mean hazard>2%:
%contr.Rcd(krn)M epsilonO Site-to-src azimuth(d)
deaggregation corresponding to Silva 1-corner *********#
EPS<-2
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
-2<EPS<-1
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
PSHA Deaggregation.%contributions.site:nenison_White_M long:109.500 W.,lat:37.500 N.
Vs30(m/s)=760.0 (some WUS atten.models use Site Class not Vs30).
NSHMP 2007-08 See USGS OFR 2008-1128.dM=0.2 below
Return period:2475 yrs.Exceedance PGA =0.07011 g.Weight *Computed_Rate_Ex O.605E-04
#Pr[at least one eq with median motion>=PGA in 50 yrs]=0.01408
#This deaggregation corresponds to Tavakoli and Pezeshk 05
nIST(KM)MAG (MW)ALL_EPS EPSILON>2 1<EPS<2 O<EPS<l -l<EPS<O
12.5 4.60 0.183 0.039 0.145 0.000 0.000
29.5 4.61 0.222 0.153 0.069 0.000 0.000
12.7 4.79 0.325 0.064 0.262 0.000 0.000
30.7 4.80 0.596 0.347 0.249 0.000 0.000
59.3 4.81 0.044 0.044 0.000 0.000 0.000
12.8 5.03 0.220 0.041 0.179 0.000 0.000
32.4 5.03 0.621 0.301 0.320 0.000 0.000
61.2 5.04 0.094 0.094 0.000 0.000 0.000
90.1 5.05 0.027 0.027 0.000 0.000 0.000
115.4 5.06 0.023 0.023 0.000 0.000 0.000
12.9 5.21 0.080 0.015 0.065 0.000 0.000
33.6 5.21 0.302 0.125 0.177 0.000 0.000
62.1 5.21 0.071 0.071 0.000 0.000 0.000
90.3 5.21 0.027 0.027 0.000 0.000 0.000
119.4 5.21 0.035 0.035 0.000 0.000 0.000
12.9 5.39 0.117 0.021 0.096 0.000 0.000
34.8 5.46 0.557 0.182 0.375 0.000 0.000
58.9 5.40 0.152 0.145 0.007 0.000 0.000
85.1 5.41 0.142 0.142 0.000 0.000 0.000
121.2 5.41 0.148 0.148 0.000 0.000 0.000
158.7 5.43 0.014 0.014 0.000 0.000 0.000
12.9 5.61 0.055 0.010 0.045 0.000 0.000
36.1 5.61 0.329 0.086 0.244 0.000 0.000
59.3 5.62 0.133 0.102 0.031 0.000 0.000
85.4 5.62 0.154 0.154 0.000 0.000 0.000
122.2 5.62 0.186 0.186 0.000 0.000 0.000
163.9 5.63 0.035 0.035 0.000 0.000 0.000
12.9 5.80 0.048 0.009 0.039 0.000 0.000
https://geohazards.usgs.goy/deaggint/2008/out/Denison,White_M_2012.05.25_15.24.10.txt 5/25/2012
Page 12 of 14
36.9 5.80 0.327 O.074 0.253 0.000 0.000 0.000 0.000
59.6 5.81 0.178 0.098 0.080 0.000 0.000 0.000 0.000
85.6 5.81 0.248 0.245 0.003 0.000 0.000 0.000 0.000
122.8 5.81 0.332 0.332 0.000 0.000 0.000 0.000 0.000
166.6 5.82 0.087 O.087 0.000 0.000 0.000 0.000 0.000
13.6 6.01 0.040 0.007 0.033 0.000 0.000 0.000 0.000
37.3 6.01 0.226 0.046 0.181 0.000 0.000 0.000 0.000
59.4 6.01 0.195 0.072 0.123 0.000 0.000 0.000 0.000
85.7 6.01 0.261 0.196 0.065 0.000 0.000 0.000 0.000
123.3 6.01 0.415 0.406 0.009 0.000 0.000 0.000 0.000
168.5 6.02 0.131 0.131 0.000 0.000 0.000 0.000 0.000
213.5 6.02 0.016 0.016 0.000 0.000 0.000 0.000 0.000
16.6 6.19 0.061 O.all 0.050 0.000 0.000 0.000 0.000
38.4 6.22 0.199 O.038 0.161 0.000 0.000 0.000 0.000
60.0 6.21 0.232 0.066 0.166 0.000 0.000 0.000 0.000
85.7 6.22 0.362 0.173 0.190 0.000 0.000 0.000 0.000
123.8 6.22 0.642 0.478 0.164 0.000 0.000 0.000 0.000
169.4 6.22 0.252 0.252 0.000 0.000 0.000 0.000 0.000
216.8 6.23 0.045 0.045 0.000 0.000 0.000 0.000 0.000
14.0 6.42 O.029 0.005 0.023 0.000 0.000 0.000 0.000
37.7 6.42 0.146 0.027 0.119 0.000 0.000 0.000 0.000
60.5 6.42 0.170 0.040 0.131 0.000 0.000 0.000 0.000
85.6 6.42 0.319 0.106 0.213 0.000 0.000 0.000 0.000
124.4 6.42 0.629 0.308 0.321 0.000 0.000 0.000 0.000
170.2 6.43 0.304 0.292 0.013 0.000 0.000 0.000 0.000
217.8 6.43 0.073 0.073 0.000 0.000 0.000 0.000 0.000
264.5 6.44 0.008 0.008 0.000 0.000 0.000 0.000 0.000
13.0 6.59 0.016 0.003 O.013 0.000 0.000 0.000 0.000
38.1 6.59 0.091 0.017 0.074 0.000 0.000 0.000 0.000
62.7 6.60 0.126 0.027 0.099 0.000 0.000 0.000 0.000
87.4 6.59 0.208 0.056 0.152 0.000 0.000 0.000 0.000
125.3 6.59 0.471 0.170 0.301 0.000 0.000 0.000 0.000
171.a 6.59 0.272 0.222 0.050 0.000 0.000 0.000 0.000
218.6 6.59 0.076 0.076 0.000 0.000 0.000 0.000 0.000
266.7 6.59 0.012 0.012 0.000 0.000 0.000 0.000 0.000
13.5 6.78 0.021 0.004 0.017 0.000 0.000 0.000 0.000
38.2 6.77 0.101 0.018 0.082 0.000 0.000 0.000 0.000
60.8 6.78 0.138 0.027 0.111 0.000 0.000 0.000 0.000
85.9 6.78 0.288 0.065 0.223 0.000 0.000 0.000 0.000
125.6 6.78 0.674 0.189 0.485 0.000 0.000 0.000 0.000
172 .1 6.78 0.457 0.274 0.183 0.000 0.000 0.000 0.000
219.3 6.79 0.157 0.156 0.001 0.000 0.000 0.000 0.000
268.1 6.79 0.030 0.030 0.000 0.000 0.000 0.000 0.000
38.8 6.97 0.032 0.006 0.026 0.000 0.000 0.000 0.000
61.8 6.97 0.037 0.007 0.030 0.000 0.000 0.000 0.000
86.3 6.97 0.087 0.018 0.070 0.000 0.000 0.000 0.000
125.4 6.97 0.211 0.049 0.163 0.000 0.000 0.000 0.000
172.4 6.97 0.176 0.073 0.104 0.000 0.000 0.000 0.000
220.2 6.97 0.068 0.061 0.007 0.000 0.000 0.000 0.000
268.8 6.98 0.016 0.016 0.000 0.000 0.000 0.000 0.000
66.2 7.16 0.014 0.003 O.012 0.000 0.000 0.000 0.000
90.5 7.16 0.017 0.003 0.014 0.000 p.OOO 0.000 0.000
126.7 7.16 0.053 O.all 0.042 0.000 0.000 0.000 0.000
173.9 7.16 0.052 0.016 0.036 0.000 0.000 0.000 0.000
220.4 7.16 0.025 0.017 0.008 0.000 0.000 0.000 0.000
Summary statistics for above PSHA PGA deaggregation,R:::distance,e=epsilon:
Contribution from this GMPE(%):14.8
Mean sre-site R~89.4 km;M~5.99;epsO::::-0.06.Mean calculated for all sources.
Modal sre-site R=125.6 km;M=6.78;epsO:::-0.44 from peak (R.M)bin
MODE R*=125.6km;M*=6.78;EPS.INTERVAL:1 to 2 sigma %CONTRIB.=0.485
Principal sources (faults.subduction,random seismicity having >3%contribution)
Source Category:%contr.R(km)M epsilonO (mean values).
https://geohazards.usgs.gov/deaggintI2008/outIDenison_White_M_2012.05.25_15.24.10.txt 512512012
CEUS gridded
Individual fault
Fault ID
#*********End of
Page 13 of 14
14.85 89.4 5.99 -0.06
hazard details if its contribution to mean hazard>2%:
%contr.Rcd(km)M epsilonO Site-to-src azirnuth{d)
deaggregation corresponding to Tavakoli and Pezeshk 05 *********#
PSHA Deaggregation.%contributions.site:DenisOll_White_M long:109.500 W.,lat:37.500 N.
Vs30(m/s)=760.0 (some WUS atten.models use Site Class not Vs30).
NSHMP 2007-08 See USGS OFR 2008-1128.dM=0.2 below
Return period:2475 yrs.Exceedance PGA =0.07011 g.Weight *Computed_Rate_Ex O.176E-04
#Pr[at least one eq with median rnotion>=PGA in 50 yrs]=0',00241
#This deaggregation corresponds to Atkinson-Boore06,200 bar
DIST(KM)MAG(MW)ALL_EPS EPSILON>2
12.6 4.60 0.110 0.050
14.1 4.80 0.250 0.112
34.9 4.82 0.007 0.007
15.8 5.03 0.226 0.103
36.9 5.05 0.019 0.019
17.1 5.21 0.103 0.044
37.8 5.21 0.016 0.016
12.5 5.39 0.101 0.021
30.0 5.40 0.127 0.089
57.2 5.42 0.007 0.007
85.8 5.46 0.002 0.002
120.4 5.47 0.003 0.003
12.7 5.61 0.051 0.010
31.4 5.62 0.096 0.058
58.3 5.62 0.010 0.010
86.3 5.63 0.009 0.009
124.4 5.59 0.011 0.011
125.1 5.69 0.007 0.007
12.8 5.80 0.045 0.009
32.6 5.81 0.115 0.063
58.8 5.81 0.019 0.019
86.4 5.82 0.023 0.023
125.5 5.82 0.048 0.048
164.0 5.83 0.015 0.015
13.4 6.01 0.039 0.007
34.2 6.01 0.096 0.045
58.3 6.02 0.030 0.030
86.3 6.01 0.034 0.034
125.8 6.02 0.078 0.078
168.8 6.02 0.034 0.034
210.7 6.04 0.003 0.003
16.2 6.20 0.057 0.011
35.9 6.22 0.099 0.038
58.9 6.22 0.047 0.045
86.1 6.22 0.060 0.060
125.9 6.22 0.143 0.143
170.3 6.22 0.079 0.079
217.8 6.23 0.019 0.019
13.9 6.42 0.028 0.005
35.4 6.42 0.088 0.027
59.6 6.42 0.044 0.036
85.9 6.42 0.066 0.066'
126.0 6.43 0.162 0.162
171.2 6.43 0.104 0.104
219.5 6.43 0.036 0.036
267.6 6.44 0.007 0.007
12.9 6.59 0.016 0.003
36.1 6.59 0.061 0.017
61.6 6.60 0.038 0.027
87.6 6.59 0.051 0.051
126.5 6.59 0.135 0.135
172.0 6.59 0.097 0.097
1<EPS<2 O<EPS<l -l<EPS<O
0.060 0.000 0.000
0.138 0.000 0.000
0.000 0.000 0.000
0.124 0.000 0.000
0.000 0.000 0.000
0.059 0.000 0.000
0.000 0.000 0.000
0.079 0.000 0.000
0.038 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.041 0.000 0.000
0.037 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.036 0.000 0.000
0.052 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.031 0.000 0.000
0.051 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.046 0.000 0.000
0.061 0.000 0.000
0.002 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.023 0.000 0.000
0.061 0.000 0.000
0.008 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.013 0.000 0.000
0.044 0.000 0.000
0.012 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
-2<EPS<-1
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000,
EPS<-2
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
O.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
https://geohazards.usgs.gov/deaggint/2008/outlDenison_White_M_2012.05 .25_15.24.10.txt 512512012
220.4
269.5
318.0
13.5
36.6
59.8
86.0
126.3
172.7
221.1
270.6
331.8
13.9
37.7
61.a
86.2
125.8
172.8
221.7
271.4
342.4
19.4
41.a
65.0
90.5
126.7
173.8
221.7
271.9
353.2
6.59
6.59
6.60
6.78
6.77
6.78
6.78
6.78
6.78
6.79
6.79
6.80
6.97
6.97
6.97
6.97
6.97
6.97
6.97
6.98
6.96
7.16
7.16
7.16
7.16
7.16
7.16
7.16
7.16
7.16
0.039
0.011
0.002
0.021
0.074
0.054
0.086
0.218
0.168
0.078
0.026
0.011
0.007
0.025
0.017
0.031
0.078
0.067
0.032
0.013
0.007
0.003
0.005
0.007
0.007
0.022
0.020
0.011
0.005
0.004
0.039
0.011
0.002
0.004
0.018
0.027
0.065
0.187
0.168
0.078
O.026
0.011
0.001
0.006
0.007
0.018
0.049
0.062
0.032
0.013
0.007
0.001
0.001
0.003
0.003
0.011
0.016
0.011
0.005
0.004
0.000
0.000
0.000
0.017
0.056
0.027
0.021
0.031
0.000
0.000
0.000
0.000
0.005
0.019
0.010
0.014
0.029
0.005
0.000
0.000
0.000
0.002
0.004
0.005
0.004
0.011
0.005
0.000
0.000
0.000
0.000
O.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
O.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
Page 14 of 14
Summary statistics for above PSHA PGA deaggregation,R=distance,e=epsilon:
Contribution from this GMPE{%):4.3
Mean sre-site R=87.9 km;M=6.11;epsO=0.57.Mean calculated for all sources.
Modal sre-site R=14.1 km;M=4.80;epsO:-0.18 from peak (R,M)bin
MODE R*~126.3km;M*~6.77;EPS.INTERVAL:1 to 2 sigma %CONTRIB.~0.187
Principal sources
Source Category:
CEUS gridded
Individual fault
Fault ID
#*********End of
(faults,subduction,random seismicity having>3%contribution)
%contr.R{km) M epsilonO (mean values).
4.33 87.9 6.11 0.57
hazard details if its contribution to mean hazard>2%:
%contr.Rcd(km)M epsilonO Site~to-src azimuth (d)
deaggregation corresponding to Atkinson-Boore06,200 bar *********#
********************Intermountain Seismic Belt***********************************
https://geohazards.usgs.gov/deaggintI2008/outlDenison_White_M_2012.05.25_15.24.10.txt 512512012

ATTACHMENT 4.2

US GEOLOGICAL SURVEY DEAGGREGATION DATA

9,900 YEAR RETURN PERIOD

Page 1 of 11
EPS<-2
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.001
0.000
O.000
0.000
0.000
0.000
0.001
0.000
0.000
0.000
0.000
0.000
0.003
0.000
0.000
0.000
0.000
0.000
0.000
0.002
0.000
0.000
0.000
0.000
0.000
0.000
0.003
-2<EPS<-1
0.000
0.000
0.000
0.005
0.000
0.000
0.031
0.000
0.000
0.019
0.000
0.000
0.000
0.056
0.000
0.000
0.000
0.000
0.043
0.000
0.000
0.000
0.000
0.053
0.000
0.000
0.000
0.000
0.070
0.000
0.000
0.000
0.000
0.000
0.085
0.000
0.000
0.000
0.000
0.000
0.079
0.000
0.000
0.000
0.000
0.000
0.000
0.057
0.001
0.000
0.000
0.000
0.000
0.000
0.079
***Deaggregation of Seismic Hazard at One Period of Spectral Aceel.***
***Data from U.S.G.S.National Seismic Hazards Mapping Project,2008 version ***
PSHA Deaggregation.%contributions.site:Denison long:109.500 W.,lat:37.500 N.
Vs30(m!s)=760.0 (some WUS atten.models use Site Class not Vs30).
NSHMP 2007-08 See USGS OFR 2008-1128.dM=0.2 below
Return period:9900 yrs.Exceedance PGA =0.1511 g.Weight *Computed_Rate_Ex O.102E-03
#pr[at least one eq with median motion>=PGA in 50 yrsJ=O.00194
#This deaggregation corresponds to Mean Hazard w/all GMPEs
DIST(KM)MAG(MW)ALL_EPS EPSILON>2 1<EPS<2 O<EPS<l -l<EPS<O
15.5 4.60 4.032 0.469 1.782 1.495 0.285
38.2 4.61 0.503 0.449 0.054 0.000 0.000
56.3 4.62 0.051 0.051 0.000 0.000 0.000
13.4 4.79 6.327 0.429 2.129 3.079 0.686
30.6 4.82 3.489 1.410 1.948 0.131 0.000
58.5 4.82 0.245 0.245 0.000 0.000 0.000
12.0 5.03 4.314 0.164 0.981 2.302 0.836
30.6 5.03 4.752 1.314 2.781 0.657 0.000
61.0 5.04 0.543 0.543 0.000 0.000 0.000
12.2 5.21 1.739 0.059 0.351 0.870 0.440
31.4 5.21 2.483 0.500 1.409 0.574 0.000
62.0 5.21 0.409 0.405 0.004 0.000 0.000
88.1 5.21 0.060 0.060 0.000 0.000 0.000
12.4 5.39 2.758 0.085 0.509 1.278 0.831
32.2 5.40 5.009 0.725 2.729 1.555 0.000
62.7 5.40 1.127 0.994 0.133 0.000 0.000
89.1 5.41 0.261 0.261 0.000 0.000 0.000
113.4 5.42 0.104 0.104 0.000 0.000 0.000
12.5 5.61 1.422 0.040 0.240 0.602 0.497
33.1 5.62 3.397 0.341 1.690 1.333 0.033
63.5 5.62 1.088 0.726 0.361 0.000 0.000
89.6 5.62 0.353 0.353 0.000 0.000 0.000
116.8 5.63 0.239 0.239 0.000 0.000 0.000
12.6 5.80 1.287 0.035 0.207 0.519 0.474
33.8 5.81 3.657 0.294 1.667 1.571 0.124
63.8 5.81 1.408 0.718 0.691 0.000 0.000
89.9 5.81 0.540 0.537 0.002 0.000 0.000
118.5 5.82 0.484 0.484 0.000 0.000 0.000
13.3 6.01 1.127 0.029 0.174 0.437 0.416
35.0 6.01 2.997 0.182 1.086 1.555 0.174
60.4 6.01 1.442 0.351 1.064 0.027 0.000
85.1 6.02 1.003 0.690 0.313 0.000 0.000
119.8 6.02 0.814 0.810 0.004 0.000 0.000
166.2 6.02 0.128 0.128 0.000 0.000 0.000
16.06.201.6540.044 0.265 0.665 0.594
36.3 6.22 2.908 0.152 0.906 1.616 0.235
59.3 6.21 1.650 0.264 1.222 0.163 0.000
84.2 6.22 1.555 0.688 0.866 0.000 0.000
120.7 6.22 1.370 1.270 0.100 0.000 0.000
168.1 6.23 0.315 0.315 0.000 0.000 0.000
13.8 6.42 0,848 0.021 0.124 0.311 0.311
35.7 6.42 2.585 0.108 0.643 1.435 0.399
63.3 6.43 1.941 0.244 1.291 0.407 0.000
87.6 6.41 1.210 0.336 0.874 0.000 0.000
121.5 6.43 1.715 1.134 0.581 0.000 0.000
168.9 6.43 0.511 0.511 0.000 0.000 0.000
217.0 6.43 0.099 0.099 0.000 0.000 0.000
12.8 6.59 0.494 0.012 0.070 0.176 0.176
36.2 6.59 1.743 0.066 0.395 0.948 0.333
61.7 6.60 1.196 0.107 0.637 0.452 0.000
86.4 6.59 1.126 0.224 0.902 0.000 0.000
122.6 6.60 1.439 0.679 0.760 0.000 0.000
169.7 6.60 0.507 0.499 0.008 0.000 0.000
218.9 6.60 0.122 0.122 0.000 0.000 0.000
13.4 6.78 0.637 0.015 0.090 0.225 0.225
htlps:/Igeohazards.usgs.gov/deaggint/2008/outlDenison_2012.05.25_16.38.44.txt 5/2512012
Page 2 of 11
36.7 6.77 2.118 0.073 0.437 1.092 0.507 0.009 0.000
59.8 6.78 1.599 0.107 0.640 0.851 0.000 0.000 0.000
84.7 6.78 1.942 0.259 1.437 0.246 0.000 0.000 0.000
122.6 6.78 2.497 0.753 1.744 0.000 0.000 0.000 0.000
170.7 6.79 0.976 0.840 0.136 0.000 0.000 0.000 0.000
219.5 6.79 0.281 0.281 0.000 0.000 0.000 0.000 0.000
268.9 6.79 O. 063 0.063 0.000 0.000 0.000 0.000 0.000
13.9 6.97 0.204 0.005 0.028 0.072 0.072 0.027 0.001
37.7 6.97 0.735 0.023 0.138 0.346 0.220 0.008 0.000
61.1 6.97 0.526 0.028 0.166 0.323 0.009 0.000 0.000
85.2 6.97 0.774 0.070 0.419 0.285 0.000 0.000 0.000
122.5 6.97 1.074 0.194 0.839 0.041 0.000 0.000 0.000
170.6 6.97 0.482 0.283 0.199 0.000 0.000 0.000 0.000
220 .1 6.97 0.146 0.146 0.000 0.000 0.000 0.000 0.000
19.2 7.16 0.087 0.002 0.013 0.032 0.032 0.009 0.000
41.a 7.16 0.138 0.004 0.026 0.065 0.043 0.000 0.000
64.8 7.16 0.206 0.011 0.063 0.124 0.008 0.000 0.000
90.1 7.16 0.158 0.013 0.076 0.069 0.000 0.000 0.000
123.9 7.16 0.312 0.043 0.229 0.039 0.000 0.000 0.000
171.7 7.16 0.154 0.063 0.091 0.000 0.000 0.000 0.000
220.1 7.16 0.055 0.052 0.003 0.000 0.000 0.000 0.000
Summary statistics for above PSHA PGA deaqqr-eqat i.on,R=:distance,e:::epsilon:
Contribution from this GMPE(%):100.0
Mean sYe-site R=51.5 km:M=5.82;epsO=0.33.Mean calculated for all sources.
Modal sye-site R=13.4 km;M=4.79;epsO=-0.26 from peak (R,M)bin
MODE R*=12.2km;M*=4.80;EPS.INTERVAL:a to 1 sigma %CONTRIB.=3.079
Principal sources
Source Category:
CEUS gridded
Individual fault
Fault ID
#*********End of
(faults,subduction,random seismicity having>3%contribution)
%contr.R(km) M epsilonO (mean values).
100.00 51.5 5.82 0.33
hazard details if its contribution to mean hazard>2%:
%contr.Rcd(krn)M epsilonO Site-to-src azirnuth(d)
deaggregation corresponding to Mean Hazard w/all GMPEs *********#
EPS<-2
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
-2<EPS<-1
0.000
0.000
0.000
0.000
0.000
O.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
-l<EPS<O
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
PSHA Deaggregation.%contributions.site:Denison long:109.500 W./lat:37.500 N.
Vs30(m/s)=760.0 (some WUS atten.models use Site Class not Vs30).
NSHMP 2007-08 See USGS OFR 2008-1128.dM=0.2 below
Return period:9900 yrs.Exceedance PGA =0.1511 g.weight *Computed_Rate_Ex 0.281E-04
#Pr[at least one eq with median motion>=PGA in 50 yrs]=0.00212
#This deaggregation corresponds to Taro et al.1997
DIST(KM)MAG(MW)ALL_EPS EPSILON>2 1<EPS<2 O<EPS<l
11.7 4.60 0.756 0.155 0.577 0.024
30.1 4.61 0.584 0.504 0.080 0.000
56.9 4.62 0.034 0.034 0.000 0.000
11.8 4.80 1.361 0.254 1.045 0.061
30.6 4.81 1.260 0.986 0.274 0.000
59.4 4.82 0.124 0.124 0.000 0.000
12.1 5.03 1.068 0.164 0.824 0.080
31.6 5.03 1.404 0.910 0.494 0.000
61.5 5.04 0.252 0.252 0.000 0.000
86.1 5.06 0.017 0.017 0.000 0.000
12.3 5.21 0.433 0.059 0.327 0.047
32.4 5.21 0.728 0.406 0.322 0.000
62.5 5.21 0.181 0.181 0.000 0.000
87.6 5.21 0.025 0.025 0.000 0.000
12.4 5.39 0.689 0.085 0.495 0.108
33.1 5.40 1.448 0.672 0.776 0.000
63.1 5.40 0.476 0.476 0.001 0.000
88.7 5.40 0.104 0.104 0.000 0.000
108.7 5.41 0.021 0.021 0.000 0.000
12.6 5.61 0.360 0.040 0.239 0.081
34.1 5.62 1.014 0.341 0.671 0.002
63.9 5.62 0.471 0.440 0.031 0.000
https:llgeohazards.usgs.gov/deaggintI200S/outiDenison_2012.05.25_16.3S.44.txt 512512012
89.3
114.1
12.6
34.4
64.1
89.4
115.3
13 .3
35.5
61.2
84.8
118.2
161.9
16.0
36.5
62.8
86.8
118.6
164.2
13 .8
36.0
63.6
86.8
120.0
167.8
12.9
36.4
62.4
86.0
120.7
168.7
13.5
36.7
60.1
83.9
120.7
169.8
216.0
13 .9
37.9
61.3
84.7
121.2
170.3
218.9
19.3
41.a
64.7
89.7
121.8
170.7
5.63
5.64
5.80
5.81
5.81
5.81
5.82
6.01
6.01
6.01
6.02
6.02
6.03
6.20
6.22
6.22
6.21
6.22
6.22
6.42
6.42
6.43
6.41
6.42
6.43
6.59
6.59
6.60
6.59
6.61
6.61
6.7~
6.77
6.78
6.78
6.78
6.78
6.79
6.97
6.97
6.97
6.97
6.97
6.96
6.96
7.16
7.16
7.16
7.16
7.16
7.16
0.146
0.071
0.320
0.980
0.500
0.168
0.095
0.285
0.855
0.550
0.366
0.217
0.020
0.414
0.767
0.659
0.337
0.263
0.033
0.215
0.710
0.653
0.408
0.404
0.096
0.124
0.460
0.375
0.312
0.285
0.079
0.160
0.552
0.451
0.516
0.439
0.131
0.023
0.052
0.202
0.162
0.232
0.240
0.094
0.024
0.022
0.035
0.052
0.033
O.043.
0.015
0.146
0.071
0.035
0.294
0.448
0.168
0.095
0.029
0.182
0.337
0.350
0.217
0.020
0.044
0.152
0.367
0.328
0.263
0.033
0.021
0.108
0.244
0.296
0.402
0.096
0.012
0.066
0.107
0.208
0.272
0.079
0.015
0.073
0.107
0.258
0.404
0.131
0.023
0.005
0.023
0.028
0.070
0.171
0.094
0.024
0.002
0.004
O.all
0.013
0.036
0.015
0.000
0.000
0.207
0.680
0.052
0.000
0.000
0.174
0.654
0.214
0.016
0.000
0.000
0.264
0.588
0.292
0.009
0.000
0.000
0.124
0.544
0.410
0.112
0.002
0.000
0.070
0.348
0.268
0.104
0.013
0.000
0.090
0.410
0.344
0.258
0.034
0.000
0.000
0.028
0.137
0.133
0.162
0.068
0.000
0.000
0.013
0.026
0.041
0.020
0.007
0.000
0.000
0.000
0.078
0.006
0.000
0.000
0.000
0.082
0.019
0.000
0.000
0.000
0.000
0.105
0.027
0.000
0.000
0.000
0.000
0.070
0.058
0.000
0.000
0.000
0.000
0.042
0.047
0.000
0.000
0.000
0.000
0.055
0.069
0.000
0.000
0.000
0.000
0.000
0.018
0.042
0.001
0.000
0.000
0.000
0.000
0.007
0.005
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
O.000
0.000
O.000
o.000
o.000
O.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
Page 3 ofll
Summary statistics for above PSHA PGA deaggregation,R=distance,e=epsilon:
Contribution from this GMPE(%):27.5
Mean sre-site R=48.4 km;M=5.77;epsO=0.55.Mean calculated for all sources.
Modal src-site R=33.1 km;M=5.40;epsO=0.69 from peak (R,M)bin
MODE R*=11.9km;M*=4.80;EPS.INTERVAL:a to 1 sigma %CONTRIB.=1.045
principal sources
Source Category:
CEUS gridded
Individual fault
Fault ID
#*********End of
(faults,subduction,random seismicity having>3%contribution)
%contr.R{km) M epsilonO (mean values).
27.49 48.4 5.77 0.55
hazard details if its contribution to mean hazard>2%:
%contr.Rcd(km)M epsilonO Site-to-src azimuth(d)
deaggregation corresponding to Toro et al.1997 *********#
bttps://geohazards.usgs.gov/deaggintI2008/outlDenison_2012.05.25_16.38.44.txt 512512012
Page 4 of 11
PSHA Deaggregation.%contributions.site:Denison long:109.500 W./lat:37.500 N.
Vs30(m/s)=760.0 (some WUS atten.models use Site Class not Vs30).
NSHMP 2007-08 See USGS OFR 2008-1128.dM=0.2 below
Return period:9900 yrs.Exceedance PGA =0.1511 g.Weight *Computed_Rate_Ex O.258E-05
#Pr(at least one eq with median motion>=PGA in 50 yrs]=O,00059
#This deaggregation corresponds to
DIST(KM)
8.6
9.5
10.7
11.7
12.9
34.0
14.2
35.5
15.4
37.0
13.7
31.1
54.2
16.6
37.6
56.5
14.6
32.1
58.0
85.4
123.5
12.5
32.0
59.6
87.5
125.2
159.8
13 .2
33.0
58.3
85.8
125.3
167.0
16.2
36.4
59.9
86.0
124.8
125.3
168.9
213.0
18.5
39.4
63.0
90.4
125.9
170.9
MAG (MW)
4.61
4.80
5.03
5.21
5.40
5.42
5.62
5.63
5.80
5.82
6.01
6.03
6.03
6.21
6.22
6.23
6.41
6.44
6.43
6.44
6.44
6.59
6.59
6.60
6.59
6.59
6.60
6.78
6.78
6.79
6.79
6.79
6.80
6.96
6.98
6.98
6.98
6.96
7.01
6.98
7.00
7.16
7.16
7.16
7.16
7.16
7.16
ALL_EPS
0.101
0.250
0.251
0.123
0.237
0.003
0.152
0.006
0.166
0.013
0.122
0.047
0.002
0.187
0.039
0.006
0.104
0.077
0.009
0.006
0.011
0.057
0.072
0.011
0.008
0.018
0.003
0.074
0.102
0.022
0.020
0.045
0.016
0.031
0.032
0.009
0.011
0.016
0.007
0.011
0.001
0.009
0.007
0.004
0.003
0.009
0.005
EPSILON>2
0.063
0.146
0.144
0.063
0.114
0.003
0.071
0.006
0.079
0.013
0.039
0.043
0.002
0.066
0.039
0.006
0.027
0.057
0.009
0.006
0.011
0.012
0.047
0.011
0.008
0.018
0.003
0.015
0.061
O.022
0.020
0.045
0.016
0.007
0.020
0.009
O.all
0.016
0.007
O.all
0.001
0.002
0.004
0.004
0.003
0.009
0.005
Atkinson-Boore06,140 bar
1<EPS<2 O<EPS<l -l<EPS<O
0.038 0.000 0.000
0.105 0.000 0.000
0.107 0.000 0.000
0.060 0.000 0.000
0.123 0,000 0.000
0.000 0.000 0.000
0.080 0.000 0.000
0.000 0.000 0.000
0.087 0.000 0.000
0.000 0.000 0.000
0.083 0.000 0.000
0.004 0.000 0.000
0.000 0.000 0.000
0.121 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.076 0.000 0.000
0.020 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.045 0.000 0.000
0.025 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.059 0.000 0.000
0.041 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.024 0.000 0.000
0.012 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.007 0.000 0.000
0.003 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
-2<EPS<-1
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
EPS<-2
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
Summary statistics for above PSHA PGA deaggregation,R=distance,e=epsilon:
Contribution from this GMPE(%):2.5
Mean sye-site R=25.8 kmi M=5.84;epsO=0.23.Mean calculated for all sources.
Modal sre-site R=10.7 km;M=5.03;epsO=0.25 from peak (R.M)bin
MODE R*=11.0km;M*=4.80;EPS.INTERVAL:0 to 1 sigma %CONTRIB.=0.146
Principal sources
Source Category:
(faults,subduction,random seismicity having>3%contribution)
%contr.R(km)M epsilonO (mean values).
https://geohazards.usgs.gov/deaggillt/2008/out/Dellisoll_2012.05.25_16.38.44.txt 5/25/2012
Individual fault
Fault ID
#*********End of
Page 5 of 11
hazard details if its contribution to mean hazard>2%:
%contr.Rcd(km)M epsilonO Site-to-src azimuth (d)
deaggregation corresponding to Atkinson~Boore06/140bar *********#
PSHA Deaggregation.%contributions.site:Denison long:109.500 W./lat:37.500 N.
Vs30(m/s)=760.0 (some wus atten.models use Site Class not Vs30).
NSHMP 2007-08 See USGS OFR 2008-1128.dM=0.2 below
Return period:9900 yrs.Exceedance PGA =0.1511 g.Weight *Computed_Rate_Ex 0.229E-04
#Pr[at least one eq with median motion>=PGA in 50 yrsJ=0.00337
#This deaggregation corresponds to
DIST(KM)
14.7
31.a
12.2
30.1
57.6
12.4
31.3
61.1
87.4
12.6
32.2
62.4
89.3
12.7
33.1
63.2
89.9
115.4
12.7
34.1
64.0
90.1
119.5
12.8
34.9
64.5
90.3
120.9
162.5
13.5
35.7
60.7
85.8
121.6
167.8
16.3
37.0
59.7
85.0
122.4
169.6
214.9
13.9
36.3
64.1
88.3
123.1
170.4
218.2
12.9
36.8
62.1
86.8
MAG(MW)
4.59
4.64
4.80
4.80
4.82
5.03
5.03
5.04
5.08
5.21
5.21
5.21
5.21
5.39
5.40
5.41
5.41
5.42
5.61
5.62
5.62
5.62
5.62
5.80
5.80
5.81
5.81
5.81
5.83
6.01
6.01
6.01
6.02
6.01
6.02
6.20
6.22
6.21
6.22
6.22
6.22
6.24
6.42
6.42
6.43
6.41
6.42
6.43
6.43
6.59
6.59
6.60
6.59
ALL_EPS
0.582
0.224
0.901
0.939
0.052
0.674
1.014
0.134
0.012
0.263
0.516
0.105
0.024
0.404
1.014
0.292
0.099
0.075
0.201
0.641
0.266
0.119
0.136
0.178
0.688
0.375
0.198
0.270
0.046
0.153
0.522
0.329
0.304
0.365
0.096
0.229
0.499
0.375
0.469
0.599
0.218
0.036
0.112
0.411
0.410
0.319
0.624
0.277
0.073
0.064
0.272
0.236
0.293
EPSILON>2
0.271
0.215
0.254
0.826
0.052
0.164
0.771
0.134
0.012
0.059
0.348
0.105
0.024
0.085
0.615
0.292
0.099
0.075
0.040
0.335
0.266
0.119
0.136
0.035
0.294
0.370
0.198
0.270
0.046
0.029
0.182
0.286
0.304
0.365
0.096
0.044
0.152
0.262
0.468
0.599
0.218
0.036
0.021
0.108
0.244
0.308
0.624
0.277
0.073
0.012
0.066
0.107
0.224
Frankel et al.,1996
1<EPS<2 O<EPS<l ~l<EPS<O
0.310 0.000 0.000
0.008 0.000 0.000
0.646 0.000 0.000
0.113 0.000 0.000
0.000 0.000 0.000
0.510 0.000 0.000
0.243 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.204 0.000 0.000
0.167 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.319 0.000 0.000
0.399 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.161 0.000 0.000
0.306 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.144 0.000 0.000
0.393 0.000 0.000
0.005 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.124 0.000 0.000
0.340 0.000 0.000
0.043 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.185 0.000 0.000
0.347 0.000 0.000
0.112 0.000 0.000
0.002 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.091 0.000 0.000
0.303 0.000 0.000
0.166 0.000 0.000
0.011 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.000 0.000 0.000
0.052 0.000 0.000
0.206 0.000 0.000
0.129 0.000 0.000
0.069 0.000 0.000
-2<EPS<~1
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
EPS<-2
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
https:/Igeohazards.usgs.gov/deaggintI2008/out/Denison_2012.05.25_16.38.44.txt 512512012
Page 6 of 11
124.0
171.1
219.5
266.7
13.5
37.2
60.3
85.2
124.0
172 .0
220.2
269.1
13.9
38.0
61.4
85.6
123.8
172.a
220.9
270.2
19.4
41.2
65.4
90.3
125.1
173.2
220.9
6.59
6.59
6.59
6.60
6.78
6.77
6.78
6.78
6.78
6.78
6.79
6.79
6.97
6.97
6.97
6.97
6.97
6.97
6.97
6.98
7.16
7.16
7.16
7.16
7.16
7.16
7.16
0.493
0.257
0.082
0.016
0.082
0.323
0.299
0.459
0.774
0.445
0.171
0.043
0.026
0.107
0.089
0.158
0.276
0.179
0.072
0.022
0.011
0.021
0.036
0.033
0.079
0.058
0.027
0.489
0.257
0.082
0.016
0.015
0.073
0.107
0.259
0.681
0.445
0.171
0.043
0.005
0.023
0.028
O. 070
0.193
0.179
0.072
0.022
0.002
0.004
O.011
0.013
0.043
0.054
0.027
0.004
0.000
0.000
0.000
0.067
0.249
0.191
0.200
0.093
0.000
0.000
0.000
0.021
0.084
0.061
0.088
0.083
0.001
0.000
0.000
0.009
0.016
0.026
0.020
0.036
0.003
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
Summary statistics for above PSHA PGA deaggregation,R=distancet e=epsilon:
Contribution from this GMPE(%):22.4
Mean sre-site R=69.3 kID;M=5.91;epsO=0.55.Mean calculated for all sources.
Modal src-site R=33.1 km;M=5.40;epsO=0.42 from peak (R,M)bin
MODE R*=30.7km;M*=4.80;EPS.INTERVAL: 0 to 1 sigma %CONTRIB.=0.826
Principal sources
Source Category:
CEUS gridded
Individual fault
Fault ID
#*********End of
(faults,subduction,random seismicity having>3%contribution)
%contr.R{km) M epsilonO (mean values).
22.42 69.3 ·5.91 0.55
hazard details if its contribution to mean hazard>2%:
%contr.Rcd(km)M epsilonO Site-to-src azimuth(d)
deaggregation corresponding to Frankel et al.,1996 *********#
EPS<-2
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
-2<EPS<-1
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
PSHA Deaggregation.%contributions.site:Denison long:109.500 W.,lat:37.500 N.
Vs30(m/s)=760.0 (some WUS atten.models use Site Class not Vs30).
NSHMP 2007-08 See USGS OFR 2008-1128.dM=0.2 below
Return period:9900 yrs.Exceedance PGA =0.1511 g.Weight *Computed_Rate_Ex 0.148E-04
#Pr[at least one eq with median motion>=PGA in 50 yrs]=0.00388
#This deaggregation corresponds to Campbell CEUS Hybrid
DIST(KM)MAG(MW)ALL_EPS EPSILON>2 1<EPS<2 O<EPS<l -l<EPS<O
16.1 4.60 0.891 0.401 0.490 0.000 0.000
37.0 4.61 0.084 0.084 0.000 0.000 0.000
17.1 4.80 1.785 0.745 1.040 0.000 0.000
37.5 4.80 0.249 0.249 0.000 0.000 0.000
54.0 4.82 0.010 0.010 0.000 0.000 0.000
12.5 5.03 0.785 0.164 0.621 0.000 0.000
29.3 5.03 0.947 0.639 0.307 0.000 0.000
55.7 5.04 0.025 0.025 0.000 0.000 0.000
12.7 5.21 0.297 0.059 0.238 0.000 0.000
30.0 5.21 0.470 0.283 0.187 0.000 0.000
56.9 5.21 0.020 0.020 0.000 0.000 0.000
12.8 5.39 0.445 0.085 0.359 0.000 0.000
30.9 5.40 0.912 0.496 0.416 0.000 0.000
59.1 5.41 0.066 0.066 0.000 0.000 0.000
12.9 5.61 0.215 0.040 0.175 0.000 0.000
32.0 5.62 0.588 0.285 0.303 0.000 0.000
https://geohazards.usgs.gov/deaggillt/2008/out/Denison_2012.05.25_16.38.44.txt 5/25/2012
60.4
89.3
12 .9
33.0
61.2
89.9
113.7
13 .6
34.5
58.3
85.1
116.9
16.5
36.2
58.1
84.3
119.0
14.0
35.8
61.8
87.9
120.0
158.1
13.0
36.6
60.5
86.3
121.1
161.a
13.5
37.2
59.2
84.7
121.2
164.7
13 .9
38.2
60.6
85.2
121.4
165.4
19.4
41.3
64.3
90.1
122.9
167.5
5.62
5.63
5.80
5.80
5.81
5.82
5.83
6.01
6.01
6.01
6.02
6.02
6.19
6.22
6.22
6.22
6.22
6.42
6.42
6.43
6.42
6.43
6.44
6.59
6,59
6.60
6.59
6.59
6.60
6.78
6.77
6.78
6.78
6.79
6.79
6.97
6.97
6.97
6.98
6.98
6.98
7.16
7.16
7.16
7.16
7.16
7.16
0.070
0.012
0.188
0.644
0.111
0.028
0.019
0.159
0.510
0.134
0.059
0.043
0.240
0.501
0.189
0.117
0.098
0.114
0.430
0.217
0.099
0.134
0.009
0.065
0.290
0.154
0.113
0.132
0.015
0.083
0.348
0.234
0.225
0.269
0.041
0.026
0.116
0.077
0.095
0.124
0.025
0.012
0.023
0.033
0.024
0.044
0.011
0.070
0.012
0.035
0.280
0.111
0.028
0.019
0.029
0.182
0.134
0.059
0.043
0.044
0.152
0.171
0.117
0.098
0.021
0.108
0.175
0.099
0.134
0.009
0.012
0.066
0.101
0.113
0.132
0.015
0.015
0.073
0.107
0.215
0.269
0.041
0.005
0.023
0.028
0.070
0.122
0.025
0.002
0.004
0.011
0.013
0.037
0.011
0.000
0.000
0.153
0.364
0.000
0.000
0.000
0.130
0.328
0.000
0.000
0.000
0.196
0.349
0.017
0.000
0.000
0.093
0.322
0.042
0.000
0.000
0.000
0.053
0.224
0.053
0.000
0.000
0.000
0.068
0.275
0.127
0.009
0.000
0.000
0.021
0.093
0.049
0.025
0.002
0.000
0.009
0.018
0.022
0.011
0.007
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
Page 7 of 11
Summary statistics for above PSHA PGA deaggregatioll,R=distance,e=epsilon:
Contribution from this GMPE(%):14.5
Mean sre-site R=38.0 km;M=5.67;epsO=-0.23.Mean calculated for all sources.
Modal src-site R=17.1 km:M=4.80:epsO=-0.45 from peak (R,M)bin
MODE R*=14.5km:M*=4.80:EPS.INTERVAL:a to 1 sigma %CONTRIB.=1.040
Principal sources
Source Category:
CEUS gridded
Individual fault
Fault ID
#*********End of
(faults,subduction,random seismicity having>3%contribution)
%contr.R(km)M epsilonO (mean values).
14.50 38.0 5.67 -0.23
hazard details if its contribution to mean hazard>2%:
%contr.Rcd(km)M epsilonO Site-to-src azimuth(d)
deaggregation corresponding to Campbell CEUS Hybrid *********#
PSHA Deaggregation.%contributions.site:Denison long:109.500 W.,lat:37.500 N.
Vs30(m/s)=760.0 (some WUS atten.models use Site Class not Vs30).
NSHMP 2007-08 See USGS OFR 2008-1128.dM=0.2 below
https:llgeohazards.usgs.gov/deaggintI2008/outlDellison_2012.05.25_16.38.44.txt 512512012
Page 8 of 11
Return period:9900 yrs.Exceedance PGA =0.1511 g.Weight *Computed_Rate_Ex 0.155E-04
#Pr[at least one eq with median motion>=PGA in 50 yrs]=O.00190
#This deaggregation corresponds to Silva i-corner
DIST(KM)MAG(MW)ALL_EPS EPSILON>2
11.6 4.60 0.313 0.155
29.9 4.61 0.245 0.245
55.5 4.62 0.009 0.009
11.8 4.80 0.625 0.254
30.8 4.80 0.660 0.653
58.2 4.81 0.059 0.059
12.1 5.03 0.490 0.164
31.9 5.03 0.714 0.649
61.2 5.04 0.128 0.128
12.2 5.21 0.199 0.059
32.7 5.21 0.365 0.303
62.3 5.21 0.095 0.095
86.5 5.21 0.011 0.011
12.4 5.39 0.319 0.085
33.5 5.40 0.722 0.544
63.1 5.40 0.256 0.256
88.6 5.41 0.055 0.055
12.5 5.61 0.166 0.040
34.3 5.62 0.472 0.311
63.9 5.62 0.227 0.227
89.3 5.62 0.069 0.069
111.3 5.63 0.027 0.027
12.6 5.80 0.153 0.035
34.9 5.80 0.518 0.292
64.4 5.81 0.316 0.316
89.6 5.81 0.119 0.119
116.1 5.82 0.077 0.077
13.3 6.01 0.135 0.029
35.6 6.01 0.404 0.182
60.8 6.01 0.277 0.261
84.5 6.02 0.207 0.207
118.5 6.02 0.127 0.127
160.5 6.03 0.011 0.011
16.1 6.20 0.202 0.044
36.9 6.22 0.400 0.152
59.9 6.21 0.322 0.256
83.8 6.22 0.340 0.340
119.9 6.22 0.239 0.239
167.1 6.23 0.052 0.052
13.8 6.42 0.103 0.021
36.2 6.42 0.341 0.108
64.1 6.43 0.357 0.243
87.5 6.41 0.232 0.232
120.8 6.43 0.280 0.280
169.7 6.43 0.090 0.090
215.1 6.44 0.017 0.017
12.8 6.59 0.061 0.012
36.7 6.59 0.232 0.066
62.1 6.60 0.208 0.107
86.0 6.59 0.225 0.202
122.1 6.59 0.242 0.242
170.8 6.59 0.097 0.097
218.8 6.59 0.028 0.028
13.4 6.78 0.078 0.015
37.0 6.77 0.282 0.073
60.3 6.78 0.266 0.107
84.5 6.78 0.368 0.258
122.3 6.78 0.421 0.419
171.8 6.79 0.196 0.196
220.2 6.79 0.074 0.074
1<EPS<2 O<EPS<l
0.158 0.000
0.000 0.000
0.000 0.000
0.371 0.000
0.006 0.000
0.000 0.000
0.325 0.000
0.064 0.000
0.000 0.000
0.140 0.000
0.062 0.000
0.000 0.000
0.000 0.000
0.233 0.000
0.178 0.000
0.000 0.000
0.000 0.000
0.126 0.000
0.160 0.000
0.000 0.000
0.000 0.000
0.000 0.000
0.118 0.000
0.226 0.000
0.000 0.000
0.000 0.000
0.000 0.000
0.106 0.000
0.223 0.000
0.016 0.000
0.000 0.000
0.000 0.000
0.000 0.000
0.157 0.000
0.248 0.000
0.066 0.000
6.000 0.000
0.000 0.000
0.000 0.000
0.082 0.000
0.233 0.000
0.113 0.000
0.000 0.000
0.000 0.000
0.000 0.000
0.000 0.000
0.049 0.000
0.166 0.000
0.101 0.000
0.022 0.000
0.000 0.000
0.000 0.000
0.000 0.000
0.063 0.000
0.208 0.000
0.159 0.000
0.110 0.000
0.002 0.000
0.000 0.000
0.000 0.000
-l<EPS<O
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
-2<EPS<-1
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
EPS<-2
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
https://geohazards.usgs.gov/deaggintI2008/outlDenisOll_2012.05.25_16.38.44.txt 512512012
Page 9 of 11
269.1
13.9
37.9
61.4
85:0
122.4
171.9
221.1
270.8
19.2
41.2
65.3
90.0
123.9
173.1
221.3
6.80
6.97
6.97
6.97
6.97
6.97
6.97
6.98
6.98
7.16
7.16
7.16
7.16
7.16
7.16
7.16
0.019
0.025
0.096
0.081
0.129
0.164
0.091
0.037
0.013
0.011
0.019
0.033
0.027
0.050
0.032
0.016
0.019
0.005
0.023
0.028
0.070
0.153
O.091
0.037
0.013
0.002
0.004
0.011
0.013
0.041
0.032
0.016
0.000
0.020
0.073
0.053
0.059
0.011
0.000
0.000
0.000
0.009
0.014
0.023
0.014
0.009
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000O.ooq
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
Summary statistics for above PSHA PGA deaggregatioTI,R=distance,e=epsilon:
Contribution from this GMPE(%):15.2
Mean sre-site R=58.4 km;M=5.88;epsO=0.69.Mean calculated for all sources.
Modal sre-site R=33.5 km;M=5.40;epsO=0.74 from peak (R,M)bin
MODE R*=30.9km;M*=4.80;EPS.INTERVAL:a to 1 sigma %CONTRIB.=0.653
Principal sources
Source Category:
CEUS gridded
Individual fault
Fault ID
#*********End of
(faults,subduction,random seismicity having>3%contribution)
%contr.R(km) M epsilonO (mean values).
15.20 58.3 5.88 0.69
hazard details if its contribution to mean hazard>2%:
%contr.Rcd(km)M epsilonO Site-to-src azimuth (d)
deaggregation corresponding to Silva I-corner *********#
PSHA Deaggregation.%contributions.site:Denison long:109.500 W.,lat:37.500 N.
Vs30(m/s)=760.0 (some WUS atten.models use Site Class not Vs30).
NSHMP 2007-08 See USGS OFR 2008-1128.dM=0.2 below
Return period:9900 yrs.Exceedance PGA =0.1511 g.Weight *Computed~Rate_Ex O.144E-04
#pr[at least one eq with median motion>=PGA
#This deaggregation corresponds to
EPS<-2
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
-2<EPS<-1
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
in 50 yrs]=0.00378
and Pezeshk 05
O<EPS<l -l<EPS<O
Tavakoli
1<EPS<2
0.319
0.000
0.732
0.000
0.725
0.000
0.230
0.132
0.000
0.356
0.356
0.000
0.175
0.297
0.000
0.000
0.154
0.381
0.000
0.000
0.000
0.130
0.363
0.002
0.000
0.000
0.197
EPSILON>2
0.276
0.018
0.612
0.088
0.483
0.164
0.059
0.236
0.008
0.085
0.446
0.037
0.040
0.274
0.054
0.008
0.035
0.280
0.103
0.027
0.023
0.029
0.182
0.141
0.065
0.061
0.044
ALL_EPS
0.595
0.018
1.344
0.088
1.207
0.164
0.289
0.368
0.008
0.441
0.802
0.037
0.215
0.571
0.054
0.008
0.188
0.661
0.103
0.027
0.023
0.160
0.545
0.143
0.065
0.061
0.242
MAG(MW)
4.60
4.62
4.80
4.81
5.03
5.04
5.21
5.21
5.21
5.39
5.40
5.42
5.61
5.62
5.62
5.63
5.80
5.81
5.81
5.82
5.83
6.01
6.01
6.01
6.02
6.02
6.19
DIST(KM)
14.2
34.9
15.6
36.2
17.3
37.3
12.6
29.1
55.3
12.7
30.3
57.5
12.9
31.7
59.7
89.2
12.9
33.0
60.8
90.1
115.3
13.6
34.7
58.2
85.5
118.7
16.5
https://geohazal'ds.usgs.gov/deaggint/2008/out/Denison_2012.05.25_16.38,44.txt 5/25/2012
Page 10of 11
36.6
58.1
84.7
120.3
157.5
14.0
36.2
62.0
88.2
121.1
161.4
13.0
37.0
60.7
86.7
122.1
164.3
13 .5
37.5
59.3
85.1
122.2
166.6
13.9
38.5
60.8
85.5
122.3
166.7
19.4
41.5
64.6
90.2
123.7
168.5
6.22
6.22
6.22
6.23
6.25
6.42
6.42
6.43
6.42
6.43
6.43
6.59
6.59
6.60
6.59
6.59
6.59
6.78
6.77
6.78
6.78
6.78
6.79
6.97
6.97
6.97
6.98
6.98
6.98
7.16
7.16
7.16
7.16
7.16
7.16
0.546
0.218
0.144
0.150
0.009
0.114
0.466
0.264
0.132
0.216
0.026
0.065
0.311
0.189
0.154
0.217
0.036
0.083
0.368
0.283
0.305
0.439
0.092
0.026
0.121
O.092
0.127
0.197
0.052
0.012
0.023
0.039
0.032
0.068
0.022
0.152
0.185
0.144
0.150
0.009
0.021
0.108
0.194
0.132
0.216
0.026
0.012
0.066
0.106
0.154
0.217
0.036
0.015
0.073
0.107
0.253
0.435
O.092
0.005
0.023
0.028
0.070
0.168
0.052
0.002
0.004
0.011
0.013
0.043
0.022
0.394
0.033
0.000
0.000
0.000
0.093
0.358
0.070
0.000
0.000
0.000
0.053
0.245
0.082
0.000
0.000
0.000
0.068
0.295
0.176
0.053
0.003
0.000
0.021
0.098
0.064
0.057
0.029
0.000
0.009
0.019
0.028
0.019
0.026
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
.O.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
Summary statistics for above PSHA PGA deaggregatioll,R=distance,e=epsilon:
Contribution from this GMPE(%):14.1
Mean sre-site R=44.5 km;M=5.84;epsO=-0.22.Mean calculated for all sources.
Modal src-site R=15.6 km;M=4.80;epsO=-0.27 from peak (R,M)bin
MODE R*=12.3km;M*=4.80;EPS.INTERVAL:a to 1 sigma % CONTRIB.=0.732
Principal sources
Source Category:
CEUS gridded
Individual fault
Fault ID
#*********End of
(faults,subduction,random seismicity having>3%contribution)
%contr.R{km) M epsilonO (mean values).
14.08 44.5 5.84 -0.22
hazard details if its contribution to mean hazard>2%:
%contr.Rcd{km)M epsilonO Site-to-src azimuth (d)
deaggregation corresponding to Tavakoli and Pezeshk 05 *********#
EPS<-2
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
-2<EPS<-1
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
PSHA Deaggregation.%contributions.site:Denison long:109.500 W.,lat:37.500 N.
Vs30(m/s)=760.0 (some WUS atten.models use Site Class not Vs30).
NSHMP 2007-08 See USGS OFR 2008-1128.dM=0.2 below
Return period:9900 yrs.Exceedance PGA =0.1511 g.Weight *Computed_Rate_Ex O.388E-05
#Pr[at least one eq with median motion>=PGA in 50 yrs]=0.00086
#This deaggregation corresponds to Atkinson-Boore06,200 bar
DIST(KM)MAG(MW)ALL_EPS EPSILON>2 1<EPS<2 O<EPS<l -l<EPS<O
9.3 4.61 0.144 0.083 0.061 0.000 0.000
10.3 4.80 0.352 0.204 0.148 0.000 0.000
11.7 5.03 0.348 0.176 0.173 0.000 0.000
12.9 5.21 0.169 0.080 0.089 0.000 0.000
33.9 5.21 0.002 0.002 0.000 0.000 0.000
14.1 5.40 0.321 0.149 0.171 0.000 0.000
35.4 5.42 0.011 0.011 0.000 0.000 0.000
15.5 5.61 0.202 0.096 0.106 0.000 0.000
https:llgeohazards.usgs.gov/deaggintl2008/outlDenison_2012.05.25_16.38,44.txt 512512012
37.0
15.3
31.6
55.1
12.9
31.a
56.1
17.3
38.0
57.5
85.8
123.8
15.2
33.3
58.5
85.6
124.9
125.2
162.4
12.7
33.1
60.2
87.6
125.7
167.5
13.3
34.0
58.7
85.8
125.7
170.0
214.6
16.6
37.2
60.2
86.1
125.2
170.3
218.7
18.9
39.9
63.5
90.4
126.1
171.8
219.6
5.62
5.79
5.84
5.83
6.01
6.01
6.02
6.21
6.21
6.22
6.23
6.24
6.41
6.43
6.43
6.43
6.40
6.49
6.44
6.59
6.59
6.60
6.59
6.59
6.60
6.78
6.77
6.79
6.79
6.79
6.79
6.81
6.96
6.98
6.98
6.98
6.98
6.98
6.98
7.16
7.16
7.16
7.16
7.16
7.16
7.16
0.017
0.186
0.061
0.002
0.126
0.103
0.008
0.226
0.072
0.018
o.all
0.021
0.117
0.120
0.023
0.021
0.031
0.015
O.all
0.060
0.106
0.024
0.022
0.052
0.021
0.078
0.144
0.044
0.048
0.111
0.055
0.009
0.033
0.045
0.017
0.022
0.051
0.029
0.008
0.010
0.010
0.008
0.006
0.018
0.011
0.004
0.017
0.073
0.054
0.002
0.029
0.084
0.008
0.066
0.070
0.018
0.011
0.021
0.027
0.079
0.023
0.021
0.031
0.015
o.all
0.012
0.059
0.024
O.022
0.052
O.021
0.015
0.071
0.044
0.048
0.111
0.055
0.009
0.007
0.021
0.017
0.022
0.051
0.029
0.008
0.002
0.004
0.008
0.006
0.018
0.011
0.004
0.000
0.113
0.007
0.000
0.096
0.018
0.000
0.160
0.002
0.000
0.000
0.000
0.089
0.041
0.000
0.000
0.000
0.000
0.000
0.048
0.046
0.000
0.000
0.000
0.000
0.063
0.073
0.000
0.000
0.000
0.000
0.000
0.027
0.024
0.000
0.000
0.000
0.000
0.000
0.008
0.006
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
o.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0:000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
Page 11 of 11
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
0.000
Summary statistics for above PSHA PGA deaggregation,R=distance,e=epsilon:
Contribution from this GMPE(%):3.8
Mean sre-site R=36.8 km;M=5.90;epsO=0.30.Mean calculated for all sources.
Modal src-site R=10.3 km;M=4.80;epsO=0.25 from peak (R,M)bin
MODE R*=12.3km;M*=4.80;EPS.INTERVAL:a to 1 sigma %CONTRIB.=0.204
principal sources
Source Category:
CEUS gridded
Individual fault
Fault ID
#*********End of
(faults,subduction,random seismicity having>3%contribution)
%contr.R(krn)M epsilonO (mean values).
3.79 36.8 5.90 0.30
hazard details if its contribution to mean hazard>2%:
%contr.Rcd(krn)M epsilonO Site-to-src azirnuth(d)
deaggregation corresponding to Atkinson-Boore06,200 bar *********#
********************Intermountain Seismic Belt***********************************
https://geohazards.usgs.gov/deaggillt/2008/out/Denison_2012.05.25_16.38.44.txt 512512012

ATTACHMENT E

SUPPORTING DOCUMENTATION FOR INTERROGATORY 07/1:

UPDATED SETTLEMENT ANALYSES

1009740 SEll.MON
G MWH
FIGURE 1.1
----~2~O FEET200CONTOURINTERVAL
SETTL
CLAMATIONPROJECTMILLTAILINGSREWHITE MESAOENISOE{)~ ~
MIN C rp.Mines(USA)0Denison
PHASE 1 CONSOLIDATION: AFTER INTERIM COVER PLACEMENT, PRIOR TO DE-WATERING
Notes
t1 occurs at the beginning of tailings dewatering (1/1/2009)
t2 occurs at midpoint of final cover placement over a given location
t3 occurs at 99% of consolidation due to final cover
It is assumed that there is an additional 3 feet of perched zones of saturation above the capillary fringe.
SOIL PROPERTIES
Tailings
2.75 Specific gravity of tailings, Gs-tailing Average calculated from laboratory tests (Chen and Associates, 1987 and Western Colorado Testing, 1999)
86.31 Dry unit weight of tailings prior to t0, γd0-tailing (pcf)Calculated from a mass tonnage and tailings cell storage volume. (MWH, 2011)
16.2% Long-term moisture content of tailings above the capillary fringe, w Chen and Associates, 1987. This assumption is more conservative for settlement analysis than the value used in radon modeling (results in higher vertical stress).
100.29 Moist unit weight of tailings (above capillary fringe) prior to t0, γm0-tailing (pcf)Calculated
0.99 Void ratio of tailings prior to t0, e0-tailing Calculated
117.3 Saturated unit weight of tailings prior to t0, γsat0-tailing (pcf)Calculated
2.00 SPT blow count for tailings prior to t0, Nm (blows/foot)(uncorrected)Conservatively assumed a blow count of 2 which is representative of very loose granular soils. Range of uncorrected (SPT) blow counts for medium dense fine granular soils with wet unit weights of 110 to 130 pcf is 7 to 15 (Bowles, 1988).
45.1%Percent saturation of unsaturated tailings prior to t0, S0 (%)Calculated
30%Fines content of tailings, FCtailing (%)Average calculated from entirety of laboratory testing results (Western Colorado Testing, 1999. Chen and Associates, 1987. CSM, 1978. Denison, 2009.)
Cover Soil
118.0 Maximum dry unit weight of cover soil γcover-max (pcf)Average calculated from laboratory testing results (UWM, 2012)
100.7 Moist unit weight of cover soil at 80% relative compaction, γcover95 (pcf)Calculated
107.0 Moist unit weight of cover soil at 85% relative compaction, γcover95 (pcf)Calculated
119.6 Moist unit weight of cover soil at 95% relative compaction, γcover95 (pcf)Calculated
6.7% Long-term moisture content of cover soil, w (%) Estimated based on measured 15bar water content. (UWM, 2012)
Saturated Zone
5,601.95 Elevation of Phreatic Surface at t0 (ft amsl)Average of water level measurements taken in first quarter 2009
8.00 Height of Capillary Fringe (ft)Estimated zone with 90%+ saturation: based on % fines and PI. (Fredlund, Fredlund, and Houston, 2003)
3.00 Combined Thickness of Perched Zones (ft)Assumed
Cell 2W1 Cell 2W2 Cell 2W3 Cell 2W4 2W5-C 2W4-N 2W4-S 2W3-S Cell 2 East 2E1-N 2E1-1S 2E1-2S 2W7-C 2W7-N 2W7-S 2W6-N 2W6-C 2W6-S
Elevation of Native Ground (ft)5598.50 5596.00 5594.50 5590.00 5585.50 5592.50 5587.00 5591.50 5591.50 5599.00 5591.00 5589.00 5591.50 5593.00 5588.50 5591.00 5586.00 5585.00 From subgrade topographic drawing
Elevation of Top of Tailings Prior to t0 (ft)5613.50 5613.50 5613.50 5613.50 5613.50 5613.50 5613.50 5613.50 5617.00 5621.40 5614.50 5613.50 5613.50 5613.50 5613.50 5613.50 5613.50 5613.50 Assumed a flat tailings surface at t0 with elevation of 5613.5'
Elevation of Top of Interim Cover Prior to Consolidation (ft) 5618.00 5618.00 5617.30 5617.40 5617.10 5616.50 5616.50 5617.40 5622.00 5626.00 5622.00 5620.00 5621.50 5621.70 5619.20 5616.90 5616.50 5616.50 From CAD Drawing: 1009740X001.dwg (LiDAR). Some values adjusted to maintain a min. of 3ft of int. cover.
Thickness of Tailings Prior to t0 (ft)15.00 17.50 19.00 23.50 28.00 21.00 26.50 22.00 25.50 22.40 23.50 24.50 22.00 20.50 25.00 22.50 27.50 28.50 Calculated
Thickness of Interim Cover (ft)4.50 4.50 3.80 3.90 3.60 3.00 3.00 3.90 5.00 4.60 7.50 6.50 8.00 8.20 5.70 3.40 3.00 3.00 Calculated
Elevation of Top of Capillary Fringe Prior to t1 (ft amsl)5609.95 5609.95 5609.95 5609.95 5609.95 5609.95 5609.95 5609.95 5609.95 5609.95 5609.95 5609.95 5609.95 5609.95 5609.95 5609.95 5609.95 5609.95 Calculated from phreatic surface and capillary fringe.
Load Induced by Interim Cover, Δpint (psf)453.26 453.26 382.75 392.83 362.61 302.17 302.17 392.83 503.62 463.33 755.44 654.71 805.80 825.94 574.13 342.46 302.17 302.17 Calculated
Observed Settlement Prior to t1 (ft)0.51 1.05 0.55 1.02 0.02 0.01 0.05 0.71 0.24 0.19 0.15 0.14 0.17 0.03 0.02 0.04 0.06 0.12 From monitoring point data
Total Settlement Estimated by Model from t0 to t1 (ft)0.48 0.90 0.52 0.80 - - - 0.59 - - - - - - - - - - Calculated
Zone of Saturated Tailings
Thickness of Saturated Tailings from t0 to t1 (ft)14.45 16.95 18.45 22.95 27.45 20.45 25.95 21.45 21.45 13.95 21.95 23.95 21.45 19.95 24.45 21.95 26.95 27.95 Calculated
Volume of Solids in Saturated Tailings at t0, Vs0, (ft3/ft2)7.27 8.52 9.28 11.54 13.80 10.28 13.05 10.79 10.79 7.01 11.04 12.04 10.79 10.03 12.30 11.04 13.55 14.06 Calculated
Volume of Voids in Saturated Tailings at t0, Vv0, (ft3/ft2)7.18 8.42 9.17 11.41 13.64 10.16 12.90 10.66 10.66 6.93 10.91 11.90 10.66 9.91 12.15 10.91 13.39 13.89 Calculated
Volume of Voids in Saturated Tailings at t1, Vv1, (ft3/ft2)6.70 7.52 8.65 10.61 13.62 10.15 12.85 10.07 10.42 6.74 10.76 11.76 10.49 9.88 12.13 10.87 13.33 13.77 Calculated using settlement model (using observed settlement where model is not available).
Void Ratio of Saturated Tailings at t1, e1-tailing 0.86 0.80 0.88 0.86 0.99 0.99 0.98 0.89 0.94 0.94 0.96 0.97 0.96 0.98 0.98 0.98 0.98 0.97 Calculated
Saturated unit weight of tailings at t1, γsat1-tailing (pcf)120.95 123.12 120.40 121.13 117.40 117.38 117.53 120.33 118.55 118.81 118.07 117.96 118.19 117.49 117.41 117.52 117.57 117.79 Calculated
Elevation of Midpoint of Saturated Layer prior to t1 (ft AMSL)5604.22 5602.97 5602.22 5599.97 5597.72 5601.22 5598.47 5600.72 5600.72 5604.47 5600.47 5599.47 5600.72 5601.47 5599.22 5600.47 5597.97 5597.47 Calculated
Effective Stress at Midpoint of Saturated Layer at t0, σ0'1169.92 1238.58 1279.77 1403.35 1526.93 1334.70 1485.74 1362.16 1713.18 1948.50 1476.18 1430.81 1362.16 1320.97 1444.55 1375.89 1513.20 1540.66 Calculated
Effective Stress at Midpoint of Saturated Layer at t1, σ1'1643.95 1732.28 1686.30 1834.15 1890.51 1637.34 1790.33 1782.69 2228.08 2419.98 2238.69 2092.21 2175.94 2148.30 2019.64 1720.24 1818.29 1848.69 Calculated
Observed Compression Index of Tailings, Cc-tails 0.83 1.30 0.88 1.11 0.03 0.02 0.09 0.88 0.38 0.56 0.15 0.14 0.15 0.03 0.02 0.07 0.11 0.21 Calculated based on observed settlement
Settlement Model
Start Date of Primary Consolidation, t0 5/17/1989 7/23/1991 7/23/1991 7/23/1991 7/27/2005 7/27/2005 7/27/2005 4/4/1999 5/17/1989 8/4/1998 8/4/1998 8/4/1998 4/4/1999 7/27/2005 7/27/2005 7/27/2005 7/27/2005 7/27/2005 Calculated as 30 days before first survey of monitoring point.
Date on Which 90% of Settlement had Occurred 1/1/1999 10/13/1996 11/3/1999 8/15/1998 N/A N/A N/A 10/31/2000 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A Calculated from t0 and elapsed time to t90.
Time Elapsed for 90% of Consolidation to Occur, t90, (days)3,516 1,910 3,025 2,581 N/A N/A N/A 576 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A Calculated using the sqare root of time method (Bowles, 1992)
Coefficient of Consolidation of Tailings Cv-tails (ft2/d)0.032 0.086 0.067 0.131 N/A N/A N/A 0.501 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A Calculated (Wray, 1996. Equation 9-6, page 109)
Coefficient of Consolidation of Tailings Cv-tails (cm2/sec)0.00034 0.00093 0.00072 0.00141 0.00539 Calculated
Dry Unit Weight of Tailings (in saturated zone) at t1, γdry-1 (pcf)92.01 95.42 91.15 92.29 86.44 86.39 86.64 91.03 88.23 88.65 87.48 87.31 87.67 86.57 86.45 86.62 86.69 87.05 Calculated
Saturated Unit Weight of Tailings at t1, γmoist-1 (pcf)120.95 123.12 120.40 121.13 117.40 117.38 117.53 120.33 118.55 118.81 118.07 117.96 118.19 117.49 117.41 117.52 117.57 117.79 Calculated
t0 occurs at midpoint of interim cover placement over a given location Was originally assumed to be 120 days before first monitoring event. This was determined to be unreasonable due to excessively high Cc values and impossibly low (even negative) void ratios. Has been revised to 30
days before first monitoring event, except for Cell 2W2, for which t0 coincides with the first monitoring event.
PHASE 2 CONSOLIDATION: AFTER DE-WATERING BEGINS, PRIOR TO PLACEMENT OF FINAL COVER
Notes
t0 occurs at midpoint of interim cover placement over a given location
t1 occurs at the beginning of tailings dewatering (1/1/2009)
t2 occurs at midpoint of final cover placement over a given location
t3 occurs at 99% of consolidation due to final cover
SOIL PROPERTIES
Tailings
2.75 Specific gravity of tailings, Gs-tailing Average calculated from laboratory tests (Chen and Associates, 1987 and Western Colorado Testing, 1999)
16.2% Long-term moisture content of unsaturated tailings, w Chen and Associates, 1987. This assumption is more conservative for settlement analysis than the value used in radon modeling (results in higher vertical stress).
30%Fines content of tailings, FCtailing (%)Average calculated from entirety of laboratory testing results (Western Colorado Testing, 1999. Chen and Associates, 1987. CSM, 1978. Denison, 2009.)
0.032 Coefficient of Consolidation of Tailings (lower bound), Cv-min (ft2/day)Calculated from phase 1 model
100.29 Moist unit weight of tailings (above capillary fringe) prior to t0, γm0-tailing (pcf)Calculated
Cover Soil
118.0 Maximum dry unit weight of cover soil γcover-max (pcf)Average calculated from laboratory testing results (UWM, 2012)
100.7 Moist unit weight of cover soil at 80% relative compaction, γcover95 (pcf)Calculated
107.0 Moist unit weight of cover soil at 85% relative compaction, γcover95 (pcf)Calculated
119.6 Moist unit weight of cover soil at 95% relative compaction, γcover95 (pcf)Calculated
6.7% Long-term moisture content of cover soil, w (%)Estimated based on measured 15bar water content. (UWM, 2012)
Saturated Zone
5601.95 Phreatic Surface Elevation at t1 (ft AMSL)Calculated average of 2009 first-quarter water levels
8.00 Height of Capillary Fringe (ft)Estimated zone with 90%+ saturation: based on % fines and PI. (Fredlund, Fredlund, and Houston, 2003)
5,609.95 Elevation of Top of Capillary Fringe at t1 (ft amsl)Calculated from phreatic surface and capillary fringe.
7,590,661 Total Volume of Saturated Tailings at t2 (cf)Calculated assuming and average saturated thickness of 1.05 meters over the entire footprint of the bottom of the cell
5,593.03 Phreatic Surface Elevation at t2 (ft AMSL)Calculated from total volume of saturated tailings and stage-storage curve for Cell 2
3.00 Combined Thickness of Perched Zones (ft)Assumed
Cell 2W1 Cell 2W2 Cell 2W3 Cell 2W4 2W5-C 2W4-N 2W4-S 2W3-S Cell 2 East 2E1-N 2E1-1S 2E1-2S 2W7-C 2W7-N 2W7-S 2W6-N 2W6-C 2W6-S
Elevation of Native Ground (ft)5598.50 5596.00 5594.50 5590.00 5585.50 5592.50 5587.00 5591.50 5591.50 5599.00 5591.00 5589.00 5591.50 5593.00 5588.50 5591.00 5586.00 5585.00 From subgrade topographic drawing
Elevation of Top of Tailings at t1 (ft)5613.02 5612.60 5612.98 5612.70 5613.48 5613.49 5613.45 5612.91 5616.76 5621.21 5614.35 5613.36 5613.33 5613.47 5613.48 5613.46 5613.44 5613.38 Calculated from intial tailings surface and Phase 1 settlement
Elevation of Top of Interim Cover at t1 (ft)5617.52 5617.10 5616.78 5616.60 5617.08 5616.49 5616.45 5616.81 5621.76 5625.81 5621.85 5619.86 5621.33 5621.67 5619.18 5616.86 5616.44 5616.38 Calculated
Thickness of Tailings at t1 (ft)14.52 16.60 18.48 22.70 27.98 20.99 26.45 21.41 25.26 22.21 23.35 24.36 21.83 20.47 24.98 22.46 27.44 28.38 Calculated
Thickness of Interim Cover (ft)4.50 4.50 3.80 3.90 3.60 3.00 3.00 3.90 5.00 4.60 7.50 6.50 8.00 8.20 5.70 3.40 3.00 3.00 Calculated
Load Induced by Interim Cover, Δpint (psf)453.26 453.26 382.75 392.83 362.61 302.17 302.17 392.83 503.62 463.33 755.44 654.71 805.80 825.94 574.13 342.46 302.17 302.17 Calculated
Void Ratio of Saturated Tailings at t1, e1-tailing 0.86 0.80 0.88 0.86 0.99 0.99 0.98 0.89 0.94 0.94 0.96 0.97 0.96 0.98 0.98 0.98 0.98 0.97 Calculated based on initial void ratio and Phase 1 consolidation
Dry Unit Weight of Saturated Tailings at t1, γdry-1 (pcf)92.01 95.42 91.15 92.29 86.44 86.39 86.64 91.03 88.23 88.65 87.48 87.31 87.67 86.57 86.45 86.62 86.69 87.05 Calculated
Saturated Unit Weight of Tailings at t1, γsat-1 (pcf)120.95 123.12 120.40 121.13 117.40 117.38 117.53 120.33 118.55 118.81 118.07 117.96 118.19 117.49 117.41 117.52 117.57 117.79 Calculated
Compression Index of Tailings, Cc-tails 0.83 1.30 0.88 1.11 0.03 0.02 0.09 0.88 0.38 0.56 0.15 0.14 0.15 0.03 0.02 0.07 0.11 0.21 Calculated using Phase 1 settle model (or observed settlement where model is unavailable).
Coefficient of Consolidation of Tailings Cv-tails (ft2/d)0.032 0.086 0.067 0.131 N/A N/A N/A 0.501 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A Calculated (Wray, 1996. Equation 9-6, page 109)
Settlement
Phase 2 Upper Zone
Elevation of Top of Upper Zone at t1 (ft)5604.95 5604.95 5604.95 5604.95 5604.95 5604.95 5604.95 5604.95 5604.95 5604.95 5604.95 5604.95 5604.95 5604.95 5604.95 5604.95 5604.95 5604.95
Elevation of Bottom of Upper Zone at t1 (ft)5598.50 5596.00 5594.50 5593.03 5593.03 5593.03 5593.03 5593.03 5593.03 5599.00 5593.03 5593.03 5593.03 5593.03 5593.03 5593.03 5593.03 5593.03
Elevation of Midpoint of Upper Zone at t1 (ft)5601.72 5600.47 5599.72 5598.99 5598.99 5598.99 5598.99 5598.99 5598.99 5601.97 5598.99 5598.99 5598.99 5598.99 5598.99 5598.99 5598.99 5598.99
Effective Stress at Midpoint of Upper Zone at t1, σ1-top' (psf)1742.19 1793.83 1779.16 1811.87 1819.03 1759.31 1757.02 1824.13 2301.52 2540.29 2306.42 2105.22 2255.79 2282.29 2030.66 1798.19 1756.38 1752.83 Calculated
Effective Stress at Midpoint of Upper Zone at t2, σ2-top' (psf)1756.13 1885.76 1917.89 1996.59 2003.74 1944.03 1941.73 2008.85 2486.24 2540.29 2491.13 2289.94 2440.50 2467.00 2215.37 1982.90 1941.09 1937.55 Calculated
Anticipated Consolidation of Upper Zone from t1 to t2, Stop (ft)0.01 0.14 0.16 0.30 0.01 0.01 0.02 0.23 0.08 0.00 0.03 0.03 0.03 0.01 0.01 0.02 0.03 0.06 Calculated using consolidation theory (Coduto, 1999. Equation 12.20, Page 436)
Phase 2 Lower Zone
Elevation of Top of Lower Zone at t1 (ft)5598.50 5596.00 5594.50 5593.03 5593.03 5593.03 5593.03 5593.03 5593.03 5599.00 5593.03 5593.03 5593.03 5593.03 5593.03 5593.03 5593.03 5593.03
Elevation of Bottom of Lower Zone (ft)5598.50 5596.00 5594.50 5590.00 5585.50 5592.50 5587.00 5591.50 5591.50 5599.00 5591.00 5589.00 5591.50 5593.00 5588.50 5591.00 5586.00 5585.00
Elevation of Midpoint of Lower Zone (ft)5598.50 5596.00 5594.50 5591.51 5589.26 5592.76 5590.01 5592.26 5592.26 5599.00 5592.01 5591.01 5592.26 5593.01 5590.76 5592.01 5589.51 5589.01
Effective Stress at Midpoint of Lower Zone at t1, σ1-bott' (psf)N/A N/A N/A 2250.79 2353.85 2101.46 2251.76 2213.61 2679.02 N/A 2694.63 2548.24 2630.89 2611.35 2483.06 2182.58 2279.00 2305.29 Calculated
Effective Stress at Midpoint of Lower Zone at t2, σ2-bott' (psf)N/A N/A N/A 2807.42 2910.48 2658.09 2808.39 2770.24 3235.64 N/A 3251.26 3104.87 3187.51 3167.98 3039.68 2739.21 2835.63 2861.92 Calculated
Anticipated Consolidation of Lower Zone from t1 to t2, Sbott (ft)N/A N/A N/A 0.17 0.01 0.00 0.03 0.07 0.02 N/A 0.01 0.02 0.01 0.00 0.00 0.01 0.04 0.08 Calculated using consolidation theory (Coduto, 1999. Equation 12.20, Page 436)
Total Anticipated Consolidation from t1 to t2, Stot (ft)0.01 0.14 0.16 0.47 0.02 0.01 0.05 0.30 0.10 0.00 0.04 0.06 0.04 0.01 0.01 0.03 0.07 0.14 Calculated using consolidation theory (Coduto, 1999. Equation 12.20, Page 436)
Thickness of Saturated Tailings at t1 (ft)14.45 16.95 18.45 22.95 27.45 20.45 25.95 21.45 21.45 13.95 21.95 23.95 21.45 19.95 24.45 21.95 26.95 27.95 Calculated
Volume of Solids in Saturated Tailings at t1, Vs1, (ft3/ft2)7.75 9.42 9.80 12.34 13.82 10.29 13.10 11.38 11.03 7.20 11.19 12.18 10.96 10.06 12.32 11.08 13.61 14.18 Calculated
Volume of Voids in Saturated Tailings at t1, Vv1, (ft3/ft2)6.70 7.52 8.65 10.61 13.62 10.15 12.85 10.07 10.42 6.74 10.76 11.76 10.49 9.88 12.13 10.87 13.33 13.77 Calculated
Volume of Voids in Saturated Tailings at t2, Vv2, (ft3/ft2)6.69 7.38 8.49 10.13 13.60 10.15 12.79 9.77 10.32 6.74 10.72 11.71 10.45 9.88 12.12 10.84 13.27 13.63 Calculated based on e1 and settlement from t1 to t2
Void Ratio of Saturated Tailings at t2, e2-tailing 0.86 0.78 0.87 0.82 0.98 0.99 0.98 0.86 0.94 0.94 0.96 0.96 0.95 0.98 0.98 0.98 0.97 0.96 Calculated based on e1 and settlement from t1 to t2
Length of Longest Flow Path, Hdr-2 (ft)1.72 2.97 3.72 5.97 N/A N/A N/A 5.22 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A Calculated (assumes double drainage conditions (Lambe and Whitman, 1969. Pg 413))
Time for 90% of Consolidation to Occur, t90 (years)0.22 0.23 0.48 0.63 N/A N/A N/A 0.14 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A Calculated using consolidation theory. (Terzaghi, et al., 1996. Pages 223 - 240)
Average Time for 90% of Consolidation to Occur, t90-avg (yr)0.34 Calculated using consolidation theory. (Terzaghi, et al., 1996. Pages 223 - 240)
Maximum Time for 90% of Consolidation to Occur, t90-max (yr)0.63 Calculated using consolidation theory. (Terzaghi, et al., 1996. Pages 223 - 240)
PHASE 3 CONSOLIDATION: AFTER PLACEMENT OF FINAL COVER
Notes
t0 occurs at midpoint of interim cover placement over a given location
t1 occurs at the beginning of tailings dewatering (1/1/2009)
t2 occurs at midpoint of final cover placement over a given location
t3 occurs at 99% of consolidation due to final cover
SOIL PROPERTIES
Tailings
2.75 Specific gravity of tailings, Gs-tailing Average calculated from laboratory tests (Chen and Associates, 1987 and Western Colorado Testing, 1999)
16.2% Long-term moisture content of unsaturated tailings, w Chen and Associates, 1987. This assumption is more conservative for settlement analysis than the value used in radon modeling (results in higher vertical stress).
30%Fines content of tailings, FCtailing (%)Average calculated from entirety of laboratory testing results (Western Colorado Testing, 1999. Chen and Associates, 1987. CSM, 1978. Denison, 2009.)
0.032 Coefficient of Consolidation of Tailings (lower bound), Cv-min (ft2/day)Calculated from phase 1 model
100.29 Moist unit weight of tailings (above capillary fringe) prior to t0, γm0-tailing (pcf)Calculated
Cover Soil
118.0 Maximum dry unit weight of cover soil γcover-max (pcf)Average calculated from laboratory testing results (UWM, 2012)
100.7 Moist unit weight of cover soil at 80% relative compaction, γcover95 (pcf)Calculated
107.0 Moist unit weight of cover soil at 85% relative compaction, γcover95 (pcf)Calculated
119.6 Moist unit weight of cover soil at 95% relative compaction, γcover95 (pcf)Calculated
6.7% Long-term moisture content of cover soil, w (%)Estimated based on measured 15bar water content. (UWM, 2012)
106.0 Dry unit weight of rock mulch, γrock-dry (pcf)From most recent radon modeling (Denison, 2012)
113.1 Moist unit weight of rock mulch, γmulch-moist (pcf)Calculated based on long-term moisture content and dry unit weight
Saturated Zone
7,590,661 Total Volume of Saturated Tailings at t2 (cf)Calculated assuming and average saturated thickness of 1.05 meters over the entire footprint of the bottom of the cell
5,593.03 Phreatic Surface Elevation at t2 (ft AMSL)Calculated from total volume of saturated tailings and stage-storage curve for Cell 2
8.00 Height of Capillary Fringe (ft)Estimated zone with 90%+ saturation: based on % fines and PI. (Fredlund, Fredlund, and Houston, 2003)
5,601.03 Elevation of Top of Capillary Fringe at t2 (ft amsl)Calculated from phreatic surface and capillary fringe.
3.00 Combined Thickness of Perched Zones (ft)Assumed
Cell 2W1 Cell 2W2 Cell 2W3 Cell 2W4 2W5-C 2W4-N 2W4-S 2W3-S Cell 2 East 2E1-N 2E1-1S 2E1-2S 2W7-C 2W7-N 2W7-S 2W6-N 2W6-C 2W6-S
Elevation of Native Ground (ft)5598.50 5596.00 5594.50 5590.00 5585.50 5592.50 5587.00 5591.50 5591.50 5599.00 5591.00 5589.00 5591.50 5593.00 5588.50 5591.00 5586.00 5585.00 From subgrade topographic drawing
Elevation of Top of Tailings at t2 (ft)5613.01 5612.46 5612.82 5612.23 5613.46 5613.48 5613.40 5612.61 5616.66 5621.21 5614.31 5613.30 5613.29 5613.46 5613.47 5613.43 5613.37 5613.24 Calculated from intial tailings surface and Phase 1 & Phase 2 settlement
Elevation of Top of Interim Cover at t2 (ft)5617.51 5616.96 5616.62 5616.13 5617.06 5616.48 5616.40 5616.51 5621.66 5625.81 5621.81 5619.80 5621.29 5621.66 5619.17 5616.83 5616.37 5616.24 Calculated
Thickness of Tailings at t2 (ft)14.51 16.46 18.32 22.23 27.96 20.98 26.40 21.11 25.16 22.21 23.31 24.30 21.79 20.46 24.97 22.43 27.37 28.24 Calculated
Thickness of Interim Cover (ft)4.50 4.50 3.80 3.90 3.60 3.00 3.00 3.90 5.00 4.60 7.50 6.50 8.00 8.20 5.70 3.40 3.00 3.00 Calculated
Load Induced by Interim Cover, Δpint (psf)453.26 453.26 382.75 392.83 362.61 302.17 302.17 392.83 503.62 463.33 755.44 654.71 805.80 825.94 574.13 342.46 302.17 302.17 Calculated
Load Induced by Final Cover, Δpfinal (psf)933.49 933.49 933.49 933.49 933.49 933.49 933.49 933.49 933.49 933.49 933.49 933.49 933.49 933.49 933.49 933.49 933.49 933.49 Calculated - final cover configuration per radon modeling (Denison, 2012)
Void Ratio of Saturated Tailings at t2, e2-tailing 0.86 0.78 0.87 0.82 0.98 0.99 0.98 0.86 0.94 0.94 0.96 0.96 0.95 0.98 0.98 0.98 0.97 0.96 Calculated based on initial void ratio and Phase 1 & Phase 2 consolidation
Dry Unit Weight of Tailings at t2, γdry-2 (pcf)92.08 96.22 91.94 94.23 86.49 86.42 86.81 92.34 88.65 88.65 87.65 87.51 87.84 86.59 86.48 86.73 86.90 87.48 Calculated
Saturated Unit Weight of Tailings at t2, γsat-2 (pcf)120.99 123.63 120.91 122.37 117.44 117.39 117.65 121.16 118.82 118.81 118.18 118.09 118.30 117.50 117.44 117.59 117.70 118.07 Calculated
Compression Index of Tailings, Cc-tails 0.83 1.30 0.88 1.11 0.03 0.02 0.09 0.88 0.38 0.56 0.15 0.14 0.15 0.03 0.02 0.07 0.11 0.21 Calculated using Phase 1 settle model (or observed settlement where model is unavailable).
Coefficient of Consolidation of Tailings Cv-tails (ft2/d)0.03 0.09 0.07 0.13 N/A N/A N/A 0.50 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A Calculated (Wray, 1996. Equation 9-6, page 109)
Settlement
Phase 3 Upper Zone (Capillary Fringe)
Elevation of Top of Upper Zone at t2 (ft)5604.03 5604.03 5604.03 5604.03 5604.03 5604.03 5604.03 5604.03 5604.03 5604.03 5604.03 5604.03 5604.03 5604.03 5604.03 5604.03 5604.03 5604.03
Elevation of Bottom of Upper Zone at t2 (ft)5598.50 5596.00 5594.50 5593.03 5593.03 5593.03 5593.03 5593.03 5593.03 5599.00 5593.03 5593.03 5593.03 5593.03 5593.03 5593.03 5593.03 5593.03
Elevation of Midpoint of Upper Zone at t2 (ft)5601.26 5600.01 5599.26 5598.53 5598.53 5598.53 5598.53 5598.53 5598.53 5601.51 5598.53 5598.53 5598.53 5598.53 5598.53 5598.53 5598.53 5598.53
Effective Stress at Midpoint of Upper Zone at t2, σ1-upper' (psf)1811.14 1933.36 1962.71 2019.02 2056.33 1997.60 1991.88 2043.29 2533.60 2594.96 2542.44 2340.16 2491.97 2520.67 2268.70 2035.09 1990.14 1981.11 Calculated
Effective Stress at Midpoint of Upper Zone at t3, σ2-upper' (psf)2744.62 2866.84 2896.20 2952.51 2989.81 2931.09 2925.37 2976.77 3467.09 3528.45 3475.93 3273.65 3425.46 3454.16 3202.18 2968.58 2923.62 2914.59 Calculated
Anticipated Consolidation of Upper Zone from t2 to t3, Supper (ft)0.45 1.00 0.76 1.11 0.03 0.02 0.09 0.85 0.29 0.19 0.11 0.11 0.12 0.02 0.02 0.07 0.10 0.20 Calculated using consolidation theory (Coduto, 1999. Equation 12.20, Page 436)
Phase 3 Lower Zone (Below Phreatic Surface)
Elevation of Top of Lower Zone at t2 (ft)N/A N/A N/A 5593.03 5593.03 5593.03 5593.03 5593.03 5593.03 N/A 5593.03 5593.03 5593.03 5593.03 5593.03 5593.03 5593.03 5593.03
Elevation of Bottom of Lower Zone at t2 (ft)N/A N/A N/A 5590.00 5585.50 5592.50 5587.00 5591.50 5591.50 N/A 5591.00 5589.00 5591.50 5593.00 5588.50 5591.00 5586.00 5585.00
Elevation of Midpoint of Lower Zone at t2 (ft)N/A N/A N/A 5591.51 5589.26 5592.76 5590.01 5592.26 5592.26 N/A 5592.01 5591.01 5592.26 5593.01 5590.76 5592.01 5589.51 5589.01
Effective Stress at Midpoint of Lower Zone at t2, σ2-low' (psf)N/A N/A N/A 2782.78 2909.38 2657.75 2805.40 2754.51 3230.14 N/A 3248.94 3101.78 3185.27 3167.67 3039.14 2737.76 2831.79 2853.88 Calculated
Effective Stress at Midpoint of Lower Zone at t3, σ3-low' (psf)N/A N/A N/A 3716.27 3842.87 3591.23 3738.88 3688.00 4163.63 N/A 4182.43 4035.26 4118.76 4101.16 3972.63 3671.24 3765.28 3787.36 Calculated
Anticipated Consolidation of Middle Zone from t2 to t3, Smid (ft)N/A N/A N/A 0.23 0.01 0.00 0.04 0.09 0.03 N/A 0.02 0.03 0.01 0.00 0.01 0.01 0.05 0.11 Calculated using consolidation theory (Coduto, 1999. Equation 12.20, Page 436)
Total Anticipated Consolidation from t2 to t3, Stot (ft)0.45 1.00 0.76 1.34 0.04 0.02 0.12 0.95 0.33 0.19 0.13 0.15 0.13 0.02 0.02 0.08 0.15 0.31 Calculated using consolidation theory (Coduto, 1999. Equation 12.20, Page 436)
Thickness of Saturated Tailings at t2 (ft)5.53 8.03 9.53 14.03 18.53 11.53 17.03 12.53 12.53 5.03 13.03 15.03 12.53 11.03 15.53 13.03 18.03 19.03 Calculated
Volume of Solids in Saturated Tailings at t2, Vs2, (ft3/ft2)2.97 4.50 5.10 7.70 9.34 5.80 8.61 6.74 6.47 2.60 6.65 7.66 6.41 5.56 7.83 6.58 9.13 9.70 Calculated
Volume of Voids in Saturated Tailings at t2, Vv2, (ft3/ft2)2.56 3.53 4.42 6.32 9.19 5.72 8.41 5.79 6.05 2.43 6.37 7.36 6.11 5.46 7.70 6.44 8.90 9.33 Calculated
Volume of Voids in Saturated Tailings at t3, Vv3, (ft3/ft2)2.11 2.52 3.66 4.99 9.15 5.70 8.29 4.84 5.73 2.24 6.24 7.22 5.98 5.44 7.68 6.37 8.75 9.02 Calculated based on e1 and settlement in Phases 1 - 3
Void Ratio of Saturated Tailings at t3, e3-tailing 0.71 0.56 0.72 0.65 0.98 0.98 0.96 0.72 0.89 0.86 0.94 0.94 0.93 0.98 0.98 0.97 0.96 0.93 Calculated based on e1 and settlement in Phases 1 - 3
Total Anticipated Consolidation from t0 to t3, Stot (ft)0.97 2.19 1.47 2.83 0.08 0.04 0.22 1.96 0.67 0.38 0.32 0.34 0.34 0.06 0.05 0.14 0.28 0.56
Length of Longest Flow Path, Hdr-3 (ft)2.53 5.03 6.53 11.03 15.53 8.53 14.03 9.53 9.53 2.03 10.03 12.03 9.53 8.03 12.53 10.03 15.03 16.03 Calculated (assumes single drainage conditions)
Time for 90% of Consolidation to Occur, t90 (years)0.47 0.67 1.45 2.12 N/A N/A N/A 0.42 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A Calculated using consolidation theory. (Terzaghi, et al., 1996. Pages 223 - 240)
Average Time for 90% of Consolidation to Occur, t90-avg (years)1.03 Calculated using consolidation theory. (Terzaghi, et al., 1996. Pages 223 - 240)
Maximum Time for 90% of Consolidation to Occur, t90-max (years)2.12 Calculated using consolidation theory. (Terzaghi, et al., 1996. Pages 223 - 240)
CREEP SETTLEMENT
Notes
t0 occurs at midpoint of interim cover placement over a given location
t1 occurs at the beginning of tailings dewatering (1/1/2009)
t2 occurs at midpoint of final cover placement over a given location
t3 occurs at 99% of consolidation due to final cover
SOIL PROPERTIES
Tailings
0.020 Cα/Cc From: (Terzaghi, Peck, and Mesri, 1996. Page 110)
0.008 Average Secondary Compression Index, C -avg Calculated using the average Cc value
0.388 Average Compression Index of Tailings Calculated from Phase 1, Cc-tails Calculated using Phase 1 settlement model (using observed settlement where model is not available).
Cell 2W1 Cell 2W2 Cell 2W3 Cell 2W4 2W5-C 2W4-N 2W4-S 2W3-S Cell 2 East 2E1-N 2E1-1S 2E1-2S 2W7-C 2W7-N 2W7-S 2W6-N 2W6-C 2W6-S
Elevation of Native Ground (ft)5598.50 5596.00 5594.50 5590.00 5585.50 5592.50 5587.00 5591.50 5591.50 5599.00 5591.00 5589.00 5591.50 5593.00 5588.50 5591.00 5586.00 5585.00 From subgrade topographic drawing
Elevation of Top of Tailings at t3 (ft)5613.01 5612.46 5612.82 5612.23 5613.46 5613.48 5613.40 5612.61 5616.66 5621.21 5614.31 5613.30 5613.29 5613.46 5613.47 5613.43 5613.37 5613.24 Calculated from intial tailings surface and Phase 1 & Phase 2 settlement
Elevation of Top of Interim Cover at t3 (ft)5617.51 5616.96 5616.62 5616.13 5617.06 5616.48 5616.40 5616.51 5621.66 5625.81 5621.81 5619.80 5621.29 5621.66 5619.17 5616.83 5616.37 5616.24 Calculated
Thickness of Tailings at t3 (ft)14.51 16.46 18.32 22.23 27.96 20.98 26.40 21.11 25.16 22.21 23.31 24.30 21.79 20.46 24.97 22.43 27.37 28.24 Calculated
Thickness of Interim Cover (ft)4.50 4.50 3.80 3.90 3.60 3.00 3.00 3.90 5.00 4.60 7.50 6.50 8.00 8.20 5.70 3.40 3.00 3.00 Calculated
Thickness of Final Cover (Above Interim Cover) (ft)8.20 8.20 8.20 8.20 8.20 8.20 8.20 8.20 8.20 8.20 8.20 8.20 8.20 8.20 8.20 8.20 8.20 8.20 From Radon Modeling (Denison, 2012)
Thickness of Saturated Tailings, Including Perched Zones (ft)5.53 8.03 9.53 14.03 18.53 11.53 17.03 12.53 12.53 5.03 13.03 15.03 12.53 11.03 15.53 13.03 18.03 19.03 Calculated
Void Ratio of Saturated Tailings at t3, e3-tailing 0.71 0.56 0.72 0.65 0.98 0.98 0.96 0.72 0.89 0.86 0.94 0.94 0.93 0.98 0.98 0.97 0.96 0.93 Calculated based on initial void ratio and settlement during Phases 1 - 3
Change in Void Ratio Due to Creep Over 1,000 years, Δe 0.032 0.032 0.032 0.032 0.032 0.032 0.032 0.032 0.032 0.032 0.032 0.032 0.032 0.032 0.032 0.032 0.032 0.032 Calculated using fomula in Holtz and Kovacs, 1981. Pages 406-408
Final Void Ratio After 1,000 years, efinal 0.68 0.53 0.69 0.62 0.95 0.95 0.93 0.69 0.85 0.83 0.91 0.91 0.90 0.95 0.95 0.94 0.93 0.90 Calculated
Estimated Settlement due to 1,000 years of Creep, Screep (ft)0.10 0.16 0.18 0.27 0.30 0.18 0.27 0.23 0.21 0.09 0.21 0.25 0.21 0.18 0.25 0.21 0.29 0.31 Calculated using Holtz and Kovacs, 1981. Equation 8-4, page 413.
UNSATURATED ZONE SETTLEMENT DUE TO SEISMIC SHAKING
0.15 Peak Horizontal Acceleration, PHA (g) Technical Memorandum: Site-Specific Probabilistic Seismic Hazard Analysis White Mesa Uranium Facility Blanding, Utah. (MWH, 2012)
6.00 Earthquake Magnitude, m Technical Memorandum: Site-Specific Probabilistic Seismic Hazard Analysis White Mesa Uranium Facility Blanding, Utah. (MWH, 2012)
51.50 Site-Source Distance, r (km) Mean distance from site for earthquakes contributing to the probabilistic hazard at the 9,900 year return period. (Technical Memorandum: Site-Specific Probabilistic Seismic Hazard Analysis White Mesa Uranium Facility Blanding, Utah. (MWH, 2012))
13.25 Equivalent Number of Uniform Strain Cycles, N Calculated (Stewart and Whang, 2003. Equation 6)
2.00 SPT blow count for tailings, Nm (blows/foot)(uncorrected)Conservatively assumed a blow count of 2 which is representative of very loose granular soils. Range of uncorrected (SPT) blow counts for medium dense fine granular soils with wet unit weights of 110 to 130 pcf is 7 to 15 (Bowles, 1988).
108.56 Mass Unit Weight of Soil, γ (pcf)Calculated over the upper 12m of the final tailings cell configuration
1.74 Mass Density of Soil, ρ (g/cm3)Calculated over the upper 12m of the final tailings cell configuration
11,072 Maximum Shear Modulus, Gmax Calculated based on Shear Wave Velocity and Mass Density of Soil (Stewart and Whang, 2003. Page 7)
Calculated Range of Values for Average Soil Shear Wave Velocity in Upper 12m, Vs-12
261.63 Shear wave velocity in the upper 12m, Vs-12 (ft/sec)Calculated based on the blow count for the tailings. (USACE, 1987. Equation 30) Originally from Seed and Idriss 1983 - Developed for sands and silty sands
347.12 Shear wave velocity in the upper 12m, Vs-12 (ft/sec)Calculated based on the blow count for the tailings. (USACE, 1987. Equation 21) Originally from Ohba and Toriuma 1973 - Developed for alluvial materials near Osaka, Japan
349.88 Shear wave velocity in the upper 12m, Vs-12 (ft/sec)Calculated based on the blow count for the tailings. (USACE, 1987. Equation 23) Originally from Ohsaki 1963 - Developed for Japanese sands.
267.83 Shear wave velocity in the upper 12m, Vs-12 (ft/sec)Calculated based on the blow count for the tailings and specified parameters for "intermediate" soils. (USACE, 1987. Equation 24) Originally from Ohsaki and Iwasaki 1973 - Applies to multiple soil types, .
356.38 Shear wave velocity in the upper 12m, Vs-12 (ft/sec)Calculated based on the blow count for the tailings. (USACE, 1987. Table 4, Equation 1) Originally from Ohta and Goto 1978 - Not dependent on soil type
358.18 Shear wave velocity in the upper 12m, Vs-12 (ft/sec)Calculated based on the blow count for the tailings and depth. (USACE, 1987. Table 4, Equation 5) Originally from Ohta and Goto 1978 - not dependent on soil type
327.60 Shear wave velocity in the upper 12m, Vs-12 (ft/sec)Calculated based on the blow count for the tailings. (USACE, 1987. Equation 31) Originally from Imai and Yoshimura 1970 - Independent of soil type
379.35 Shear wave velocity in the upper 12m, Vs-12 (ft/sec)Calculated based on the blow count for the tailings. (USACE, 1987. Equation 32) Originally from Imai and Yoshimura 1975 - Independent of soil type
373.66 Shear wave velocity in the upper 12m, Vs-12 (ft/sec)Calculated based on the blow count for the tailings. (USACE, 1987. Equation 33) Originally from Imai, Fumotot, and Yokota 1975 - Independent of soil type
235.51 Shear wave velocity in the upper 12m, Vs-12 (ft/sec)Calculated based on the blow count for the tailings. (USACE, 1987. Equation 34) Originally from Imai and Tonuchi, 1982 - Independent of soil type
395.32 Shear wave velocity in the upper 12m, Vs-12 (ft/sec)Calculated based on the blow count for the tailings. (USACE, 1987. Table 4, Equation 12) Originally from Imari and Tonouchi 1982 - For all soils
332.04 Average Shear wave velocity in the upper 12m, Vs-12 (ft/sec)Calculated
101.20 Average Shear wave velocity in the upper 12m, Vs-12 (m/sec)Calculated
79.74 Value Used for Average Soil Shear Wave Velocity in Upper
12m, Vs-12 (m/s)Calculated based on the blow count for the tailings. (USACE, 1987. Equation 30) Originally from Seed and Idriss 1983 - Developed for sands and silty sands
Cell 2W1 Cell 2W2 Cell 2W3 Cell 2W4 2W5-C 2W4-N 2W4-S 2W3-S Cell 2 East 2E1-N 2E1-1S 2E1-2S 2W7-C 2W7-N 2W7-S 2W6-N 2W6-C 2W6-S
Elevation of Native Ground (ft)5598.50 5596.00 5594.50 5590.00 5585.50 5592.50 5587.00 5591.50 5591.50 5599.00 5591.00 5589.00 5591.50 5593.00 5588.50 5591.00 5586.00 5585.00 From subgrade topographic drawing
Elevation of Top of Tailings at t3 (ft)5612.56 5611.46 5612.06 5610.89 5613.42 5613.46 5613.28 5611.66 5616.33 5621.02 5614.18 5613.16 5613.16 5613.44 5613.45 5613.36 5613.22 5612.94 Calculated from intial tailings surface and Phase 1 - 3 settlement
Elevation of Top of Interim Cover at t3 (ft)5617.06 5615.96 5615.86 5614.79 5617.02 5616.46 5616.28 5615.56 5621.33 5625.62 5621.68 5619.66 5621.16 5621.64 5619.15 5616.76 5616.22 5615.94 Calculated
Thickness of Tailings at t3 (ft)14.06 15.46 17.56 20.89 27.92 20.96 26.28 20.16 24.83 22.02 23.18 24.16 21.66 20.44 24.95 22.36 27.22 27.94 Calculated
Thickness of Interim Cover (ft)4.50 4.50 3.80 3.90 3.60 3.00 3.00 3.90 5.00 4.60 7.50 6.50 8.00 8.20 5.70 3.40 3.00 3.00 Calculated
Elevation of Top of Final Cover at t3 (ft)5625.26 5624.16 5624.06 5622.99 5625.22 5624.66 5624.48 5623.76 5629.53 5633.82 5629.88 5627.86 5629.36 5629.84 5627.35 5624.96 5624.42 5624.14 Calculated
Load Induced by Interim Cover, Δpint (psf)453.26 453.26 382.75 392.83 362.61 302.17 302.17 392.83 503.62 463.33 755.44 654.71 805.80 825.94 574.13 342.46 302.17 302.17 Calculated
Load Induced by Final Cover, Δpfinal (psf)933.49 933.49 933.49 933.49 933.49 933.49 933.49 933.49 933.49 933.49 933.49 933.49 933.49 933.49 933.49 933.49 933.49 933.49 Calculated
Elevation of Settlement Measurement (ft) 5598.50 5596.00 5594.50 5593.04 5593.04 5593.04 5593.04 5593.04 5593.04 5599.00 5593.04 5593.04 5593.04 5593.04 5593.04 5593.04 5593.04 5593.04 Just above Phreatic surface (or at contact with native ground if no phreatic surface)
Depth of Settlement Measurement, z (ft)26.76 28.16 29.56 29.95 32.18 31.63 31.44 30.72 36.49 34.82 36.84 34.82 36.32 36.81 34.31 31.92 31.39 31.10 Calculated
Depth of Settlement Measurement, z (m)8.16 8.58 9.01 9.13 9.81 9.64 9.58 9.36 11.12 10.61 11.23 10.61 11.07 11.22 10.46 9.73 9.57 9.48 Calculated
Coefficient a1 -13.24 -13.24 -13.24 -13.24 -13.24 -13.24 -13.24 -13.24 -13.24 -13.24 -13.24 -13.24 -13.24 -13.24 -13.24 -13.24 -13.24 -13.24 Calculated (Stewart and Whang, 2003. Page 3)
Coefficient a2 17.66 17.47 17.30 17.26 17.05 17.10 17.12 17.18 16.77 16.86 16.75 16.86 16.78 16.75 16.90 17.08 17.12 17.15 Calculated (Stewart and Whang, 2003. Page 3)
Coefficient a3 38.83 38.83 38.83 38.83 38.83 38.83 38.83 38.83 38.83 38.83 38.83 38.83 38.83 38.83 38.83 38.83 38.83 38.83 Calculated (Stewart and Whang, 2003. Page 3)
Stress Reduction Factor, rd (from Stewart and Whang, 2003)0.38 0.37 0.36 0.35 0.34 0.34 0.34 0.35 0.32 0.33 0.32 0.33 0.32 0.32 0.33 0.34 0.34 0.35 Calculated (Stewart and Whang, 2003. Equation 5a)
Overburden Pressure, σ0 (psf)2849.52 3054.15 3212.02 3293.34 3477.36 3420.94 3404.14 3360.99 3921.41 3642.48 3952.22 3748.59 3901.14 3943.58 3691.54 3452.11 3399.40 3373.45 Calculated
Overburden Pressure, σ0 (g/cm2)1394.31 1494.45 1571.70 1611.49 1701.53 1673.92 1665.70 1644.59 1918.81 1782.32 1933.89 1834.24 1908.89 1929.66 1806.33 1689.18 1663.38 1650.69 Calculated
γeff*Geff/Gmax 0.0005 0.0005 0.0005 0.0005 0.0005 0.0005 0.0005 0.0005 0.0006 0.0005 0.0006 0.0005 0.0005 0.0006 0.0005 0.0005 0.0005 0.0005 Calculated (Stewart and Whang, 2003. Equation 4)
Variation of Shear Strain Amplitude, γeff (%)1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 From Stewart and Whang, 2003. Figure 3
Vertical Strain for 15 cycles of shaking, v,n=15 (%)1.30 1.30 1.30 1.30 1.30 1.30 1.30 1.30 1.30 1.30 1.30 1.30 1.30 1.30 1.30 1.30 1.30 1.30 From Stewart and Whang, 2003. Figure 5
CN 0.90 0.90 0.90 0.90 0.90 0.90 0.90 0.90 0.90 0.90 0.90 0.90 0.90 0.90 0.90 0.90 0.90 0.90 From Stewart and Whang, 2003. Figure 4
Vertical Strain , (%)1.62 1.62 1.62 1.62 1.62 1.62 1.62 1.62 1.62 1.62 1.62 1.62 1.62 1.62 1.62 1.62 1.62 1.62 From Stewart and Whang, 2003. Pages 2 and 7
Settlement, S (ft)0.43 0.46 0.48 0.49 0.52 0.51 0.51 0.50 0.59 0.56 0.60 0.56 0.59 0.60 0.56 0.52 0.51 0.50 Calculated (volumetric strain applied to entire soil column)
NOTES
t0 occurs at midpoint of interim cover placement over a given location
t1 occurs at the beginning of tailings dewatering (1/1/2009)
t2 occurs at midpoint of final cover placement over a given location
t3 occurs at 99% of consolidation due to final cover
It is assumed that there is an additional 3 feet of perched zones of saturation above the capillary fringe.
REFERENCES
Bowles, J., 1988. Foundation Analysis and Design, Fourth Edition. McGraw-Hill, Inc. New York.
Bowles, J., 1992. Engineering Properties of Soils, Fourth Edition. McGraw-Hill, Inc. New York.
Chen and Associates, Inc., 1987. Physical Soil Data, White Mesa Project, Blanding Utah, Report prepared for Energy
Fuels Nuclear, Inc.
Coduto, D. P., 1999. Geotechnical Engineering Principles and Practices. Prentice-Hall, Inc. New Jersey.
Denison Mines (USA) Corp. (Denison), 2012. Responses to Interrogatories – Round 1 for Reclamation Plan,
Revision 5.0, March 12. Attachment H - Supporting Documentation for Interrogatory 12/1: Revised Appendix C,
Radon Emanation Modeling, to the Updated Tailings Cover Design Report (Appendix D of Reclamation Plan,
Fredlund, M.D., Fredlund, D.G., Houston, S.L., and Houston, W., 2003. Assessment of Unsaturated Soil Properties
for Seepage Modeling Through Tailings and Mine Wastes, Proceedings of Tailings and Mine Waste 2003.
Holtz, R.D. and Kovacs, W.D., 1981. An Introduction to Geotechnical Engineering. Prentice Hall, Inc. New Jersey
Lambe, T. W., and Whitman, R. V., 1969. Soil Mechanics. John Wiley and Sons, New York.
MWH, 2011. White Mesa Mill Updated Tailings Cover Design Report. Prepared for Denison Mines (USA) Corp.
September 2011.
MWH, 2012. Technical Memorandum: Site-Specific Probabilistic Seismic Hazard Analysis for the White Mesa
Uranium Facility. Blanding, Utah. September, 2011.
Stewart, L. P., and D. H. Whang, 2003. Simplified Procedure to Estimate Ground Settlement from Seismic
Compression in Compacted Soils. 2003 Pacific Conference on Earthquake Engineering.
Terzaghi, K., R. Peck, and G. Mesri, 1996. Soil Mechanics in Engineering Practice, Third Edition. John Wiley and
Sons, Inc. New York
United States Army Corps of Engineers (USACE), 1987. Examination of Existing Shear Wave Velocity and Shear
Modulus Correlations in Soils. Miscellaneous Paper GL-87-22. Department of the Army, Washington, DC.
University of Wisconsin-Madison (UWM), Wisconsin Geotechnics Laboratory, 2012. Compaction and Hydraulic
Properties of Soils from Banding, Utah. Geotechnics Report NO. 12-41 by C.H. Benson and X. Wang. July 24.
Western Colorado Testing, Inc., 1999. Report of Soil Sample Testing of Tailings Collected from Cell 2 and Cell 3,
Prepared for International Uranium (USA) Corporation. May 4.
Wray, W. K., 1986. Measuring Engineering Properties of Soils. Prentice-Hall, Inc., New Jersey.
5618.0
5618.2
5618.4
5618.6
5618.8
5619.0
5619.2
5619.4
5619.6
5619.8
5620.0
5620.2
5620.4
5620.6
5620.8
5621.0
5/
1
7
/
1
9
8
9
5/
1
7
/
1
9
9
0
5/
1
7
/
1
9
9
1
5/
1
6
/
1
9
9
2
5/
1
7
/
1
9
9
3
5/
1
7
/
1
9
9
4
5/
1
7
/
1
9
9
5
5/
1
6
/
1
9
9
6
5/
1
7
/
1
9
9
7
5/
1
7
/
1
9
9
8
5/
1
7
/
1
9
9
9
5/
1
6
/
2
0
0
0
5/
1
7
/
2
0
0
1
5/
1
7
/
2
0
0
2
5/
1
7
/
2
0
0
3
5/
1
6
/
2
0
0
4
5/
1
7
/
2
0
0
5
5/
1
7
/
2
0
0
6
5/
1
7
/
2
0
0
7
5/
1
6
/
2
0
0
8
El
e
v
a
t
i
o
n

(
f
t
)
Date
Phase 1 Settlement at 2W1
2W1 (Measured)
2W1 Model - Primary Consolidation Only
2W1 Model - Primary and Secondary Consolidation
5620.0
5620.2
5620.4
5620.6
5620.8
5621.0
5621.2
5621.4
5621.6
5621.8
5622.0
5622.2
5622.4
5622.6
5622.8
5623.0
8/
2
8
/
1
9
9
1
8/
2
7
/
1
9
9
2
8/
2
7
/
1
9
9
3
8/
2
7
/
1
9
9
4
8/
2
8
/
1
9
9
5
8/
2
7
/
1
9
9
6
8/
2
7
/
1
9
9
7
8/
2
7
/
1
9
9
8
8/
2
8
/
1
9
9
9
8/
2
7
/
2
0
0
0
8/
2
7
/
2
0
0
1
8/
2
7
/
2
0
0
2
8/
2
8
/
2
0
0
3
8/
2
7
/
2
0
0
4
8/
2
7
/
2
0
0
5
8/
2
7
/
2
0
0
6
8/
2
8
/
2
0
0
7
8/
2
7
/
2
0
0
8
El
e
v
a
t
i
o
n

(
f
t
)
Date
Phase 1 Settlement at 2W2
2W2 (Measured)
2W2 Model - Primary Consolidation Only
2W2 Model - Primary and Secondary Consolidation
5617.0
5617.2
5617.4
5617.6
5617.8
5618.0
5618.2
5618.4
5618.6
5618.8
5619.0
5619.2
5619.4
5619.6
5619.8
5620.0
8/
2
8
/
1
9
9
1
8/
2
7
/
1
9
9
2
8/
2
7
/
1
9
9
3
8/
2
7
/
1
9
9
4
8/
2
8
/
1
9
9
5
8/
2
7
/
1
9
9
6
8/
2
7
/
1
9
9
7
8/
2
7
/
1
9
9
8
8/
2
8
/
1
9
9
9
8/
2
7
/
2
0
0
0
8/
2
7
/
2
0
0
1
8/
2
7
/
2
0
0
2
8/
2
8
/
2
0
0
3
8/
2
7
/
2
0
0
4
8/
2
7
/
2
0
0
5
8/
2
7
/
2
0
0
6
8/
2
8
/
2
0
0
7
8/
2
7
/
2
0
0
8
El
e
v
a
t
i
o
n

(
f
t
)
Date
Phase 1 Settlement at 2W3
2W3 (Measured)
2W3 Model - Primary Consolidation Only
2W3 Model - Primary and Secondary Consolidation
5616.0
5616.2
5616.4
5616.6
5616.8
5617.0
5617.2
5617.4
5617.6
5617.8
5618.0
5618.2
5618.4
5618.6
5618.8
5619.0
7/
2
3
/
1
9
9
1
7/
2
2
/
1
9
9
2
7/
2
2
/
1
9
9
3
7/
2
2
/
1
9
9
4
7/
2
3
/
1
9
9
5
7/
2
2
/
1
9
9
6
7/
2
2
/
1
9
9
7
7/
2
2
/
1
9
9
8
7/
2
3
/
1
9
9
9
7/
2
2
/
2
0
0
0
7/
2
2
/
2
0
0
1
7/
2
2
/
2
0
0
2
7/
2
3
/
2
0
0
3
7/
2
2
/
2
0
0
4
7/
2
2
/
2
0
0
5
7/
2
2
/
2
0
0
6
7/
2
3
/
2
0
0
7
7/
2
2
/
2
0
0
8
El
e
v
a
t
i
o
n

(
f
t
)
Date
Phase 1 Settlement at 2W4
2W4 (Measured)
2W4 Model - Primary Consolidation Only
2W4 Model - Primary and Secondary Consolidation
5616.0
5616.2
5616.4
5616.6
5616.8
5617.0
5617.2
5617.4
5617.6
5617.8
5618.0
5618.2
5618.4
5618.6
5618.8
5619.0
4/
4
/
1
9
9
9
4/
3
/
2
0
0
0
4/
3
/
2
0
0
1
4/
3
/
2
0
0
2
4/
4
/
2
0
0
3
4/
3
/
2
0
0
4
4/
3
/
2
0
0
5
4/
3
/
2
0
0
6
4/
4
/
2
0
0
7
4/
3
/
2
0
0
8
El
e
v
a
t
i
o
n

(
f
t
)
Date
Phase 1 Settlement at 2W3-S
2W3-S (Measured)
2W3-S Model - Primary Consolidation Only
2W3-S Model - Primary and Secondary Consolidation
5617.0
5617.2
5617.4
5617.6
5617.8
5618.0
5618.2
5618.4
5618.6
5618.8
5619.0
5619.2
5619.4
5619.6
5619.8
5620.0
8/
2
6
/
2
0
0
5
8/
2
6
/
2
0
0
6
8/
2
6
/
2
0
0
7
8/
2
5
/
2
0
0
8
El
e
v
a
t
i
o
n

(
f
t
)
Date
Phase 1 Settlement at 2W5-C
2W5-C (Measured)
2W5-C Model - Secondary Consolidation Only
5618.0
5618.2
5618.4
5618.6
5618.8
5619.0
5619.2
5619.4
5619.6
5619.8
5620.0
5620.2
5620.4
5620.6
5620.8
5621.0
8/
2
6
/
2
0
0
5
8/
2
6
/
2
0
0
6
8/
2
6
/
2
0
0
7
8/
2
5
/
2
0
0
8
El
e
v
a
t
i
o
n

(
f
t
)
Date
Phase 1 Settlement at 2W4-N
2W4-N (Measured)
2W4-N Model - Secondary Consolidation Only
5615.0
5615.2
5615.4
5615.6
5615.8
5616.0
5616.2
5616.4
5616.6
5616.8
5617.0
5617.2
5617.4
5617.6
5617.8
5618.0
8/
2
6
/
2
0
0
5
8/
2
6
/
2
0
0
6
8/
2
6
/
2
0
0
7
8/
2
5
/
2
0
0
8
El
e
v
a
t
i
o
n

(
f
t
)
Date
Phase 1 Settlement at 2W4-S
2W4-S (Measured)
2W4-S Model - Secondary Consolidation Only
5623.0
5623.2
5623.4
5623.6
5623.8
5624.0
5624.2
5624.4
5624.6
5624.8
5625.0
5625.2
5625.4
5625.6
5625.8
5626.0
6/
1
6
/
1
9
8
9
6/
1
6
/
1
9
9
0
6/
1
6
/
1
9
9
1
6/
1
5
/
1
9
9
2
6/
1
6
/
1
9
9
3
6/
1
6
/
1
9
9
4
6/
1
6
/
1
9
9
5
6/
1
5
/
1
9
9
6
6/
1
6
/
1
9
9
7
6/
1
6
/
1
9
9
8
6/
1
6
/
1
9
9
9
6/
1
5
/
2
0
0
0
6/
1
6
/
2
0
0
1
6/
1
6
/
2
0
0
2
6/
1
6
/
2
0
0
3
6/
1
5
/
2
0
0
4
6/
1
6
/
2
0
0
5
6/
1
6
/
2
0
0
6
6/
1
6
/
2
0
0
7
6/
1
5
/
2
0
0
8
El
e
v
a
t
i
o
n

(
f
t
)
Date
Phase 1 Settlement at Cell 2 East
Cell 2 East (Measured)
Cell 2 East Model - Secondary Consolidation Only
5626.0
5626.2
5626.4
5626.6
5626.8
5627.0
5627.2
5627.4
5627.6
5627.8
5628.0
5628.2
5628.4
5628.6
5628.8
5629.0
9/
3
/
1
9
9
8
9/
3
/
1
9
9
9
9/
2
/
2
0
0
0
9/
2
/
2
0
0
1
9/
3
/
2
0
0
2
9/
3
/
2
0
0
3
9/
2
/
2
0
0
4
9/
2
/
2
0
0
5
9/
3
/
2
0
0
6
9/
3
/
2
0
0
7
9/
2
/
2
0
0
8
El
e
v
a
t
i
o
n

(
f
t
)
Date
Phase 1 Settlement at 2E1-N
2E1-N (Measured)
2E1-N Model - Secondary Consolidation Only
5622.0
5622.2
5622.4
5622.6
5622.8
5623.0
5623.2
5623.4
5623.6
5623.8
5624.0
5624.2
5624.4
5624.6
5624.8
5625.0
9/
3
/
1
9
9
8
9/
3
/
1
9
9
9
9/
2
/
2
0
0
0
9/
2
/
2
0
0
1
9/
3
/
2
0
0
2
9/
3
/
2
0
0
3
9/
2
/
2
0
0
4
9/
2
/
2
0
0
5
9/
3
/
2
0
0
6
9/
3
/
2
0
0
7
9/
2
/
2
0
0
8
El
e
v
a
t
i
o
n

(
f
t
)
Date
Phase 1 Settlement at 2E1-1S
2E1-1S (Measured)
2E1-1S Model - Secondary Consolidation Only
5618.0
5618.2
5618.4
5618.6
5618.8
5619.0
5619.2
5619.4
5619.6
5619.8
5620.0
5620.2
5620.4
5620.6
5620.8
5621.0
9/
3
/
1
9
9
8
9/
3
/
1
9
9
9
9/
2
/
2
0
0
0
9/
2
/
2
0
0
1
9/
3
/
2
0
0
2
9/
3
/
2
0
0
3
9/
2
/
2
0
0
4
9/
2
/
2
0
0
5
9/
3
/
2
0
0
6
9/
3
/
2
0
0
7
9/
2
/
2
0
0
8
El
e
v
a
t
i
o
n

(
f
t
)
Date
Phase 1 Settlement at 2E1-2S
2E1-2S (Measured)
2E1-2S Model - Secondary Consolidation Only
5621.0
5621.2
5621.4
5621.6
5621.8
5622.0
5622.2
5622.4
5622.6
5622.8
5623.0
5623.2
5623.4
5623.6
5623.8
5624.0
5/
4
/
1
9
9
9
5/
3
/
2
0
0
0
5/
3
/
2
0
0
1
5/
3
/
2
0
0
2
5/
4
/
2
0
0
3
5/
3
/
2
0
0
4
5/
3
/
2
0
0
5
5/
3
/
2
0
0
6
5/
4
/
2
0
0
7
5/
3
/
2
0
0
8
El
e
v
a
t
i
o
n

(
f
t
)
Date
Phase 1 Settlement at 2W7-C
2W7-C (Measured)
2W7-C Model - Secondary Consolidation Only
5620.0
5620.2
5620.4
5620.6
5620.8
5621.0
5621.2
5621.4
5621.6
5621.8
5622.0
5622.2
5622.4
5622.6
5622.8
5623.0
8/
2
6
/
2
0
0
5
8/
2
6
/
2
0
0
6
8/
2
6
/
2
0
0
7
8/
2
5
/
2
0
0
8
El
e
v
a
t
i
o
n

(
f
t
)
Date
Phase 1 Settlement at 2W7-N
2W7-N (Measured)
2W7-N Model - Secondary Consolidation Only
5619.0
5619.2
5619.4
5619.6
5619.8
5620.0
5620.2
5620.4
5620.6
5620.8
5621.0
5621.2
5621.4
5621.6
5621.8
5622.0
8/
2
6
/
2
0
0
5
8/
2
6
/
2
0
0
6
8/
2
6
/
2
0
0
7
8/
2
5
/
2
0
0
8
El
e
v
a
t
i
o
n

(
f
t
)
Date
Phase 1 Settlement at 2W7-S
2W7-S (Measured)
2W7-S Model - Secondary Consolidation Only
5619.0
5619.2
5619.4
5619.6
5619.8
5620.0
5620.2
5620.4
5620.6
5620.8
5621.0
5621.2
5621.4
5621.6
5621.8
5622.0
8/
2
6
/
2
0
0
5
8/
2
6
/
2
0
0
6
8/
2
6
/
2
0
0
7
8/
2
5
/
2
0
0
8
El
e
v
a
t
i
o
n

(
f
t
)
Date
Phase 1 Settlement at 2W6-N
2W6-N (Measured)
2W6-N Model - Secondary Consolidation Only
5617.0
5617.2
5617.4
5617.6
5617.8
5618.0
5618.2
5618.4
5618.6
5618.8
5619.0
5619.2
5619.4
5619.6
5619.8
5620.0
8/
2
6
/
2
0
0
5
8/
2
6
/
2
0
0
6
8/
2
6
/
2
0
0
7
8/
2
5
/
2
0
0
8
El
e
v
a
t
i
o
n

(
f
t
)
Date
Phase 1 Settlement at 2W6-C
2W6-C (Measured)
2W6-C Model - Secondary Consolidation Only
5615.0
5615.2
5615.4
5615.6
5615.8
5616.0
5616.2
5616.4
5616.6
5616.8
5617.0
5617.2
5617.4
5617.6
5617.8
5618.0
8/
2
6
/
2
0
0
5
8/
2
6
/
2
0
0
6
8/
2
6
/
2
0
0
7
8/
2
5
/
2
0
0
8
El
e
v
a
t
i
o
n

(
f
t
)
Date
Phase 1 Settlement at 2W6-S
2W6-S (Measured)
2W6-S Model - Secondary Consolidation Only

ATTACHMENT F

SUPPORTING DOCUMENTATION FOR INTERROGATORY 07/1:

UPDATED LIQUEFACTION ANALYSES

Client: Denison Mines Job No.: 1009740
Project: White Mesa Mill Reclamation Date: 8/9/2012
Detail: Liquefaction Analysis of Reclaimed Cells Computed By: SAM and TMS
Analysis based on Youd, T.L. et al., 2001. Liquefaction Resistance of Soils: Summary report from the 1996 NCEER and 1998 NCEER/NSF Workshops of
Evaluation of Liquefaction Resistance of Soils, Journal of Geotechnical and Geoenvironmental Engineering, October.
Note: Reference list at the bottom of this page.
SITE-WIDE DATA
6 Earthquake magnitude, Mw Technical Memorandum: Site-Specific Probabilistic Seismic Hazard Analysis White Mesa Uranium Facility Blanding, Utah. (MWH, 2012)
1.77 Magnitude Scaling Factor, MSF Youd, et al. 2001. Equation 24.
0.15 Peak horizonal acceleration at ground surface, amax/g Technical Memorandum: Site-Specific Probabilistic Seismic Hazard Analysis White Mesa Uranium Facility Blanding, Utah. (MWH, 2012)
90 Dry unit weight of tailings, γd-tailing (pcf)
14.14 Dry unit weight of tailings, d-tailing (kN/m3)Calculated
95.40 Moist unit weight of tailings, γm-tailing (pcf)Calculated based on 6% water content
14.99 Moist unit weight of tailings, m-tailing (kN/m3)Calculated
120.3 Saturated unit weight of tailings, γsat-tailing (pcf)Calculated based on dry unit weight, specific gravity, and porosity presented in Denison, 2012.
18.90 Saturated unit weight of tailings, sat-tailing (kN/m3)Calculated
2 SPT blow count for tailings, Nm (blows/foot)(uncorrected)Conservatively assumed a blow count of 2 which is representative of very loose granular soils. Range of uncorrected (SPT) blow counts for medium dense
fine granular soils with wet unit weights of 110 to 130 pcf is 7 to 15 (Bowles, 1988).
2.75 Specific gravity of tailings, Gs-tailing Average calculated from laboratory tests (Chen and Associates, 1987 and Western Colorado Testing, 1999)
0.90 Void ratio of tailings, e Calculated
6.0% Moisture content of unsaturated tailings, w The long-term moisture content value for the tailings is assumed to be 6 percent, per NRC Regulatory Guide 3.64 (NRC, 1989), and is consistent with the
radon modeling (Denison, 2012).
18.2% Percent saturation of unsaturated tailings, S (%)Calculated
30%Fines content of tailings, FCtailing (%)Average calculated from entirety of laboratory testing results (Western Colorado Testing, 1999. Chen and Associates, 1987. CSM, 1978. Denison, 2009.)
118.0 Maximum dry unit weight of cover soil γcover-max (pcf)The maximum dry unit weight of the cover soils were average values estimated from laboratory testing results (UWM, 2012).
18.54 Maximum dry unit weight of cover soil γcover-max (kN/m3)Calculated
100.7 Moist unit weight of cover soil at 80% relative compaction, γcover95 (pcf)Calculated
15.82 Moist unit weight of cover soil at 80% relative compaction, γcover95 (kN/m3)Calculated
107.0 Moist unit weight of cover soil at 85% relative compaction, γcover95 (pcf)Calculated
16.81 Moist unit weight of cover soil at 85% relative compaction, γcover95 (kN/m3)Calculated
119.6 Moist unit weight of cover soil at 95% relative compaction, γcover95 (pcf)Calculated
18.79 Moist unit weight of cover soil at 95% relative compaction, γcover95 (kN/m3)Calculated
6.7% Natural (long-term) moisture content of cover soil, w (%)The long-term water content of the cover soils were average values estimated from laboratory testing results (UWM, 2012).
1,248 Normal stress induced by cover loading of Cell 2, σv (psf)
59.77 Normal stress induced by cover loading of Cell 2, σv (kN/m2)
1,165 Normal stress induced by cover loading of Cell 3, σv (psf)
55.76 Normal stress induced by cover loading of Cell 3, σv (kN/m2)
1,117 Normal stress induced by cover loading of Cells 4a and 4b, σv (psf)
53.47 Normal stress induced by cover loading of Cells 4a and 4b, σv (kN/m2)
Cell 2 Cover Thickness Cover thicknesses from Denison, 2012.
0.5 Rock mulch/topsoil (ft)
3.5 Random fill at 85% compaction
4.7 Random fill at 95% compaction (ft)
2.5 Grading layer, random fill at 80% compaction (ft)
11.2 Total cover thickness (ft)
3.41 Total cover thickness (m)
CELL 2
Tailings:
5613.5 Tailings Surface elevation (ft)
5581 Lowest native ground elevation (ft)
5593.03 Water surface elevation (ft)
32.5 Tailings Thickness (ft)From Table F.1 in Appendix F to the Updated Tailings Cover Design Report (MWH, 2011).
9.91 Tailings Thickness (m)Calculated from Table F.1 in Appendix F to the Updated Tailings Cover Design Report (MWH, 2011).
12.03 Max Saturated Thickness (ft)From settlement spreadsheet (Denison, 2012)
3.67 Max Saturated Thickness (m)From settlement spreadsheet (Denison, 2012)
Note: For tailings Cell 2, phreatic surface is assumed to be flat, at elevation 5593.03 ft amsl.
Elevation (ft)
Depth from top of
cover (ft)
Depth from top
of cover (m)σvo (psf)σvo (kN/m2)σ'vo (psf)σ'vo (kN/m2) CN (N1)60 (N1)60CS rd CSR CRR7.5 FS
5593 31.7 9.66 3,205 153 3,203 153 0.81 2.81 4.71 1.15432 8.0 0.911 0.089 0.096 1.90 Top of water surface
5590 34.7 10.58 3,566 171 3,377 162 0.79 2.79 4.71 1.15432 7.9 0.893 0.092 0.095 1.83
5587 37.7 11.49 3,927 188 3,550 170 0.76 2.76 4.71 1.15432 7.9 0.870 0.094 0.095 1.79
5584 40.7 12.40 4,288 205 3,724 178 0.74 2.74 4.71 1.15432 7.9 0.845 0.095 0.095 1.77
5581 43.7 13.32 4,648 223 3,898 187 0.72 2.72 4.71 1.15432 7.8 0.817 0.095 0.095 1.76 Native ground elevation
Cell 3 Cover Thickness Cover thicknesses from Denison, 2012.
0.5 Rock mulch/topsoil (ft)
3.5 Random fill at 85% compaction
4.0 Random fill at 95% compaction (ft)
2.5 Grading layer, random fill at 80% compaction (ft)
10.5 Total cover thickness (ft)
3.20 Total cover thickness (m)
CELL 3
Tailings:
36.97 Phreatic Surface depth from top of cover
49 Depth from top of cover to lowest point on native ground
38.5 Tailings Thickness (ft)From Table F.1 in Appendix F to the Updated Tailings Cover Design Report (MWH, 2011).
11.73 Tailings Thickness (m)Calculated from Table F.1 in Appendix F to the Updated Tailings Cover Design Report (MWH, 2011).
12.03 Max Saturated Thickness (ft)Assumed to be the same as for Cell 2
3.67 Max Saturated Thickness (m)Assumed to be the same as for Cell 2
Note: For tailings Cell 3, phreatic surface is assumed to be flat at an elevation 12 ft above the lowest point.
Depth from top
of Cover (ft)
Depth from top of
Cover (m)σvo (psf)σvo (kN/m2)σ'vo (psf)σ'vo (kN/m2) CN (N1)60 (N1)60CS rd CSR CRR7.5 FS
37.0 11.28 3,693 177 3,692 176.8 0.75 2.75 4.71 1.15432 7.9 0.876 0.085 0.095 1.97 Top of water surface
40.0 12.19 4,054 194 3,865 185.1 0.73 2.73 4.71 1.15432 7.9 0.851 0.087 0.095 1.93
43.0 13.11 4,415 211 4,039 193.4 0.71 2.71 4.71 1.15432 7.8 0.823 0.088 0.095 1.91
46.0 14.02 4,776 229 4,213 201.7 0.69 2.69 4.71 1.15432 7.8 0.794 0.088 0.094 1.90
49.0 14.93 5,137 246 4,386 210.0 0.67 2.67 4.71 1.15432 7.8 0.763 0.087 0.094 1.91 Native ground elevation
Cells 4a and 4b Cover Thickness Cover thicknesses from Denison, 2012.
0.5 Rock mulch/topsoil (ft)
3.5 Random fill at 85% compaction
3.6 Random fill at 95% compaction (ft)
2.5 Grading layer, random fill at 80% compaction (ft)
10.1 Total cover thickness (ft)
3.08 Total cover thickness (m)
CELL 4a/4b
Tailings:
40.5 Tailings Thickness (ft)From Table F.1 in Appendix F to the Updated Tailings Cover Design Report (MWH, 2011).
12.34 Tailings Thickness (m)Calculated from Table F.1 in Appendix F to the Updated Tailings Cover Design Report (MWH, 2011).
0.33 Saturated Thickness (ft)Estimated from dewatering analyses for Cells 4a and 4b (Geosyntec, 2007a and 2007b).
0.1 Saturated Thickness (m)Estimated from dewatering analyses for Cells 4a and 4b (Geosyntec, 2007a and 2007b).
Note: For tailings Cells 4a and 4b, phreatic surface is assumed to be parallel to the native ground 0.1 m above native ground.
Depth from Top
of Cover (ft)
Depth from Top of
Cover (m)σvo (psf)σvo (kN/m2)σ'vo (psf)σ'vo (kN/m2) CN (N1)60 (N1)60CS rd CSR CRR7.5 FS
12 3.66 1,306 63 1,286 61.6 1.22 3.22 4.71 1.15432 8.4 0.975 0.097 0.099 1.82
15 4.57 1,592 76 1,572 75.3 1.13 3.13 4.71 1.15432 8.3 0.969 0.096 0.099 1.82
18 5.49 1,879 90 1,858 89.0 1.06 3.06 4.71 1.15432 8.2 0.962 0.095 0.098 1.83
21 6.40 2,165 104 2,144 102.7 0.99 2.99 4.71 1.15432 8.2 0.954 0.094 0.097 1.83
24 7.31 2,451 117 2,431 116.4 0.94 2.94 4.71 1.15432 8.1 0.945 0.093 0.097 1.84
27 8.23 2,737 131 2,717 130.1 0.89 2.89 4.71 1.15432 8.0 0.934 0.092 0.096 1.86
30 9.14 3,023 145 3,003 143.8 0.84 2.84 4.71 1.15432 8.0 0.921 0.090 0.096 1.88
33 10.06 3,310 158 3,289 157.5 0.80 2.80 4.71 1.15432 7.9 0.904 0.089 0.095 1.90
36 10.97 3,596 172 3,575 171.2 0.76 2.76 4.71 1.15432 7.9 0.883 0.087 0.095 1.94
39 11.89 3,882 186 3,862 184.9 0.73 2.73 4.71 1.15432 7.9 0.860 0.084 0.095 1.99
42 12.80 4,168 200 4,148 198.6 0.70 2.70 4.71 1.15432 7.8 0.833 0.082 0.094 2.05
45 13.72 4,454 213 4,434 212.3 0.67 2.67 4.71 1.15432 7.8 0.804 0.079 0.094 2.12
48 14.63 4,741 227 4,720 226.0 0.64 2.64 4.71 1.15432 7.8 0.773 0.076 0.094 2.19
51 15.54 5,027 241 5,006 239.7 0.62 2.62 4.71 1.15432 7.7 0.743 0.073 0.094 2.28
References
Bowles, J., 1988. Foundation Analysis and Design, Fourth Edition. McGraw-Hill, Inc. New York.
Chen and Associates, Inc., 1987. Physical Soil Data, White Mesa Project, Blanding Utah, Report prepared for Energy Fuels Nuclear, Inc.
Colorado Schoo of Mines Research Institute (CSM), 1978. Grinding Reports - DSM Screen Undersize. 5 June, 1978.
Denison Mines USA Corporation (Denison), 2009. Reclamation Plan, White Mesa Mill, Blanding Utah, Revision 4.0, Attachment E – Evaluation of Potential Settlement due to Earthquake Induced Liquefaction and Probabilistic Seismic Risk Assessment. November.
Geosyntec Consultants (Geosyntec). 2007a. Analysis of Slimes Drain (Cell 4A). May 11.
Geosyntec Consultants (Geosyntec). 2007b. Analysis of Slimes Drain (Cell 4B). August 30.
MWH, 2011. White Mesa Mill Updated Tailings Cover Design Report. Prepared for Denison Mines (USA) Corp. September 2011.
MWH, 2012. Technical Memorandum: Site-Specific Probabilistic Seismic Hazard Analysis for the White Mesa Uranium Facility. Blanding, Utah. September, 2011.
University of Wisconsin-Madison (UWM), Wisconsin Geotechnics Laboratory, 2012. Compaction and Hydraulic Properties of Soils from Banding, Utah. Geotechnics Report NO. 12-41 by C.H. Benson and X. Wang. July 24.
U.S. Nuclear Regulatory Commission (NRC), 1989. Calculation of Radon Flux Attenuation by Earthen Uranium Mill Tailings Covers, Regulatory Guide 3.64. June.
Western Colorado Testing, Inc., 1999. Report of Soil Sample Testing of Tailings Collected from Cell 2 and Cell 3, Prepared for International Uranium (USA) Corporation. May 4.
Youd, T.L. et al., 2001. Liquefaction Resistance of Soils: Summary report from the 1996 NCEER and 1998 NCEER/NSF Workshops of Evaluation of Liquefaction Resistance of Soils, Journal of Geotechnical and Geoenvironmental Engineering, October.
The dry density of the tailings was estimated as 90 pcf, based on laboratory tests (Chen and Associates, 1987. Western Colorado Testing, 1999) and assuming the long-
term density of the tailings is at 85 percent of the average laboratory measured maximum dry density.
Denison Mines (USA) Corp. (Denison), 2012. Responses to Interrogatories – Round 1 for Reclamation Plan, Revision 5.0, March 12. Attachment H - Supporting Documentation for Interrogatory 12/1: Revised Appendix C, Radon Emanation Modeling, to the Updated
Tailings Cover Design Report (Appendix D of Reclamation Plan, Revision 5.0). August 15

ATTACHMENT G

SUPPORTING DOCUMENTATION FOR INTERROGATORY 07/1:

REVISED APPENDIX D, VEGETATION AND BIOINTRUSION,
TO THE UPDATED TAILINGS COVER DESIGN REPORT
(APPENDIX D OF RECLAMATION PLAN, REVISION 5.0)

VEGEETATION
APP
AND BIO
PENDIX D

OTINTRU
Updated T
D
SION EV
Tailings Cov
VALUATIO
er Design R
ON
Report

Denison M

D.1 IN
This app
evapotra
site. A c
cover an
assist in
the short
ET cove
characte
and root
cover an
biointrus
conducte
D.2 P
The follo
White M
compatib
assumpt
species a
•
•
•
•
•
•
•
•
•
•
•
•
•
These sp
D.3 P
Given a
each sp
permane
ines Corp.
NTRODUCT
endix provid
nspiration (E
critical comp
d will functio
removing w
t-term estab
er are add
ristics of spe
t distribution
d leaf area
ion from bot
ed in June 20
PROPOSED
wing 13 spe
esa Mill site
bility, and l
ion that inst
are:
Western w
Bluebunc
Slender w
Streamba
Pubescen
Indian rice
Sandberg
Sheep fes
Squirrelta
Blue gram
Galleta, v
Common
White sag
pecies are de
PROPOSED
mixture of t
ecies. See
ent cover of
TION
des an evalu
ET) cover p
onent of an
on over the l
ater through
lishment an
dressed.
ecies (i.e., lo
n), characte
index [LAI])
th plants and
012 and liter
SPECIES F
ecies (11 gra
e. These s
long-term s
itutional con
wheatgrass,
ch wheatgras
wheatgrass,
ank wheatgra
nt wheatgras
egrass, varie
g bluegrass,
scue, variety
ail, variety To
ma, variety H
variety Viva (
yarrow, no v
ge, variety S
escribed in m
SEEDING R
the species
eding rates
grasses an
uation of veg
roposed for
ET cover is
ong term to
h the process
d long-term
These issu
ongevity, su
ristics of th
, and soil re
d animals is
rature applic
FOR ET COV
asses and 2
species wer
sustainability
ntrols will ex
variety Arrib
ss, variety G
variety San
ass, variety
ss, variety Lu
ety Paloma
variety Can
y Covar (Fes
oe Jam Cree
Hachita (Bou
(Hilaria jame
variety (Ach
Summit (Arte
more detail l
RATES
listed abov
were deve
nd forbs in
D-1
getation that
reclamation
s the plant co
provide pro
s of transpir
sustainabili
ues include
stainability,
e establishe
equirements
addressed
cable to site
VER RECLA
forbs) are p
re selected
y. Species
clude grazin
ba (Pascopy
Goldar (Pseu
Luis (Elymu
Sodar (Elym
una (Thinop
(Achnatheru
bar (Poa se
stuca ovina)
ek (Elymus e
uteloua graci
esii)
illea millefol
emisia ludovi
later in this a
ve, Table D.
eloped base
a mixture th
Updated T
t would be u
n of tailings
ommunity th
otection from
ration. In thi
ity of vegeta
e: plant sp
compatibility
ed plant co
for sustaine
using inform
conditions.
AMATION
proposed fo
for their ad
s were als
ng by domes
yrum smithii)
udoroegneria
us trachycau
mus lanceola
pyrum interm
um hymenoid
cunda)

elymoides)
ilis)
lium)
iciana).
appendix.
.1 presents
ed on the
hat would p
Tailings Cov
used as an in
cells at the
hat will be es
m wind and w
s appendix,
ation propos
pecies selec
y, competitio
mmunity (i.e
ed plant gro
mation from a
r the ET cov
daptability to
so selected
stic livestock
)
a spicata)
ulus)
atus ssp. psa
medium ssp.
des)
broadcast s
objective o
promote com
er Design R
MWH America
Augus
ntegral part
White Mesa
stablished o
water erosion
issues relat
ed as part o
ction, ecolo
on, rooting d
e., percent
owth. In add
an on-site su
ver system a
o site condit
based on
k. The prop
ammophilus
barbulatum)
seeding rate
of establishi
mpatibility am
Report
as, Inc.
st 2012
of an
a Mill
on the
n and
ted to
of the
ogical
depth
plant
dition,
urvey
at the
tions,
n the
posed
s)
)
es for
ng a
mong

Denison M

species a
rate is b
presente
The num
rate is th
as the nu
the same
some rat
Seeding
seeds pe
unit area
amount,
erroneou
large see
while Ind
calculate
of blue g
be very e
Table D
Sc
Grasses
Pascopy
Pseudor
Elymus t
Elymus l
Elymus e
Thinopyr
Achnath
Poa secu
Festuca
Boutelou
Hilaria ja

Forbs
Achillea
occident
Artemisia

Total
†Seeding ‡Introduce
outside of

Seeding
desired n
ines Corp.
and minimize
based on po
ed below.
mber of seed
he sum of th
umber of se
e species ca
tes are for m
rates are d
er square foo
a (e.g. poun
the develop
us rates that
eded specie
dian ricegra
ed simply on
rama seed
easy to over
.1. Species
cientific Nam
s
yrum smithii
roegneria spic
trachycaulus
lanceolatus
elymoides
rum intermed
erum hymeno
unda
ovina
ua gracilis
amesii
millefolium, v
talis
a ludoviciana
rate is for bro
ed refers to sp
f North Ameri
rate may b
number of p
e competitiv
ounds of pu
s placed in
he individual
eeds per squ
an be found i
monocultures
developed o
ot). Once th
ds per acre
pment of se
t will tend to
s. For exam
ss has app
the basis o
has four tim
plant blue g
s and Seedi
me
We
cata Blu
Sle
Str
Sq
dium Pu
oides Ind
Sa
Sh
Blu
Ga

variety Co
Wh

oadcast seed
pecies that ha
ca. Also refe
e calculated
plants per un
ve exclusion
ure live see
a unit area
species see
uare foot or
in the literatu
s and other r
n the basis
his number is
e). Since ea
eding rates
o over emph
mple, blue g
proximately
f weight per
es the numb
grama and u
ng Rates Pr
Common N

estern wheatg
uebunch whea
ender wheatg
reambank wh
uirreltail
bescent whea
dian ricegrass
ndberg blueg
eep fescue
ue grama
alleta
ommon yarrow
hite sage
and presente
ave been ‘intr
erred to as ‘ex
d from an e
nit area. Fo
D-2
or loss of sp
d per acre
of soil is ca
eding rates.
pounds per
ure. The pri
rates are for
of number
s determined
ach species
based pure
hasize smal
grama has a
175,000 see
r unit area, w
ber of seeds
nder plant In
roposed for
Name
grass
atgrass
rass
eatgrass
atgrass
s
grass
w
ed as pounds
roduced’ from
xotic’ species.
xpected fiel
r purposes o
Updated T
pecies over
(lbs PLS/ac
lled the see
Seeding ra
r acre. Man
mary reason
diverse mix
of seeds pe
d, then it ca
s produces s
ely on weigh
l seeded sp
approximatel
eds per pou
without recog
s per pound
ndian ricegra
r ET Cover
Varietal
Name

Arriba
Goldar
San Luis
Sodar
Toe Jam
Luna
Paloma
Canbar
Covar
Hachita
Viva

No variety
No variety

s of pure live s
m another geo
.
d emergenc
of calculatio
Tailings Cov
time. The p
cre), with fu
eding rate. T
ates are nor
ny different s
n for these d
xtures.
er unit area
n be conver
seed that w
ht per unit a
pecies and u
y 700,000 s
und. If see
gnizing the f
as Indian ri
ass.
at the Whit
Native/
Introduce

Native
Native
Native
Native
Native
Introduced
Native
Native
Introduced
Native
Native

Native
Native

seed per acre
ographic regio
ce for each
on, field eme
er Design R
MWH America
Augus
proposed see
urther discu
The total see
rmally expre
seeding rate
differences is
a (e.g. numb
rted to weigh
weighs a diff
area will pro
under-emph
seeds per po
eding rates
fact that a p
cegrass, it w
e Mesa Mill
ed
Seedin
Rate (lb
PLS/acr

3.0
3.0
2.0
2.0
2.0‡ 1.0
4.0
0.5
‡ 1.0
1.0
2.0

0.5
0.5

23.0
e (lbs PLS/acr
on, typically
species an
ergence for
Report
as, Inc.
st 2012
eding
ssion
eding
essed
es for
s that
ber of
ht per
ferent
oduce
asize
ound,
were
pound
would
l Site
ng
bs
re)†
re).
d the
small

Denison M

seeded g
Field em
Natural R
per squa
precipitat
expected
area to
favorable
facing as
or when
the drill r
A CQAQ
rates are
purchase
certificati
assures
agency r
germinat
origin, g
weight), o
guarante
Once the
date that
greater th
applied u
also calle
usually m
of about
will be di
seeding c
terms of
obtained
comparin
applied i
other ha
distributio
seeding
D.4 E
P
D.4.1 E
Importan
the para
Alderson
adapted
textural r
ines Corp.
grasses and
mergence is
Resource Co
are foot as
tion betwee
d field emerg
control eros
e growing co
spect, good
the seed is b
rate for favor
QC Plan for
e achieved
ed as poun
ion program
the custom
responsible
tion for each
ermination
other crop a
ee that the se
e seed is obt
t the seed w
han 6 month
using a broa
ed an end-g
mounted on
20 feet or m
stributed us
conditions.
pounds pe
. During t
ng pounds o
n two separ
alf of seed w
on across t
rate if the sp
ECOLOGICA
PLANT COM
Ecological C
nt ecological
agraphs that
n and Sharp
to the eleva
ranges (loam
d forbs is as
assumed to
onservation
a minimum
en 6 and 18
gence of 50%
sion and su
onditions, so
moisture, an
broadcast, s
rable conditi
application
is as follow
nds of pure
ms may be a
mer that the
for seed ce
h species of s
percentage,
and weed se
eed being pu
tained, seed
was tested f
hs old, the s
dcasting me
gate seeder
the back of
more. Prior
sing the broa
Seed will th
r acre. Thi
he seeding
of seed app
rate passes
will be spre
the site is h
pecified rate
AL CHARAC
MMUNITY
Characterist
characteris
t follow. S
(1994), Wa
ation (5,600
m to sandy
ssumed to b
o be around
Service reco
number of
8 inches.
% should pro
uppress ann
oils that are
nd adequate
seeding rates
ons.
rates and p
ws. The firs
live seed.
adopted by
seed is co
ertification s
seed. When
date of th
eeds, and ine
urchased me
d labels wou
for percent
eed would b
ethod. This
r. These br
a small trac
to seeding,
adcaster and
en be collec
is process w
process, th
plied to the s
. One-half
ead in a pe
highly unifor
is not being
CTERISTICS
tics of Plant
stics for each
pecies infor
sser (1982)
0 feet), prec
clay) that a
D-3
be around 5
30% if ger
ommends a
seeds whe
Twenty pur
oduce an ad
nual invasio
not extreme
e soil nutrien
s are increa
procedures f
st step begin
Each Sta
seed growe
orrectly iden
sets minimu
n certified, a
he germinat
ert material.
eets minimu
ld be checke
purity and p
be tested ag
procedure w
roadcasters
ctor and gen
a known ar
d simulating
cted and wei
will be repe
he seeding
size of the
of the seed
erpendicular
rm and also
g achieved.
S OF PROPO
t Species o
h species p
rmation was
, and Thorn
ipitation (13
are well with
Updated T
50% if germ
rmination is
seeding rat
n drill seed
re live seed
dequate num
on. This s
e in texture,
nts. When c
sed up to a
for confirmin
ns with a s
ate has a s
ers. Certific
tified and g
m standard
a container o
ion test, pe
The certific
um standards
ed to determ
percent germ
ain before b
would use a
operate wit
nerally have
rea will be c
conditions t
ghed to dete
eated until th
rate will b
area seede
will be spre
direction.
o provide th
OSED SPEC
of Tailings C
roposed for
s obtained f
burg (1982)
3 inches per
hin the env
Tailings Cov
ination is gr
between 60
te of 20 to 30
ing in areas
ds per squa
mber of plan
seeding rate
gentle slop
conditions a
level that is
ng that spe
seed order.
seed certify
ation of a c
genetically p
s for mecha
of seed must
ercentage o
cation is the
s and the qu
mine the perc
mination. If
being accept
centrifugal t
th an electri
an effective
covered with
that would e
ermine actua
he specified
e verified a
ed. In addit
ead in one d
This will e
he opportun
CIES AND E
Cover Syste
r reclamation
from Monse
). The propo
r year on av
ironmental c
er Design R
MWH America
Augus
reater than
0 and 80%.
0 pure live s
s with an an
are foot, wit
ts on the se
e is primaril
pes, north or
are less favo
two to four t
cified applic
Seed wou
ying agency
container of
pure. The
anical purity
t be labeled
of pure seed
consumer’s
uality specifie
cent PLS an
f the test da
ted. Seed w
type broadca
ic motor and
e spreading
a tarp and
exist under a
al seeding ra
d seeding ra
at least onc
ion, seed w
direction an
ensure that
nity to adjus
ESTABLISH
em
n are provid
en et al. (2
osed specie
verage), and
conditions o
Report
as, Inc.
st 2012
80%.
The
seeds
nnual
th an
eeded
ly for
r east
orable
times
cation
ld be
y and
seed
State
y and
as to
d (by
s best
ed.
nd the
ate is
will be
aster,
d are
width
seed
actual
ate in
ate is
ce by
will be
d the
seed
st the
HED
ded in
2004),
es are
d soil
of the

Denison M

White Me
in the fol
Western
rhizomat
annual p
ranges u
mining re
regions b
stands o
regenera
seedlings
reproduc
Bluebun
is a nativ
in texture
found in
tolerant a
14 inch
Bluebunc
to 10,000
Slender
native, c
lived spe
other wh
pioneer
addition,
common
rehabilita
drought t
can grow
ines Corp.
esa Mill site.
lowing parag
n wheatgras
ous, long-liv
precipitation
up to 9,000
elated distu
because of
of both war
ates readily
s and high s
ce by seed e
nch wheatgr
ve, cool seas
e, depth and
sagebrush
and regener
mean annu
ch wheatgra
0 feet.
wheatgras
ool season,
ecies (5 to 10
heatgrasses
species; its
it is able
ly seeded
ate native c
tolerant. It p
w on sites wit
. Table D.2
graphs.
ss, variety A
ved perennia
zone and is
feet. Wes
rbances, for
its ease of e
rm and coo
following bu
seed produc
ensures long
rass, variet
son perennia
d parent ma
communitie
rates vegeta
ual precipita
ass performs
ss, variety
perennial b
0 years) but
in this cha
seedlings
to establish
in mixtures
communities
performs bes
th precipitati
presents a
Arriba (Pasc
al cool seas
s adapted to
stern wheatg
r erosion co
establishme
ol season s
urning. The
ction. The c
-term sustai
ty Goldar (P
al bunch gra
aterial. It is
es in the in
tively follow
ation range
s well in mix
San Luis (
bunch grass
it reseeds a
aracteristic.
are vigorou
h and comp
with other
. It is ada
st at sites w
ion levels as
D-4
summary of
copyrum sm
son grass.
o a wide ra
grass has b
ontrol and fo
nt and abilit
pecies. W
e variety of
combination
nability of th
Pseudoroeg
ass. Bluebu
one of the
ntermountain
ing burning.
and is cons
tures with o
(Elymus tra
s that occas
and spreads
Slender w
s and capa
pete with w
r grasses a
pted to a w
with an annua
s low as 13 i
Updated T
f the ecologi
mithii)—Wes
It grows we
nge of soil
been an imp
or critical ar
ty to grow s
Western whe
Arriba is kn
of its ability
his species.
gneria spica
nch wheatg
most impor
n west. Bl
This speci
sidered to
other species
achycaulus)
sional produ
well by natu
wheatgrass
able of esta
weedy specie
and forbs to
wide variety
al precipitati
nches.
Tailings Cov
cal characte
stern wheatg
ell in a 10 t
textural clas
portant spec
rea stabiliza
uccessfully
eatgrass is
nown for rap
y to spread
ata)—Bluebu
rass grows o
rtant and pro
uebunch w
ies is well ad
be highly d
s and grows
)—Slender
ces rhizome
ural seeding
can serve
ablishing on
es. Slende
o restore d
of sites an
ion of 15 inc
er Design R
MWH America
Augus
eristics discu
grass is a na
to 14 inch m
sses at elev
cies for rest
ation in sem
in pure or m
fire tolerant
pidly establis
vegetatively
unch wheatg
on soils that
oductive gra
heatgrass is
dapted to a
drought resis
s at elevation
wheatgrass
es. It is a s
, exceeding
as an impo
harsh sites
er wheatgra
disturbances
nd is moder
ches or more
Report
as, Inc.
st 2012
ussed
ative,
mean
vation
toring
mi-arid
mixed
t and
shing
y and
grass
t vary
asses
s fire
12 to
stant.
ns up
is a
short-
most
ortant
s. In
ass is
s and
rately
e, but

D

W
B
w
S
S
w
P
w
I
S
S
S
B
G
C
W
a
b
c
d
e
f
g
h
i
j2
Denison Mines Cor
Table D.2. Su
Sp
e
c
i
e
s

Western wheatgr
Bluebunch
wheatgrass
Slender wheatgra
Streambank
wheatgrass
Pubescent
wheatgrass
Indian ricegrass
Sandberg bluegra
Sheep fescue
Squirreltail
Blue grama
Galleta
Common yarrow
White sage
aKey to Ratings—bSoil Texture CodcDepth representsdWyatt et al., 198eWeaver and ClefCoupland and JogFoxx and TiernehSpence, 1937.
USDA, 2012.
2009; Monsen et
rp.
ummary of Eco
Or
i
g
i
n

ass Native
Native
ass Native
Native
Introduced
Native
ass Native
Introduced
Native
Native
Native
Native
Native
—4 = Excellent, 3
des—S = Sand, C
s minimum depth
0.
ments, 1938.
ohnson, 1965.
y, 1987.
al., 2004.
ological Charac
An
n
u
a
l

o
r

P
e
r
e
n
n
i
a
l

Perennial V
Perennial S
Perennial S
Perennial V
d Perennial V
Perennial S
Perennial S
d Perennial S
Perennial S
Perennial V
Perennial V
Perennial V
Perennial V
= Good, 2 = Fair,
C = Clay, L = Loa
h; no information i
cteristics of Pla
Me
t
h
o
d

o
f

S
p
r
e
a
d

Ea
s
e

o
f

Et
b
l
i
h

t
a
Vegetative 4
Seed 4
Seed 4
Vegetative 4
Vegetative 4
Seed 3
Seed 4
Seed 4
Seed 3
Vegetative 2
Vegetative 3
Vegetative 4
Vegetative 4
, 1 = Poor
m
in the literature on
D-5
ant Species Pr
Es
t
a
b
l
i
s
h
m
e
n
t
a
Co
m
p
a
t
i
b
i
l
i
t
y

w
i
t
h

Ot
h
e
r

S
p
e
c
i
e
s
a
Lo
n
g
e
v
i
t
y
a
3 4
4 4
4 2
4 4
2 4
4 4
4 4
2 4
4 3
4 4
4 4
3 4
4 4
n average or max
roposed for the
An
n
u
a
l

P
r
e
c
i
p
i
t
a
t
i
o
n

Ra
n
g
e

(
i
n
c
h
e
s
)

El
e
v
a
t
i
o
n

R
a
n
g
e
10-14 ≤9
12-14 ≤10
13-18 ≤10
11-18 ≤10
12-18 ≤10
6-16 ≤10
12-18 ≤12
10-14 ≤11
8-15 ≤11
10-16 ≤10
6-18 ≤8
13-18 ≤11
12-18 ≥5
ximum depth cou
Updated Tai
e ET Cover at t
El
e
v
a
t
i
o
n
Ra
n
g
e

(f
e
e
t
)

So
i
l

T
e
x
t
u
r
e
b
,000 S,C,L
0,000 S,C,L
0,000 S,C,L
0,000 S,C,L
0,000 S,C,L
0,000 S,L
2,000 S,C,L
1,000 S,C, L
1,000 S,C,L
0,000 S,L
,000 S,C,L
1,000 S,C,L
,000 S,C,L
uld be found.
lings Cover Des
MWH Am
A
the White Mesa
Ro
o
t
i
n
g

D
e
p
t
h

(c
m
)

So
i
l

S
t
a
b
i
l
i
z
a
t
i
o
n
a
a
109d 4
122e 4
109d 2
165f 4
185d 4
84g 2
45h 2
56e 3
30c,i 2
119g 4
30j 4
105h 4
20c,i 3
sign Report
mericas, Inc.
August 2012
a Mill Site
Dr
o
u
g
h
t

T
o
l
e
r
a
n
c
e
a
Fi
r
e

T
o
l
e
r
a
n
c
e
a
4 4
4 4
2 2
4 3
4 3
4 2
3 4
4 2
4 3
4 4
4 4
3 2
3 2

Denison M

Streamb
Streamba
lanceolat
rhizomat
performs
wide rang
mine lan
annual w
Pubesce
Pubesce
highly dr
is adapte
persisten
and has
Indian ri
cool seas
the most
tolerant s
on soils
the mean
persisten
Sandber
season p
damage.
Intermou
establish
are not o
Sheep f
introduce
of 10 to
species t
Turkey a
control.
tolerant.
Squirrelt
perennia
undesira
on all so
tolerant o
Blue gra
warm sea
is mostly
but does
ines Corp.
bank wheat
ank wheatg
tus ssp. lanc
ous and ad
s well in me
ge of soil tex
nd reclamati
weeds. Its hi
ent wheatg
ent wheatgra
ought tolera
ed to a wide
nt species, s
been found
icegrass, va
son, perenn
t common g
species used
ranging from
n annual pre
nt once it bec
rg bluegras
perennial bu
Sandberg
untain area.
hed in areas
overly compe
fescue, var
ed perennial
14 inches.
that greens
and is comm
This variety
tail, variety
l that is se
ble annual g
oil textures in
of fire becau
ama, variet
ason bunchg
y concentrate
s best on w
tgrass, var
grass is co
ceolatus) tax
apted to the
an annual p
xtures, from
on and is b
ghly rhizom
grass, varie
ass is a lon
ant and grow
range of so
should be se
to be effecti
ariety Palom
ial bunchgra
grasses on
d in mine la
m sandy to h
ecipitation is
comes estab
ss, variety C
unchgrass th
bluegrass i
It grows at
with a mea
etitive, and th
riety Cova
l that grows
It is long-liv
up early in
monly used i
y was selec
y Toe Jam
elected for it
grasses. It
n mean ann
se of its sma
y Hachita (
grass. Blue
ed near the
well-drained
riety Soda
onsidered to
xa. Variety
e western in
precipitation
sandy to cla
best known
atous nature
ety Luna
ng-lived sod
ws where the
il textures, f
eeded at low
ve in reduci
ma (Achnat
ass with a h
semi-arid la
nd reclamat
heavy clays.
6 to 16 inch
blished.
Canbar (Po
hat is adapt
is one of the
t elevations
n annual pre
herefore hig
r (Festuca
well on infe
ed and high
the spring.
n mine land
cted becaus
m Creek (E
ts ability to
grows along
nual precipita
all size.
(Bouteloua
e grama prod
soil surface
soils and o
D-6
r (Elymus
o be part o
Sodar is a n
ntermountain
ranges betw
ayey. Strea
for its abilit
e ensures lo
(Thinopyru
forming pe
e mean annu
rom sand to
w densities t
ng the estab
therum hym
ighly fibrous
ands in the
tion. It gene
It grows fr
hes. Indian
a secunda)
ed to all so
e more com
from 1,000
ecipitation o
hly compatib
ovina)—S
ertile soils in
hly drought t
The propos
d reclamation
se plants are
Elymus ely
establish q
g an elevatio
ations zones
gracilis)—
duces an eff
e. Blue gram
once establi
Updated T
lanceolatu
of the thick
native, peren
n area. It is
ween 11 an
ambank whe
ty to contro
ong-term sus
um interme
erennial intr
ual precipita
o clay. Pube
to avoid com
blishment of
menoides)—
s root system
west and
erally occurs
rom 2,000 to
ricegrass is
)—Sandberg
oil textures a
mmon early-s
to 12,000 f
of 12 inches
ble with othe
Sheep fescu
n areas with
tolerant. Sh
sed variety,
n for long-te
e persistent
ymoides)—S
quickly and
on range fro
s of 8 to 15
—Blue grama
ficient, widel
ma is adapt
ished, is hig
Tailings Cov
us ssp. ps
kspike whe
nnial sod gr
s highly drou
nd 18 inches
eatgrass is co
ol erosion an
stainability of
edium ssp.
roduced from
ation is 12 in
escent whea
mpetition wit
woody plan
—Indian riceg
m. Indian ric
is one of th
s on sandy s
o 10,000 fee
s slow to est
g bluegrass
and is highly
season bun
feet and can
or more. E
er native spe
ue is a sh
a mean ann
heep fescue
Covar, was
erm stabiliza
t, winter har
Squirreltail
to effective
om 2,000 to
5 inches. Sq
a is a low-g
ly spreading
ted to a vari
ghly drough
er Design R
MWH America
Augus
sammophilu
atgrass (Ely
rass that is h
ught toleran
s. It grows
ommonly us
nd compete
f this specie
barbulatu
m Eurasia.
nches or mo
atgrass is a h
th native sp
nts.
grass is a na
cegrass is o
he most dro
soils, but is f
et in areas w
tablish, but h
is a native,
y resistant t
chgrasses i
n be succes
stablished p
ecies.
ort, mat-for
nual precipit
is a cool se
s introduced
ation and ero
rdy, and dro
is a short-
ely compete
11,000 fee
quirreltail is
rowing pere
g root system
iety of soil ty
ht tolerant.
Report
as, Inc.
st 2012
us)—
lymus
highly
t and
on a
sed in
e with
es.
um)—
It is
re. It
highly
ecies
ative,
one of
ought
found
where
highly
, cool
o fire
n the
ssfully
plants
rming
tation
eason
from
osion
ought
-lived
e with
t and
fairly
ennial
m that
ypes,
This

Denison M

species i
perennia
Galleta,
season g
of annua
soil fertili
Common
species t
used in m
on a vari
inches.
Achillea
form.
White s
pioneer
compatib
on a wide
with a me
D.4.2 L
All of the
wheatgra
perennia
vegetativ
establish
these spe
cover for
cannot b
species w
documen
White M
Thornbur
The pere
individua
or vegeta
the tailin
adapted
such as d
The use
The esta
sustained
may exis
specific e
diversity
organism
ines Corp.
is commonly
ls.
variety Viv
grass with a
al precipitatio
ty and are d
n yarrow (A
that is rhizom
mine land re
ety of soil te
If seed is n
millefolium
age, variet
rhizomatous
ble with pere
e range of s
ean annual p
Longevity an
e species pro
ass (Elymus
l bunchgras
vely with rhi
h quickly and
ecies are inc
r erosion pr
be relied up
will facilitate
nted to be h
Mesa Mill s
rg, 1982).
ennial grass
al plants that
ative plant p
ngs cells wil
nature of th
drought, fire
of a mixture
ablishment
d plant grow
st over a se
environment
and enhan
ms, and adve
y found with
va (Hilaria
dense, fibro
on with soils
drought and f
Achillea mil
matous and
eclamation,
extures and
not available
would be u
y Summit
s forb spec
ennial grasse
soil textures.
precipitation
nd Sustaina
oposed for r
trachycaulu
ss that is sho
izomes. Sq
d is highly e
cluded in the
rotection and
on to provid
e the establi
highly adapt
ite (Monsen
ses and forb
t are long liv
parts like rhi
ll ensure a
hese specie
, and herbiv
e of species
of a diverse
wth. The us
eeded site a
tal condition
nces natural
erse or chan
cool-seaso
jamesii)—G
ous root sys
ranging from
fire tolerant.
llefolium, v
found growi
establishes
found in a m
e for Achille
sed, which
(Artemisia
ies that est
es. It does b
It is adapte
n above 12 in
ability
eclamation o
us) and squir
ort-lived (5 to
quirreltail is
ffective in co
e proposed s
d to effectiv
de consisten
ishment of t
ted to the e
n et al., 20
bs in the pro
ved (30 years
izomes and
permanent
es to site co
vory, and the
for the ET c
e communit
se of a varie
are properly
ns. In additi
recovery p
nges in clim
D-7
n species an
Galleta is a
tem. Gallet
m coarse to

var. occiden
ng from vall
easily from
mean annua
ea millefolium
has the sam
ludovician
tablishes qu
best on well
ed to sites a
nches.
of the tailing
rreltail (Elym
o 10 years)
also a sho
ompeting wi
seed mixture
vely compete
nt and susta
the remainin
elevation, cl
004; Alders
oposed see
s or more) a
tillers. The
or sustaina
onditions, th
eir ability to e
cover also co
ty has man
ety of speci
y matched w
ion, a mixtu
processes fo
matic conditio
Updated T
nd is highly
a strongly rh
ta grows on
fine. Plants
ntalis)--Yarro
ey bottoms
seed and is
al precipitatio
m var. occid
me growth c
na)--White s
uickly on di
-drained soi
above 5,000
gs cells are l
mus elymoide
but has the
ort-lived pere
ith undesira
e because o
e with annu
ainable plan
ng long-lived
imate, and
son and Sh
ed mixture in
and are able
e use of thes
able plant c
eir toleranc
effectively re
ontributes to
ny advantag
ies ensures
with species
re of specie
ollowing imp
ons. Finally
Tailings Cov
compatible
hizomatous
sits receivin
s have a low
ow is a com
to timberline
s highly per
on range be
dentalis, the
characteristi
sage is con
isturbed site
ils, but can b
feet in eleva
long-lived, e
es). Slende
ability to re
ennial but h
ble annual g
of their ability
ual and bien
nt cover. T
d perennials
soil conditio
harp, 1994;
nclude spec
e to reproduc
se species
cover becau
e to environ
eproduce ove
o longevity a
ges over a
that divers
s that are a
es reverses
pacts from
y, mixtures p
er Design R
MWH America
Augus
with other n
perennial w
ng 6 to 18 in
w requireme
mmon native
e. It is comm
rsistent. It g
tween 13 an
en the introd
ics as the n
nsidered to
es and is h
be found gro
ation and to
except for sle
r wheatgras
seed and sp
has the abil
grasses. Bo
y to provide
nnial species
The use of t
s that have
ons found a
Wasser, 1
cies that dev
ce either by
in reclamati
use of the h
nmental stre
er time.
and sustaina
monocultur
e microsites
adapted to t
the loss of
insects, dis
provide impr
Report
as, Inc.
st 2012
native
warm
nches
nt for
e forb
monly
grows
nd 18
duced
native
be a
highly
owing
sites
ender
s is a
pread
ity to
oth of
quick
s that
these
been
at the
1982;
velop
seed
on of
highly
esses
ability.
re for
s that
those
plant
sease
roved

Denison M

ground c
resource
annual o
where th
D.4.3 C
Reclama
First with
improvem
following
U.S. De
resulted
grassland
of acres
rules and
thousand
proceedi
performa
southeas
a knowle
must be
will fail.
with eac
aggressiv
dominate
many stu
1982; Re
to increa
broadcas
causes s
seeds ar
likely to b
D.4.4 C
There ar
tailings c
attribute.
species i
of specie
species e
invasives
harm) is
subseque
establish
biointrus
seed mix
will effec
et al. (20
that one
because
ines Corp.
cover and s
es such as w
or biennial p
ey are not w
Compatibilit
ation researc
h the resee
ments of lar
more than
epartment o
in the conv
ds through a
of mined lan
d regulations
ds of reclama
ngs, and
ance of indiv
stern Utah (e
edge base a
compatible
The species
h other and
ve [e.g., pu
e the site (M
udies have s
edente et al.
ase compati
st seeded as
species in a
re not placed
be negatively
Competition
re two ways
cells, the use
However,
is undesirab
es that can
establishme
s (i.e., non-
unaccepta
ent reductio
hment of de
ion through
xture will pro
ctively compe
003) present
of the prima
of competit
surface stab
water, nutrie
plants cons
wanted.
y
ch and its ap
eding of mil
ge tracts of
a half a cen
of Agricultur
version of m
an extensive
nds reclaime
s governing
ation publica
government
vidual specie
e.g., Plumm
about specie
as young, d
s proposed
d seeding ra
ubescent w
Monsen et a
shown excel
, 1984; Syd
bility and to
s opposed to
mixture to b
d in as close
y impacted f

s to view co
e of seeded
competition
ble. Therefo
coexist and
nt and exclu
-native spec
ble because
on in spec
eep rooted
the cover a
oduce a gras
ete with und
t a literature
ary reasons
tion from he
ility, along w
ents, sunligh
idered to b
pplication ha
lions of acr
f arid and se
ntury of rang
re Conserva
more than 40
e seeding pr
ed across th
mine land r
ations in the
t publication
es and mixtu
er et al., 196
es compatib
developing p
for the ET c
ates will be
wheatgrass
al., 2004). T
lent interspe
nor and Red
o reduce co
o drill seede
be placed in
e contact wi
from compet
ompetition.
species to
among see
ore, as state
d also fully
uding seede
cies whose
e of the po
cies diversit
woody plan
and into the
ss-forb comm
desirable spe
e review on
that shrub e
erbaceous sp
D-8
with reducin
ht and spac
be undesirab
ave been on
res following
emi-arid ran
eland explo
ation Reser
0 million acr
rogram. Fin
he U.S. with
reclamation.
form of boo
ns. Many
ures of spec
68; Monsen
ility. Specie
plants or cer
cover at the
used to pre
(Thinopyrum
These speci
ecies compa
dente, 2000
ompetition a
ed. Accordin
potentially c
ith each othe
tition.
In the cont
compete wit
eded specie
ed earlier, th
utilize plant
ed species.
introduction
otential loss
ty, plant co
nts is unac
tailings ma
munity of hig
ecies, includ
shrub estab
establishmen
pecies. This
Updated T
ng weed inv
ce. Weeds
ble or troub
ngoing in the
g the dust
ngelands bet
itation throu
rve Program
res of marg
nally, there h
the implem
Over this t
oks, scientific
y publicatio
cies under se
et al., 2004
es that are
rtain individu
e White Mes
event overse
m intermedi
ies are com
atibility (e.g.,
; Newman a
among seed
ng to Monse
competitive s
er as with d
text of estab
th weeds or
s with the p
he proposed
resources
The establi
n causes ec
of seeded
over, and o
cceptable be
aterial. Onc
ghly adapted
ding shrubs
blishment on
nt is difficult
s finding is
Tailings Cov
vasion by fu
in this con
blesome, es
e U.S. since
bowl of the
tween the 1
ugh overgraz
m was imp
inal farm la
have been te
mentation of f
time period,
c journal arti
ns have r
emi-arid con
4). All of this
seeded toge
uals will suc
a Mill site a
eeding spec
ium)] and c
mmonly seed
, DePuit et a
and Redente
ded species
en et al. (20
situations, w
drilling and th
blishing an
r woody plan
potential loss
seed mixtu
to minimize
shment of w
conomic an
perennial
overall sust
ecause of
ce establishe
d and produc
native to the
n mined lan
in mined lan
also suppor
er Design R
MWH America
Augus
ully utilizing
text are typ
specially gro
the early 19
e 1930s. T
960s and 1
zing. In 198
plemented w
nd to perma
ens of thous
federal and
there have
icles, sympo
reported on
nditions simi
s work has l
ether in mix
cceed and o
are all compa
cies that ma
could poten
ded together
al., 1978; De
e, 2001). Fi
, sites wou
004), drill see
while broadca
herefore are
ET cover o
nts is a desi
s of any of t
ures is comp
e weed or w
weeds, espe
nd environm
species and
tainability.
the potentia
ed, the prop
ctive species
e area. Pas
ds and conc
nd reclamat
rted by DeP
Report
as, Inc.
st 2012
plant
pically
owing
900s.
Then,
1980s
85 the
which
anent
sands
state
been
osium
n the
ilar to
led to
xtures
others
atible
ay be
ntially
r and
ePuit,
nally,
ld be
eding
asted
e less
n the
irable
these
prised
woody
ecially
mental
d the
The
al for
posed
s that
schke
clude
ion is
Puit et

Denison M

al. (1980
adapted
woody sp
compacte
discussio
plant com
D.4.5 P
Monitorin
showed t
5.5% dur
al., 2008
eight spe
proposed
performin
species
species t
were not
similarity
estimate
percent p
vegetativ
Monticell
compare
temperat
precipitat
7,000 fee
In June 2
composit
and Rev
vicinity o
Juniper w
woodland
(Juniperu
the comm
these tw
different
removal
lack of an
The Big
intersper
pallidum
mostly g
jamesii),
cheatgra
coccinea
ines Corp.
0), DePuit (1
and compe
pecies, such
ed radon a
on of big sag
mmunity suc
Plant Cover
ng of an alte
that the plan
ring the first
8). A total o
ecies contrib
d for the W
ng species,
used at Mo
that can be
t considered
y in environ
of 40% was
plant cover
ve cover at
lo because t
d to 15 in
tures are 64
tion and low
et compared
2012 the are
tion and cov
egetation P
f the White
woodland. T
d as a Piny
us osteospe
munity may
o principal p
stages of su
(chaining an
ny understor
Sagebrush
rsed shrubs
var. pallidu
rasses with
squirreltail
ss (Bromus
a), lesser rus
988), Munsh
titive nature
h as big sage
attenuation
gebrush inva
ccession.
ernative cov
nt cover perf
t growing se
of 18 specie
buted 70% o
White Mesa
four of the
onticello tha
highly comp
d acceptable
nmental con
s determine
of 30% was
White Mesa
the average
nches at M
4/37oF for W
wer tempera
d to 5,600 fee
ea surround
ver in respon
lan of DRC
Mesa Mill si
The Dames
yon-Juniper
erma) and th
be more a
plant comm
uccessional
nd plowing)
ry species in
h shrubland
of broom s
um), and ru
an infreque
(Elymus e
s tectorum)
shy milkvetch
hower (1994
e of the spec
ebrush will b
layer from
asion and ro
ver at the M
formed well
eason to nea
s were seed
of the total p
Mill site w
ese species
at are not p
petitive (i.e. s
e for the Wh
nditions betw
d to be a re
s assigned
a is expecte
e annual pre
Monticello a
White Mesa
atures at Mo
et at White M
ing the Whit
nse to Interro
(2012). Th
te. These p
and Moore
community
he presence
appropriately
unity types,
developme
and seedin
n some area
is domina
snakeweed
ubber rabbit
ent occurren
lymoides),
. Forb sp
h (Astragalu
D-9
4), and Mons
cies that wil
be slow and
their roots
ooting depth
onticello, Ut
over a seve
arly 46% in
ded at the M
plant cover.
were seeded
are in the
proposed for
smooth brom
hite Mesa M
ween Monti
easonable es
as a reduce
ed to be slig
cipitation at
and the av
and 59/33
onticello are
Mesa.
te Mesa Mil
ogatory 11/1
here are two
plant commu
Environmen
type, but th
e of pinyon p
y classified
there are a
nt and reflec
g and inten
s.
ated by big
(Gutierrezia
tbrush (Eric
nce of forbs
Indian riceg
pecies inclu
us convallariu
Updated T
sen et al. (2
l be seeded
intrusion int
is not ant
h is presente
tah, Uranium
en year perio
the seventh
Monticello S
Approxima
d at Montic
White Mesa
r White Me
me, crested
ill site. Bas
icello and W
stimate for a
ed performa
ghtly less th
White Mesa
verage annoF for Mont
e due to its
l site was s
: Vegetation
o principal p
unities are B
ntal Report
he primary t
pine (Pinus
as a Junipe
a number of
ct past distu
se grazing a
sagebrush
a sarothroae
cameria nau
s. The gra
grass (Achn
ude scarlet
us), and Rus
Tailings Cov
2004). Beca
d, the invasi
to the cover
ticipated to
ed later unde
m Mill Tailin
od. Plant co
h growing se
Site and of th
ately one ha
ello and of
a mixture.
sa include
wheatgrass
sed on these
White Mesa
a long-term
ance scenar
han what wo
a is approxim
nual maximu
ticello. The
s slightly hig
urveyed for
n and Biointr
plant commu
Big Sagebrus
(1978) class
tree species
edulis) is s
er woodland
f disturbed a
urbances su
as evidence
h (Artemisia
e) pale dese
useosa). Th
sses include
natherum hy
globemallo
ssian thistle
er Design R
MWH America
Augus
ause of the h
on of indige
r below the h
occur. Fu
er the sectio
ngs Disposa
over ranged
eason (Wau
hese 18 spe
alf of the sp
f the eight
High perfor
three introd
, and alfalfa
e results an
a, a plant c
average, wh
rio. The pe
ould be fou
mately 13 in
um/minimum
e slightly gr
gher elevatio
plant comm
rusion Evalu
unity types i
sh shrubland
sified the Ju
s is Utah ju
so infrequen
d. In additio
areas that a
ch as sageb
ed by a com
tridentata)
ert-thorn (Ly
he understo
e galleta (H
ymenoides),
ow (Sphaer
(Salsola kal
Report
as, Inc.
st 2012
highly
enous
highly
urther
on on
l Site
from
gh et
ecies,
ecies
best-
rming
duced
) and
d the
cover
hile a
ercent
nd at
nches
m air
reater
on of
munity
uation
n the
d and
uniper
uniper
t that
on to
are in
brush
mplete
with
ycium
ory is
Hilaria
and
ralcea
li).

Denison M

The Juni
site. It is
sandy lo
Sagebrus
Sagebrus
probabilit
system.
both plan
D.4.6 2
The big s
west of t
transects
D.1). Alo
pin at 1 m
that inter
north, so
vegetatio
Results f
Mill site s
areas no
23.1% co
average
somewha
(1978).
commun
grasses.
1977 wa
addition,
to a long
sampled
maintaine

ines Corp.
per woodlan
s highly unlik
am soil that
sh shrubland
sh commun
ty that this c
A reconnai
nt and anima
012 Plant S
sagebrush c
he restricted
s and estima
ong each 10
meter interv
rsected the
outh and we
on survey co
from the 201
showed a m
orth, south an
over for shr
percent litte
at greater th
In the Env
ity was 33.3
Litter was
s 23.6 cm c
monthly pre
g-term avera
are curren
ed on the ta
nd occurs on
kely that this
t occurs on
d. The vege
nity and did
community t
issance leve
al species th
Survey
community ty
d area of the
ating cover b
00 m long tra
als and reco
point. A to
est of the m
onducted in t
12 sampling
mean live pla
nd west of th
rubs, 13.7%
er was 13.1%
han the cove
vironmental
3%. This c
estimated a
compared to
ecipitation du
age of 12.5
tly grazed,
ilings cell co

n shallow so
community
the Mill site
etation samp
d not includ
type would
el survey wa
hat occupy th
ype within th
e mill and ta
by species u
ansect, live p
ording the p
otal of 10 tra
mill and taili
the areas su
g of the Big
ant cover of
he mill site (
cover for g
% and bareg
er values re
Report, the
cover include
at 16.9% an
a long-term
uring the pe
cm for the
it is highly
over system
D-10
oils along the
type would
e, which is t
pling that wa
de the Junip
ever establi
as conducte
hese areas.
he White Me
ilings facilitie
using a poin
plant cover b
lant species
ansects wer
ngs cells.
urrounding th
Sagebrush
37.8% after
Table D.3).
grasses, and
ground avera
eported in D
e average l
ed an avera
nd baregrou
m average of
eriod May-Se
same perio
likely that
for condition
Updated T
e canyon rim
expand its r
the primary
as conducted
per woodlan
ish on the M
ed in the Ju
esa Control A
es was surv
t intercept s
by species w
s or ground c
re sampled
Table D.3
he mill and ta
community
r averaging
This plant c
d 1.0% cove
aged 49.1%
ames and M
live plant c
age of 19.4%
und was 49.
f 29.7 cm (D
eptember 19
od. Conside
a cover of
ns that exclu
Tailings Cov
m to the eas
range into th
soil type su
d in 2012 fo
nd because
Mill site or ta
niper comm
Area to the
veyed using
sampling me
was determin
cover (litter
in each of
presents a
ailings cells.
surrounding
live plant co
cover includ
er for forbs.
. These cov
Moore Envir
cover in the
% for shrub
9%. Annua
Dames and
978 totaled 3
ering the fac
40% can b
ude grazing
er Design R
MWH America
Augus
st and west o
he deep, very
upporting the
cused on th
e of the un
ailings cell c
munity to obs
north, south
randomly p
ethod (see F
ned by lower
and baregro
the areas t
summary o
.
g the White M
over estimat
ed an avera
In addition
ver estimate
ronmental R
e Big Sageb
bs and 13.8%
al precipitati
Moore 1978
3.8 cm comp
ct that the a
be achieved
by livestock
Report
as, Inc.
st 2012
of the
y fine
e Big
e Big
nlikely
cover
serve
h, and
laced
Figure
ring a
ound)
o the
of the
Mesa
ted in
age of
n, the
es are
Report
brush
% for
on in
8). In
pared
areas
d and
.

Denison M

Tab
Site and
North of M
o B
o B
o R
o P
o G
o S
o In
o C
o S
o Le
o R
Total Live
Total Litte
Total Bare

South of M
o B
o B
o G
o S
o In
o C
o S
o R
Total Live
Total Litte
Total Bare

West of M
o B
o B
o P
o G
o S
o In
o C
o S
o R
Total Live
Total Litte
Total Bare

The form
issue for
rock frag
matrix of
ines Corp.
ble D.3. Ave
Plant Specie
Mill
ig sagebrush
room snakew
Rubber rabbitb
alm desert-th
Galleta (Hilaria
quirreltail (Ely
ndian ricegras
Cheatgrass (B
carlet globem
esser rushy m
Russian thistle
e Cover
er Cover
eground
Mill
ig sagebrush
room snakew
Galleta (Hilaria
quirreltail (Ely
ndian ricegras
Cheatgrass (B
carlet globem
Russian thistle
e Cover
er Cover
eground
Mill
ig sagebrush
room snakew
ale desert-tho
Galleta (Hilaria
quirreltail (Ely
ndian ricegras
Cheatgrass (B
carlet globem
Russian thistle
e Cover
er Cover
eground
mation of des
discussion.
ments, usua
f finer mater
erage Plant
Surr
es
(Artemisia tr
weed (Gutierre
brush (Ericam
horn (Lycium p
a jaamesii)
ymus elymoid
ss (Achnather
Bromus tectoru
mallow (Sphae
milkvetch (Ast
e (Salsola kali
(Artemisia tr
weed (Gutierre
a jaamesii)
ymus elymoid
ss (Achnather
Bromus tectoru
mallow (Sphae
e (Salsola kali
(Artemisia tr
weed (Gutierre
orn (Lycium p
a jaamesii)
ymus elymoid
ss (Achnather
Bromus tectoru
mallow (Sphae
e (Salsola kali
sert paveme
Desert pav
ally one or tw
rial (Cooke a
t and Groun
rounding th
ridentata)
ezia sarothroa
meria nauseos
pallidum var.
des)
rum hymenoid
um)
eralcea coccin
tragalus conv
i)
ridentata)
ezia sarothroa
des)
rum hymenoid
um)
eralcea coccin
i)
ridentata)
ezia sarothroa
pallidum var. p
des)
rum hymenoid
um)
eralcea coccin
i)
ent and pote
vements are
wo stones th
and Warren
D-11
nd Cover fro
he White Me
ae)
sa).
pallidum)
des)
nea)
vallarius)
ae)
des)
nea)
ae)
pallidum)
des)
nea)
ential impac
e armored su
hick (approxi
, 1973). Th
Updated T
om June 20
esa Mill Site
ct on plant c
urfaces com
mately 2 to
hese surface
Tailings Cov
012 Samplin
e
% Cov

19.1
3.9
0.2
0.1
3.6
0.1
0.1
9.5
0.1
0.1
0.6
37.4
9.7
53.1

18.3
3.0
8.5
0.3
0.1
6.7
0.1
1.4
38.4
13.4
48.2

20.5
4.4
0.1
6.6
0.1
0.1
5.3
0.1
0.8
37.9
16.1
46.0
cover has be
posed of an
3 centimete
es form on a
er Design R
MWH America
Augus
ng in Areas
ver

een raised a
ngular or rou
rs), set on o
arid soils thr
Report
as, Inc.
st 2012
as an
unded
or in a
rough

Denison M

deflation
vegetatio
and do n
1991), as
of desert
(which w
amended
pavemen
D.4.7 L
Monthly
Mesa Mi
including
presents
semi-arid
the ET co
This com
from ear
during th
and use
Jan F
0

D.5 B
D.5.1 P
The pote
system, a
plant spe
rooting d
that exte
proposed
literature
The spec
depth of
depth of
biointrus
a depth o
Proctor d
with root
attenuati
ines Corp.
of fine ma
on (Cooke a
not occur wh
s would be t
t pavement
was confirme
d with grav
nt formation
Leaf Area Ind
leaf area in
ll site. Thre
g: Groenev
a compilati
d herbaceou
over include
mbination of
rly spring to
he cooler tim
more water
Table D
Feb Mar
0 0.3
BIOINTRUSI
Plant Intrusi
ential for lon
assuming no
ecies that a
depths that a
end to a dep
d for estab
e.
cies with the
185 cm. It
f 122 cm,
ion layer. R
of 122 cm w
density). In
ting depth, f
on layer of t
aterial by w
nd Warren,
here either w
he case for
formation e
ed during th
vel, there is
or an assoc
dex
ndex (LAI) v
e primary pu
veld (1997),
on of LAI va
us plant com
e both cool- a
species wil
late fall. C
mes of the gr
during the w
.4. Leaf Are
Apr M
0.7 0
ON
on
g-term plan
o long-term
are proposed
are far less
pth of a min
blishment al
e deepest ro
t is highly u
which is th
Root growth i
will be restric
addition, bo
further decre
he cover sys
ind or wate
1973). Des
wind or wate
the White M
ither on the
he 2012 pla
s no suppo
ciated decrea
alues were
ublications w
Scurlock e
alues based
mmunities. I
and warm-se
l maximize
Cool-season
rowing seaso
warmest peri
ea Index for
Mo
May June
0.6 0.6
t intrusion th
maintenanc
d for establi
than the de
imum of 10
ong with th
oting system
nlikely that
he combined
into the high
cted because
oth root den
easing the p
stem.
D-12
er erosion d
sert pavemen
er erosion a
Mesa cover s
White Mes
ant survey).
orting eviden
ase in plant
estimated f
were used to
et al. (2001)
on North A
t is importan
eason specie
the length o
species are
on, while wa
iod of the ye
r the ET Cov
onth
July Au
1.8 2.
hat could im
ce following
ishment on
pth of the b
.1 feet (308
heir maximu
m is pubesce
this species
d depth of
hly compacte
e of the high
nsity and the
potential for
Updated T
due to a la
nts are not c
are controlled
system. In a
a Mill site o
Even with
nce to indi
cover over t
for the propo
o estimate m
), and Fang
American dat
nt to note th
es.
of the growi
e more prod
arm-season
ear.
ver at White
ug Sept
.4 2.6
mpact the pe
decommissi
the cover s
biointrusion a
8 cm). Tabl
um rooting
ent wheatgra
s or any oth
the erosio
ed radon att
h density of
e size of roo
r root growt
Tailings Cov
ck of prote
common in s
d by plant c
addition, ther
or areas sur
h the use o
cate a pote
the long term
osed ET co
monthly LAI
g et al. (20
ta sets that
hat the prop
ng season
ductive and
species are
e Mesa Mill
Oct No
0.8 0.1
erformance o
ioning is ext
system are
and radon a
e D.5 lists t
depths ob
ass, with a m
her species
on protection
tenuation lay
this materia
ots decreas
h into the c
er Design R
MWH America
Augus
ction by su
semi-arid reg
cover (Hend
re is no evid
rounding the
of a topsoil
ential for d
m.
over at the W
for the ET c
008). Table
were focuse
posed specie
and transpir
use more w
more produ
Site
ov Dec
1 0
of the final c
tremely low.
characterize
attenuation la
the plant sp
btained from
maximum ro
will root bel
n layer and
yer that beg
al (95% Stan
se at a rapid
compacted r
Report
as, Inc.
st 2012
urface
gions
ricks,
dence
e site
layer
desert
White
cover,
e D.4
ed on
es for
ration
water
uctive
cover
The
ed by
ayers
ecies
m the
ooting
low a
d the
ins at
ndard
d rate
radon

Denison M

Table D
Scientif
Pascopy
Pseudor
Elymus t
Elymus l
Elymus e
Thinopyr
Achnath
Poa secu
Festuca
Boutelou
Hilaria ja
Achillea
Artemisia
aWyatt et
1987; eSp
Table D-
establish
root mas
these two
of the all
big sage
time. Ba
big sage
before th
no longe
plant com
because
Tab
Species
Western w
Blue gram

Species
Big sageb
aWeaver 1
In additio
documen
used to
cover sys
and Laue
an estima
ines Corp.
.5. Rooting
ic Name
yrum smithii
roegneria spic
trachycaulus
lanceolatus
elymoides
rum intermed
erum hymeno
unda
ovina
ua gracilis
amesii
millefolium
a ludoviciana
al., 1980; bW
pence, 1937; f
-6 illustrates
hment on the
ss in the 90 t
o species is
species pro
brush, which
ased on the
brush will be
he effects of
er adapted.
mmunity on
it is not exp
ble D.6. Pe
Es
wheatgrassa
maa
0-2
cm
brushb 35
1954; bMcLen
on to the inf
ntation of ro
estimate roo
stem, includ
enroth (1994
ate of effect
g Depths for
cata
dium
oides

Weaver and ClfUSDA, 2012
the reductio
e cover syst
to 120 cm d
s typical of g
oposed for e
h is the mos
climate chan
e sustainabl
f climate cha
Regardless
the tailings
pected to roo
rcent of Ro
stablishmen
0-30 cm
65
94
20
m
20-40
cm
5 19
ndon 2010.
formation pr
ooting depth
ot biomass
ding: Hopkin
4), Jackson e
ive root den
r Species P
ements, 1938
; gMonsen et
on in root m
tem. Both w
depth and no
grasses foun
establishmen
st likely shru
nge scenario
le on site, b
ange alter th
s of the leng
cover syste
ot below 180
ot Mass by
nt of the Co
m 30-60 c
14
4
40-60
cm
60
c
17
esented on
hs and root
by depth fo
ns (1953), B
et al. (1996)
sities by dep
D-13
roposed fo
Common Na
Western whe
Bluebunch w
Slender whe
Streambank
Squirreltail
Pubescent w
Indian ricegr
Sandberg bl
Sheep fescu
Blue grama
Galleta
Common ya
White sage
8; cCoupland
al. 2004.
mass with de
western whe
o root mass
nd in semi-a
nt. Table D
b species to
os presente
ut it is likely
he environm
gth of time th
em, this spe
cm.
Depth for T
over System
cm 60-90
12
1
0-80
cm
80-10
cm
10 7
root archite
biomass by
or the plant
artos and S
), and Gill et
pth for the pr
Updated T
r Establish
ame
eatgrass
wheatgrass
eatgrass
wheatgrass
wheatgrass
rass
uegrass
ue
rrow
and Johnson
epth for two
eatgrass and
below 120
rid environm
.6 also inclu
o colonize th
d later in thi
y to establish
ment to a con
hat big sage
ecies does n
Two of the P
m and Big S
0 cm 90-1
2

0 100-120
cm
5
ecture above
y depth. Si
community
ims (1974),
t al. (1999).
roposed cov
Tailings Cov
ment on the
Roo
n, 1965;dFoxx
of the spec
d blue gram
cm. The ro
ments and a
udes the roo
he tailings co
is appendix,
h through na
ndition that
ebrush rema
not pose a b
Proposed S
agebrush
20 cm 12
9
1
120-140
cm
4
e, Table D.7
ix primary p
that would
Sims and S
The followin
ver system.
er Design R
MWH America
Augus
e Cover Sys
oting Depth(
109a
122b
109a
165c
30d
185a
84e
45f
56b
119e
30g
105f
20d
and Tierney,
cies propose
a have very
ot architectu
re represent
ot architectu
over system
it is unlikely
atural succe
big sagebru
ains a part o
biointrusion
Species for
0-150 cm
0
0
140-160
cm
1
2
7 provides fu
publications
establish o
Singh (1978)
ng table pres

Report
as, Inc.
st 2012
stem
(cm)
,
ed for
y little
ure of
tative
re for
m over
y that
ssion
ush is
of the
issue
160-180
cm
1
urther
were
n the
), Lee
sents

Denison M

Table D.
Depth
0-
15-
30-
45-
60-
75-
90-1
†Maximum
D.5.2 A
The Dam
surround
possible
burrowin
(Microdip
latrans),
longtail w
burrowin
(Peromys
(Thomom
species i
D.5.3 2
In June 2
in respon
and Juni
animals
Transect
spacing
upon phy
species t
during th
northern
animal p
characte
During th
were obs
northern
indication
There we
Report (D
Table D.
may occ
species t
ines Corp.
7. Root Bio
h (cm)
-15
-30
-45
-60
-75
-90
07
m rooting dep
Animal Intru
mes and M
ding the Wh
presence of
g owl (Bu
podops sp.),
red fox (Vu
weasel (Mus
g animals
scus truei) a
mys talpoide
s made in th
012 Burrow
2012 the are
nse to Interr
per commun
or future c
ts were arra
between tra
ysiographic
that would p
he performan
pocket gop
presence in
ristics.
he animal su
served to th
pocket gop
n that a pop
ere no evide
Dames and
8 presents a
ur on the W
that have th
omass for S
Root Biom
Anticipate
0
0
0
0
0
th under the r
sion
Moore Envir
ite Mesa M
f a number o
ubo virginia
vole (Micro
ulpes vulpes
stela frenata
reported to
and deer m
es) was not
he 1978 repo
wing Animal
ea surroundi
rogatory 11/1
nities surrou
colonization
nged in a s
ansects and
features on
potentially re
nce period.
pher. Obse
the form of
urvey one ba
he north of t
her in the sa
pulation of n
ence of poc
Moore, 1978
an updated
White Mesa M
he potential
Species Exp
ass (grams c
ed Performan
0.11
0.17
0.035
0.023
0.021
0.019
0.011
reduced perfo
ronmental R
Mill site. Th
of burrowing
nus), pocke
otus sp.), de
s), striped s
a), and Gun
o occur in
ouse (Perom
t observed
ort.
l Survey
ng the White
1. A total of
nding the m
based on
ystematic m
transect len
the landsca
epresent the
These spec
rvations we
f tracks, sca
adger sightin
the mill com
agebrush co
northern poc
cket gophers
8) and no ev
assessment
Mill site. Ba
for the deep
D-14
pected to O
cm-3)
nce
Ro
ormance scen
Report (197
e Environm
g species in t
et mouse
esert cottonta
skunk (Meph
nison prairie
the Junipe
myscus man
in either co
e Mesa Mill
100 km of t
ill site to det
existing ha
manner (at e
ngths runnin
ape. The pr
e deepest p
cies included
re made alo
at or active
ng was made
mplex. There
ommunities
cket gopher
s during surv
vidence of po
t of maximum
ased on a re
pest burrows
Updated T
ccur on the
oot Biomass
Reduced Pe
0.04
0.12
0.02
0.015
0.014
0.0
0.0
nario would b
78) included
ental Repor
the Big Sag
(Perognath
ail (Sylvilagu
hitis mephiti
e dog (Cyno
er communi
niculatus).
ommunity ty
site was sur
transects we
termine eithe
abitat chara
each location
ng between
rimary focus
otential for
d the badge
ong each tr
burrows, b
e and multip
e appears t
surrounding
rs occurs in
veys associ
ocket gophe
m burrow de
eview of liter
s are badge
Tailings Cov
e Cover Sys
(grams cm-3
rformance
4
2
2
5
4†
0
0
be 68 cm.
d animal s
rt recorded
ebrush com
hus sp.), k
us auduboni
tis), badger
omys gunnis
ity included
The norther
ype and no
rveyed for b
ere walked i
er the prese
acteristics (s
n in Figure D
100 and 40
s of the surv
burrows on
er, Gunnison
ransect for a
urrow densi
ple active pra
to be suitab
g the mill site
n the vicinity
ated with th
ers 34 years
epths for an
rature for bu
er (228 cm),
er Design R
MWH America
Augus
stem
3)
urveys for
the presenc
mmunity, inclu
kangaroo m
ii), coyote (C
(Taxidea ta
soni). Addit
d pinyon m
rn pocket go
o mention o
urrowing an
n Big Sageb
ence of burro
see Figure
D-2) with a
00 m, depen
vey was on
the tailings
n prairie dog
animal sight
ities, and ha
airie dog colo
le habitat fo
e, but there
y of the mill
he Environm
later.
imal species
urrow depths
, northern po
Report
as, Inc.
st 2012
sites
ce or
uding
mouse
Canis
axus),
tional
mouse
opher
of the
imals
brush
owing
D.2).
50 m
nding
three
cells
g, and
tings,
abitat
onies
or the
is no
site.
mental
s that
s, the
ocket

Denison M

gopher (
dog were
pocket g
attempt w
confirm a
hectares
burrow d
dog colo
estimated
ranges fr
ines Corp.
182 cm), an
e observed d
opher occur
was made t
a badger bu
. However,
density is mo
onies that w
d at 148 bu
rom 0 to 148
a. The pro
consists
erosion
attenua
layer ov
system
intrusion
minimiz
combina
expecte
thicknes
attenua
the com
cover.
thicknes
extend
Burrowi
of 122
Standar
compac
burrows
Howeve
because
of the
vegetat
prairie d
will not
badger
prairie d
present
badger
and Gr
species
the maj
found in
tailings
colonize
habitat.
nd Gunnison
during the 2
rs in the vic
to estimate
urrow. The
within the e
ore on the o
were located
rrows per h
8 burrows pe
oposed cov
s of the foll
protection
tion layer ov
ver 76 cm o
does not c
n by burrow
ze burrowing
ation with a
ed burrowin
ss of the co
tion layer lo
mpacted zon
Considering
ss and phys
below 122
ng into the h
cm will be
rd Proctor d
cted zone, th
s being dev
er, this is no
e of the follo
Mill site, p
ion that is s
dogs coloniz
match thei
will be grea
dogs are no
will be low
diet consist
rossenheider
s occurring in
jority of the
n the Junipe
cells domin
e the cells d

n prairie dog
012 animal
inity of the m
burrow dens
highest den
entire bound
order of one
in the area
ectare. Ove
er hectare.
er system i
lowing layer
layer over 1
ver up to 110
of a grading
contain a b
wing anima
g animal intru
a highly com
g depths a
over (total o
ocated at a d
ne will all co
g the anima
sical nature
cm or into t
highly comp
restricted b
ensity). If a
he maximum
veloped in t
ot expected
owing: 1) a
prairie dog
short in verti
zing the tailin
r habitat req
atly influenc
ot present o
because of
ts primarily o
r 1980). A
n the vicinity
diet of bad
er community
nated by her
uring the pe
D-15
g (122 cm).
survey, whil
mill site from
sities for ba
sity was est
dary of the
burrow per
a of the Mil
er the entire
is a monolit
rs from top
107 cm of a
0 to 136 cm
and radon
biobarrier (e
ls. The p
usion throug
mpacted laye
among spec
of 308 cm),
depth below
ontribute to
l species th
of the cover
the very top
acted radon
because of
animals are a
m burrow dep
the upper p
to occur du
although prai
habitat is c
ical stature
ngs cells is v
quirements;
ced by the p
n the tailing
the importan
of prairie do
Among thes
y of the Mill
dgers that in
y, but it is h
rbaceous sp
erformance p
Updated T
Both the b
le there is n
m both the 1
dgers but it
timated to b
Mill site, it
250 to 300
ll site, the g
e Mill site th
thic evapotr
to bottom:
a water stor
of a highly c
attenuation
.g. cobble
roposed co
gh the use o
er placed a
cies that m
the use of
w 122 cm, an
minimizing
at may inha
r, it is not an
p portion of
n attenuation
the high de
able to burro
pth of 308 c
portion of t
uring a perfo
irie dog colo
characterize
(Holechek e
very low bec
and 2) the
presence or
gs cells, the
nce of prairi
ogs, ground
e species,
site and the
nhabit this
ighly unlikel
pecies or ev
period becau
Tailings Cov
badger and
no evidence
1978 and 20
t was not alw
be one burro
was estima
hectares. W
greatest bur
e prairie do
ranspiration
15 cm of
rage, biointr
compacted r
layer. The
layer) to m
over system
of thick layer
at a depth t
may inhabit
f a highly c
nd a final 76
any biointru
abit the tailin
nticipated th
the highly c
n layer that b
ensity of thi
ow into or th
cm (Table D.
he radon a
ormance per
onies are fou
ed by low
et al. 1998);
cause plant c
use of the
r absence o
e probability
ie dog in the
squirrels, an
the prairie
erefore assu
area. Grou
y that they w
ven big sage
use of the la
er Design R
MWH America
Augus
Gunnison p
that the nor
012 surveys
ways possib
ow per 80 to
ated that ba
Within the p
rrow density
g burrow de
(ET) cover
f a topsoil-g
rusion and r
radon attenu
e proposed c
minimize pote
m is designe
rs of soil cov
hat is below
the site.
compacted r
6 cm layer b
usion throug
ngs cells an
hat burrowin
compacted z
begins at a d
is material
hrough the h
.8) could res
attenuation l
riod of 200 y
und in the vi
plant cover
the potenti
cover and st
tailings cel
of prairie do
of badger b
e badger die
nd gophers
dog is the
umed to mak
und squirrels
would inhab
ebrush that c
ack of approp
Report
as, Inc.
st 2012
prairie
rthern
s. An
ble to
o 100
adger
prairie
y was
ensity
r that
gravel
radon
uation
cover
ential
ed to
ver in
w the
The
radon
below
h the
d the
g will
zone.
depth
(95%
highly
sult in
layer.
years
cinity
r and
al for
tature
lls by
ogs; if
being
et; the
(Burt
only
ke up
s are
bit the
could
priate

Denison M

Table
M
S
Pocket mo
Pinyon mo
Deer mou
Kangaroo
Vole
Desert co
Long-taile
Striped Sk
Badger
Gunnison
Red fox
Coyote
Burrowing
Northern

D.6 S
There ar
The first
site. The
over the
volume.
There ar
sustainab
(EC), so
macronu
D.9 prese
sustained
potential
ines Corp.
b. Howeve
season
opportu
stature
may att
time pe
potentia
maximu
probabi
compac
burrow
the burr
D.8. Maxim
esa Mill Sit
Species
ouse
ouse
use
o rat
ottontail
ed weasel
kunk
prairie dog
g owl
Pocket Goph
SOIL REQUI
e two key co
is to select
e second is t
long term b
re a number
bility in sem
dium levels
trient conce
ents levels f
d plant grow
cover soil c
er, with pote
species (s
nity for prai
may be red
ract badgers
eriods beyon
al to burrow
um burrowin
lity of this
ction zone be
below this d
rowing depth
mum Burrow
e During th
Max
Aban
Aban
Most c
use bu
Ab
er
REMENTS
omponents t
long-lived s
to provide a
by supplying
r of soil cha
mi-arid enviro
, percent or
ntrations, av
for most of th
wth. In addit
ollected from
ential change
see discuss
rie dog colo
duced and b
s and the pr
nd 200 year
20-30 cm in
ng depth of
extensive b
eginning at
depth, and th
h of its prey.
w Depths fo
e Required
ximum Depth
30
34
60
48
34
ndoned burro
surface nes
ndoned burro
surface nes
90
228
122
100
common beha
rrows of othe
like the badg
bandoned bur
182
FOR SUSTA
to establishi
species that
cover soil th
g plants with
aracteristics
onments an
rganic matte
vailable wate
hese soil pro
tion, the tab
m stock piles
D-16
es in climate
sion under
nization on
bare ground
obability of b
rs. If this co
nto the rado
f the speci
burrowing is
a depth of 1
he burrowing
or Wildlife th
Performan
h (cm)
ws and
st
W
ws and
st
J
V
avior is to
er animals
ger
rrows
W
AINABLE P
ng an ET co
are adapted
hat will funct
h adequate
that are par
d include th
er, texture, b
er holding ca
operties that
ble includes
s at the Whit
Updated T
e and a trans
climate cha
the tailings
may increa
burrowing a
ondition occ
on attenuatio
es. Howev
low becau
122 cm, the
g depth of b
hat Inhabit
nce Period o
Cary 1911
Reynolds and
Reynolds and
Reynolds and
Reynolds and
Wilson and R
Chapman an
Feldhammer
Jackson 196
Lindsey 1976
Verdolin et al
Feldhammer
http://carnivo
Haug et al. 19
Wiscomb and
LANT GRO
over with a s
d to the env
tion as an ef
amounts of
rticularly imp
he following
bulk density
apacity, and
t are conside
soil property
te Mesa Mill
Tailings Cov
sition to dom
ange) there
cover syste
se. Prairie
nimals may
curs, then b
on layer stric
ver, it is b
se of the p
fact that pra
badgers will
or may Inha
of at Least 2
Source
d Wakkinen 1
d Laundre 19
d Laundre 19
d Wakkinen 1
Reeder 2005;
d Willner 197
et al. 2003
1
6
l. 2008
et al. 2003
ra.com/topic/
993
d Messmer 20
OWTH
sustainable
vironmental
ffective plan
water, nutri
portant to a
: pH, elect
y, cation exc
d soil microo
ered necess
y levels from
site in May
er Design R
MWH America
Augus
minance by w
e may be
em because
dog coloniz
likely increa
badgers hav
ctly based o
believed tha
placement o
airie dogs w
be influence
abit the Wh
200 Years
1987
988
988
1987
78
/932884/1/
010
plant comm
conditions o
nt growth me
ients and ro
chieve long
trical conduc
change cap
organisms. T
sary for long
m soil sampl
2009.
Report
as, Inc.
st 2012
warm
more
plant
zation
ase in
e the
on the
at the
of the
ill not
ed by
hite
unity.
of the
edium
ooting
-term
ctivity
acity,
Table
-term
les of

Denison M

The soil
growth in
phospho
include: p
Cation ex
cover so
content a
the recla
cover de
range sh
Table
Growth
Soi
pH (units)
EC (mmh
Sodium a
Organic m
Texture (%
Bulk dens
Water hol
(cm H2O/c
Cation ex
(meq/100
Total nitro
Extractab
(mg/kg)
Extractab
(mg/kg)
†Calculate
In order
sustainab
organic m
improve
matter w
combinat
ratio for s
as Bioso
These a
cycle nut
D.7 S
D.7.1 C
Climate
increases
In the co
ines Corp.
properties o
nclude: pH,
rus. Those
percent orga
xchange cap
oil will have
and a recom
amation proc
sign and wil
own in Table
D-9. Soil P
, Along with
l Property
)
os/cm)
dsorption rati
matter (%)
%)
sity (g/cm3)
ding capacity
cm soil)
change capa
g)
ogen (%)
le phosphoru
le potassium
ed values
for the po
ble support f
matter conte
available wa
will depend u
tion of manu
sustained pl
l® which has
mendments
trients over t
SUSTAINAB
Climate Cha
change pre
s in tempera
oming centur
of the potent
EC, sodium
e soil proper
anic matter,
pacity was n
an acceptab
mmendation
cess. Bulk
l be controlle
e D.9.
Properties a
h Analytica
Le
Sus
6.
o
1.
35 to
1.
y 0.0
city 5
0.0
s 6
60
otential cove
for the vege
ent, nitrogen
ater holding
upon availab
ure and hay
lant growth.
s been succ
would also
time and ens
ILITY OF TH
nge
dictions in t
ature (USGC
ry, mean glo
tial cover so
m adsorption
rties that ap
total nitroge
not measured
ble level for
that an orga
density of th
ed during th
and Their Ra
l Results of
White
evel for
tainability
.6 to 8.4
≤4.0
≤12
.5 to 3.0
o 50% clay
.2 to 1.8
08 to 0.16
5 to 30
05 to 0.5
6 to 11
0 to 120
er soil to f
tation compo
and potass
capacity an
bility in the re
to provide a
A third opt
cessfully use
o provide a
sure sustain
HE COVER
the southwe
CRP 2009) a
obal tempera
D-17
oil that are a
n ratio (SAR
ppear to be
en, and extra
d in the pote
r sustained
anic matter
he emplaced
e constructio
ange of Val
f Soil Availa
Mesa Mill S
Refe
Munshowe
Munshowe
Munshowe
Brady (197
Brady (197
Brady (197
Brady (197
Munshowe
Harding (1
Ludwick an
(1976)
Ludwick an
(1976)
function as
onent of the
sium levels.
nd cation exc
egion and c
a material tha
tion would b
ed in mined l
source of s
able plant g
DESIGN
est suggest
and decreas
ature could i
Updated T
acceptable fo
R), percent c
deficient an
actable potas
ential cover s
plant growth
amendment
d cover mat
on process t
ues Importa
able for ET
Site
erence
er (1994)
er (1994)
er (1994)
74)
74)
74)
74)
er (1994)
954)
nd Rogers
nd Rogers
a normal
e ET cover, it
An organic
change capa
could either
at has the ap
be the use of
land reclama
soil microorg
rowth.
warming in
ses in precip
ncrease sig
Tailings Cov
or sustaining
clay content,
nd would ne
ssium.
soil, but it is
h based on
t be added t
terial will be
to be within
ant for Sust
Cover Cons
Level
On-Sit
7.7 to
<1
<0
0 to
36 to 50
1.59 to
0.084-
Not me
0.02 to
10 to
11 to
soil and p
t will be ame
c matter ame
acity. The s
be compost
ppropriate c
f a commerc
ation over th
ganisms tha
n the region
pitation (Sea
nificantly, w
er Design R
MWH America
Augus
g long-term
, and extrac
eed improve
believed tha
the percent
to the soil d
e specified i
the sustaina
tainable Pla
struction at
ls for
te Soil
o 8.1
.5
0.5
0.4
0% clay
o 1.99†
-0.14†
easured
o 0.05
o 57
o 36
rovide long
ended to imp
endment wil
source of org
ted biosolids
arbon to nitr
cial product
he past 30 y
at will functio
n, with signif
ager et al. 2
ith an assoc
Report
as, Inc.
st 2012
plant
ctable
ement
at the
t clay
during
n the
ability
ant
t the
-term
prove
l also
ganic
s or a
rogen
such
years.
on to
ficant
2007).
ciated

Denison M

increase
Bryant 2
biologica
evolution
function
The clim
indicate
droughts
argue tha
poleward
mainly b
divergen
transient
Climate,
vegetatio
nutrient
influence
interactio
whether
climate c
current a
involved.
affect glo
the most
biotic inte
Predicted
atmosph
seasona
variability
the regio
caused s
juniper w
examined
They sho
aridity re
100 year
estimates
as pinyo
reduced
The spec
include i
and redu
efficiency
at each s
the abiot
dioxide, t
plant lev
ines Corp.
in the freq
008; Krawch
al response,
nary change
may be sign
ate model e
that continu
s. Analysis o
at increasing
d expansion
being driven
ce due to c
eddies.
more than a
on. At finer
status, pH,
e the potent
ons, such a
an individua
change asso
and future v
. Sala et al
obal biodive
t important d
eractions (in
d changes
eric concen
lity, and dis
y in climate
on more seve
substantial d
woodland in
d correlation
ow that con
lative to oth
rs, combined
s for the 21s
on pine. T
growth rates
cific physiolo
ncreased ne
uced stoma
y (Patterson
stage of the
tic factor mo
temperature
el in terms
uency of ex
huk et al. 20
especially
e, impacts o
nificant.
estimates an
ued warming
of the result
g aridity in th
of the sub
by a decli
changes in m
any other fa
scales, othe
water-hold
ial presence
s competitio
al plant is a
ociated with
vegetation p
. (1997) ide
rsity over th
driver of cha
vasive spec
in climate
trations of C
stribution of
patterns. R
ere than the
die-off of pin
the Four C
ns between
nifer trees in
er regions.
d with Interg
st century to
hey conclud
s and increa
ogical effects
et photosyn
tal conducta
and Flint 19
ir life cycle (
ost limiting t
e, and soil m
of growth a
xtreme even
009). If the
the capaci
on species
alyzed by C
g could prod
ts of 24 diffe
he southwes
tropical dry
ne in winte
mean atmos
actor, contro
er factors su
ing capacity
e or absenc
on for resou
actually foun
increasing
patterns. O
entified five d
he next 100
ange, followe
cies) and dire
that may o
CO2, increas
precipitation
Recent tempe
natural drou
nyon pine tre
Corners regio
climate and
n the south
They used
governmenta
predict the
ded that wo
ase mortality
s of increas
nthesis, redu
ance which
990). Ambie
(Morison and
o vegetation
moisture effe
nd resource
D-18
nts, such as
rate of glob
ty of popula
distributions
Cayan et al (2
duce increas
erent circula
st would be a
zones as t
er precipitati
spheric flow
ols the broad
uch as local
y and the
ce of a spec
urces (light,
nd at any p
greenhouse
Other human
different driv
years. Glo
ed by climat
ect CO2 fertil
occur in the
sed surface
n, more freq
erature incre
ughts of the
ees in appro
on (Breshea
d the radial
west are pa
climate-tree
al Panel on
likely fate o
oodlands an
at many so
ing GHG em
uced photore
decreases
ent tempera
d Lawlor 19
n, especially
ects on plan
e acquisition
Updated T
s droughts (
bal climate c
ations to m
s, communit
2010) and S
sed aridity,
ation models
an expected
the planet w
on associat
and reduce
dscale distri
l environme
physical el
cies. Howe
water, nut
particular loc
e gas emiss
n-influenced
vers of chan
obally, land
te change, a
lizing or wat
e southwest
e temperatur
quent clima
eases have
last several
oximately 4,
ars et al. 20
growth of t
articularly s
e growth rela
Climate Ch
of important
nd forests w
uthwest site
missions (pa
respiration, c
transpiratio
ature affects
999). Water
y in arid and
t physiology
. In additio
Tailings Cov
(IPCC 2007
change exce
migrate or u
ty structure
Seager and
overprinted
s lead Seag
d outcome th
warms. Sou
ted with inc
ed moisture
butions of p
ntal conditio
ements of
ever, intra- a
rients), ultim
cation (Syke
ions (IPCC
factors are
nge that can
use change
airborne nitr
ter use effici
tern U.S. in
res, change
atic extremes
made the c
centuries.
600 square
005). Willia
trees across
ensitive to
ations calcul
hange (IPCC
southwest tr
will experien
es as the cen
articularly CO
changes in
on and incre
plants direc
(i.e. soil mo
d semi-arid
y are exhibit
on to the ind
er Design R
MWH America
Augus
; Westerling
eeds the pa
undergo ada
and ecosy
Vecchi (201
by more se
er and Vecc
hat results fr
uthwest dryi
creased moi
convergenc
plant species
ons including
aspect or s
and inter-sp
mately deter
es 2009). R
2007) influe
e, however,
n be expect
e was consid
rogen depos
ency effects
nclude incre
s in the am
s, and a gr
current droug
This drough
miles of pin
ams et al. (2
s North Ame
temperature
lated for the
C) climate m
ree species
nce substan
ntury progres
O2) on veget
dark respira
eases water
ctly and indi
oisture) is us
regions. Ca
ted at the w
dividual effec
Report
as, Inc.
st 2012
g and
ace of
aptive
ystem
0) all
evere
chi to
rom a
ing is
isture
ce via
s and
g soil
slope
pecific
rmine
Rapid
ences
also
ted to
dered
sition,
s.
eased
mount,
reater
ght in
ht has
nyon-
2010)
erica.
e and
e past
model
such
ntially
sses.
tation
ation,
r use
rectly
sually
arbon
whole-
cts of

Denison M

increasin
and ecos
Plants ar
activity (
ecosyste
Changes
world (B
2003). P
Specific
among s
coexisten
resource
influence
as photo
Shifts in
temperat
Hutchin
competit
(Owensb
1992) is
In an effo
(2012a)
conseque
dominate
sites stra
rich. Th
latitude d
than eith
snow vs
seasona
accumula
Increasin
could sh
storage
dominate
substant
the semi-
condition
suggest
much sno
warming
decrease
become
addition,
a shift in
shift awa
(Schlaep
ines Corp.
ng temperatu
system-level
re finely tun
(i.e. phenolo
ems are be
s in the phen
radley et al
Phenology o
timing is cr
species in
nce in diver
es. Global cl
es the timing
period.
the relative
tures, or so
1991; Neil
ive ability o
by et al. 199
limiting.
ort to improv
used a soi
ences of ch
ed by big sa
atified along
e study incl
dry regions
er high elev
s. rain, is
lity. Ecosy
ated in a s
ng evaporat
ift the seaso
in snowpac
ed (with gen
ial impacts
-arid wester
ns described
no dramatic
ow to begin
, these dry
e. Marginal
unsuitable f
if seasonali
the water b
ay from deep
pfer et al. 20
ures, CO2 is
process (Lo
ed to the se
ogy) provide
eing influenc
nology of pla
. 1999; Fitte
of plant spe
rucial to op
their phen
rse plant co
imate chang
g of developm
e competitiv
il moisture
son and M
of C4 plants
99), especia
ve forecasts
l water sim
hanges in s
agebrush.
a climatic g
uded sites i
face consid
vation or arc
of lesser i
ystem wate
snowpack a
ive demand
onal hydrolo
k or wet w
nerally dry s
on vegetatio
n U.S. unde
d by the sno
changes in
with (which
to medium
areas near
for big sage
ty of precipi
balance from
p rooted shr
12a; Lauenr
s the additio
ong and Hut
easonality of
e some of
ced by glob
ants have b
er and Fitte
ecies is impo
ptimal seed
ology is a
ommunities
ge could sign
ment, both a
ve ability of
may result
Marks 1994)
s (such as
ally where s
of plant resp
mulation mod
now accum
The authors
gradient from
in eastern U
derably differ
ctic regions.
mportance
er balance
and subseq
d during the
ogy of a syst
inter soils c
soils and pe
on composit
er declining s
ow-precipitat
the water ba
best describ
areas will li
the southern
ebrush ecos
tation shifts
m storage to
ubs like big
roth 1996; Sa
D-19
onal interact
tchin 1991).
f their enviro
the most c
bal environm
been noted i
er 2002; Wa
ortant both
set for indi
n important
by reducing
nificantly alte
alone and th
f plants tha
in changes
). Increas
grasses) re
soil moisture
ponses to fu
del to incre
ulation and
s examined
m dry, warm
Utah. Resul
rent conseq
Their resul
for ecosys
was relativ
uently melte
e cold seaso
tem from sto
creating a s
eriodic brief
tion. Implica
snow conditi
tion ratios.
alance of dr
bes the Whi
kely becom
n limit of its
systems in t
toward the w
pulse domi
sagebrush t
ala et al. 199
Updated T
ive effect on

onment, and
compelling
mental cha
n recent de
alther et al.
at the indiv
ividuals and
t mechanis
g competitio
er plant phe
hrough intera
at experienc
to their spa
ses in temp
elative to C3e (Neilson 1
uture climatic
ease the lev
melt for w
120 rando
m and snow
lts from thei
quences from
lts indicate t
stem water
vely unaffe
ed or stead
on, caused
orage-domin
season with
wet pulses)
ations for b
ons depend
The results
ry to medium
te Mesa Mil
e even drie
range (such
he future (S
warm seaso
inated with a
to shallower
97).
Tailings Cov
n photosynt
d shifts in th
evidence th
ange (Clelan
ecades in reg
2002; Parm
vidual and p
d population
sm for main
on for pollin
enology beca
actions with
ce changes
atial distribu
perature ma
3 plants (sh
1993) or tem
c conditions
vel of unde
water balanc
omly selecte
poor to wet
ir analysis s
m changing
that the form
balance th
ected by w
dily infiltrate
by increase
nated (with s
reliably we
), a change
ig sagebrus
d on the area
of Schlaepf
m areas, bec
l site). How
er and veget
h as southea
Schlaepfer e
on, these are
an accompa
r rooted spe
er Design R
MWH America
Augus
hetic produc
he timing of
hat species
nd et al. 2
gions aroun
mesan and
population le
ns; and var
ntaining sp
nators and
ause temper
other cues,
in CO2, su
ution (Long
ay enhance
hrubs and t
mperature (E
Schlaepfer
erstanding o
e in ecosys
ed big sageb
t, cold and
showed that
snow cond
m of precipita
han precipit
whether wat
ed into the
ed temperat
substantial w
et soils) to
that would
sh ecosystem
a-specific cli
fer at al. (20
cause there
wever, becau
tation activit
astern Utah)
et al. 2012b
eas may und
anying veget
ecies like gra
Report
as, Inc.
st 2012
ctivity
plant
s and
2007).
d the
Yohe
evels.
iation
ecies
other
rature
such
urface
g and
e the
trees)
Esser
et al.
of the
stems
brush
snow
t mid-
itions
ation,
tation
er is
soil.
tures,
water
pulse
have
ms in
matic
012a)
is not
use of
ty will
) may
b). In
dergo
tation
asses

Denison M

In a tota
(1994) an
future ch
the great
challengi
required
as to po
logical an
processe
cover sy
Natural a
evolution
predictio
reconstru
lake sedi
Waugh a
past but
of global
inadequa
year des
Ranges
inferred
condition
and Late
Waugh a
drivers o
those as
glacial a
possible
performa
climate re
80 cm m
precipitat
anticipate
and wett
period th
analog a
the level
develope
future ch
approach
work is n
Based o
U.S. is fo
winter p
accompa
is correc
shallow r
ines Corp.
ally different
nd Waugh (2
hanges. The
test uncertai
ing need to
by regulato
ossible long-
nalogy to inv
es that are s
ystem. As s
analog studie
n of enginee
ns extrapola
ucted past c
iment pollen
and Petersen
also on pos
and regiona
ate for local
ign life of ta
of possible
from natura
ns 1,000 yea
er Pleistocen
and Peterse
f future clim
sociated wit
and Altitherm
future clim
ance of taili
econstructio
mean annua
tion could a
ed to occur
ter compare
he climate w
approach pro
of resolutio
ed) that it b
hanges in ve
h in combina
needed befor
n the prece
or warmer c
precipitation
anied shift in
ct, there wou
rooted spec
t approach
2010) used
e authors se
inties in des
extrapolate
ry agencies
-term chang
vestigate nat
similar to tho
such, analog
es are valua
ered covers
ated from th
climate chan
, and archae
n (1994) rep
ssible local m
al climate ma
climate proje
ilings reposi
future clima
al proxy reco
ars into the f
e according
n (1994) co
mate change,
th the last g
mal climates
mate and
ngs disposa
ons provide w
al precipitati
also occur a
approximate
ed to curren
would be slig
ovides a uni
on is so coa
becomes ex
egetation fo
ation with clim
re these too
ding review
conditions an
may dec
n the water b
uld be a cha
ies like gras
to making
past climate
elected a nov
igning cover
the results
. Natural an
ges in engin
tural and arc
ose known o
gs can be t
able in unde
s that do no
he results o
ge using av
eological rec
port that pale
manifestation
ay enhance
ections. Re
itories are in
ate at tailing
ords of pas
future can be
to Waugh a
oncluded fro
, climate ext
glacial and in
s in the Fo
should be
al facilities.
working leve
ion. If we
at the White
ely 60,000 ye
t conditions
ghtly warme
que method
arse (based
tremely diffi
or the White
mate models
ls can be ap
, the most c
nd greater e
rease and
balance from
ange over ti
sses. In ad
D-20
climate cha
e change as
vel approach
rs for tailings
of short-term
nalog studie
neered cove
chaeologica
or predicted
thought of a
rstanding an
ot arise dur
of short-term
vailable proxy
cords from th
eoclimatic re
ns of future
our underst
egional clima
ncapable of r
gs disposal
t climate ch
e captured w
and Petersen
m their inve
tremes in th
nterglacial p
our Corners
incorporate
For Monti
els of 2 to 10
assume tha
Mesa Mill s
ears into the
, and if con
r and wette
d for making
on the larg
icult and hig
e Mesa Mill
s may be the
pplied with a
consistent v
evaporative l
summer
m winter stor
ime from de
dition, with
Updated T
ange project
an analog o
h to climate
s repositorie
m tests to th
es provide cl
ers. Analog
l occurrence
to occur in
as uncontro
nd evaluatin
ring short-te
m tests. W
y data from
he Four Cor
ecords provi
global chan
tanding of cl
ate models t
resolution on
sites the F
hange. A r
within a perio
n (1994) and
estigation th
e next 1,000
periods. The
s region pro
ed in asse
cello, Utah,
0o C mean a
at a similar
site, then d
e future the
nditions post
r than curre
g projections
ge temperatu
ghly unrelia
site or any
e most effec
reasonable
view of clima
loss of wate
precipitation
rage to pulse
eep rooted s
continual in
Tailings Cov
tions, Waug
of possible lo
change pre
es stem from
he long perf
lues from pa
g studies inv
es of materia
some part o
lled, long-te
ng emergent
erm tests or
Waugh and
tree rings, p
rners Region
de not only
nge. By com
imate-chang
hat could ad
n the spatia
Four Corners
reasonable r
od of spann
d Waugh (20
at despite u
0 years likel
erefore, pale
ovide reaso
essments o
, full glacial
annual tempe
r range of t
uring the ne
climate wou
t-glaciation
ent condition
s 1,000 year
ure and pre
able to mak
y waste faci
ctive path for
e degree of c
ate change
er. It also ap
n may inc
e dominated
species like
creases in a
er Design R
MWH America
Augus
gh and Pete
ocal respons
edictions bec
m the scientif
formance pe
ast environm
volve the us
als, condition
of the engine
erm experim
properties i
r from nume
Petersen (1
packrat midd
n.
a window o
mparison, mo
ge drivers bu
ddress the 1
l scales requ
s region ma
range of cli
ing the Holo
010).
uncertainty a
y will not ex
eo-records o
nable range
of the long
l and Altithe
erature and
temperature
ext glacial p
uld be a lot c
result in a w
ns. Althoug
rs into the fu
ecipitation ra
ke prediction
lity. The an
rward, but fu
confidence.
in the south
ppears likely
crease, with
d. If this sce
shrubs, to
atmospheric
Report
as, Inc.
st 2012
ersen
ses to
cause
fically
eriods
ments
se of
ns, or
eered
ments.
in the
erical
1994)
dens,
on the
odels
ut are
,000-
uired.
ay be
matic
ocene
about
xceed
of full
es of
-term
ermal
38 to
e and
phase
colder
warm
h the
uture,
anges
ns on
nalog
urther
hwest
y that
h an
enario
more
c CO2

Denison M

there wo
advantag
possible
resulting
From the
the impa
commun
a comm
dominan
increase
D.7.2 P
Plant suc
beginning
dominate
successi
as in som
place.
Two com
increase
implicatio
vegetatio
proceeds
(e.g., gra
(strata) o
processe
replaced
and type
layers.
ines Corp.
uld be a shi
ge to warm
climate sce
plant comm
e review of c
act of variou
ity type that
munity domin
ce by warm
and precipit
Plant Comm
ccession is
g with relat
ed by long-li
on can be re
me desert an
mmon aspec
in the rela
ons to the fu
on, e.g., he
s, both abov
asses may b
of vegetation
es occur bel
by deeper-
es of specie
ift in compet
season gra
enarios for th
munity type
climate chan
s climate ch
will be main
nated initial
m season g
tation decrea
unity Succe
the ecologic
ively-short l
ved, genera
elatively rap
nd arctic reg
cts of succe
ative amoun
unction of c
eight, cover
ve- and belo
be replaced
n occurs, wi
lowground.
rooted spec
es increase,
titive advant
asses over c
he White M
that would
ge literature
hange scena
ntained thro
lly by cool
grasses as
ases and sh
ession and
cal process
ived herbac
ally woody sp
id, especiall
gions, but th
ession are
nts of wood
cover system
rage, and
wground. A
by shrubs),
ith different
Root syste
cies, root bio
and the de
D-21
tage to C4 ov
cool season
esa Mill site
develop du
e applicable t
arios, it is o
ughout the 2
season gr
atmospher
hifts from win
Potential fo
of direction
ceous plants
pecies. Suc
y in regions
is process o
1) an incre
dy plants.
ms. Vegetat
stratification
Aboveground
coverage of
species occ
ems become
omass increa
ensity of the
Updated T
ver C3 spec
n shrubs. T
e, their likeli
uring the re
to the south
our conclusio
200 to 1,000
rasses, with
ric CO2 and
nter storage
or Species
al vegetatio
s and culmi
ccession occ
s of higher ra
of vegetation
ease in veg
Both of the
tion structur
n. Structure
d, the height
f the soil sur
cupying diffe
e deeper as
ases in lowe
e root syste
Tailings Cov
ies, which w
Table D.10 p
ihood of occ
equired perf
west U.S. a
on that the
0 year perfo
h a long-te
d temperatu
to pulse dom
Colonizatio
on change o
nating in pl
curs on all s
ainfall, or it c
n change is
etation stru
ese aspects
re refers to
e increases
t of the vege
rface increas
erent vertica
s shallow-roo
er soil depth
em increase
er Design R
MWH America
Augus
would give fu
presents a l
currence an
formance pe
nd an analy
most likely
ormance per
erm transitio
ure continue
minated.
on
over time, us
lant commu
sites. The ra
can be very
constantly ta
cture and 2
s have prof
the shape o
s as succe
etation incre
ses, and lay
al layers. S
oted specie
hs as the nu
es in the va
Report
as, Inc.
st 2012
urther
list of
d the
eriod.
sis of
plant
iod is
on to
es to
sually
nities
ate of
slow,
aking
2) an
found
of the
ssion
eases
yering
imilar
s are
mber
arious

Denison M

Tabl
Occurre
Possib
Sce
Warmer a
than Pres
Warmer a
than Pres
Warmer th
with Simil
Precipitat

Cooler an
Present4
Cooler an
Present5
Cooler tha
with Simil
Precipitat

Dryer than
with Simil
Temperat
Wetter tha
with Simil
Temperat
1Results i2Results i
summer m3Results i4Results i5Results i6Results i7Results i8Results i9Likelihoo
and Seag
As the v
relatively
by wood
proportio
Early suc
upper so
depth.
Because
cover ar
construct
ways, co
ines Corp.
e D.10. Pos
ence and Pr
G
ble Climate
enarios
and Dryer
sent1
and Wetter
sent2
han Present
ar Total
ion3
nd Wetter than
nd Dryer than
an Present
ar
ion6
n Present
ar
ture7
an Present
ar
ture8
n less total pr
n more total
months.
n no change
n more total p
n less total pr
n no change
n less total pr
n more total p
od of occurren
er and Vecch
vegetation s
y shallow roo
dy species
onately more
ccessional p
oil profile. L
This can be
e of success
re likely to
tion are not
onditions wi
ssible Clima
rojected Ch
Grass/forb C
Likelih
Occur
Highly Lik
Unlikely
Unlikely

n Highly Un
Highly Un
Highly Un

Unlikely
Unlikely
recipitation bu
precipitation
in total precip
precipitation w
recipitation bu
in total precip
recipitation.
precipitation.
nce based on
hi 2010, with a
shifts from d
ot systems b
(e.g., shr
e roots in de
plant commu
Late success
e both a po
sional chang
become ve
likely to be s
ill be more
ate Scenari
hange in Pla
Community
hood of
rence9
kely G
s
W
m
c
p
t
G
s
nlikely S
w
nlikely S
w
nlikely S
w
G
s
a
S
p
ut shift to less
with shift to le
pitation but sh
with shift to m
ut shift to mor
pitation but sh
n majority of
a focus on the
dominance
but with very
rubs and t
eeper layers
unities tend
sional comm
ositive and
ges in the v
ery different
similar to tho
favorable,
D-22
ios for the W
ant Species
y Establishe
Projected P
Seeded
Grass/forb co
species.
Will depend o
more precipita
community wo
plants; if more
the plant com
Grass/forb co
species.
Shift to more
winter months
Shift to more
winter months
Shift to more
winter months
Grass/forb co
species beca
atmospheric C
Shift to more
precipitation.
s snow and m
ess snow and
hift to less sno
more snow in w
re snow in win
hift to more sn
climate mode
e southwest U
by herbaceo
y dense root
trees), whic
s, the hydrol
to extract m
munities hav
a negative
vegetation,
over time.
ose soon aft
e.g., evapo
Updated T
White Mesa
s Compositi
ed on the So
lant Commu
Grass/Forb
ommunity with
on distribution
ation in winte
ould experien
e precipitation
mmunity would
ommunity with
woody plants
s.
woody plants
s.
woody plants
s.
ommunity with
use of less ov
CO2.
woody plants
more rain in wi
d more rain in
ow and more
winter months
nter months
now in winter
el estimates
U.S.
ous plants
mass in the
ch have d
logical dyna
most of the w
ve greater a
in the fun
the plant-so
Condition
er construct
otranspiratio
Tailings Cov
a Mill Site, L
on Compar
oil Cover
nity Type in
as the Initia
h an increase
n of additional
er months, the
nce an increa
n in the summ
d continue as
h an increase
s because of
s because of
s because of
h an increase
verall moistur
s because of
inter months.
n winter mon
rain in winter
s.
months.
analyzed by
(e.g., grass
e upper profi
eeper roots
amics of the
water they tr
ability to ex
ctional effic
oil-water cha
ns 200 year
tion was com
n will likely
er Design R
MWH America
Augus
Likelihood o
red to the In
1,000 Years
l Community
in warm sea
l precipitation
en the plant
se in woody
mer months, t
a grass/forb
in warm sea
more snow in
more snow in
more snow in
in warm sea
re and increas
more winter
ths or more r
r months.
Cayan et al.
ses), which
ile, to domin
s systems
system cha
ranspire from
xtract water
ciency of co
aracteristics
rs or more
mpleted. In s
y be higher
Report
as, Inc.
st 2012
of
nitial
with
y
son
n. If
hen
type.
son
n
n
n
son
se in
rain in
2010
have
nance
with
ange.
m the
from
overs.
of a
after
some
thus

Denison M

reducing
ways, co
reach the
these cha
As state
following
cm of a w
highly co
The prop
potential
system is
in combin
among s
climax co
current c
estimated
commun
However
Mesa are
site and
plant com
time will
higher CO
terms of
vegetatio
may esta
from 132
state (Kle
compacte
below the
other pla
As discus
changes
percenta
establish
and big s
establish
species
rabbitbru
the next
sagebrus
plant com
seeded s
most like
from coo
only 10 t
and galle
have mig
ines Corp.
the amount
onditions wil
e buried tail
anges have
d earlier, th
layers from
water storag
ompacted ra
posed cove
intrusion by
s designed t
nation with a
species likely
ommunity fo
community ty
d that it may
ity (McLend
r, if the most
ea occurs ov
a grassland
mmunity type
most likely
O2 condition
f plant succ
on and soil c
ablish on the
2 cm on site
epper et al.
ed radon at
e compacted
nt species th
ssed above,
in species
ge of potent
hing during t
sagebrush w
hed commun
at end of th
ush, broom s
100 years th
sh will begin
mmunity will
species will
ely continue
ol season to
to 20% of th
eta. The re
grated north
t of deep inf
l be less fa
ings. Becau
been accou
he proposed
m top to botto
ge, biointrus
don attenua
er system d
y plant roots
to minimize
a highly com
y to inhabit t
or the White
ype at the si
y take 25 to
on and Red
t likely clima
ver the next
d community
e to remain.
consist of w
ns and a puls
cession or
conditions th
e proposed c
es in Utah (W
1985). Th
ttenuation la
d zone will a
hat is likely t
, the process
s compositio
tial species c
he first 50 to
would be the
nity will cons
he first 100
snakeweed,
he plant com
n to diminish
consist of 5
be warm se
through the
o warm seas
e original se
mainder of t
with the war
filtration and
avorable, e.g
use success
unted for in t
d cover syst
om: 15 cm
sion and rad
ation layer ov
oes not co
s during the
plant root in
mpacted laye
the site duri
e Mesa Mill
te and the re
o 50 years fo
dente 1990;
ate change s
t 200 to 1,00
y dominated
. It is theref
warm seaso
se dominate
climate cha
hat big sage
cover system
Weaver and
e thickness
ayer located
all contribute
to colonize t
s of success
on in the ta
colonization
o 100 years
e primary inv
sist of 60 to
years. The
and a few g
mmunity will
h. By the e
50% seeded
eason plants
remainder o
son species
eeded speci
the commun
rming climat
D-23
stability of
g., deeper r
sion is a pro
he cover des
tem is a m
of a topsoil-
don attenuat
ver 76 cm o
ntain a bio
required pe
ntrusion thro
er placed at
ng the 200
site is belie
elatively dee
or sagebrus
Newman an
scenario of a
00 years, it i
d by warm s
fore forecast
on species t
ed precipitati
ange, there
ebrush would
m. Maximum
Clements 1
of the cove
at a depth
e to preventi
he site.
sion and the
ailings cove
would be fo
s. The seed
vader into th
o 70% seed
ese non-seed
grass and fo
begin to tra
nd of the se
and 50% no
s and most o
of the perfor
s, a complet
es still prese
nity would c
te.
Updated T
the vegetati
root systems
ocess that is
sign.
onolithic ET
-gravel erosi
ion layer ov
of a grading
barrier (e.g
erformance p
ough the use
a depth tha
to 1,000 ye
eved to be B
ep fine loam
sh to coloniz
nd Redente
a warmer an
is unlikely th
season spe
ted that pote
that will be
on regime. R
is ample e
d be the mo
m rooting de
1938) to 200
er (total of 3
below 122
ing biointrus
effect of cli
er system.
or a small pe
ded commun
he cover sys
ed species
ded species
orb species c
ansition to w
econd 100 y
on-seeded s
of these will
rmance perio
te dominanc
ent and thes
consist of wa
Tailings Cov
ion may be
s may have
s near-unive
T cover that
ion protectio
ver up to 110
and radon a
. cobble lay
period. The
e of thick lay
at is below th
ar performa
Big Sagebru
my soils that
ze the estab
2001; Pasc
nd dryer clim
hat sagebrus
cies may be
ential specie
the most c
Regardless
evidence ba
ost deep roo
pths for big
0 cm on site
308 cm), the
cm, and a f
sion by big s
mate chang
Our best
ercent of non
nity will be h
stem. It is e
and 30 to 4
s will include
common in t
warm season
years it is es
species and
l be grasses
od with a co
ce by grass
se would inc
arm season
er Design R
MWH America
Augus
greater. In
e the potent
ersal ecologi
t consists o
on layer ove
0 to 136 cm
attenuation l
yer) to min
e proposed c
yers of soil c
he rooting de
ance period.
sh based o
are present.
blished grass
chke et al. 2
mate for the W
sh will rema
e the most
es invasions
ompetitive u
of what occu
ased on cu
oted species
sagebrush r
es in Washin
e use of a h
final 76 cm
sagebrush o
e will bring a
forecast fo
n-seeded sp
highly sustain
estimated tha
40% non-se
e big sageb
the area. D
n species an
stimated tha
many of the
s. This tren
omplete tran
ses, and pos
clude blue g
species tha
Report
as, Inc.
st 2012
other
tial to
ically,
of the
r 107
m of a
layer.
imize
cover
cover
epths
The
n the
. It is
s/forb
2003).
White
ain on
likely
s over
under
urs in
urrent
s that
range
ngton
highly
layer
or any
about
r the
ecies
nable
at the
eeded
brush,
During
nd big
at the
e non-
d will
sition
ssibly
grama
at will

Denison M

REFERE
Alderson
D
Bartos, D
M
Bradley,
ch
Brady, N.
Breshear
H
R
N
Burt, W.
C
Carnivora
Cary, M.
A
Cayan, D
so
N
Chapman
Cleland E
re
Cooke, R
B
Coupland
S
Dames a
U
DePuit, E
L
DePuit, E
la
C
E
ines Corp.
ENCES
, James an
Department o
Dale and Ph
Management
N. L., Leopo
hange in Wis
. C. 1974. T
rs, D.D., N.S
Hastens, M.L
Regional veg
National Acad
H. and R.
Company. Bo
a. 2012. http
1911. No
Agriculture. G
D., T. Das, D.
outhwest U.
National Acad
n, J. and G. W
E., I. Chuine
esponse to g
R. V. and A.
Berkeley, CA.
d, R. T. and
Saskatchewa
and Moore. 1
Utah. Prepare
Edward J. 1
loyd (ed.) Re
E. J. 1982.
ands: status
Coal Mining
Experiment S
nd W. Curtis
of Agriculture
hillip Sims.
27:33-36.
ld, A. C., Ro
sconsin. Proc
The Nature a
S. Cobb, P.M
L. Floyd, J.
getation die-
demy of Scie
P. Grossen
oston, MA.
p://carnivora
orth America
Government
. Pierce, T. P
S. and the h
demy of Scie
Willner. 1978
, A. Menzel,
lobal change
Warren. 19
.
R. E. Johns
n. J. of Ecol
1978. Enviro
ed for Energ
988. Produ
eclamation of
Cool-seaso
of current te
and Recla
tation Resea
s Sharp. 1
, Agriculture
1974. Root
ss, J. and W
ceedings of t
and Property
M. Rich, K.P
Belnap, J.J
off in respo
ences 102:15
nheider. 1980
.com/topic/93
an Fauna.
Printing Offic
Parnett, M. T
hydrology o
ences 107:21
8. Sylvilagus
H. Mooney,
e. Trends in E
973. Geom
son. 1965.
ogy 53:475-5
onmental Re
y Fuels Nucl
ctivity of rec
f Surface-Min
on perennial
echnology. P
amation in t
arch Report 1
D-24
994. Gras
Handbook N
t dynamics o
W. Huffaker. 1
the National
of Soils. 8th
P. Price, C.D
J. Anderson
onse to glob
5144-15148.
0. A field g
32884/1/. Si
Biological S
ce. Washing
yree, and A.
the early 21
271-21276.
s audubonii.
and M. Sch
Ecology and
orphology in
Rooting cha
507.
port—White
lear, Inc.
laimed lands
ned Lands V
grass estab
Pages B1-B2
the Norther
194. Bozema
Updated T
ss Varieties
No. 170. Wa
of a shortgra
999. Phenol
Academy of
h ed. MacMill
D. Allen, R.G
n, O.B. Mye
bal-change d
uide to the
ite accessed
Survey of Co
gton, D.C.
Gershunov.
1st century
Mammalian
hwartz. 2007
Evolution 22
n Deserts. U
aracteristics o
Mesa Uraniu
s—rangeland
Vol II. CRC P
lishment on
24 In Proceed
rn Great Pl
an, MT.
Tailings Cov
in the Unite
ashington, D.
ass ecosyste
logical chang
f Sciences 96
lian Press. N
G. Balice, W
ers, and C.W
drought. Pro
mammals.
d in July 2012
olorado. U.S
. 2010. Futu
drought. Pr
n Species No
7. Shifting p
2:357-365.
University of
of native gra
um Project, S
d. Pages 93
Press. Boca
Northern Gr
dings: Symp
ains. Mon
er Design R
MWH America
Augus
ed States.
C.
em. J. of R
ges reflect cl
6:9701–9704
New York, NY
W.H.Romme,
W. Meyer. 2
oceedings o
Houghton M
2.
S. Departme
ure dryness
roceedings o
o. 106. 4 pp.
plant phenolo
f California P
assland spec
San Juan Co
3-129 In Hos
Raton, FL.
reat Plains m
posium on su
ntana Agricu
Report
as, Inc.
st 2012
U.S.
Range
imate
4.
Y.
, J.H.
2005.
of the
Mifflin.
ent of
in the
of the
.
ogy in
Press.
cies in
ounty,
ssner,
mined
urface
ultural

Denison M

DePuit, E
co
m
B
DePuit, E
M
A
Esser, G
co
Fang, Ho
te
N
Feldhamm
m
Fitter, A.
2
Foxx, T.
In
In
Gill, Rich
ro
E
Groeneve
a
Harding,
o
Haug, E.
N
Hendricks
J
Hopkins,
M
Intergove
S
In
Jackson,
ines Corp.
E. J., J. G. C
ommunities
mixture and
Bozeman, MT
E. J., J. G. C
Mined Lands
Agricultural Ex
. 1992. Impli
oniferous for
ongliang, Shu
emporally co
North America
mer, G., B. T
management,
H. and R.
96:1689–169
S. and G. D
n Everett, R.
ntermountain
hard, Ingrid B
oot biomass
Ecosystems 2
eld, David. 1
rea index. J
R. B. 1954.
rchards. So
, D. Millsap,
North America
s, David M.
. (ed.) Semia
Harold 195
Management
ernmental Pa
Science Basis
ntergovernme
H. H. T. 196
Coenenberg,
on coal surf
rate. Mo
T.
oenenberg,
at Coalstrip
xperiments S
cations of cl
rests. Ecolog
unlin Liang, J
ontinuous LA
a. Remote S
Thompson, a
, and conserv
S. Fitter. 20
91.
. Tierney. 19
L. (ed.). P
n Forest and
Burke, Danie
and soil org
2:226-236.
1997. Vertic
. of Arid Env
. Surface ac
il Science So
and M. Mart
a. The Acad
1991. Gene
arid Lands an
53. Root
6:382-92.
anel on Clim
s. Contribut
ental Panel o
61. Mamma
and C. L. S
face mined
ntana Agric
and W. H. W
Montana: P
Station, Boze
imate chang
ical Applicat
John R. Tow
AI data sets b
Sensing of En
and J. Chapm
vation. John
002. Rapid
987. Rootin
Proceedings—
Range Expe
l Milchunas
ganic matter
cal point quad
ironments. 3
ccumulation
ociety of Ame
tell. 1993. B
demy of Natu
esis and clas
nd Deserts.
developmen
mate Change
tion of Work
on Climate C
als of Wiscon
D-25
Skilbred. 198
lands in Mo
cultural Expe
Willmuth. 197
Progress Rep
eman, MT.
e for produc
ions 2:47-54
wnshend and
based on int
nvironment
man. 2003.
n Hopkins Un
changes in
g patterns in
—Pinyon-Jun
eriment Statio
and William
pools in the
drat samplin
36:475-485.
of nitrates an
erica Procee
Burrowing ow
ural Sciences
ssification of
Marcel Dekk
nt of grasse
e (IPCC). 20
king Group I
Change.
sin. Univers
Updated T
80. Establis
ontana as inf
eriment Sta
78 Researc
port 1975—1
ction and dec
4.
d Robert Dic
tegrated filte
112:75-93.
Wild Mamm
niversity Pres
flowering tim
n the pinyon-
niper Confere
on. General
Lauenroth.
e shortgrass
g and an ext
nd other solu
edings. 18:36
wl. In Poule
s. Philadelph
arid region s
ker, Inc. New
es on reveg
007. Climate
to the Four
sity of Wiscon
Tailings Cov
shment of div
fluenced by
ation Resea
ch on Revege
977 Res. Re
composition
ckenson. 20
ring method
als of North
ss. Baltimore
me in British
-juniper wood
ence. USDA
Technical R
1999. Rela
steppe of E
xtinction facto
uble salts in
69-372.
e, A. and F. G
hia, PA.
soils. Pages
w York, NY.
getated land
Change 20
rth Assessm
nsin Press.
er Design R
MWH America
Augus
verse native
seeding me
rch Report
etation of Su
ep. 127. Mon
in grasslands
08. Spatially
: Examples
America: bio
e, MD.
h plants. Sc
dland. pp. 6
A Forest Se
Report INT-21
ationship bet
Eastern Colo
or to calculat
California or
Gill (eds.) Bir
s 33-79 In Sk
d. J. of R
007: The Phy
ent Report o
Madison, WI
Report
as, Inc.
st 2012
plant
ethod,
163.
urface
ntana
s and
y and
s from
ology,
cience
69-79
ervice.
15.
tween
orado.
e leaf
range
rds of
kujins,
Range
ysical
of the
I.

Denison M

Jackson,
a
Klepper,
in
R
Krawchuk
py
Lauenrot
C
Lee, C. A
sh
Lindsey,
Long, S.
cl
Ludwick,
S
McLendo
m
M
L
N
McLendo
in
Monsen,
W
R
Morison,
te
Munshow
R
Neilson,
m
Neilson,
se
A
re
ines Corp.
R., J. Cana
nalysis of roo
E., K. Gano,
n the 200 are
Richland, WA
k, M.A., Mo
yrogeograph
h, W. 1996.
Climate Chan
A. and W. K.
hortgrass ste
F. 1976. Ch
P. and P.R
limate chang
A. E. and J
State Univers
on, T. 2010
modeling of
Meeting pres
ow-Level Ra
NUREG/CP-0
on, T. and E.
n a sagebrus
Stephen. B.
Wildlands. U
RMRS-GTR-1
J. I. L., and
emperature o
wer, Frank. 1
Raton, FL.
R. P. 1993
modelling app
R. P. and D
ensitivities fr
And E. F. Re
evegetation t
adell, J. Ehle
ot distribution
and L. Cadw
ea Control Zo
A.
oritz, M.A.,
hy: the curren
Application
nge 34:155-1
Lauenroth.
eppe. The A
haracteristics
R. Hutchin. 19
ge: an overvie
J. R. Rogers
ity Agricultur
0. Effects of
long-term su
entation from
adioactive W
0195, U.S. N
F. Redente
h steppe com
, Richard Ste
U.S. Departm
136-vol 1-3. R
Lawlor, D. W
on plant grow
1994. Practic
3. Transien
proaches. Ec
D. Marks. 19
rom climatic c
edente. 200
techniques.
eringer, H. M
ns for terrest
well. 1985.
one of the Ha
Parisien, M
nt and future
of patch mo
60
1994. Spat
American Mid
s of the Nata
991. Primary
ew. Ecologic
s. 1976. So
ral Extension
f plant succ
uccessional
m the Works
Waste, Deco
uclear Regu
. 1990. Sec
mmunity. Oe
evens and N
ment of Agri
Rocky Moun
W. 1999. Int
wth. Plant, Ce
cal Handboo
nt ecotone r
cological App
994. A glob
change. Jou
01. Long-te
J. Range Ma
D-26
Mooney, O.
rial biomes.
Rooting dep
anford Site.
M.A., Van D
distribution o
odels to exam
ial distributio
land Natural
l Den of the B
y production
cal Applicatio
oil test expla
n Service. Fo
cession on th
impacts us
shop on Eng
ommissionin
latory Comm
condary succ
ecologia 85:2
ancy L. Shaw
culture. Fo
ntain Researc
teractions be
ell & Environm
ok of Disturbe
response to
plications 3:38
al perspectiv
rnal of Vege
erm plant co
anage. 54:71
Updated T
Salsa and E
Oecologia 1
pths and distr
PNL-5247.
Dorn, J. &
of wildfire. PL
mine regiona
ons of grass a
list 132:117-1
Badger. Nor
in grassland
ons 1:139-156
anation. 502
ort Collins, C
he functionin
sing EDYS E
gineered Ba
g, and Ura
mission, Rock
cession patte
293-300.
w. 2004. Re
orest Service
ch Station. F
etween incre
ment 22:659
ed Land Rev
climatic ch
85-395.
ve of region
etation Scien
ommunity de
17-724.
Tailings Cov
E. Schulze.
08:389-411.
ributions of d
Pacific North
Hayhoe, K
LoS ONE 4:
al sensitivity t
and shrub ro
123.
rthwest Scie
ds and conife
6.
2 Service in A
O.
ng of engine
Ecological S
arrier Perform
anium Mill T
kville, Maryla
erns followin
estoring Wes
e. General
ort Collins, C
asing CO2 c
9-682.
vegetation. C
ange: some
nal vegetatio
ce 5:715-730
evelopment
er Design R
MWH America
Augus
1996. A g
.
deep rooted p
hwest Labora
K. (2009) G
e5102.
o climate cha
oot systems
nce 50:178-1
erous forests
Action. Colo
eered covers
Simulation M
mance Relat
Tailings Fac
and.
g soil disturb
stern Range
Technical R
CO.
concentration
CRC Press.
e conceptua
on and hydro
0. Newman,
as influence
Report
as, Inc.
st 2012
global
plants
atory,
Global
ange.
in the
180.
s with
orado
s and
Model.
ted to
ilities,
bance
s and
Report
n and
Boca
l and
ologic
G. J.
ed by

Denison M

Owensby
co
at
Parmesa
n
Paschke,
sh
D
Patterson
fo
B
E
a
S
Plummer
R
F
Redente,
su
R
Reynolds
B
Reynolds
U
Sala, O.,
re
T
U
Schlaepfe
a
1
Schlaepfe
cu
E
Scurlock,
A
Seager, R
A
to
ines Corp.
y, C.E., Ham
omposition c
tmospheric C
n, C. and G.
atural system
, M. W., E. F
hrubs on m
Development
n, D.T. and E
or plant com
B.A. Kimball,
Ernst, (eds.).
griculture. A
Soc.Am.
r, A. Perry, D
Range in Uta
ish and Gam
E. F., T. B.
uccession o
Research 3:15
s, T. and J.
Burrowing Ro
s, T. and W
Undisturbed S
W. Lauenro
egions. pp.
Types: The
University Pre
er, D., W.
ccumulation
0.1111/j.136
er, D., W. L
urrent and fu
Ecography 35
, J. M. O., G
Area Index, 19
R., Mingfang
A., Lau, N., L
o a more arid
m, J.M., Knap
change in a
CO2. Global
Yohe. 2003
ms. Nature 42
F. Redente,
mining distur
14:459-480.
E.P. Flint. 19
munities and
N.J. Rosen
Impact o
ASA Spec. P
Donald R. Ch
ah. Utah Div
me, Ephraim,
Doerr, C. E.
on disturbed
53-166.
Laundre, 1
odents in Dist
W. Wakkinen
Soils in South
oth, and R.
217-233 In
eir Relevanc
ess. Cambrid
Lauenroth,
for water ba
65-2486.2012
Lauenroth, an
uture ranges
5:374-384.
G. P. Asner,
932-2000. O
g, T., Held, I.
i, C., Velez,
d climate in s
pp, A.K. and
tallgrass pra
l Change Bio
3. A globally
21:37–42.
and S. L. B
bances in t
.
990. Implicat
d competitio
berg, L.H. A
f carbon dio
ubl. No. 53.
hristensen, a
vision of Fish
UT.
Grygiel, and
soils in no
988. Vertica
turbed and U
n, 1987. Bu
heastern Idah
Golluscio.
Smith, T., H
ce to Ecosy
dge, England
and J. Bra
alance of mi
2.02642.x.
nd J. Bradfo
s, local suitab
and S. T. G
Oakridge Nat
., Kushnir, Y
J., and N. N
outhwestern
D-27
d Auen, L.M.
airie ecosyst
ology 5:497-5
coherent fin
rown. 2003
the Rocky M
ions of incre
n in natural
Allen, Jr., G.
oxide, trace
Am. Soc. A
and Stephen
h and Game
d M. E. Biond
orthwest Co
al Distributio
Undisturbed S
rrow Charac
ho. America
1997. Plan
H. Shugart, a
ystem Prope
d.
dford. 201
d-latitude dr
ord. 2012b.
bility pattern
Gower. 2001
tional Labora
Y., Lu, J., Vec
aik. 2007. M
North Amer
Updated T
1999. Biom
tem after lon
506.
ngerprint of c
. Biology an
Mountains,
easing carbo
and manage
H. Heichel,
e gases, and
Agron., Crop
B. Monsen.
e. Publicatio
dini. 1984. V
lorado. Re
on of Soil R
Soils. Health
cteristics of
an Midland N
nt functional
and F. Wood
erties and G
2a. Conse
ry regions. G
Effects of
s, and mode
. Worldwide
atory. ORNL
cchi, G., Hua
Model project
rica. Science
Tailings Cov
mass produc
ng-term expo
climate chang
nd establishm
USA. Land
n dioxide an
ed ecosyste
C.W. Stube
d climate c
p Sci. Soc. A
. 1968. Res
on No. 68-3.
Vegetation e
eclamation a
Removed by
h Physics 54
Four Specie
Naturalist 118
types in tem
dward (eds.)
Global Chan
equences of
Global Chan
ecohydrolog
el accuracy
e Historical E
L/TM-2001/26
ang, H., Har
tions of an im
e 316:1181-1
er Design R
MWH America
Augus
ction and sp
osure to ele
ge impacts a
ment of mou
d Degradati
nd climate ch
ms. pp 83-1
er, D.E. Kiss
change on g
Am., and So
storing Big-G
Utah Divisi
establishmen
and Revege
Four Speci
:445–450.
es of Roden
8:245–260.
mperate sem
. Plant Func
nge. Camb
f declining
nge Biology.
gical variable
in big sageb
Estimates of
68.
rnik, N., Leet
mminent tran
184.
Report
as, Inc.
st 2012
pecies
vated
across
untain
on &
hange
10 In
el, S.
global
il Sci.
Game
ion of
nt and
tation
es of
nts in
mi-arid
ctional
bridge
snow
Doi:
es on
brush.
f Leaf
tmaa,
nsition

Denison M

Seager,
so
1
Sims, Ph
g
Spence,
F
Sydnor, R
to
1
Sykes, M
Jo
Thornbur
R
G
USDA. 2
U.S. Glob
U
P
Utah Dep
M
M
Verdolin,
of
a
Walther G
G
4
Wasser,
D
F
Waugh,
E
th
D
R
Waugh, W
2
ines Corp.
R. and G. V
outhwestern
07:21277-21
hillip and J.
rasslands. J
L. E. 1937.
orestry 35:7
Russell S. a
opsoil treatm
786.
M. T. 2009. C
ohn Wiley &
rg, Ashley A.
Regions. US
Government P
2009. http://p
bal Change
United States
Press.
partment of
Mines (USA)
March.
J., K. Lewis
f Gunnison’s
nd Utah (C.
G., E. Post,
Guldberg, and
16:389–395.
Clinton H.
Disturbed Lan
WS/OBS-82
W.J. 2010.
Evaluation of
he Workshop
Decommissio
Regulatory Co
W. J., M. K.
008. Monito
Vecchi. 201
North Am
1282.
S. Singh. 1
J. of Ecology
Root studi
747-754.
nd Edward
ents overlyin
Climate Cha
Sons, Ltd.
1982. Plan
SDA. Soil C
Printing Offic
plants.USDA
Research P
s. T. R. Karl
Environmen
Corp’s Whit
s and C. Slob
s (Cynomy gu
parvidens) P
P. Convey,
d F. Bairlein
.
1982. Eco
nds in the W
2/56. U.S. Go
. A Role fo
Earthen Co
p on Enginee
ning, and U
ommission, R
Kastens, L.
oring the pe
10. Greenh
merica. Pro
1978. The s
66:573-597.
es of import
F. Redente.
ng a phytotox
nge Impacts
nt Materials f
Conservation
ce. Washingt
A.gov. Acces
rogram (USG
l, J. M. Meli
tal Quality, D
te Mesa Rec
bodchidoff. 2
unnisoni), W
Prairie Dogs.
A, Menzel,
n. 2002. Ec
ology and C
West. U.S.
overnment P
or Natural A
vers for Ura
ered Barrier P
Uranium Mill
Rockville, Ma
R. L. Shead
rformance o
D-28
ouse warmin
oceedings o
structure and
.
tant range pl
2000. Lon
xic growth me
s: Vegetation
for Use on S
n Service.
ton, D.C.
ssed on July
GCRP). 200
illo, and T. C
Division of R
clamation Pl
2008. Morp
White-tailed (C
The Southw
C. Parmes
cological resp
Culture of S
Departmen
Printing Office
Analogs in th
nium Mill Ta
Performance
Tailings Fa
aryland.
er, C. H. Ben
of an alternat
Updated T
ng and the
of the Natio
d function of
lants of the
ng-term plan
edium. J. En
n. In Encyclo
Surface-Mine
SCS-TP-157
24, 2012.
09. Global Cl
C. Peterson
Radiation Co
lan, Rev. 5.0
hology of bu
C. leucurus),
western Natu
an, T. Beeb
ponses to re
Selected Spe
nt of Interior
e. Washingto
he Design a
ailings. pp. 7
e Related to L
acilities, NU
nson, W. H.
tive landfill c
Tailings Cov
21st century
onal Acade
f ten western
Boise River
nt community
nvironmenta
opedia of Life
ed Lands in A
7. EPA-600
limate Chang
(eds). Cam
ontrol (DRC)
0; Interrogat
urrow system
black-tailed
uralist 53:201
bee, J. From
ecent climate
ecies Useful
r. Fish and
on, D.C.
and Long-Te
7.18 - 7.23 I
Low-Level Ra
REG/CP-019
Albright, and
cover at the
er Design R
MWH America
Augus
y hydroclima
my of Scie
n North Ame
watershed.
y developme
l Quality 29:1
e Sciences (
Arid and Sem
0/7-79-134.
ge Impacts i
mbridge Univ
), 2012. De
tories – Rou
ms: A compa
(C. ludovicia
-207.
mentin, O. Ho
e change. N
l in Revege
Wildlife Se
erm Perform
In Proceedin
adioactive W
95, U.S. Nu
d P. S. Mush
Monticello,
Report
as, Inc.
st 2012
ate of
ences
erican
J. of
ent on
1778-
ELS).
miarid
U.S.
in the
versity
ension
und 1.
arison
anus),
oegh-
Nature
etating
ervice.
mance
ngs of
Waste,
uclear
hovic.
Utah,

Denison M

U
S
Waugh, W
u
A
U
Weaver,
Weaver,
N
Westerlin
8
Williams,
tr
C
Wilson, D
R
Wiscomb
S
Wyatt, J.
st
ines Corp.
Uranium Mill
Symposium.
W. J. and K
ranium mill t
Adjacent Reg
U.S. Departm
J. E. 1954.
J. E. and F.
NY.
ng, A. L. and
7(Suppleme
A., J. Micha
ree growth t
Century. Eart
D. and D. Re
Reference (3r
b, G. W. and
Service, Wildl
. W., D. J. D
tripmine spo
Tailings D
Phoenix, AZ
. Petersen.
tailings repos
gions: Impli
ment of Energ
North Ameri
. E. Clement
B. P. Bryant
nt 1): S231-S
aelsen, S. Lea
to climate c
th Interaction
eeder. 2005
rd Edition). J
T. A. Mess
ife Damage
Dollhopf, an
ils in southea
Disposal Site
Z.
1994. Pale
sitories. pp.
ications for
gy, Washingto
ican Prairie.
ts. 1938. P
t. 2008. Clim
S249.
avitt, and C.
hange in th
ns 14:1–20.
5. Mammal S
John Hopkins
mer. 2010.
Managemen
d W. M. Sc
astern Monta
D-29
e. Proceed
eoclimatic da
163-185 In
Environment
on, D.C.
Johnsen Pu
Plant Ecology
mate change
Still. 2010.
e continenta
Species of th
s University P
Pocket Gop
nt Series. ww
chafer. 1980
ana. J. Rang
Updated T
dings of the
ata applicatio
Climate Cha
tal Restorat
ublishing Com
y. 2nd Editio
and wildfire
Using tree ri
al United St
he World: A
Press. Baltim
phers. Utah
ww.Extension
0. Root dis
ge Managem
Tailings Cov
e Waste Ma
on: long-term
ange in the
ion and Lan
mpany. Linc
on. McGraw
in California.
ings to predic
tates during
At Taxonomic
more, MD.
h State Coop
n.USU.edu
stribution in
ment 33:101-1
er Design R
MWH America
Augus
anagement
m performan
Four corners
nd Use Plan
coln, NE.
w-Hill. New
. Climatic Ch
ct the respon
the Twenty
c and Geogr
perative Exte
1 to 48 yea
104.
Report
as, Inc.
st 2012
2008
nce of
s and
nning.
York,
hange
nse of
y-First
raphic
ension
ar old
MILL SITE
TAILINGS AND PROCESS
SOLUTIONS CELLS
1
2
3
4A4B
LOCATION OF 2012 PLANT
COVER SURVEY TRANSECTS FIGURE D.1
1009740 TRANS
WHITE MESA MILL RECLAMATION
AUG 2012
LEGEND
MILL SITE
TAILINGS AND PROCESS
SOLUTIONS CELLS
1
2
3
4A4B
LOCATION OF 2012 ANIMAL
COVER SURVEY TRANSECTS FIGURE D.2
1009740 TRANS
WHITE MESA MILL RECLAMATION
AUG 2012
LEGEND

ATTACHMENT H

SUPPORTING DOCUMENTATION FOR INTERROGATORY 12/1:

REVISED APPENDIX C, RADON EMANATION MODELING,
TO THE UPDATED TAILINGS COVER DESIGN REPORT
(APPENDIX D OF RECLAMATION PLAN, REVISION 5.0)

Updated Tailings Cover Design Report

APPENDIX C

RADON EMANATION MODELING

Denison Mines Corp. MWH Americas, Inc.
C-1 August 2012
C.1 BACKGROUND

This appendix presents the results of modeling the emanation of radon-222 from the top surface
of the proposed cover over the White Mesa tailing impoundments to achieve the State of Utah’s
long-term radon emanation standard for uranium mill tailings (Utah Administrative Code, Rule
313-24). These results comprise an update of radon emanation modeling presented in
Attachment F of the 2009 Reclamation Plan (Denison, 2009) and Appendix H of the Infiltration
and Contaminant Transport Modeling Report (Denison, 2010), as well as an update to Appendix
C of MWH (2011). This appendix provides a summary of further analyses of radon attenuation
through the proposed evapotranspiration (ET) cover, and incorporates the revised cover grading
design, and results of cover material testing conducted in 2010 and 2012.

The monolithic ET cover system evaluated in this appendix consists of the following layers from
top to bottom:

• 0.5 ft (15 cm) Erosion Protection Layer (gravel-admixture or topsoil)
• 3.5 ft (107 cm) Water Storage/Biointrusion/Frost Protection/Radon Attenuation Layer
(loam to sandy clay)
• 3.6 to 4.7 ft (110 to143 cm) Radon Attenuation Layer (highly compacted loam to
sandy clay)
• 2.5 ft (76 cm) Radon Attenuation and Grading Layer (loam to sandy clay)

The loam to sandy clay soil used to construct the ET cover, referred to in previous reports (Titan
1996, Knight Piesold 1999) as random/platform fill, is stockpiled at the site.
C.2 DESCRIPTION OF MODEL AND INPUT VALUES

The thickness of the reclamation cover necessary to limit radon emanation from the disposal
areas was analyzed using the NRC RADON model (NRC, 1989). The model utilizes the one-
dimensional radon diffusion equation, which uses the physical and radiological characteristics of
the tailings and overlying materials to calculate the rate of radon emanation from the tailings
through the cover. The model was used to calculate the cover thickness required to limit the
radon emanation rate through the top of the cover to 20 picocuries per square meter per second
(pCi/m2-s), following the guidance presented in U.S. Nuclear Regulatory Commission (NRC)
publications NUREG/CR-3533 and Regulatory Guide 3.64 (NRC 1984, 1989). The rate of
emanation standard is applied to the average emanation over the entire surface of the disposal
area.

The input parameters used in the model are based on engineering experience with similar
projects, recent laboratory testing results for samples of random fill, in addition to available data
from previous work by others, including Chen and Associates (1978, 1979, 1987), Rogers and
Associates Engineering Corporation (1988), Western Colorado Testing (1999a, 1999b), IUC
(2000), and Titan (1996). The available data from recent testing as well as previous testing
performed by others is summarized in Appendix A. The input parameters and values used in
the model are outlined below.

Denison Mines Corp. MWH Americas, Inc.
C-2 August 2012

C.2.1 Thickness of Tailings

The thickness of tailings currently deposited in Cells 2 & 3 is approximately 30 ft (914 cm), while
the anticipated tailings thickness deposited in Cells 4A & 4B will be approximately 42 ft (1,280
cm). As documented in NRC Regulatory Guide 3.64, a tailings thickness greater than 100 to
200 cm is effectively equivalent to an infinitely thick radon source. Therefore, a thickness of 500
cm may be used in RADON to represent an equivalent infinitely thick tailings source of radon.

C.2.2 Radium Activity Concentration

The radium-226 activity concentration values for the tailings in the impoundments are estimated
based on material inventory data provided by Denison. A summary of the material inventories
for Cells 2 and 3 and the projected inventory for Cells 4A and 4B is provided in Attachment C.1.
The radium-226 and thorium-230 activity concentrations are listed for each material in the
inventories. These values were used to calculate a weighted average for radium-226 and
thorium-230 activity concentrations for the tailings using the volume of material placed in Cells 2
and 3. In addition, these values were used to project radium-226 and thorium-230 activity
concentrations for the materials to be placed in Cells 4A and 4B. Calculations for radium-226
from decay of thorium-230 were also made. These calculations are also provided in Attachment
C.1. The results for Cell 3 and Cells 4A and 4B indicate the highest radium-226 values are a
result of original radium-226 and radium-226 from thorium-230 decay at approximately 1000
years. The results are summarized below and in Table C.1.

Table C.1. Radium Activity Concentrations
Tailings Cell
Weighted
Average
Radium-226
Activity
Concentration
(pCi/g)
Weighted
Average
Thorium-230
Activity
Concentration
(pCi/g)
Total Radium-226 Activity
Concentration (original
radium-226 and radium-
226 from thorium-230
decay)
(pCi/g)
Cell 2 923 923 923
Cell 3 606 1048 758
Cells 4A and 4B 617 695 642

Random Fill and Erosion Protection. The radium activity of the random fill and erosion
protection layer is assumed to be zero, based on guidance in Regulatory Guide 3.64 (NRC,
1989) which states that radium activity in the cover soils may be neglected for cover design
purposes provided the cover soils are obtained from background materials that are not
associated with ore formations or other radium-enriched materials.

C.2.3 Radon Emanation Coefficient

The radon emanation coefficient used in the model for the tailings is 0.20 based on laboratory
data (Rogers & Associates, 1988) and the recommendation in NUREG-1620 (NRC, 2003) to
use a value of 0.20 for tailings if there is limited, site-specific data.

The radon emanation coefficient used in the model for the cover layers is 0.35. This is the
conservative default value used in the RADON model.

Denison Mines Corp. MWH Americas, Inc.
C-3 August 2012

C.2.4 Specific Gravity, Density and Porosity

The densities and porosities of the tailings and cover materials used in the model are based on
laboratory testing results. The values are summarized in Table C.2 and discussed in more
detail below.

Table C.2. Density and Porosity Values
Material Specific
Gravity
Degree of
Compaction
(%)
Placed
Density
(pcf)
Placed
Density
(g/cc)
Porosity
Erosion Protection* 2.62 85% SP 106 1.7 0.35
Random fill (low compaction
water storage, rooting zone) 2.63 85% SP 100 1.6 0.39
Random Fill (high compaction) 2.63 95% SP 112 1.8 0.32
Random Fill (in place, low
compaction, platform fill) 2.63 80% SP 94 1.5 0.43
Tailings 2.75 --- 90 1.4 0.47
SP = standard proctor compaction
* Estimated by applying a 25% rock correction

The specific gravity of the tailings was estimated as 2.75, and the dry density of the tailings was
estimated as 90 pcf, based on laboratory tests (Chen and Associates, 1987 and Western
Colorado Testing, 1999b) and assuming the long-term density of the tailings is at 85 percent of
the average laboratory measured maximum dry density. The referenced reports are provided
as part of Appendix A.1. The porosity of the tailings was calculated using the estimated specific
gravity and dry density based on the following equation:

(Eq. C.1)
where
n = porosity,
γd = dry density of soil,
Gs = specific gravity of soil, and
γw = unit weight of water.

The specific gravity and dry density values used in the model for the random fill layers were
estimated by laboratory tests (ATT, 2010 and UWM, 2011). The referenced reports are
provided as part of Appendix A.2. The estimation for the values used in the model is provided in
Attachment C.2. The porosity values for the layers were calculated using equation C.1. The
proposed cover system has three layers of random fill placed at different levels of compaction.
The lower layer of random fill consists of a minimum thickness of 2.5 feet of random fill that is
assumed to be dumped and minimally compacted by construction equipment to approximately
80 percent standard Proctor. The middle layer (2.5 feet) of random fill will be compacted to 95
percent of standard Proctor. In Cell 2 and parts of Cell 3, the lower layer of random fill is
already placed and is approximately 3 feet. It is assumed the upper 6 inches of this fill will be
part of the middle random fill layer and can be compacted by additional passes of compactors to
reach 95 percent of standard Proctor compaction. The uppermost 3.5 feet of random fill will be
placed at 85 percent of standard Proctor compaction in order to optimize water storage and
rooting characteristics for plant growth.

Denison Mines Corp. MWH Americas, Inc.
C-4 August 2012
The 0.5 foot erosion protection layer is assumed to be rock mulch consisting of topsoil material
mixed with 25 percent gravel by weight. The specific gravity and density of the erosion
protection layer was estimated to be 2.62 and 106 pcf, respectively, based on laboratory testing
results for random fill (ATT, 2010 and UWM, 2011) and applying a rock correction based on
25% gravel by weight.

C.2.5 Long-term Moisture Content

The long-term moisture content value for the tailings is assumed to be 6 percent. This is a
conservative assumption, per NRC Regulatory Guide 3.64 (NRC, 1989), which represents the
lower bound for moisture in western soils and is typically used as a default value for the long-
term water content of tailings.

MWH collected representative samples from the on-site random fill and topsoil stockpiles for
use in estimating the long-term moisture contents for the random fill and erosion protection
cover layers. The laboratory results for the 15 bar water contents for these samples were used
to estimate long-term water contents for the random fill and erosion protection layers.

The long-term water content of the topsoil was estimated as 5.2 percent based on the measured
15 bar gravimetric water content for a topsoil sample (E1-A) which represents the average index
properties for the topsoil stockpiles. The long-term water content of the rock mulch was
estimated as 4 percent based on the addition of 25 percent gravel by weight to the topsoil.

Based on the cover material gradations, the cover soils were bracketed into three groups, finer
grained soils, uniform graded soils, and broadly graded soils. A weighted average procedure
that accounts for the size of soil type based on the stockpile volumes was incorporated to
determine the average long-term gravimetric water content for the random fill using the
measured 15 bar water contents. The estimation of the long-term water content value for the
cover material is provided in Attachment C.2.

The average long-term moisture contents are summarized in Table C.3.

Table C.3. Estimated Long-Term Moisture Contents
Material
Gravimetric
Water
Content (%)
Erosion Protection (rock mulch) 4.0
Erosion Protection (topsoil) 5.2
Random fill 6.7
Tailings 6.0

C.2.6 Diffusion Coefficient

The radon diffusion coefficient used in the RADON model can either be calculated within the
model (based on an empirical relationship dependent upon porosity and the degree of
saturation) or input directly in the model using values measured from laboratory testing.
Although laboratory test data was available for the tailings and the cover material (Rogers &
Associates 1988), tests were performed at porosities and water contents different than those

Denison Mines Corp. MWH Americas, Inc.
C-5 August 2012
estimated to represent long-term conditions. Therefore, the empirical relationship in RADON
was used, resulting in the calculated values summarized in Table C.4 below.

Table C.4. Calculated Radon Diffusion Coefficients
Material Diffusion
Coefficient (cm2/s)
Erosion Protection (rock mulch) 0.0354
Erosion Protection (topsoil) 0.0330
Random Fill (low compaction water
storage, rooting zone) 0.0274
Random Fill (high compaction) 0.0176
Random Fill (in place, low
compaction, platform fill) 0.0326
Tailings 0.0401

C.3 MODEL RESULTS

The radon emanation modeling results show that the designed cover systems presented in
Table C.5 will reduce the rate of radon emanation to values below the limit of 20 picocuries per
square meter per second (pCi/m2-s) averaged over the entire area of the tailings impoundments,
which is the regulatory criterion (Utah Administrative Code, Rule 313-24). The RADON model
output is provided in Attachment C.3.

Table C.5. Summary of Results
Cover Layer Cover Thickness (ft)
Cell 2 Cell 3 Cells 4A/4B
Erosion Protection (rock mulch or
topsoil) 0.5 0.5 0.5
Random Fill (low compaction water
storage, rooting zone) 3.5 3.5 3.5
Random Fill (high compaction) 4.7 4.0 3.6
Random Fill (in place, low
compaction, platform fill) 2.5 2.5 2.5
Total Cover Thickness 11.2 10.5 10.1

C.4 IMPACTS OF INCREASED THICKNESS OF RANDOM FILL

Radon modeling as discussed above assumed that the lower layer of random fill was placed at
80 percent of standard Proctor compaction, and had a thickness of 2.5 feet (assuming top 6
inches can be compacted to 95% standard Proctor compaction prior to placement of additional
fill). However, based on the assumption that the top of tailings is 18 inches below the top of the
flexible membrane liner (FML), the thickness of existing random fill in Cell 2 is significantly
thicker than 3.0 feet in some areas. Additional modeling was performed to determine the
minimum thickness of highly compacted random fill required in order to meet regulatory criterion
to limit the radon emanation rate through the top of the cover to 20 pCi/m2-s. This modeling
indicates that for every extra foot of low-compaction random fill (80% standard Proctor
compaction), the highly compacted random fill layer (95% standard Proctor compaction) can be
reduced in thickness by 0.70 ft. This trend is shown in Figure C.1. The RADON model output is
provided in Attachment C.4.

Denison Mines Corp. MWH Americas, Inc.
C-6 August 2012

C.5 REFERENCES

Advanced Terra Testing (ATT), 2010. Denison White Mesa Project, Job No. 2521-53,
Laboratory Testing for Borrow Stockpiles. October.

Chen and Associates, Inc., 1978. Earth Lined Tailings Cells, White Mesa Uranium Project,
Blanding, Utah, Report prepared for Energy Fuels Nuclear, Inc., July 18.

Chen and Associates, Inc., 1979. Soil Property Study, Proposed Tailings Retention Cells, White
Mesa Uranium Project, Blanding, Utah, Report prepared for Energy Fuels Nuclear, Inc.
January 23.

Chen and Associates, Inc., 1987. Physical Soil Data, White Mesa Project, Blanding Utah,
Report prepared for Energy Fuels Nuclear, Inc.

Denison Mines USA Corporation (Denison), 2009. Reclamation Plan, White Mesa Mill,
Blanding Utah, Revision 4.0, November.

Denison Mines USA Corporation (Denison), 2010. Revised Infiltration and Contaminant
Transport Modeling Report, White Mesa Mill, Blanding, Utah, March.

Geosyntec Consultants (Geosyntec), 2006. Stockpile Evaluation Tailings Cell 4A, White Mesa
Mill - Technical Memo prepared for International Uranium (USA) Corporation. January
23.

International Uranium Corporation (IUC), 2000. Reclamation Plan, White Mesa Mill, Blanding,
Utah, Source Material License No. SUA-1358, Docket No. 40-8681, Revision 3.0. July.

Knight Piesold, 1999. Radon Emanation Calculations (Revised). Technical Memorandum from
Roman Popielak and Pete Duryea to File 1626B. April 15.

MWH Americas, Inc. (MWH), 2011. Updated Tailings Cover Design. Prepared for Denison
Mines (USA) Corp. September.

Rawls, W.J., and Brakensiek, D.L., 1982. Estimating Soil Water Retention from Soil Properties,
Journal of the Irrigation and Drainage Division, American Society of Civil Engineers, Vol
108, No. IR2, 166-171. June.

Rogers & Associates Engineering Corporation, 1988. Two separate letters prepared by Renee
Y. Bowser for C.O. Sealy of Umetco Minerals Corporation. March 4 and May 9.

TITAN Environmental Corporation (Titan), 1996. Tailings Cover Design, White Mesa Mill,
Blanding Utah, Report prepared for Energy Fuels Nuclear, Inc. September.

University of Wisconsin-Madison (UWM), Wisconsin Geotechnics Laboratory, 2012.
Compaction and Hydraulic Properties of Soils from Banding, Utah. Geotechnics Report
NO. 12-41 by C.H. Benson and X. Wang. July 24.

Denison Mines Corp. MWH Americas, Inc.
C-7 August 2012
U.S. Nuclear Regulatory Commission (NRC), 1984. Radon Attenuation Handbook for Uranium
Mill Tailings Cover Design, NUREG/CR-3533.
U.S. Nuclear Regulatory Commission (NRC), 1989. Calculation of Radon Flux Attenuation by
Earthen Uranium Mill Tailings Covers, Regulatory Guide 3.64.
Western Colorado Testing, Inc., 1999a. Soil Sample Testing Results for On-Site Random Fill
and Clay Stockpiles, prepared for International Uranium (USA) Corporation. May.

Western Colorado Testing, Inc., 1999b. Report of Soil Sample Testing of Tailings Collected
from Cell 2 and Cell 3, Prepared for International Uranium (USA) Corporation. May 4.

PROJECT
RADON EMANATION 
INCREASED THICKNESS OF LOWER RANDOM FILL 
VS TOTAL COVER THICKNESS
TITLE
DATE
FILENAME
FIGURE C.1 
White Mesa Mill Reclamation
AUG 2012
Summary of Radon Runs_8‐7‐2012pptxDenison Mines (USA) Corp
y = 0.3257x + 10.319
y = ‐0.6743x + 6.3167
0.0
2.0
4.0
6.0
8.0
10.0
12.0
14.0
16.0
0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0
Re
q
u
i
r
e
d
 Th
i
c
k
n
e
s
s
 (f
t
)
Thickness of Lower Random Fill (ft)
Total cover thickness
Highly Compacted Random Fill Layer
(compacted to 95% standard Proctor
compaction)

ATTACHMENT C.1
RADIUM-226 ESTIMATION TABLES
Denison Mines (USA) Corp.
White Mesa Mill Site, Summary of Processed Ores and Alternate Feeds
Material
Category/Location Origin/ Description Dates
Total Mass
Ores
Processed
(tons) %U3O8
Ra-226
Activity
Conc.a
(pCi/g)
Th-230
Activity
Conc.b
(pCi/g) Reference/Comments
Processed Ores
Natural Ores Arizona Strip Ores 1980 - 2000 1,000,000 0.55 1546.6 1546.6 Total quantity for both ores from Denison (2009, 2011), ore grades and quantity breakdown from Roberts (2012b)
Colorado Plateau Ores 1980 - 2000 2,840,536 0.25 703.0 703.0 Total quantity for both ores from Denison (2009, 2011), ore grades and quantity breakdown from Roberts (2012b)
Pandora 2008-2011 231,191 0.218 613.0 613.0 Data provided from D. Turk (2012a)
Daneros 2010-2011 71,287 0.269 756.4 756.4 Data provided from D. Turk (2012a)
Beaver 2010-2011 90,280 0.174 489.3 489.3 Data provided from D. Turk (2012a)
Arizona 1 2010-2011 41,863 0.608 1709.7 1709.7 Data provided from D. Turk (2012a)
Sunday 2008-2011 20,251 0.178 500.5 500.5 Data provided from D. Turk (2012a)
West Sunday 2008-2010 79,744 0.157 441.5 441.5 Data provided from D. Turk (2012a)
Topaz 2008-2010 16,869 0.128 359.9 359.9 Data provided from D. Turk (2012a)
St. Jude 2008-2010 29,572 0.167 469.6 469.6 Data provided from D. Turk (2012a)
Tony M 2008-2009 189,876 0.131 368.4 368.4 Data provided from D. Turk (2012a)
Dawn Mining 2009-2010 2,875 0.456 1282.3 1282.3 Data provided from D. Turk (2012a)
Carnation 2009-2010 5,584 0.166 466.8 466.8 Data provided from D. Turk (2012a)
Purchased Ore 2010-2011 18,008 0.146 410.6 410.6 Data provided from D. Turk (2012a)
Humbug Cressler 2011 118 0.044 123.7 123.7 Data provided from D. Turk (2012a)
Alternate Feeds
Linde Soil 1996-1999, 2002-2003, 2007 258,992 33 133 Date range est. from Denison (2011) and Roberts (2012c). Quantities est. from Roberts (2012a,2012c). Activities est. from Turk (2012b).
Ashland 1 Soil 1996-1999, 2002-2003 317,831 91.3 1849 Date range est. from Denison (2011) and Roberts (2012c). Quantities and activities est. from Roberts (2012a,2012c).
Heritage Monazite sands 1996-1999, 2002-2003, 2007 7,374 19.4 10.6 Date range est. from Denison (2011) and Roberts (2012c). Quantities est. from Roberts (2012a,2012c). Activities est. from Turk (2012b).
Cabot Tantalum residues 1996-1999 16,828 772 118 Date range est. from Denison (2011) and Roberts (2012c). Quantities est. from Roberts (2012a,2012c). Activities est. from Turk (2012b).
Ashland 2 Soil 1996-1999 43,981 91.3 1849 Date range est. from Denison (2011) and Roberts (2012c). Quantities and activities est. from Roberts (2012a,2012c).
Cameco KF product 1996-1999 1,966 0.6 5.3 Date range est. from Denison (2011) and Roberts (2012c). Quantities est. from Roberts (2012a,2012c). Activities est. from Turk (2012b).
Allied Signal/Honeywell Calcium Fluoride 1996-1997 2,343 989 23800 Date range est. from Denison (2011) and Roberts (2012c). Quantities est. from Roberts (2012a,2012c). Activities est. from Turk (2012b).
Cameco Phosph. regen. product 1996-1999 557 2.70 2.10 Date range est. from Denison (2011) and Roberts (2012c). Quantities est. from Roberts (2012a,2012c). Activities est. from Turk (2012b).
Cameco Calcined product 1996-1999 2,197 1040 9170 Date range est. from Denison (2011) and Roberts (2012c). Quantities est. from Roberts (2012a,2012c). Activities est. from Turk (2012b).
Allied Signal KOH solution recovery 1996-1999 1,526 989 0.00 Date range est. from Denison (2011) and Roberts (2012c). Quantities est. from Roberts (2012a,2012c). Activities est. from Harold (2012a) and Turk (2012b).
Rhone-Poulenc Uranyl nitrate hexahydrate 1996-1997 17 156 2550 Date range est. from Denison (2011) and Roberts (2012c). Quantities est. from Roberts (2012a,2012c). Activities est. from Harold (2012a) and Turk (2012b).
Cameco UF4 with filter ash 1996-1999 10 156 2550 Date range est. from Denison (2011) and Roberts (2012c). Quantities est. from Roberts (2012a,2012c). Activities est. from Turk (2012b).
Nev. Test Site Cotter Concentrate 1996-1997 420 3590 585000 Date range est. from Denison (2011) and Roberts (2012c). Quantities and activities est. from Roberts (2012a,2012c).
Molycorp 2002-2003, 2007 11,689 38.6 268.0 Date range est. from Denison (2011) and Roberts (2012c). Quantities est. from Roberts (2012a,2012c). Activities est. from Turk (2012b).
Cabot Tantalum residues 2011 8,700 772 118 Date range est. from Denison (2011) and Roberts (2012c). Quantities est. from Roberts (2012a,2012c). Activities est. from Turk (2012b).
Cameco UF4 2009-2010 462 156 2550 Date range est. from Denison (2011) and Roberts (2012c). Quantities est. from Roberts (2012a,2012c). Activities est. from Turk (2012b).
Allied Signal/Honeywell Calcium Fluoride 2011 1,969 989 23800 Date range est. from Denison (2011) and Roberts (2012c). Quantities est. from Roberts (2012a,2012c). Activities est. from Turk (2012b).
FMRI (Fansteel)2011 1,369 236 4.9 Date range est. from Denison (2011) and Roberts (2012c). Quantities est. from Roberts (2012a,2012c). Activities est. from Turk (2012b).
Notes:
aValues for ores estimated using method in NRC Reg. Guide 3.64 (1989) of multiplying the ore grade by 2812 pCi/g.
bValues for thorium estimated as Ra-226 values.
References:
Denison Mines USA Corporation (Denison), 2009. Reclamation Plan, White Mesa Mill, Blanding Utah, Revision 4.0, November.
Denison Mines USA Corporation (Denison), 2011. Reclamation Plan, White Mesa Mill, Blanding Utah, Revision 5.0, September.
Roberts, H., 2012a. Electronic communication including files "InvThNov00.xls and Inventory Umass in tails.xls" from Harold Roberts, Denison Mines (USA) Corp., to Melanie Davis, MWH Americas, Inc., July 20.
Roberts, H., 2012b. Personal communication from Harold Roberts, Denison Mines (USA) Corp., to Melanie Davis, MWH Americas, Inc., June 21.
Roberts, H., 2012c. Electronic communication including file "Alternate Feed Tons.pdf" and personal communication from Harold Roberts, Denison Mines (USA) Corp., to Melanie Davis, MWH Americas, Inc., July 24.
Turk, D., 2012a. Electronic communication including file "Ore Numbers.pdf" from David Turk, Denison Mines (USA) Corp., to Melanie Davis, MWH Americas, Inc., June 8.
Turk, D., 2012b. Electronic communication including file "DAC s Calculations 2012_rev6-29-12" from David Turk, Denison Mines (USA) Corp., to Melanie Davis, MWH Americas, Inc., June 29.
Impoundment Inventory Summary_7Aug2012_MWH:Inventory
Denison Mines (USA) Corp.
Estimation of Cell 2 Ra-226 and Th-230 Activity Concentrations for Tailings
Material
Category/Location Origin/ Description Dates
Total Mass
Ores
Processed
(tons)
Total Mass
Ore
Processed
for Cell 2a
(tons)%U3O8
Ra-226
Activity
Conc.b
(pCi/g)
Th-230
Activity
Conc.c
(pCi/g) Reference/Comments
Processed Ores
Arizona Strip Ores 1980 - 2000 1,000,000 598,875 0.55 1547 1547 Total quantity for both ores from Denison (2009, 2011), ore grades and quantity breakdown from Roberts (2012b)
Colorado Plateau Ores 1980 - 2000 2,840,536 1,701,125 0.25 703 703 Total quantity for both ores from Denison (2009, 2011), ore grades and quantity breakdown from Roberts (2012b)
Total Tons 2,300,000 Weighted Ave.923 923
Notes:cEstimated from total tons of tailings to Cell 2 from Denison (2009), Attachment E. Estimated mass is for ore processed. Material placed in Cell 2 are only those listed in the table (Roberts, 2012c).
bValues for ores estimated using method in NRC Reg. Guide 3.64 (1989) of multiplying the ore grade by 2812 pCi/g.
cValues for thorium estimated as Ra-226 values.
References:
Denison Mines USA Corporation (Denison), 2009. Reclamation Plan, White Mesa Mill, Blanding Utah, Revision 4.0, November.
Denison Mines USA Corporation (Denison), 2011. Reclamation Plan, White Mesa Mill, Blanding Utah, Revision 5.0, September.
Roberts, H., 2012b. Personal communication from Harold Roberts, Denison Mines (USA) Corp., to Melanie Davis, MWH Americas, Inc., June 21.
Roberts, H., 2012c. Electronic communication including file "Alternate Feed Tons.pdf" and personal communication from Harold Roberts, Denison Mines (USA) Corp., to Melanie Davis, MWH Americas, Inc., July 24.
Natural Ores
Impoundment Inventory Summary_7Aug2012_MWH:Cell 2
Denison Mines (USA) Corp.
Estimation of Cell 3 Ra-226 and Th-230 Activity Concentrations for Tailings
Material
Category/Location Origin/ Description Dates
Total Mass
Ores
Processed
(tons)
Total Mass
Ore
Processed
for Cell 3a
(tons)%U3O8
Ra-226
Activity
Conc.a
(pCi/g)
Th-230
Activity
Conc.b
(pCi/g) Reference/Comments
Processed Ores
Natural Ores Arizona Strip Ores 1980 - 2000 1,000,000 401,125 0.55 1546.6 253.15 1546.6 253.15 Total quantity for both ores from Denison (2009, 2011), ore grades and quantity breakdown from Roberts (2012b)
Colorado Plateau Ores 1980 - 2000 2,840,536 1,139,411 0.25 703.0 326.85 703.0 326.85 Total quantity for both ores from Denison (2009, 2011), ore grades and quantity breakdown from Roberts (2012b)
Pandora 2008 80,046 80,046 0.218 613.0 20.02 613.02 20.02 Data provided from D. Turk (2012a)
Sunday 2008 12,066 12,066 0.178 500.5 2.46 500.54 2.46 Data provided from D. Turk (2012a)
West Sunday 2008 53,613 53,613 0.157 441.5 9.66 441.48 9.66 Data provided from D. Turk (2012a)
Topaz 2008 8,746 8,746 0.128 359.9 1.28 359.94 1.28 Data provided from D. Turk (2012a)
St. Jude 2008 15,140 15,140 0.167 469.6 2.90 469.60 2.90 Data provided from D. Turk (2012a)
Tony M 2008 74,802 74,802 0.131 368.4 11.24 368.37 11.24 Data provided from D. Turk (2012a)
Alternate Feeds
Linde Soil 1996-1999, 2002-2003, 2007 258,992 258,992 33 3.49 133 14.06 Date range est. from Denison (2011) and Roberts (2012c). Quantities est. from Roberts (2012a,2012c). Activities est. from Turk (2012b).
Ashland 1 Soil 1996-1999, 2002-2003 317,831 317,831 91.3 11.84 1849 239.80 Date range est. from Denison (2011) and Roberts (2012c). Quantities and activities est. from Roberts (2012a,2012c).
Heritage Monazite sands 1996-1999, 2002-2003, 2007 7,374 7,374 19.4 0.06 10.6 0.03 Date range est. from Denison (2011) and Roberts (2012c). Quantities est. from Roberts (2012a,2012c). Activities est. from Turk (2012b).
Cabot Tantalum residues 1996-1999 16,828 16,828 772 5.30 118 0.81 Date range est. from Denison (2011) and Roberts (2012c). Quantities est. from Roberts (2012a,2012c). Activities est. from Turk (2012b).
Ashland 2 Soil 1996-1999 43,981 43,981 91.3 1.64 1849 33.18 Date range est. from Denison (2011) and Roberts (2012c). Quantities and activities est. from Roberts (2012a,2012c).
Cameco KF product 1996-1999 1,966 1,966 0.6 0.00 5.3 0.00 Date range est. from Denison (2011) and Roberts (2012c). Quantities est. from Roberts (2012a,2012c). Activities est. from Turk (2012b).
Allied Signal/Honeywell Calcium Fluoride 1996-1997 2,343 2,343 989 0.95 23800 22.75 Date range est. from Denison (2011) and Roberts (2012c). Quantities est. from Roberts (2012a,2012c). Activities est. from Turk (2012b).
Cameco Phosph. regen. product 1996-1999 557 557 2.70 0.00 2.10 0.00 Date range est. from Denison (2011) and Roberts (2012c). Quantities est. from Roberts (2012a,2012c). Activities est. from Turk (2012b).
Cameco Calcined product 1996-1999 2,197 2,197 1040 0.93 9170 8.22 Date range est. from Denison (2011) and Roberts (2012c). Quantities est. from Roberts (2012a,2012c). Activities est. from Turk (2012b).
Allied Signal KOH solution recovery 1996-1999 1,526 1,526 989 0.62 0.00 0.00 Date range est. from Denison (2011) and Roberts (2012c). Quantities est. from Roberts (2012a,2012c). Activities est. from Harold (2012a) and Turk (2012b).
Rhone-Poulenc Uranyl nitrate hexahydrate 1996-1997 17 17 156 0.00 2550 0.02 Date range est. from Denison (2011) and Roberts (2012c). Quantities est. from Roberts (2012a,2012c). Activities est. from Harold (2012a) and Turk (2012b).
Cameco UF4 with filter ash 1996-1999 10 10 156 0.00 2550 0.01 Date range est. from Denison (2011) and Roberts (2012c). Quantities est. from Roberts (2012a,2012c). Activities est. from Turk (2012b).
Nev. Test Site Cotter Concentrate 1996-1997 420 420 3590 0.62 585000 100.26 Date range est. from Denison (2011) and Roberts (2012c). Quantities and activities est. from Roberts (2012a,2012c).
Molycorp 2002-2003, 2007 11,689 11,689 38.6 0.18 268.0 1.28 Date range est. from Denison (2011) and Roberts (2012c). Quantities est. from Roberts (2012a,2012c). Activities est. from Turk (2012b).
Total Tons 2,450,679 Weighted Ave.606 1048
Notes:
cEstimated from total tons of tailings to Cell 2 and capacity of Cell 3 from Denison (2009), Attachment E. Material placed before 2009 was placed in Cells 2 and 3 (Roberts, 2012c).
bValues for ores estimated using method in NRC Reg. Guide 3.64 (1989) of multiplying the ore grade by 2812 pCi/g.
cValues for thorium estimated as Ra-226 values.
References:
Denison Mines USA Corporation (Denison), 2009. Reclamation Plan, White Mesa Mill, Blanding Utah, Revision 4.0, November.
Denison Mines USA Corporation (Denison), 2011. Reclamation Plan, White Mesa Mill, Blanding Utah, Revision 5.0, September.
Roberts, H., 2012a. Electronic communication including files "InvThNov00.xls and Inventory Umass in tails.xls" from Harold Roberts, Denison Mines (USA) Corp., to Melanie Davis, MWH Americas, Inc., July 20.
Roberts, H., 2012b. Personal communication from Harold Roberts, Denison Mines (USA) Corp., to Melanie Davis, MWH Americas, Inc., June 21.
Roberts, H., 2012c. Electronic communication including file "Alternate Feed Tons.pdf" and personal communication from Harold Roberts, Denison Mines (USA) Corp., to Melanie Davis, MWH Americas, Inc., July 24.
Turk, D., 2012a. Electronic communication including file "Ore Numbers.pdf" from David Turk, Denison Mines (USA) Corp., to Melanie Davis, MWH Americas, Inc., June 8.
Turk, D., 2012b. Electronic communication including file "DAC s Calculations 2012_rev6-29-12" from David Turk, Denison Mines (USA) Corp., to Melanie Davis, MWH Americas, Inc., June 29.
Impoundment Inventory Summary_7Aug2012_MWH:Cell 3
Denison Mines (USA) Corp.
Estimation of Cell 4A and 4B Ra-226 and Th-230 Activity Concentrations for Tailings
Material
Category/Location Origin/ Description Dates
Total Mass
Ore/Alt. Feed
Processeda
(tons)%U3O8
Ra-226
Activity
Conc.b
(pCi/g)
Th-230
Activity
Conc.c
(pCi/g) Reference/Comments
Processed Ores
Pandora 2009-2011 151,145 0.218 613.0 613.0 Data provided from D. Turk (2012a)
Daneros 2010-2011 71,287 0.269 756.4 756.4 Data provided from D. Turk (2012a)
Beaver 2010-2011 90,280 0.174 489.3 489.3 Data provided from D. Turk (2012a)
Arizona 1 2010-2011 41,863 0.608 1709.7 1709.7 Data provided from D. Turk (2012a)
Sunday 2009-2011 8,185 0.178 500.5 500.5 Data provided from D. Turk (2012a)
West Sunday 2009-2010 26,131 0.157 441.5 441.5 Data provided from D. Turk (2012a)
Topaz 2009-2010 8,123 0.128 359.9 359.9 Data provided from D. Turk (2012a)
St. Jude 2009-2010 14,432 0.167 469.6 469.6 Data provided from D. Turk (2012a)
Tony M 2009 115,074 0.131 368.4 368.4 Data provided from D. Turk (2012a)
Dawn Mining 2009-2010 2,875 0.456 1282.3 1282.3 Data provided from D. Turk (2012a)
Carnation 2009-2010 5,584 0.166 466.8 466.8 Data provided from D. Turk (2012a)
Purchased Ore 2010-2011 18,008 0.146 410.6 410.6 Data provided from D. Turk (2012a)
Humbug Cressler 2011 118 0.044 123.7 123.7 Data provided from D. Turk (2012a)
Alternate Feeds
Cabot Tantalum residues 2011 8,700 772 118 Date range est. from Denison (2011) and Roberts (2012c). Quantities est. from Roberts (2012a,2012c). Activities est. from Turk (2012b).
Cameco UF4 2009-2010 462 156 2550 Date range est. from Denison (2011) and Roberts (2012c). Quantities est. from Roberts (2012a,2012c). Activities est. from Turk (2012b).
Allied Signal/Honeywell Calcium Fluoride 2011 1,969 989 23800 Date range est. from Denison (2011) and Roberts (2012c). Quantities est. from Roberts (2012a,2012c). Activities est. from Turk (2012b).
FMRI (Fansteel)2011 1,369 236 4.9 Date range est. from Denison (2011) and Roberts (2012c). Quantities est. from Roberts (2012a,2012c). Activities est. from Turk (2012b).
Weighted Ave. 617 695
Notes:
cCurrent tailings in Cell 4A and future tailings to Cell 4A and 4B are projected to be from ores and alternative feeds similar to those processed after 2008 (Roberts, 2012c).
bValues for ores estimated using method in NRC Reg. Guide 3.64 (1989) of multiplying the ore grade by 2812 pCi/g.
cValues for thorium estimated as Ra-226 values.
References:
Denison Mines USA Corporation (Denison), 2009. Reclamation Plan, White Mesa Mill, Blanding Utah, Revision 4.0, November.
Denison Mines USA Corporation (Denison), 2011. Reclamation Plan, White Mesa Mill, Blanding Utah, Revision 5.0, September.
Roberts, H., 2012a. Electronic communication including files "InvThNov00.xls and Inventory Umass in tails.xls" from Harold Roberts, Denison Mines (USA) Corp., to Melanie Davis, MWH Americas, Inc., July 20.
Roberts, H., 2012b. Personal communication from Harold Roberts, Denison Mines (USA) Corp., to Melanie Davis, MWH Americas, Inc., June 21.
Roberts, H., 2012c. Electronic communication including file "Alternate Feed Tons.pdf" and personal communication from Harold Roberts, Denison Mines (USA) Corp., to Melanie Davis, MWH Americas, Inc., July 24.
Turk, D., 2012a. Electronic communication including file "Ore Numbers.pdf" from David Turk, Denison Mines (USA) Corp., to Melanie Davis, MWH Americas, Inc., June 8.
Turk, D., 2012b. Electronic communication including file "DAC s Calculations 2012_rev6-29-12" from David Turk, Denison Mines (USA) Corp., to Melanie Davis, MWH Americas, Inc., June 29.
Impoundment Inventory Summary_7Aug2012_MWH:Cells 4A-B
Denison Mines (USA) Corp. White Mesa Mill
Tailings Cell 2
Calculation of Ra-226 Concentrations Due to Future Decay of Th-230
The RA-226 concentration at various times in the future depends on both the decay of the Ra-226 currently
present and the ingrowth from Th-230. The Ra-226 decays with a half-life of 1602 years. The ingrowth is also
a function of the Ra-226 half-life (1602 years) and the Th-230 half-life (77,000 years).
A (Ra-226) at a time t (years) = [A (Ra-226) at t=0][exp(-0.693t/1602 years)]
A (Ra-226 from decay of Th-230 at time t (years)) = [A (Th-230)][1-exp(-0.693t/1602 years)][exp(-0.693t/77,000 years)]
Residual Ra-226 at time t
Time exp (-0.693t/1602) Initial Ra-226 Concentration (pCi/g) Ra-226 Concentration at time t (pCi/g)
(years) Cell 2 Cell 2
0 1.000 923 923
100 0.958 923 884
200 0.917 923 847
500 0.805 923 743
1000 0.649 923 599
Ra-226 Concentration from Ingrowth Due to Decay of Th-230
Time exp (-0.693t/1602) Initial Th-230 Concentration (pCi/g) Ra-226 Concentration at time t (pCi/g) exp (-0.693t/77000)
(years) S.I.S.I.
0 1.000 923 0 1.000
100 0.958 923 39 0.999
200 0.917 923 76 0.998
500 0.805 923 179 0.996
1000 0.649 923 321 0.991
Total Ra-226 Concentration at Time t (original Ra-226 and Ra-226 from Th-230 decay)
Time Total Ra-226 Concentration (pCi/g)
(years) avg. S.I.
0 923
100 923
200 923
500 922
1000 920
Ra-226 Ingrowth Calcs_MWH:Ra-226 Ingrowth (Cell 2)8/10/2012
Denison Mines (USA) Corp. White Mesa Mill
Tailings Cell 3
Calculation of Ra-226 Concentrations Due to Future Decay of Th-230
The RA-226 concentration at various times in the future depends on both the decay of the Ra-226 currently
present and the ingrowth from Th-230. The Ra-226 decays with a half-life of 1602 years. The ingrowth is also
a function of the Ra-226 half-life (1602 years) and the Th-230 half-life (77,000 years).
A (Ra-226) at a time t (years) = [A (Ra-226) at t=0][exp(-0.693t/1602 years)]
A (Ra-226 from decay of Th-230 at time t (years)) = [A (Th-230)][1-exp(-0.693t/1602 years)][exp(-0.693t/77,000 years)]
Residual Ra-226 at time t
Time exp (-0.693t/1602) Initial Ra-226 Concentration (pCi/g) Ra-226 Concentration at time t (pCi/g)
(years) Cell 3 Cell 3
0 1.000 606 606
100 0.958 606 580
200 0.917 606 556
500 0.805 606 488
1000 0.649 606 393
Ra-226 Concentration from Ingrowth Due to Decay of Th-230
Time exp (-0.693t/1602) Initial Th-230 Concentration (pCi/g) Ra-226 Concentration at time t (pCi/g) exp (-0.693t/77000)
(years) S.I.S.I.
0 1.000 1048 0 1.000
100 0.958 1048 44 0.999
200 0.917 1048 87 0.998
500 0.805 1048 203 0.996
1000 0.649 1048 365 0.991
Total Ra-226 Concentration at Time t (original Ra-226 and Ra-226 from Th-230 decay)
Time Total Ra-226 Concentration (pCi/g)
(years) avg. S.I.
0 606
100 625
200 642
500 691
1000 758
Ra-226 Ingrowth Calcs_MWH:Ra-226 Ingrowth (Cell 3)8/10/2012
Denison Mines (USA) Corp. White Mesa Mill
Tailings Cells 4A/B
Calculation of Ra-226 Concentrations Due to Future Decay of Th-230
The RA-226 concentration at various times in the future depends on both the decay of the Ra-226 currently
present and the ingrowth from Th-230. The Ra-226 decays with a half-life of 1602 years. The ingrowth is also
a function of the Ra-226 half-life (1602 years) and the Th-230 half-life (77,000 years).
A (Ra-226) at a time t (years) = [A (Ra-226) at t=0][exp(-0.693t/1602 years)]
A (Ra-226 from decay of Th-230 at time t (years)) = [A (Th-230)][1-exp(-0.693t/1602 years)][exp(-0.693t/77,000 years)]
Residual Ra-226 at time t
Time exp (-0.693t/1602) Initial Ra-226 Concentration (pCi/g) Ra-226 Concentration at time t (pCi/g)
(years) Cell 4A/B Cell 4A/B
0 1.000 617 617
100 0.958 617 591
200 0.917 617 566
500 0.805 617 497
1000 0.649 617 400
Ra-226 Concentration from Ingrowth Due to Decay of Th-230
Time exp (-0.693t/1602) Initial Th-230 Concentration (pCi/g) Ra-226 Concentration at time t (pCi/g) exp (-0.693t/77000)
(years) S.I.S.I.
0 1.000 695 0 1.000
100 0.958 695 29 0.999
200 0.917 695 57 0.998
500 0.805 695 135 0.996
1000 0.649 695 242 0.991
Total Ra-226 Concentration at Time t (original Ra-226 and Ra-226 from Th-230 decay)
Time Total Ra-226 Concentration (pCi/g)
(years) avg. S.I.
0 617
100 620
200 623
500 632
1000 642
Ra-226 Ingrowth Calcs_MWH:Ra-226 Ingrowth (Cells 4A-B)8/10/2012

ATTACHMENT C.2
COVER MATERIAL PARAMETERS ESTIMATION TABLE
DENISON MINES WHITE MESA MILL
Summary of Laboratory Testing Results for Borrow Stockpiles
Borrow Stockpile ID
Estimated 
Stockpile 
Volume1 (cy)
Field 
Investigation 
Date Material Description USCS Sample ID
Sample Depth 
(ft)
Gravimetric 
Water Content 
(%)
Atterberg Limits2 
LL/PL/PI (%) PI
Specific 
Gravity % Gravel %Sand %Silt % Clay
Max. 
Density 
(pcf)
Opt. 
Moist. 
Cont. (%)
Ksat 
(cm/s)
15bar 
Grav. 
Water 
Content 
(%) Soil Group4
E1 15,900 Apr‐2012 Topsoil (Sandy Silty Clay) CL‐ML E1‐A0 ‐ 3 ‐‐23/18/5 5 2.61 0 41 43 16 118 11 1.3 x 10‐4 5.2 Topsoil
SM A 5 4.5 NP NP ‐‐0.5 77.1 13.5 8.9 B
SC B 12 5.7 23.3/11.2/12.1 12.1 2.64 13.1 50.3 22.6 14.0 U
E3 16,800 Apr‐2012 Clay with Sand CH E3‐A0 ‐ 3 ‐‐54/24/30 30 2.53 0 23 29 48 105 19 9.5 x 10‐5 13.6 F
E4 66,600 Oct‐2010 Sandy Clay CL A 5 8.6 30.3/14.4/15.9 15.9 ‐‐0.0 41.2 39.1 19.7 U
Oct‐2010 Sandy Clay CL A 6 9.0 33.2/14.3/18.9 18.9 ‐‐0.0 35.5 38.1 26.4 F
Apr‐2012 Clay with Sand CH E5‐B0 ‐ 3 ‐‐51/24/27 27 2.56 2 15 36 47 F
E6 100,700 Oct‐2010 Clay CL A 5 14.4 40.2/15.8/24.4 24.4 2.74 0.1 17.7 49.5 32.7 F
E7 74,900 Oct‐2010 Sandy Clay CL A 6 5.7 26.2/16.3/9.9 9.9 ‐‐0.0 30.2 56.1 13.7 U
Oct‐2010 Sandy Clay CL A 2 7.4 23.0/12.0/11.0 11.0 ‐‐0.0 47.0 36.9 16.1 U
Apr‐2012 Gravel with Clay and Sand GW‐GC E8‐B0 ‐ 4 ‐‐27/16/11 11 2.63 40.0 31.0 18.0 11.0 125 11 6.0 B
W1 85,700 Oct‐2010 Sandy Clay CL A 5 8.8 32.1/14.5/17.6 17.6 ‐‐0.0 40.6 37.6 21.8 U
Oct‐2010 Sandy Clay CL A surface 8.5 28.1/13.1/15.0 15.0 ‐‐0.2 41.5 42.5 15.8 U
Apr‐2012 Clayey Sand with Gravel SC W2‐A0 ‐ 3 ‐‐24/14/10 10 2.62 30 45 15.0 10.0 6.9 B
Apr‐2012 Silty Clayey Sand with Gravel SC‐SM W2‐B0 ‐ 5 ‐‐18/13/5 5 2.63 41 45 9.0 5.0 128 9 1.5 x 10‐3 3.5 B
W3 84,800 Oct‐2010 Topsoil (Sandy Silty Clay) CL‐ML A surface 4.3 20.9/16.2/4.7 4.7 ‐‐0.2 44.2 39.2 16.4 Topsoil
Oct‐2010 Topsoil  (Sandy Silt) ML A 5 5.3 21.9/18.0/3.9 3.9 ‐‐0.0 32.6 54.3 13.1 Topsoil
Apr‐2012 Topsoil (Sandy Silty Clay) CL‐ML W4‐B0 ‐ 4 ‐‐26/19/7 7 2.60 0 38 44 18 Topsoil
Sandy Clay CL W5‐A0 ‐ 4 ‐‐27/18/9 9 2.61 1 49 32 18 7.0 U
Clayey Sand with Gravel SC W5‐B0 ‐ 4 ‐‐24/15/9 9 2.63 29 44 19 8 122 10 1.1 x 10‐3 3.6 B
W6 93,400 Oct‐2010 Topsoil (Sandy Silty Clay) CL‐ML A surface 3.3 23.1/16.5/6.6 6.6 ‐‐0.0 34.3 51.8 13.9 Topsoil
W7 39,500 Oct‐2010 Sandy Clay CL A 5 8.7 28.0/10.6/17.3 17.3 2.67 0.0 43.8 43.1 13.1 U
Silty Sand with Gravel SM W8‐A0 ‐ 3 ‐‐NP NP 2.64 35 51 9 5 117 13 1.2 x 10‐3 5.0 B
Silty Sand with Gravel SM W8‐B0 ‐ 4 ‐‐NP NP 2.66 32 40 18 10 6.4 B
Oct‐2010 Sandy Clay CL A surface 4.4 25.9/12.3/13.5 13.5 ‐‐0.0 37.4 45.2 17.4 U
Apr‐2012 Sandy Clay CL W9‐B0 ‐ 4 ‐‐28/16/12 12 2.63 6 44 35 15 115 14 4.1 x 10‐4 7.7 U
Notes:  
1.  Volumes estimated using 2009 topography and assuming a relatively flat bottom surface, except for stockpiles W5, W8 and W9.  The volumes for stockpiles  W8 and W9 were estimated by comparing the 2011 versus 2009 topography.  
The volume for stockpile W5 was estimated using a combination of both methods.  
2.  LL = Liquid Limt, PL = Plastic Limit, PI = Plasticity Index (PI = LL‐PL)
3.  Gravel = 4.75 mm to 75 mm, Sand = 0.075 mm to 4.75 mm, Fines:  Silt = 0 .075 mm to 0.002 mm, Clay = less than 0.002 mm
4.  Group B (broadly graded), Group U (uniformly graded), and Group F (fine textured) based on evaluation of gradations and Benson (2012)*.   See Appendix A.2 for gradations.  
*Benson, C., 2012.  Electronic communication from Craig Benson, University of Wisconsin‐Madison, to Melanie Davis, MWH Americas, Inc., regarding evaluation of gradations performed for potential cover soils for White Mesa, May 20.  
Estimation of Cover Material Properties Used in Model
Soil Group4 Volume (cy) Total Vol (cy) Percent  of Total Volume 
Ave. Max. 
Dry Density 
(pcf)
Ave. Specific 
Gravity 
Ave. 15bar 
Grav. Water 
Content (%)
Group B 1,728,308         3,596,621       48.1% 123 2.64 5.2
Group U 1,682,013         3,596,621       46.8% 115 2.64 7.3
Group F 186,300             3,596,621       5.2% 105 2.61 13.6
118 2.63 6.7Weighted Ave. 
W9 60,250
W5 2,001,160 Apr‐2012
W8 178,411 Apr‐2012
E8 227,300
W2 584,500
W4 90,000
E2 92,000 Oct‐2010 Silty Sand/Clayey Sand 
E5 68,800
White Mesa_2010 and 2012 lab results_8‐6‐12.xlsx:Cover Mat Props in Model

ATTACHMENT C.3
RADON MODEL OUTPUT
-----*****! RADON !*****-----

Version 1.2 - MAY 22, 1989 - G.F. Birchard tel.# [phone]
U.S. Nuclear Regulatory Commission Office of Research

RADON FLUX, CONCENTRATION AND TAILINGS COVER THICKNESS
ARE CALCULATED FOR MULTIPLE LAYERS

OUTPUT FILE: Cell2_modeloutput
DESCRIPTION: Radon model output for cell 2 to determine layer thickness

CONSTANTS

RADON DECAY CONSTANT .0000021 s^-1
RADON WATER/AIR PARTITION COEFFICIENT .26
DEFAULT SPECIFIC GRAVITY OF COVER & TAILINGS 2.65

GENERAL INPUT PARAMETERS

LAYERS OF COVER AND TAILINGS 5
DEFAULT RADON FLUX LIMIT 20 pCi m^-2 s^-1
NO. OF THE LAYER TO BE OPTIMIZED 3
DEFAULT SURFACE RADON CONCENTRATION 0 pCi l^-1
SURFACE FLUX PRECISION .01 pCi m^-2 s^-1
LAYER INPUT PARAMETERS

LAYER 1 Tailings
THICKNESS 500 cm
CALCULATED POROSITY 0.472
MEASURED MASS DENSITY 1.4 g cm^-3
MEASURED RADIUM ACTIVITY 923 pCi/g^-1
MEASURED EMANATION COEFFICIENT .2
CALCULATED SOURCE TERM CONCENTRATION 1.151D-03 pCi cm^-3 s^-1
WEIGHT % MOISTURE 6 %
MOISTURE SATURATION FRACTION .178
MEASURED DIFFUSION COEFFICIENT .0404 cm^2 s^-1

LAYER 2 Lower Random Fill (80% SP Compaction)
THICKNESS 76 cm
POROSITY .43
MEASURED MASS DENSITY 1.5 g cm^-3
MEASURED RADIUM ACTIVITY 0 pCi/g^-1
MEASURED EMANATION COEFFICIENT .35
CALCULATED SOURCE TERM CONCENTRATION 0.000D+00 pCi cm^-3 s^-1
WEIGHT % MOISTURE 6.7 %
MOISTURE SATURATION FRACTION .234
MEASURED DIFFUSION COEFFICIENT .0322 cm^2 s^-1

LAYER 3 Random Fill (95%SP Compaction)
THICKNESS 1 cm
POROSITY .32
MEASURED MASS DENSITY 1.8 g cm^-3
MEASURED RADIUM ACTIVITY 0 pCi/g^-1
MEASURED EMANATION COEFFICIENT .35
CALCULATED SOURCE TERM CONCENTRATION 0.000D+00 pCi cm^-3 s^-1
WEIGHT % MOISTURE 6.7 %
MOISTURE SATURATION FRACTION .377
MEASURED DIFFUSION COEFFICIENT .0176 cm^2 s^-1

LAYER 4 ET Layer (85% SP Compaction)
THICKNESS 107 cm
POROSITY .39
MEASURED MASS DENSITY 1.6 g cm^-3
MEASURED RADIUM ACTIVITY 0 pCi/g^-1
MEASURED EMANATION COEFFICIENT .35
CALCULATED SOURCE TERM CONCENTRATION 0.000D+00 pCi cm^-3 s^-1
WEIGHT % MOISTURE 6.7 %
MOISTURE SATURATION FRACTION .275
MEASURED DIFFUSION COEFFICIENT .0275 cm^2 s^-1

LAYER 5 Topsoil
THICKNESS 15 cm
POROSITY .35
MEASURED MASS DENSITY 1.7 g cm^-3
MEASURED RADIUM ACTIVITY 0 pCi/g^-1
MEASURED EMANATION COEFFICIENT .35
CALCULATED SOURCE TERM CONCENTRATION 0.000D+00 pCi cm^-3 s^-1
WEIGHT % MOISTURE 4 %
MOISTURE SATURATION FRACTION .194
MEASURED DIFFUSION COEFFICIENT .0351 cm^2 s^-1

DATA SENT TO THE FILE `RNDATA' ON DRIVE A:

N F01 CN1 ICOST CRITJ ACC
5 -1.000D+00 0.000D+00 3 2.000D+01 1.000D-02

LAYER DX D P Q XMS RHO
1 5.000D+02 4.040D-02 4.717D-01 1.151D-03 1.781D-01 1.400
2 7.600D+01 3.220D-02 4.300D-01 0.000D+00 2.337D-01 1.500
3 1.000D+00 1.760D-02 3.200D-01 0.000D+00 3.769D-01 1.800
4 1.070D+02 2.750D-02 3.900D-01 0.000D+00 2.749D-01 1.600
5 1.500D+01 3.510D-02 3.500D-01 0.000D+00 1.943D-01 1.700

BARE SOURCE FLUX FROM LAYER 1: 7.318D+02 pCi m^-2 s^-1
RESULTS OF THE RADON DIFFUSION CALCULATIONS
LAYER THICKNESS EXIT FLUX EXIT CONC.
(cm) (pCi m^-2 s^-1) (pCi l^-1)

1 5.000D+02 2.847D+02 3.259D+05
2 7.600D+01 1.133D+02 2.045D+05
3 1.429D+02 3.201D+01 2.407D+04
4 1.070D+02 2.021D+01 2.285D+03
5 1.500D+01 2.007D+01 0.000D+00
-----*****! RADON !*****-----

Version 1.2 - MAY 22, 1989 - G.F. Birchard tel.# [phone]
U.S. Nuclear Regulatory Commission Office of Research

RADON FLUX, CONCENTRATION AND TAILINGS COVER THICKNESS
ARE CALCULATED FOR MULTIPLE LAYERS

OUTPUT FILE: Cell3_modeloutput
DESCRIPTION: Radon model output for cell 3 to determine layer thickness

CONSTANTS

RADON DECAY CONSTANT .0000021 s^-1
RADON WATER/AIR PARTITION COEFFICIENT .26
DEFAULT SPECIFIC GRAVITY OF COVER & TAILINGS 2.65

GENERAL INPUT PARAMETERS

LAYERS OF COVER AND TAILINGS 5
DEFAULT RADON FLUX LIMIT 20 pCi m^-2 s^-1
NO. OF THE LAYER TO BE OPTIMIZED 3
DEFAULT SURFACE RADON CONCENTRATION 0 pCi l^-1
SURFACE FLUX PRECISION .01 pCi m^-2 s^-1
LAYER INPUT PARAMETERS

LAYER 1 Tailings
THICKNESS 500 cm
POROSITY .47
MEASURED MASS DENSITY 1.4 g cm^-3
MEASURED RADIUM ACTIVITY 758 pCi/g^-1
MEASURED EMANATION COEFFICIENT .2
CALCULATED SOURCE TERM CONCENTRATION 9.483D-04 pCi cm^-3 s^-1
WEIGHT % MOISTURE 6 %
MOISTURE SATURATION FRACTION .179
CALCULATED DIFFUSION COEFFICIENT 4.008D-02 cm^2 s^-1

LAYER 2 Lower Random Fill (80% SP compaction)
THICKNESS 76 cm
POROSITY .43
MEASURED MASS DENSITY 1.5 g cm^-3
MEASURED RADIUM ACTIVITY 0 pCi/g^-1
MEASURED EMANATION COEFFICIENT .35
CALCULATED SOURCE TERM CONCENTRATION 0.000D+00 pCi cm^-3 s^-1
WEIGHT % MOISTURE 6.7 %
MOISTURE SATURATION FRACTION .234
CALCULATED DIFFUSION COEFFICIENT 3.258D-02 cm^2 s^-1

LAYER 3 Random Fill (95% SP compaction)
THICKNESS 1 cm
POROSITY .32
MEASURED MASS DENSITY 1.8 g cm^-3
MEASURED RADIUM ACTIVITY 0 pCi/g^-1
MEASURED EMANATION COEFFICIENT .35
CALCULATED SOURCE TERM CONCENTRATION 0.000D+00 pCi cm^-3 s^-1
WEIGHT % MOISTURE 6.7 %
MOISTURE SATURATION FRACTION .377
CALCULATED DIFFUSION COEFFICIENT 1.755D-02 cm^2 s^-1

LAYER 4 ET Layer (random fill at 85% SP compaction)
THICKNESS 107 cm
POROSITY .39
MEASURED MASS DENSITY 1.6 g cm^-3
MEASURED RADIUM ACTIVITY 0 pCi/g^-1
MEASURED EMANATION COEFFICIENT .35
CALCULATED SOURCE TERM CONCENTRATION 0.000D+00 pCi cm^-3 s^-1
WEIGHT % MOISTURE 6.7 %
MOISTURE SATURATION FRACTION .275
CALCULATED DIFFUSION COEFFICIENT 2.738D-02 cm^2 s^-1

LAYER 5 Topsoil
THICKNESS 15 cm
POROSITY .38
MEASURED MASS DENSITY 1.6 g cm^-3
MEASURED RADIUM ACTIVITY 0 pCi/g^-1
MEASURED EMANATION COEFFICIENT .38
CALCULATED SOURCE TERM CONCENTRATION 0.000D+00 pCi cm^-3 s^-1
WEIGHT % MOISTURE 5.2 %
MOISTURE SATURATION FRACTION .219
CALCULATED DIFFUSION COEFFICIENT 3.302D-02 cm^2 s^-1

DATA SENT TO THE FILE `RNDATA' ON DRIVE A:

N F01 CN1 ICOST CRITJ ACC
5 -1.000D+00 0.000D+00 3 2.000D+01 1.000D-02

LAYER DX D P Q XMS RHO
1 5.000D+02 4.008D-02 4.700D-01 9.483D-04 1.787D-01 1.400
2 7.600D+01 3.258D-02 4.300D-01 0.000D+00 2.337D-01 1.500
3 1.000D+00 1.755D-02 3.200D-01 0.000D+00 3.769D-01 1.800
4 1.070D+02 2.738D-02 3.900D-01 0.000D+00 2.749D-01 1.600
5 1.500D+01 3.302D-02 3.800D-01 0.000D+00 2.189D-01 1.600

BARE SOURCE FLUX FROM LAYER 1: 5.988D+02 pCi m^-2 s^-1

RESULTS OF THE RADON DIFFUSION CALCULATIONS
LAYER THICKNESS EXIT FLUX EXIT CONC.
(cm) (pCi m^-2 s^-1) (pCi l^-1)

1 5.000D+02 2.351D+02 2.672D+05
2 7.600D+01 9.438D+01 1.680D+05
3 1.247D+02 3.220D+01 2.428D+04
4 1.070D+02 2.030D+01 2.295D+03
5 1.500D+01 2.015D+01 0.000D+00
-----*****! RADON !*****-----

Version 1.2 - MAY 22, 1989 - G.F. Birchard tel.# [phone]
U.S. Nuclear Regulatory Commission Office of Research

RADON FLUX, CONCENTRATION AND TAILINGS COVER THICKNESS
ARE CALCULATED FOR MULTIPLE LAYERS

OUTPUT FILE: Cells4AB_modeloutput
DESCRIPTION: Radon model output for cells 4A and 4B

CONSTANTS

RADON DECAY CONSTANT .0000021 s^-1
RADON WATER/AIR PARTITION COEFFICIENT .26
DEFAULT SPECIFIC GRAVITY OF COVER & TAILINGS 2.65

GENERAL INPUT PARAMETERS

LAYERS OF COVER AND TAILINGS 5
DEFAULT RADON FLUX LIMIT 20 pCi m^-2 s^-1
NO. OF THE LAYER TO BE OPTIMIZED 3
DEFAULT SURFACE RADON CONCENTRATION 0 pCi l^-1
SURFACE FLUX PRECISION .01 pCi m^-2 s^-1
LAYER INPUT PARAMETERS

LAYER 1 Tailings
THICKNESS 500 cm
POROSITY .47
MEASURED MASS DENSITY 1.4 g cm^-3
MEASURED RADIUM ACTIVITY 642 pCi/g^-1
MEASURED EMANATION COEFFICIENT .2
CALCULATED SOURCE TERM CONCENTRATION 8.032D-04 pCi cm^-3 s^-1
WEIGHT % MOISTURE 6 %
MOISTURE SATURATION FRACTION .179
CALCULATED DIFFUSION COEFFICIENT 4.008D-02 cm^2 s^-1

LAYER 2 Lower Random Fill (80% SP compaction)
THICKNESS 76 cm
POROSITY .43
MEASURED MASS DENSITY 1.5 g cm^-3
MEASURED RADIUM ACTIVITY 0 pCi/g^-1
MEASURED EMANATION COEFFICIENT .35
CALCULATED SOURCE TERM CONCENTRATION 0.000D+00 pCi cm^-3 s^-1
WEIGHT % MOISTURE 6.7 %
MOISTURE SATURATION FRACTION .234
CALCULATED DIFFUSION COEFFICIENT 3.258D-02 cm^2 s^-1

LAYER 3 Random Fill (95% SP compaction)
THICKNESS 1 cm
POROSITY .32
MEASURED MASS DENSITY 1.8 g cm^-3
MEASURED RADIUM ACTIVITY 0 pCi/g^-1
MEASURED EMANATION COEFFICIENT .35
CALCULATED SOURCE TERM CONCENTRATION 0.000D+00 pCi cm^-3 s^-1
WEIGHT % MOISTURE 6.7 %
MOISTURE SATURATION FRACTION .377
CALCULATED DIFFUSION COEFFICIENT 1.755D-02 cm^2 s^-1

LAYER 4 ET Layer (random fill at 85% SP compaction)
THICKNESS 107 cm
POROSITY .39
MEASURED MASS DENSITY 1.6 g cm^-3
MEASURED RADIUM ACTIVITY 0 pCi/g^-1
MEASURED EMANATION COEFFICIENT .35
CALCULATED SOURCE TERM CONCENTRATION 0.000D+00 pCi cm^-3 s^-1
WEIGHT % MOISTURE 6.7 %
MOISTURE SATURATION FRACTION .275
CALCULATED DIFFUSION COEFFICIENT 2.738D-02 cm^2 s^-1

LAYER 5 Rock Mulch
THICKNESS 15 cm
POROSITY .35
MEASURED MASS DENSITY 1.7 g cm^-3
MEASURED RADIUM ACTIVITY 0 pCi/g^-1
MEASURED EMANATION COEFFICIENT .35
CALCULATED SOURCE TERM CONCENTRATION 0.000D+00 pCi cm^-3 s^-1
WEIGHT % MOISTURE 4 %
MOISTURE SATURATION FRACTION .194
CALCULATED DIFFUSION COEFFICIENT 3.536D-02 cm^2 s^-1

DATA SENT TO THE FILE `RNDATA' ON DRIVE A:

N F01 CN1 ICOST CRITJ ACC
5 -1.000D+00 0.000D+00 3 2.000D+01 1.000D-02

LAYER DX D P Q XMS RHO
1 5.000D+02 4.008D-02 4.700D-01 8.032D-04 1.787D-01 1.400
2 7.600D+01 3.258D-02 4.300D-01 0.000D+00 2.337D-01 1.500
3 1.000D+00 1.755D-02 3.200D-01 0.000D+00 3.769D-01 1.800
4 1.070D+02 2.738D-02 3.900D-01 0.000D+00 2.749D-01 1.600
5 1.500D+01 3.536D-02 3.500D-01 0.000D+00 1.943D-01 1.700

BARE SOURCE FLUX FROM LAYER 1: 5.072D+02 pCi m^-2 s^-1

RESULTS OF THE RADON DIFFUSION CALCULATIONS
LAYER THICKNESS EXIT FLUX EXIT CONC.
(cm) (pCi m^-2 s^-1) (pCi l^-1)

1 5.000D+02 1.997D+02 2.259D+05
2 7.600D+01 8.091D+01 1.414D+05
3 1.102D+02 3.207D+01 2.417D+04
4 1.070D+02 2.023D+01 2.271D+03
5 1.500D+01 2.009D+01 0.000D+00

ATTACHMENT C.4
RADON MODEL OUTPUT FOR VARIABLE THICKNESS OF RANDOM FILL
-----*****! RADON !*****-----
Version 1.2 - MAY 22, 1989 - G.F. Birchard tel.# [phone]
U.S. Nuclear Regulatory Commission Office of Research
RADON FLUX, CONCENTRATION AND TAILINGS COVER THICKNESS
ARE CALCULATED FOR MULTIPLE LAYERS
OUTPUT FILE: Cell2_Layer3thicknessredux1
DESCRIPTION: White Mesa Mill Cell 2 95% Random Fill thickness reduction
point 1 on figure C.1
CONSTANTS
RADON DECAY CONSTANT .0000021 s^-1
RADON WATER/AIR PARTITION COEFFICIENT .26
DEFAULT SPECIFIC GRAVITY OF COVER & TAILINGS 2.65
GENERAL INPUT PARAMETERS
LAYERS OF COVER AND TAILINGS 5
DEFAULT RADON FLUX LIMIT 20 pCi m^-2 s^-1
NO. OF THE LAYER TO BE OPTIMIZED 3
DEFAULT SURFACE RADON CONCENTRATION 0 pCi l^-1
SURFACE FLUX PRECISION .01 pCi m^-2 s^-1
LAYER INPUT PARAMETERS
LAYER 1 Tailings
THICKNESS 500 cm
CALCULATED POROSITY 0.472
MEASURED MASS DENSITY 1.4 g cm^-3
MEASURED RADIUM ACTIVITY 923 pCi/g^-1
MEASURED EMANATION COEFFICIENT .2
CALCULATED SOURCE TERM CONCENTRATION 1.151D-03 pCi cm^-3 s^-1
WEIGHT % MOISTURE 6 %
MOISTURE SATURATION FRACTION .178
MEASURED DIFFUSION COEFFICIENT .0404 cm^2 s^-1
LAYER 2 Lower Random Fill (80% SP Compaction)
THICKNESS 76 cm
POROSITY .43
MEASURED MASS DENSITY 1.5 g cm^-3
MEASURED RADIUM ACTIVITY 0 pCi/g^-1
MEASURED EMANATION COEFFICIENT .35
CALCULATED SOURCE TERM CONCENTRATION 0.000D+00 pCi cm^-3 s^-1
WEIGHT % MOISTURE 6.7 %
MOISTURE SATURATION FRACTION .234
MEASURED DIFFUSION COEFFICIENT .0322 cm^2 s^-1
LAYER 3 Random Fill (95%SP Compaction)
THICKNESS 1 cm
POROSITY .32
MEASURED MASS DENSITY 1.8 g cm^-3
MEASURED RADIUM ACTIVITY 0 pCi/g^-1
MEASURED EMANATION COEFFICIENT .35
CALCULATED SOURCE TERM CONCENTRATION 0.000D+00 pCi cm^-3 s^-1
WEIGHT % MOISTURE 6.7 %
MOISTURE SATURATION FRACTION .377
MEASURED DIFFUSION COEFFICIENT .0176 cm^2 s^-1
LAYER 4 ET Layer (85% SP Compaction)
THICKNESS 107 cm
POROSITY .39
MEASURED MASS DENSITY 1.6 g cm^-3
MEASURED RADIUM ACTIVITY 0 pCi/g^-1
MEASURED EMANATION COEFFICIENT .35
CALCULATED SOURCE TERM CONCENTRATION 0.000D+00 pCi cm^-3 s^-1
WEIGHT % MOISTURE 6.7 %
MOISTURE SATURATION FRACTION .275
MEASURED DIFFUSION COEFFICIENT .0275 cm^2 s^-1
LAYER 5 Topsoil
THICKNESS 15 cm
POROSITY .35
MEASURED MASS DENSITY 1.7 g cm^-3
MEASURED RADIUM ACTIVITY 0 pCi/g^-1
MEASURED EMANATION COEFFICIENT .35
CALCULATED SOURCE TERM CONCENTRATION 0.000D+00 pCi cm^-3 s^-1
WEIGHT % MOISTURE 4 %
MOISTURE SATURATION FRACTION .194
MEASURED DIFFUSION COEFFICIENT .0351 cm^2 s^-1
DATA SENT TO THE FILE `RNDATA' ON DRIVE A:
N F01 CN1 ICOST CRITJ ACC
5 -1.000D+00 0.000D+00 3 2.000D+01 1.000D-02
LAYER DX D P Q XMS RHO
1 5.000D+02 4.040D-02 4.717D-01 1.151D-03 1.781D-01 1.400
2 7.600D+01 3.220D-02 4.300D-01 0.000D+00 2.337D-01 1.500
3 1.000D+00 1.760D-02 3.200D-01 0.000D+00 3.769D-01 1.800
4 1.070D+02 2.750D-02 3.900D-01 0.000D+00 2.749D-01 1.600
5 1.500D+01 3.510D-02 3.500D-01 0.000D+00 1.943D-01 1.700
BARE SOURCE FLUX FROM LAYER 1: 7.318D+02 pCi m^-2 s^-1
RESULTS OF THE RADON DIFFUSION CALCULATIONS
LAYER THICKNESS EXIT FLUX EXIT CONC.
(cm) (pCi m^-2 s^-1) (pCi l^-1)
1 5.000D+02 2.847D+02 3.259D+05
2 7.600D+01 1.133D+02 2.045D+05
3 1.429D+02 3.201D+01 2.407D+04
4 1.070D+02 2.021D+01 2.285D+03
5 1.500D+01 2.007D+01 0.000D+00
-----*****! RADON !*****-----
Version 1.2 - MAY 22, 1989 - G.F. Birchard tel.# [phone]
U.S. Nuclear Regulatory Commission Office of Research
RADON FLUX, CONCENTRATION AND TAILINGS COVER THICKNESS
ARE CALCULATED FOR MULTIPLE LAYERS
OUTPUT FILE: Cell2_Layer3thicknessredux2
DESCRIPTION: White Mesa Mill Cell 2 95% Random Fill thickness reduction
point 2 on figure C.1
CONSTANTS
RADON DECAY CONSTANT .0000021 s^-1
RADON WATER/AIR PARTITION COEFFICIENT .26
DEFAULT SPECIFIC GRAVITY OF COVER & TAILINGS 2.65
GENERAL INPUT PARAMETERS
LAYERS OF COVER AND TAILINGS 5
DEFAULT RADON FLUX LIMIT 20 pCi m^-2 s^-1
NO. OF THE LAYER TO BE OPTIMIZED 3
DEFAULT SURFACE RADON CONCENTRATION 0 pCi l^-1
SURFACE FLUX PRECISION .01 pCi m^-2 s^-1
LAYER INPUT PARAMETERS
LAYER 1 Tailings
THICKNESS 500 cm
POROSITY .47
MEASURED MASS DENSITY 1.4 g cm^-3
MEASURED RADIUM ACTIVITY 923 pCi/g^-1
MEASURED EMANATION COEFFICIENT .2
CALCULATED SOURCE TERM CONCENTRATION 1.155D-03 pCi cm^-3 s^-1
WEIGHT % MOISTURE 6 %
MOISTURE SATURATION FRACTION .179
MEASURED DIFFUSION COEFFICIENT .0404 cm^2 s^-1
LAYER 2 Lower Random Fill (80% SP Compaction)
THICKNESS 106.68 cm
POROSITY .43
MEASURED MASS DENSITY 1.5 g cm^-3
MEASURED RADIUM ACTIVITY 0 pCi/g^-1
MEASURED EMANATION COEFFICIENT .35
CALCULATED SOURCE TERM CONCENTRATION 0.000D+00 pCi cm^-3 s^-1
WEIGHT % MOISTURE 6.7 %
MOISTURE SATURATION FRACTION .234
MEASURED DIFFUSION COEFFICIENT .0322 cm^2 s^-1
LAYER 3 Random Fill (95% SP Compaction)
THICKNESS 1 cm
POROSITY .32
MEASURED MASS DENSITY 1.8 g cm^-3
MEASURED RADIUM ACTIVITY 0 pCi/g^-1
MEASURED EMANATION COEFFICIENT .35
CALCULATED SOURCE TERM CONCENTRATION 0.000D+00 pCi cm^-3 s^-1
WEIGHT % MOISTURE 6.7 %
MOISTURE SATURATION FRACTION .377
MEASURED DIFFUSION COEFFICIENT .0176 cm^2 s^-1
LAYER 4 ET Layer (85% SP Compaction)
THICKNESS 107 cm
POROSITY .39
MEASURED MASS DENSITY 1.6 g cm^-3
MEASURED RADIUM ACTIVITY 0 pCi/g^-1
MEASURED EMANATION COEFFICIENT .35
CALCULATED SOURCE TERM CONCENTRATION 0.000D+00 pCi cm^-3 s^-1
WEIGHT % MOISTURE 6.7 %
MOISTURE SATURATION FRACTION .275
MEASURED DIFFUSION COEFFICIENT .0275 cm^2 s^-1
LAYER 5 Topsoil
THICKNESS 15 cm
POROSITY .35
MEASURED MASS DENSITY 1.7 g cm^-3
MEASURED RADIUM ACTIVITY 0 pCi/g^-1
MEASURED EMANATION COEFFICIENT .35
CALCULATED SOURCE TERM CONCENTRATION 0.000D+00 pCi cm^-3 s^-1
WEIGHT % MOISTURE 4 %
MOISTURE SATURATION FRACTION .194
MEASURED DIFFUSION COEFFICIENT .0351 cm^2 s^-1
DATA SENT TO THE FILE `RNDATA' ON DRIVE A:
N F01 CN1 ICOST CRITJ ACC
5 -1.000D+00 0.000D+00 3 2.000D+01 1.000D-02
LAYER DX D P Q XMS RHO
1 5.000D+02 4.040D-02 4.700D-01 1.155D-03 1.787D-01 1.400
2 1.067D+02 3.220D-02 4.300D-01 0.000D+00 2.337D-01 1.500
3 1.000D+00 1.760D-02 3.200D-01 0.000D+00 3.769D-01 1.800
4 1.070D+02 2.750D-02 3.900D-01 0.000D+00 2.749D-01 1.600
5 1.500D+01 3.510D-02 3.500D-01 0.000D+00 1.943D-01 1.700
BARE SOURCE FLUX FROM LAYER 1: 7.318D+02 pCi m^-2 s^-1
RESULTS OF THE RADON DIFFUSION CALCULATIONS
LAYER THICKNESS EXIT FLUX EXIT CONC.
(cm) (pCi m^-2 s^-1) (pCi l^-1)
1 5.000D+02 2.996D+02 3.162D+05
2 1.067D+02 9.029D+01 1.598D+05
3 1.212D+02 3.202D+01 2.408D+04
4 1.070D+02 2.021D+01 2.286D+03
5 1.500D+01 2.008D+01 0.000D+00
-----*****! RADON !*****-----
Version 1.2 - MAY 22, 1989 - G.F. Birchard tel.# [phone]
U.S. Nuclear Regulatory Commission Office of Research
RADON FLUX, CONCENTRATION AND TAILINGS COVER THICKNESS
ARE CALCULATED FOR MULTIPLE LAYERS
OUTPUT FILE: Cell2_Layer3thicknessredux3
DESCRIPTION: White Mesa Mill Cell 2 95% Random Fill thickness reduction
point 3 on figure C.1
CONSTANTS
RADON DECAY CONSTANT .0000021 s^-1
RADON WATER/AIR PARTITION COEFFICIENT .26
DEFAULT SPECIFIC GRAVITY OF COVER & TAILINGS 2.65
GENERAL INPUT PARAMETERS
LAYERS OF COVER AND TAILINGS 5
DEFAULT RADON FLUX LIMIT 20 pCi m^-2 s^-1
NO. OF THE LAYER TO BE OPTIMIZED 3
DEFAULT SURFACE RADON CONCENTRATION 0 pCi l^-1
SURFACE FLUX PRECISION .01 pCi m^-2 s^-1
LAYER INPUT PARAMETERS
LAYER 1 Tailings
THICKNESS 500 cm
POROSITY .47
MEASURED MASS DENSITY 1.4 g cm^-3
MEASURED RADIUM ACTIVITY 923 pCi/g^-1
MEASURED EMANATION COEFFICIENT .2
CALCULATED SOURCE TERM CONCENTRATION 1.155D-03 pCi cm^-3 s^-1
WEIGHT % MOISTURE 6 %
MOISTURE SATURATION FRACTION .179
MEASURED DIFFUSION COEFFICIENT .0404 cm^2 s^-1
LAYER 2 Lower Random Fill (80% SP Compaction)
THICKNESS 152.4 cm
POROSITY .43
MEASURED MASS DENSITY 1.5 g cm^-3
MEASURED RADIUM ACTIVITY 0 pCi/g^-1
MEASURED EMANATION COEFFICIENT .35
CALCULATED SOURCE TERM CONCENTRATION 0.000D+00 pCi cm^-3 s^-1
WEIGHT % MOISTURE 6.7 %
MOISTURE SATURATION FRACTION .234
MEASURED DIFFUSION COEFFICIENT .0322 cm^2 s^-1
LAYER 3 Random Fill (95% SP Compaction)
THICKNESS 1 cm
POROSITY .32
MEASURED MASS DENSITY 1.8 g cm^-3
MEASURED RADIUM ACTIVITY 0 pCi/g^-1
MEASURED EMANATION COEFFICIENT .35
CALCULATED SOURCE TERM CONCENTRATION 0.000D+00 pCi cm^-3 s^-1
WEIGHT % MOISTURE 6.7 %
MOISTURE SATURATION FRACTION .377
MEASURED DIFFUSION COEFFICIENT .0176 cm^2 s^-1
LAYER 4 ET Layer (85% SP Compaction)
THICKNESS 107 cm
POROSITY .39
MEASURED MASS DENSITY 1.6 g cm^-3
MEASURED RADIUM ACTIVITY 0 pCi/g^-1
MEASURED EMANATION COEFFICIENT .35
CALCULATED SOURCE TERM CONCENTRATION 0.000D+00 pCi cm^-3 s^-1
WEIGHT % MOISTURE 6.7 %
MOISTURE SATURATION FRACTION .275
MEASURED DIFFUSION COEFFICIENT .0275 cm^2 s^-1
LAYER 5 Topsoil
THICKNESS 15 cm
POROSITY .35
MEASURED MASS DENSITY 1.7 g cm^-3
MEASURED RADIUM ACTIVITY 0 pCi/g^-1
MEASURED EMANATION COEFFICIENT .35
CALCULATED SOURCE TERM CONCENTRATION 0.000D+00 pCi cm^-3 s^-1
WEIGHT % MOISTURE 4 %
MOISTURE SATURATION FRACTION .194
MEASURED DIFFUSION COEFFICIENT .0351 cm^2 s^-1
DATA SENT TO THE FILE `RNDATA' ON DRIVE A:
N F01 CN1 ICOST CRITJ ACC
5 -1.000D+00 0.000D+00 3 2.000D+01 1.000D-02
LAYER DX D P Q XMS RHO
1 5.000D+02 4.040D-02 4.700D-01 1.155D-03 1.787D-01 1.400
2 1.524D+02 3.220D-02 4.300D-01 0.000D+00 2.337D-01 1.500
3 1.000D+00 1.760D-02 3.200D-01 0.000D+00 3.769D-01 1.800
4 1.070D+02 2.750D-02 3.900D-01 0.000D+00 2.749D-01 1.600
5 1.500D+01 3.510D-02 3.500D-01 0.000D+00 1.943D-01 1.700
BARE SOURCE FLUX FROM LAYER 1: 7.318D+02 pCi m^-2 s^-1
RESULTS OF THE RADON DIFFUSION CALCULATIONS
LAYER THICKNESS EXIT FLUX EXIT CONC.
(cm) (pCi m^-2 s^-1) (pCi l^-1)
1 5.000D+02 3.113D+02 3.076D+05
2 1.524D+02 6.499D+01 1.088D+05
3 8.813D+01 3.221D+01 2.422D+04
4 1.070D+02 2.033D+01 2.299D+03
5 1.500D+01 2.020D+01 0.000D+00
-----*****! RADON !*****-----
Version 1.2 - MAY 22, 1989 - G.F. Birchard tel.# [phone]
U.S. Nuclear Regulatory Commission Office of Research
RADON FLUX, CONCENTRATION AND TAILINGS COVER THICKNESS
ARE CALCULATED FOR MULTIPLE LAYERS
OUTPUT FILE: Cell2_Layer3thicknessredux4
DESCRIPTION: White Mesa Mill Cell 2 95% Random Fill thickness reduction
point 4 on figure C.1
CONSTANTS
RADON DECAY CONSTANT .0000021 s^-1
RADON WATER/AIR PARTITION COEFFICIENT .26
DEFAULT SPECIFIC GRAVITY OF COVER & TAILINGS 2.65
GENERAL INPUT PARAMETERS
LAYERS OF COVER AND TAILINGS 5
DEFAULT RADON FLUX LIMIT 20 pCi m^-2 s^-1
NO. OF THE LAYER TO BE OPTIMIZED 3
DEFAULT SURFACE RADON CONCENTRATION 0 pCi l^-1
SURFACE FLUX PRECISION .01 pCi m^-2 s^-1
LAYER INPUT PARAMETERS
LAYER 1 Tailings
THICKNESS 500 cm
POROSITY .47
MEASURED MASS DENSITY 1.4 g cm^-3
MEASURED RADIUM ACTIVITY 923 pCi/g^-1
MEASURED EMANATION COEFFICIENT .2
CALCULATED SOURCE TERM CONCENTRATION 1.155D-03 pCi cm^-3 s^-1
WEIGHT % MOISTURE 6 %
MOISTURE SATURATION FRACTION .179
MEASURED DIFFUSION COEFFICIENT .0404 cm^2 s^-1
LAYER 2 ET Cover (80% SP Compaction)
THICKNESS 284 cm
POROSITY .43
MEASURED MASS DENSITY 1.5 g cm^-3
MEASURED RADIUM ACTIVITY 0 pCi/g^-1
MEASURED EMANATION COEFFICIENT .35
CALCULATED SOURCE TERM CONCENTRATION 0.000D+00 pCi cm^-3 s^-1
WEIGHT % MOISTURE 6.7 %
MOISTURE SATURATION FRACTION .234
MEASURED DIFFUSION COEFFICIENT .0322 cm^2 s^-1
LAYER 3 Random Fill (95% SP Compaction)
THICKNESS 1 cm
POROSITY .32
MEASURED MASS DENSITY 1.8 g cm^-3
MEASURED RADIUM ACTIVITY 0 pCi/g^-1
MEASURED EMANATION COEFFICIENT .35
CALCULATED SOURCE TERM CONCENTRATION 0.000D+00 pCi cm^-3 s^-1
WEIGHT % MOISTURE 6.7 %
MOISTURE SATURATION FRACTION .377
MEASURED DIFFUSION COEFFICIENT .0176 cm^2 s^-1
LAYER 4 Random Fill (85% SP Compaction)
THICKNESS 107 cm
POROSITY .39
MEASURED MASS DENSITY 1.6 g cm^-3
MEASURED RADIUM ACTIVITY 0 pCi/g^-1
MEASURED EMANATION COEFFICIENT .35
CALCULATED SOURCE TERM CONCENTRATION 0.000D+00 pCi cm^-3 s^-1
WEIGHT % MOISTURE 6.7 %
MOISTURE SATURATION FRACTION .275
MEASURED DIFFUSION COEFFICIENT .0275 cm^2 s^-1
LAYER 5 Topsoil
THICKNESS 15 cm
POROSITY .35
MEASURED MASS DENSITY 1.7 g cm^-3
MEASURED RADIUM ACTIVITY 0 pCi/g^-1
MEASURED EMANATION COEFFICIENT .35
CALCULATED SOURCE TERM CONCENTRATION 0.000D+00 pCi cm^-3 s^-1
WEIGHT % MOISTURE 4 %
MOISTURE SATURATION FRACTION .194
MEASURED DIFFUSION COEFFICIENT .0351 cm^2 s^-1
DATA SENT TO THE FILE `RNDATA' ON DRIVE A:
N F01 CN1 ICOST CRITJ ACC
5 -1.000D+00 0.000D+00 3 2.000D+01 1.000D-02
LAYER DX D P Q XMS RHO
1 5.000D+02 4.040D-02 4.700D-01 1.155D-03 1.787D-01 1.400
2 2.840D+02 3.220D-02 4.300D-01 0.000D+00 2.337D-01 1.500
3 1.000D+00 1.760D-02 3.200D-01 0.000D+00 3.769D-01 1.800
4 1.070D+02 2.750D-02 3.900D-01 0.000D+00 2.749D-01 1.600
5 1.500D+01 3.510D-02 3.500D-01 0.000D+00 1.943D-01 1.700
BARE SOURCE FLUX FROM LAYER 1: 7.318D+02 pCi m^-2 s^-1
RESULTS OF THE RADON DIFFUSION CALCULATIONS
LAYER THICKNESS EXIT FLUX EXIT CONC.
(cm) (pCi m^-2 s^-1) (pCi l^-1)
1 5.000D+02 3.206D+02 3.008D+05
2 2.840D+02 3.247D+01 2.882D+04
3 1.587D+00 3.221D+01 2.422D+04
4 1.070D+02 2.033D+01 2.300D+03
5 1.500D+01 2.020D+01 0.000D+00

ATTACHMENT I

SUPPORTING DOCUMENTATION FOR INTERROGATORY 13/1:

THE RADIUM BENCHMARK DOSE APPROACH

350496-009

15 August 2012

Jo Ann Tischler
Director, Compliance and Permitting
Energy Fuels Resources (USA) Inc.
1050 17th Street, Suite 950
Denver, CO 80265 Via Email: [e-mail]

Re: Attachment I – The Radium Benchmark Dose Approach

Dear Jo Ann,

This letter report provides a summary of SENES’ RESRAD modeling in support of Energy Fuels
Resources response to interrogatories on the White Mesa Mill (the “Mill”) Reclamation Plan.
Based on our discussions and subsequent memorandum of 4 July 2012 (Support for White Mesa
Mill Interrogatories), SENES proposed to develop a sum rule for relevant radionuclides by
determining the concentration limits based on the radium benchmark approach in accordance
with Appendix H of NUREG 1620.

This letter report is referred to as Attachment I in Response to Interrogatories – Round 1 for
Reclamation Plan, Revision 5.0, March 2012.

The Radium Benchmark Approach

The radium benchmark dose (RBD) approach was used to develop soil concentration limits that
can be used as decommissioning criteria for the eventual reclamation of the Mill. The Mill is a
uranium recovery facility. Therefore the relevant radionuclides are the primary radionuclides in
the uranium chain. As a result, reference soil concentration limits were developed for natural
uranium (U-nat) and Th-230. In addition, as described later, the dose from Pb-210 is included in
the dose assigned to Ra-226. These are the primary uranium radionuclides and the radionuclides
350496-009
15 August 2012
Letter to J. Tischler (Continued) Page 2

included in the Mill’s occupational and environmental monitoring programs. They are therefore
the radionuclides of concern for final decommissioning of the facility.1

The soil concentration limits for radionuclides other than Ra-226 are derived from doses
calculated for Ra-226 at 5/15 using the same exposure scenarios as were used to estimate the
dose from Ra-226 at 5/15. This is referred to as the radium benchmark dose (RBD). The RBD
approach was applied following the guidance used by the NRC staff in evaluation of the RBD
(Appendix H of NUREG-1620 (NRC 2003)).

Argonne National Laboratories (ANL) developed the RESRAD family of codes for the modeling
of dose as a result of residual radioactivity. The approach defined in this report utilizes the main
RESRAD code, Version 6.5. RESRAD is used by the Department of Energy (DOE),
Environmental Protection Agency (EPA), Army Corps of Engineers, and Nuclear Regulatory
Commission (NRC). Default dose conversion factors in the RESRAD code are derived from the
EPA’s Federal Guidance Report (FGR) Number 11 (EPA 1988). The RESRAD code calculates
effective dose equivalents from external radiation and committed dose equivalents (CEDE) from
internal exposures, providing a total effective dose equivalent (TEDE) (ANL 2001).

The RESRAD code is an accepted code by the NRC for application of the radium benchmark
approach as described in Guidance to the NRC Staff on the Radium Benchmark Dose Approach,
a document included in NUREG 1569 as Appendix E (NRC 2003).

Included in Appendix E of the User’s Manual for RESRAD Version 6 (ANL, 2001) are many
soil type / nuclide specific factors for integration into the water pathway analysis. Values were
drawn from this reference based on site-specific information regarding soil type and other site-
specific parameters as provided by Energy Fuels Resources (EFR).

The RESRAD (Version 6.5) code was used to implement the RBD approach as outlined below:

• The dose from Ra-226 in soil2 was estimated: RESRAD was used to estimate the dose
from Ra-226 from the surface (top 15 cm) and underlying (“subsurface”) soil (a 15 cm
layer under a 15 cm clean cover) separately. The Ra-226 concentration limit was 5 pCi/g
and 15 pCi/g incremental above background in the surface and subsurface soil layer
scenarios, respectively. The resulting dose in each layer is the RBD.
1 Natural thorium (Th-232) is found in conventional uranium ores and in some alternate feed materials. However,
the contribution of natural thorium at the site is considered to be minor, and any residual natural thorium is expected
to be cleaned up along with the primary uranium chain radionuclides. Th-232 is a strong gamma radiation emitter
and would be identified and reclaimed through any gamma radiation survey for Ra-226. Thus, Th-232 is not
considered further in the current analysis. 2 RESRAD calculates the ingrowth of Pb-210 from Ra-226 and adds the associated dose from Pb-210 to that of
Ra-226 itself. Since it is reasonable to expect Pb-210 to be present wherever Ra-226 is, the present analysis
assumes that at time=0, Pb-210 is present along with Ra-226, each at 5 pCi/g and 15 pCi/g in the surface and
subsurface soil layers respectively and that at all times, the dose assigned to Ra-226 is that due to Ra-226 +
Pb-210.
350496-009
15 August 2012
Letter to J. Tischler (Continued) Page 3

• The dose from the other radionuclides in the soil was estimated: RESRAD was used to
estimate the dose for U-nat, and Th-230, separately in the surface and subsurface soil
layer scenario for the same exposure pathways used to evaluate the RBD. A nominal
concentration of 100 pCi/g was used for each radionuclide and entered into RESRAD to
compute a dose.
• Scaling of the RBD to radionuclide concentrations: The dose from 100 pCi/g of each
radionuclide in the soil was scaled to the RBD to determine the incremental concentration
of each radionuclide, U-nat or Th-230, in soil that would result in the same dose as
5 pCi/g Ra-226 in the surface soil layer scenario and 15 pCi/g Ra-226 in the subsurface
soil layer scenarios.

A calculation time of 1000 years was used as recommended by the NRC (2003).

Receptor Scenario

The scenario chosen to model the potential dose to the average member of the critical group from
residual radionuclides at the site reflects our judgement as to reasonable future land use. The
residential rancher scenario is appropriate because according to the Final Environmental
Statement (FES) (NRC 1979), the area immediately to the north of the mill site is suitable for
residential structures, but was believed to be used only for the grazing of meat animals (beef). It
was assumed that meat animals could be grazed along the northern site boundary and eaten by
the nearest actual residents. Dairy cows are not likely because the prospect of supporting daily
cattle is not credible, given the arid climate and the much larger feed requirements of dairy cattle
as opposed to beef cattle. The aquatic foods pathway was not modeled because it would be
unlikely that a pond in the contaminated area would provide a significant quantity of fish for the
resident’s diet (NRC 2003).

The residential rancher would likely spend a significant fraction of time during the year onsite
and eat many of the crops and livestock produced onsite.

Exposure pathways included external radiation, inhalation (not including radon), plant ingestion,
meat ingestion, soil ingestion and groundwater. For a residential rancher with an exposure
duration of 30 years, the RESRAD default dietary data which apply for an adult were used.

RESRAD Input

This Section provides input values of parameters that were altered from RESRAD default
parameters to reflect the conditions at the Mill site. Table 1 provides a list of the parameters and
reference for the corresponding input value. Justifications of the altered parameters are provided
below.

350496-009
15 August 2012
Letter to J. Tischler (Continued) Page 4

Table 1 Altered RESRAD Parameters
Input Window Parameter Units Value Reference
Contaminated Zone
Parameters length parallel to aquifer flow m 23 Naftz et al 2012
thickness of contaminated zone m 0.15 NRC 2003
Cover/Contaminated
Zone Hydrological Data cover erosion rate a m/y 0 Assumption
contaminated zone erosion rate m/y 0 Assumption
hydraulic conductivity m/y 227 Yu et al 2001
b parameter - 5.3 Yu et al 2001
evapotranspiration coefficient - 0.795 NRC 2003
wind speed m/s 3.36 Denison 2008
precipitation m/y 0.34 Denison 2008
irrigation rate - 0 NRC 2003
Saturated Zone
Hydrological Data hydraulic conductivity m/y 53.6 Yu et al 2001
effective porosity - 0.18 Hydro Geo Chem
2012
b parameter - 7.75 Yu et al 2001
Uncontaminated
Unsaturated Zone Data
(one layer)
thickness m 23 Naftz et al 2012
hydraulic conductivity3 m/y 53.6 Yu et al 2001
effective porosity - 0.18 Hydro Geo Chem
2012
b parameter - 7.75 Yu et al 2001
Occupancy Data inhalation rate m3/y 8,395 NRC 2003
indoor time fraction - 0.25 NRC 2003
outdoor time fraction - 0.5 NRC 2003
Ingestion: Dietary Data irrigation water fraction - 0 NRC 2003
aquatic food fraction - 0 NRC 2003
plant food fraction - 0.25 Assumption
Meat fraction - 1 Assumption
Ingestion: Non-Dietary
Data root depth - 0.3 NRC 2003
a) Used in the Subsurface Soil Layer Scenario only.

3 Titan 1994 reports hydraulic conductivity data for the Mill site almost all of which are lower, typically < 10 m/y,
than the value developed from RESRAD tables.
350496-009
15 August 2012
Letter to J. Tischler (Continued) Page 5

Contaminated Zone Parameters

Two aquifers are used by Ute Mountain Ute tribal members in the vicinity of the Mill. A
shallow, unconfined aquifer exists in the Dakota Sandstone and Burro Canyon Formation, which
extends to a depth of about 23 m. The water in this aquifer is the source of springs located on the
reservation south of the Mill (Naftz et al 2012). Therefore, the length parallel to the aquifer
(depth) was changed to 23 m. The contaminated zone is the 0.15 m layer.

Cover/Contaminated Zone Hydrological Data

The cover depth is entered as 0 m in the surface and 0.15 m in the subsurface soil layer scenario.
Contaminated zone hydraulic conductivity was set to 227 m/y and the contaminated zone b
parameter was set to 5.3. The Mill is located on Blanding silt-loam (4-5 inch A horizon)
(NRC 1979); the hydraulic conductivity and b parameter for silty-loam is provided in Table E.2
of Yu et al 2001.

The evapotranspiration coefficient was changed to 0.795 which is the average of the range of
0.6-0.99 for the semi-arid uranium recovery sites (NRC 2003). The average wind speed was
changed to 3.36 m/s and the precipitation was changed to 0.34 m/y (normal annual precipitation
of about 13.4 inches, Denison 2008). The climate in southeastern Utah is classified as dry to arid
continental; therefore the irrigation rate was changed to 0 (e.g., acceptable if irrigation water is
obtained from a river). The Recapture Reservoir4 is used to provide facility water for the mill
site and as an irrigation source for fields surrounding the town of Blanding (Naftz et al 2012).

Saturated Zone Hydrological Data

As described above, the soil has a 4-5 inch silt loam A horizon and a silt-loam to silty-clay-loam
B horizon (NRC 1979). The saturated zone hydraulic conductivity was set to 53.6 m/y and the
contaminated zone b parameter was set to 7.75. The hydraulic conductivity and b parameter for
silty-clay-loam is provided in Table E.2 of Yu et al 2001. The effective porosity used in the
model was 18% based on data reported in Hydro Geo Chem (2012).

Occupancy Data

The inhalation rate was changed to 8,395 m3/y, which is used for the activity assumed for the
rancher (NRC 2003). The indoor time fraction was changed to 0.25, and the outdoor time
fraction was changed to 0.5. It was assumed that the rancher spends the remaining 25% of
his/her time off-site, which is consistent with NRC (2003).

4 The Recapture Reservoir is an impoundment of an ephemeral stream on the south slope of the Abajo Mountains
(DEQ 2006).
350496-009
15 August 2012
Letter to J. Tischler (Continued) Page 6

Ingestion: Dietary Data

The contamination fractions of the rancher’s diet were altered to reflect the regional practices.
The water irrigation fraction was changed to 0 which assumes no irrigation. The aquatic food
fraction was changed to 0, as it would be unlikely that a pond in the contaminated area would
provide a significant quantity of fish for the resident’s diet (NRC 2003). The plant food fraction
was changed to 0.25; as the arid climate in the region is unlikely to support a home garden that
provides the entire plant-based fraction of a rancher’s diet. The meat fraction was changed to 1,
which assumes beef cattle raised on-site will be consumed by the rancher.

Ingestion: Non-Dietary

The root depth was changed to 0.3 m which is the value that is appropriate for vegetable gardens
(NRC 2003).

Erosion

The discussion of erosion in NUREG 1620 is focussed on design of erosion protection and
erosion protection covers, and related factors, applicable to disposal cells, which in our opinion
is not useful for the present discussion. The RBD for the surface layer differs very little for the
scenario with or without erosion, while the RBD for the subsurface layer with erosion is roughly
twice as high as that without erosion. For present purposes, the lower RBD assuming no erosion
has been adopted.

Dose Results

Surface Soil Layer Scenario

The doses from radionuclides for the surface soil layer scenario are shown in Table 2.

Table 2 Dose Results for the Surface Soil Layer Scenario
Radionuclide
Surface Soil Layer
Concentration (pCi/g)
Maximum Dose
(mrem/y)
Time of Maximum
Dose (y)
Ra-226 5 48.19 0.00E+00 ±
U-nat 100 8.84 0.00E+00 ±
Th-230 100 105.80 1.00E+03 ±

Subsurface Soil Layer Scenario

The doses from radionuclides for the subsurface soil layer scenario are shown in Table 3.

350496-009
15 August 2012
Letter to J. Tischler (Continued) Page 7

Table 3 Dose Results for the Subsurface Soil Layer Scenario
Radionuclide
Subsurface Soil Layer
Concentration (pCi/g)
Maximum Dose
(mrem/y)
Time of Maximum
Dose (y)
Ra-226 15 59.18 0.00E+00 ±
U-nat 100 2.04 0.00E+00 ±
Th-230 100 41.75 1.00E+03 ±

Application of the Radium Benchmark Dose

Surface Soil Layer Scenario

The RBD for the surface soil layer scenario of 48.19 mrem/y was used to scale the doses from
100 pCi/g of each radionuclide (U-nat and Th-230) to an unrestricted use concentration limit for
each radionuclide. Using the dose from 100 pCi/g of each radionuclide, the RBD was scaled to
determine the concentration limit of each radionuclide as illustrated below for U-nat:

The scaled incremental concentration limit (i.e., reference soil concentration criteria for
unrestricted use) was found to be 545 pCi/g in the surface layer. The scaled incremental
concentration limits for each radionuclide in the surface layer are shown in Table 4.

Table 4 Incremental Concentration Limits for Surface Soil Layer Scenario
Radionuclide
Surface Soil Layer
Concentration
(pCi/g)
Ra-226 5 a
U-nat 545
Th-230 46
a) Allowable Ra-226 concentration.

Subsurface Soil Layer Scenario

The RBD for the subsurface soil layer scenario of 59.18 mrem/y was used to scale the doses
from 100 pCi/g of each radionuclide (U-nat and Th-230) to unrestricted use concentration limits
for each radionuclide. Using the dose from 100 pCi/g of each radionuclide, the RBD was scaled
to determine the concentration limit of each radionuclide as illustrated below for U-nat:

350496-009
15 August 2012
Letter to J. Tischler (Continued) Page 8

The scaled incremental concentration (i.e., cleanup criteria for unrestricted use) was found to be
2908 pCi/g in the subsurface layer. The scaled incremental concentration limits for each
radionuclide in the subsurface layer are shown in Table 5.

Table 5 Incremental Concentration Limits for Subsurface Soil Layer Scenario
Radionuclide Subsurface Soil Layer Concentration
(pCi/g)
Ra-226 15 a
U-nat 2908
Th-230 142
a) Allowable Ra-226 concentration.

The Sum Rule

Since there is more than one radionuclide, the criteria for unrestricted use is applied using the
unity rule such that the RBD is never exceeded (i.e., the sum of the ratios for each radionuclide
incremental concentration present (above background) to the concentration limit will not exceed
"1") as required by 10 CFR Part 40, Appendix A, Criterion 6(6).

The concentration limits (Table 4 and Table 5 for the surface and subsurface layer, respectively)
were used in the sum rules. The concentration in the numerator is determined by subtracting the
local background from the total measured value following remediation.

For the surface soil scenario:

For the subsurface soil scenario:

The foregoing calculations were performed by my colleague Mr. Arnon Ho. Either of us would
be pleased to respond to any questions you may have.

Yours very truly,

SENES Consultants Limited

Douglas B. Chambers, Ph.D.
Vice President,
Director of Radioactivity and Risk Studies
350496-009
15 August 2012
Letter to J. Tischler (Continued) Page 9

References

Denison Mines (USA) Corporation 2008. Environmental Report In Support of Construction
Tailings Cell 4b White Mesa Uranium Mill Blanding, Utah. April.

Hydro Geo Chem, Inc. 2012. Revised Draft Site Hydrogeology and Estimation of Groundwater
Travel Times in the Perched Zone White Mesa Uranium Mill Site near Blanding, Utah.
Prepared for Denison Mines (USA) Corp. Project Number 7180000.00-02.0. July 10.

Kirby, S. 2008. Geologic and Hydrologic Characterization of the Dakota-Burro Canyon Aquifer
Near Blanding, San Juan County, Utah.

Naftz, D., Ranalli, A.J., Rowland, R.C., and Marston, T.M. 2012. Assessment of Potential
Migration of Radionuclides and Trace Elements from the White Mesa Uranium Mill to
the Ute Mountain Ute Reservation and Surrounding Areas, Southeastern Utah.

Titan Environmental Corporation 1994. Hydrogeologic Evaluation of White Mesa Uranium Mill
Prepared for Energy Fuels Nuclear Inc., July.

United States Nuclear Regulatory Commission (NRC) 2003. Standard Review Plan for the
Review of a Reclamation Plan for Mill Tailings Sites Under Title II of the Uranium Mill
Tailings Radiation Control Act of 1978 Final Report. NUREG-1620, Rev.1. June.

United States Nuclear Regulatory Commission (NRC) 1979. Environmental Statement related to
operation of White Mesa Uranium Project Energy Fuels Nuclear, Inc. NUREG-0655.
May.

Utah Department of Environmental Quality (DEQ) 2006. Recapture Lake. August.

Yu, C., Zielen, A.J., Cheng, J-J, Le Poire, D.J., Gnanapragasam, E., Kamboj, S., Arnish, J.,
Wallo III, A., Williams, W.A., and Peterson, H., 2001. User’s Manual for RESRAD
Version 6. ANL/EAD-4. July.