DRC-2010-007888 - 0901a0688036114d

3/27/13 State of Utah Mail - Fwd: Denison Mines: Reclamation Ran, Revision 4.0 - Round 11nterrogatory
Sorja Robinson <sdrobuis^nCa)ytali.go¥>
Fwd: Denison Mines: Reclamation Pian, Revision 4.0 - Round 1 Interrogatory
Loren Morton <LMORTON(gutah.gov> Mon, Nov 1, 2010 at 2:27 PM
To: Sonja Robinson <[e-mail]>
Sonja,
Can you please see that this email I wrote to DUSA, and Its attachment (from URS) gets scanned into E-Docs?
rve also attached a "Green Sheet" to help.
Thanks,
Loren
Fonvarded message
From: "Loren Morton"
Date: Mon, 13 Sep 2010 14:35:30 -0600
Subject: Denison Mines: Reclamation Plan, Revision 4.0 - Round 1 Intenrogatory
To: "Harold Roberts"
Cc: "David Frydenlund", "Jo Ann Tischler , "Jon Luellen", "Bob Baird", "Dave Rupp", "John Hultquist", "Ryan
Johnson", "Rusty Lundberg"
Harold,
J
URS has finished its review of your 11/25/09 Reclamation Plan, Revision 4.0, and the Round 1 Interrogatory they
prepared for us is attached (WORD file). Please review the Interrogatory and revise the Reclamation Plan to
address and resolve all the issues listed and identfied.
In general there are 8 general issues that need to be addressed and resolved. Briefly these are (see Attached
Round 1 Interrogatory, p.2):
Interrogatory White IVIesa RecPlan 01/01: Includes concems related to handling and disposal of
asbestos-containing material, if present, and of (other) nonradiological hazardous constituents present.
Interrogatory White IVIesa RecPIan 02/01: Includes questions about potential for long-term plant and
animal intrusbn into the cover system that coukl inpact the performance ofthe final cover system, including
the compacted radon barrier layer and buried tailings.
Interrogatory White IMesa RecPlan 03/01: Includes several issues, questions and concem regarding:
- Plant and animal intrusion;
- Tailings and evaporation ceDs
- MiQ decommissioning
- Cover design and monitoring
- Erosion protection
- Rock quality
https://mail.google.conYmail/u/0/?ui=2&ihFe296e061df&Mevv=pt&search=inbo)4^^ 1/2
3^27/13 State of Utah Mail - Fwd: Denison Mines: Reclamation Ran, Rewsion 4.0 - Round 11nterrogatory
- Filter design
- Discharge channel and sedimentation basin
- Slope stability anatysis
Interrogatory White Mesa RecPlan 04/01: Incbdes need for additional information
regarding determinations or estimates of radon flux
Interrogatory White IVIesa RecPlan 05/01: Includes need for revision and e?q)ansion ofthe Quality Plan
for Construction Activities
Interrogatory White IVIesa RecPlan 06/01: Includes request to provide a Preliminary Decommissioning
Plan and Cost Estimates for reclamation and decommissioning. One new element listed here is the need for
stochastic modeling to predict range of fiiture costs for chamap and remediation ofthe groundwater
chloroform plume at the feciKty.
Interrogatory Wliite Mesa RecPlan 07/01: Includes need for additional information on Denison's
proposed approach to demonstrating the eflfectiveness of the proposed final radon barrier.
Interrogatory White Mesa RecPlan 08/01: Includes need for modifications to tiie radiation protection
program necessary to protect site workers, tiie public, and tiie environmental from any unique radiation hazards
and effects associated with reclamation and decommissioning activities.
We suggest that after you have an opportunity to review tiie Round 1 Interrogatory (attached), that we hold a
face-to-face meeting here in Salt Lake, or conduct a conference call to discuss its content, tfie patii forward, and
a schedule that will allow us to start a public comment period for a renewed License. This meeting or call would
incluse several DUSA, DRC, and URS staff and our new director. Rusty Lundberg.
Because Rust/s schedule fills up quickly, I suggest tiiat you call Rusty (801-536-4257) or myself sometime tills
week to schedule the face-to-face meeting or conference call.
If you have any otiier questions, feel free to call me (801-536-4262)
Loren '
2 attachments
ReclPlanR4lntRnd1 Final 100910.doc
^ 341K
m DUSA.doc
^ 56K
https://mail.googl0.conrVmail/u/Qri^ji=2&ik=e296eO61df&Mew=pt&sear^ 2/2
Denison Mines (USA) Corp - Rev. 4.0 Reclamation Plan Round 1 Interrogatories
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UTAH DIVISION OF RADIATION CONTROL
DENISON MINES (USA) CORPORATION
RECLAMATION PLAN, REVISION 4.0, NOVEMBER 2009;

INTERROGATORIES – ROUND 1
SEPTEMBER 2010
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TABLE OF CONTENTS
INTRODUCTION .......................................................................................................................... 1
SYNOPSIS OF INTERROGATORIES ......................................................................................... 2
INTERROGATORY White Mesa RecPlan 01/01: 10 CFR Part 40, Appendix A, Criterion 6(7);
UAC R313-24-3; Environmental Analysis – Long Term Impacts ................................................... 3
INTERROGATORY White Mesa RecPlan 02/01: 10CFR40 Appendix A, Criterion 1: Permanent
Isolation without Ongoing Maintenance ......................................................................................... 6
INTERROGATORY White Mesa RecPlan 03/01: 10CFR40, Appendix A, Criterion 4: Location and Design Requirements ............................................................................................................. 10
INTERROGATORY White Mesa RecPlan 04/01: 10CFR40, Appendix A, Criterion 6(1): Cover
and Closure at End of MIlling Operations .................................................................................... 26
INTERROGATORY White Mesa RecPlan 05/01: 10 CFR PART 40, Appendix A; UAC R317-
3-1; and UAC R317-3: Construction Quality Control and Assurance ......................................... 28
INTERROGATORY White Mesa RecPlan 06/01: 10CFR40, Appendix A, Criterion 9: Financial
Surety Arrangements .................................................................................................................... 34
INTERROGATORY White Mesa RecPlan 07/01: 11e.(2); 10CFR40, Appendix A, Criterion
6(2); 6(3); 6(4): Verify Effectiveness of Final Radon Barrier, and Phased Emplacement of Final
Radon Barrier, and Report Radon Barrier Effectiveness .............................................................. 41
INTERROGATORY White Mesa RecPlan 08/01: UAC R313-15-101; Radiation Safety Controls
and Monitoring.............................................................................................................................. 44

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ACRONYMS AND ABBREVIATIONS
ACM asbestos-containing materials
CFR Code of Federal Regulations
DG Draft Guide (NRC)
DOE U.S. Department of Energy
DUSA Denison Mines (USA) Corporation
EPA U.S. Environmental Protection Agency
FLAC Fast Lagrangian Analysis of Continuum
HGA horizontal ground acceleration
ICTM Infiltration and Contaminant Transport Modeling
NRC U.S. Nuclear Regulatory Commission
pCi picocurie; 10-12 curie
PGA peak ground acceleration
rem Roentgen Equivalent Man
RG Regulatory Guide (NRC)
SX solvent extraction
UAC Utah Administrative Code
5h:1v five horizontal units (5h) to one vertical unit (1v); represents slope or
steepness
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INTRODUCTION
The Utah Division of Radiation Control (the Division) is reviewing the license renewal
application submitted by Denison Mines (USA) Corp. (Denison) for its White Mesa uranium
mill. The Division has mobilized the expertise of URS Corporation (URS) by authorizing the
latter to review Revision 4 of Denison’s Reclamation Plan, submitted in connection with the license renewal application and to prepare interrogatories that solicit information the Division
judges is necessary to satisfy relevant regulatory requirements. The scope of this review is
limited strictly to matters relating to the design presently authorized by previous licensing
actions of the US Nuclear Regulatory Commission and the Division.
The Division instructed URS to consider interrogatories the Division had previously prepared and transmitted to Denison and related information submitted in response. The Division also
instructed URS to solicit information in sufficient detail to allow the Division to conduct an
effective inspection program at such time as the Reclamation Plan might be implemented.
Having reviewed Revision 4.0 of Denison’s White Mesa Reclamation Plan, URS prepared the interrogatories contained in this document. In developing these interrogatories, URS first prepared draft interrogatories which the Division then critically reviewed and to which the
Division has requested revisions. URS has responded to the Division’s requests and the Division
has accepted these interrogatories with intent to transmit them to Denison in order that the
Reclamation Plan that results from responding to these interrogatories will satisfy applicable regulatory requirements.
The Division (through URS) will review Denison’s responses to these interrogatories.
Additional rounds of interrogatories will be prepared and reviewed as necessary to ensure that
the Reclamation Plan ultimately satisfies applicable regulatory requirements. Once the
Reclamation Plan is acceptable to the Division, URS will prepare a technical memorandum documenting the conclusions of its review and Denison’s responses.
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SYNOPSIS OF INTERROGATORIES
The substance of the interrogatories that comprise this request for additional information is
summarized below.
Interrogatory White Mesa RecPlan 01/01: This interrogatory addresses the handling and
disposal of asbestos-containing material, if present, and of (other) nonradiological hazardous constituents present.
Interrogatory White Mesa RecPlan 02/01: This interrogatory addresses the potential for long-
term plant and animal intrusion into the cover system that could impact the performance of the
final cover system, including the compacted radon barrier layer and buried tailings.
Interrogatory White Mesa RecPlan 03/01: This interrogatory addresses:
• Plant and animal intrusion
• Tailings and evaporation cells
• Mill decommissioning
• Cover design and monitoring
• Erosion protection
• Rock quality
• Filter design
• Discharge channel and sedimentation basin
• Slope stability analysis
Interrogatory White Mesa RecPlan 04/01: This interrogatory addresses the previous
determinations or estimates of radon flux
Interrogatory White Mesa RecPlan 05/01: This interrogatory addresses the revision and
expansion of the Quality Plan for Construction Activities
Interrogatory White Mesa RecPlan 06/01: This interrogatory addresses the request to provide a Preliminary Decommissioning Plan and Cost Estimates for reclamation and decommissioning.
Interrogatory White Mesa RecPlan 07/01
This interrogatory addresses Denison’s proposed approach to demonstrating the effectiveness of
the proposed final radon barrier.
Interrogatory White Mesa RecPlan 08/01: This interrogatory addresses modifications to the radiation protection program necessary to protect site workers, the public, and the environmental
from any unique radiation hazards and effects associated with reclamation and decommissioning
activities.
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INTERROGATORY WHITE MESA RECPLAN 01/01: 10 CFR PART 40, APPENDIX A, CRITERION 6(7); UAC R313-24-3; ENVIRONMENTAL ANALYSIS – LONG TERM IMPACTS
REGULATORY BASIS:
UAC R313-24-3:
(1) Each new license application, renewal, or major amendment shall contain an environmental
report describing the proposed action, a statement of its purposes, and the environment affected. The environmental report shall present a discussion of the following:
“(a) An assessment of the radiological and nonradiological impacts to the public health
from the activities to be conducted pursuant to the license or amendment;…
(d) Consideration of the long-term impacts including decommissioning, decontamination,
and reclamation impacts, associated with activities to be conducted pursuant to the license or amendment…”
UAC R313-24-4 invokes the following requirement from 10CFR40, Appendix A, Criterion 6(7):
“The licensee shall also address the nonradiological hazards associated with the wastes in
planning and implementing closure. The licensee shall ensure that disposal areas are closed in a
manner that minimizes the need for further maintenance. To the extent necessary to prevent threats to human health and the environment, the licensee shall control, minimize, or eliminate post-closure escape of nonradiological hazardous constituents, leachate, contaminated
rainwater, or waste decomposition products to the ground or surface waters or to the
atmosphere.”
INTERROGATORY STATEMENT:
Refer to Sections 2.2 and 3 of the Reclamation Plan, Rev. 4.0:
1. Handling and Disposal of Asbestos-Containing Material, if Present: Please identify the
characteristics, nature of occurrence, and quantity(ies) of any asbestos-containing
materials (ACM) , such as friable asbestos or other ACM, transit pipe, etc., that could be
encountered during reclamation/decommissioning activities.
If ACM are known or suspected to be encountered during decommissioning, please prepare and submit an Asbestos Characterization, Removal, Handling and Disposal Plan
for implementation prior to and/or during site demolition and site reclamation activities.
Indicate regulatory criteria and statutes applicable to such materials. Provide information
on, and the location of records important to decommissioning procedures for any ACM, as applicable, for protection of health and safety.
Provide procedures for demonstrating that asbestos handling and disposal activities and
practices will be completed in accordance with all applicable state and Federal
requirements, including, but not limited to (1) Utah Solid and Hazardous Waste Control
Board, Utah Solid Waste Permitting and Management Rules (Utah Division of Solid and Hazardous Waste 2009, or latest version); and (2) Utah Air Quality Rules (Utah Division of Air Quality 2010, or latest version).
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2. Handling and Disposal of (Other) Nonradiological Hazardous Constituents Present: Please identify the characteristics, nature of occurrence, and quantity(ies) of other non-
radiological hazardous constituents present at the Mill Site that would be encountered during
reclamation/decommissioning activities. Include information on acid leach solutions (e.g.,
associated with the seven acid leach tanks inside the Main Mill building) and solvent extraction (SX) reagents (see Reclamation Plan, Sections 2.2.2 and 3.1), and other non-
radiological and potential hazardous constituents present. Please prepare and submit
procedures for characterizing, handling, and treating and/or disposing of such non-
radiological hazardous constituents prior to and/or during site demolition and site reclamation activities. Indicate regulatory criteria and statutes applicable to such materials. Provide information on, and the location of records important to decommissioning
procedures for any such materials, as applicable, for protection of health and safety. Provide
procedures for demonstrating that handling and disposal activities and practices associated
with the management of these constituents will be completed in accordance with all applicable state and federal requirements.
BASIS FOR INTERROGATORY:
Facility-related hazardous chemicals and reagents are present in one or more structures at the White Mesa Mill Site. ACM might also be present in one or more structures at the Mill Site. Such materials should be handled and disposed of in strict accordance with applicable state and
federal requirements, in order to minimize potential impacts to workers and public health and the
environment. Additional information needs to be furnished regarding the location of records
important to decommissioning procedures for any non-radiological hazardous constituents, and ACM, as applicable, for ensuring protection of health and safety. All work related to characterization, removal, handling and disposal of such materials should be conducted in
accordance with applicable federal, state, and local air quality and solid waste disposal rules,
regulations and guidelines.
NUREG-1620 (NRC 2003), Section 5.2.3, indicates that the decommissioning plan will be acceptable if it meets the following criteria:
“…(7) The plan indicates the location of records important to decommissioning
procedures for protection of health and safety and demonstrates that decommissioning
will be completed as soon as practicable, as required by 10 CFR 40.42 and Appendix A,
Criterion 6A…”
“…9) The plan adequately describes the control of non-radiological hazards associated with the wastes as required by 10 CFR Part 40, Appendix A, Criterion 6(7).”
NRC Draft Guidance (DG) 3024 (NRC 2008), Section 8.1 specifies that license applicants
should provide the following with respect to reclamation/decommissioning projects:
“Provide the proposed plan for removing and disposing of structures, tanks, and equipment used in conjunction with the uranium milling operations, including the plan for managing all hazardous and radioactive materials. In the decommissioning plan,
consider approaches for identifying radiological hazards before initiating dismantlement
of structures and equipment and for detection and cleanup of removable contamination
from such structures and equipment in order to minimize occupational radiation
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exposure. Describe appropriate survey methods for determining the extent of equipment
contamination before initiating decontamination work. Focus, in particular, on those
parts of the mill process system that are likely to have accumulated contamination over
long time periods (e.g., pipes, ventilation, equipment, effluent control systems, and facilities and equipment used in or near the yellowcake dryer area). Describe any plans for the decontamination of equipment for release for unrestricted use…”
REFERENCES:
NRC (U.S. Nuclear Regulatory Commission). 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, May, 2008.
Utah Division of Air Quality. 2010. Utah Air Quality Rules. Effective June 3, 2010.
URL: http://www.airquality.utah.gov/Planning/Rules/Actual_Rules/current-rules.pdf.
Utah Division of Solid and Hazardous Waste. 2009. Utah Solid And Hazardous Waste Control Board, Utah Solid Waste Permitting and Management Rules Utah Administrative Code
(R315-301 Through 320). Revised as of May 15, 2009. URL:
http://www.hazardouswaste.utah.gov/Rules/Adobe/SWRules/R315-301-320eff.pdf.
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INTERROGATORY WHITE MESA RECPLAN 02/01: 10CFR40 APPENDIX A,
CRITERION 1: PERMANENT ISOLATION WITHOUT ONGOING MAINTENANCE
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.”
INTERROGATORY STATEMENT:
1. Refer to Section 3.3.7 of the Reclamation Plan:
a. Please evaluate and report the potential for long-term plant intrusion and animal intrusion into the cover system that could impact the performance of the final cover system, including the compacted radon barrier layer and buried tailings, assuming
minimal to no long-term maintenance following decommissioning.
b. Please provide a description of plant root characteristics (e.g., root depths, root
distribution, leaf area index) of plant species that are currently present or could be expected to be present in the future at the site
c. Please describe and estimate the range of burrowing depths and burrow densities for
animal species that presently frequent or could be expected to frequent the site or
the site vicinity
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d. Please provide information on the required characteristics of a biobarrier layer, such
as a cobble layer (e.g., required particle size distribution and minimum required
thickness); and the need for, and design requirements relating to any adjacent filter
layer(s) that would be incorporated into the final cover system to minimize or
prevent potential burrowing animals and root growth from penetrating the cover, including the radon barrier layer and/or buried cell tailings. Include information
justifying that the final specified characteristics of the biobarrier layer would be
adequate to deter long-term biointrusion into the radon barrier layer, considering
available published information on biontrusion cases studies (e.g. Hakonson 1986; Cline et al. 1980, etc…). Alternatively, provide detailed information that clearly demonstrates why such a biobarrier is not warranted or necessary:
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 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 protect the cover system, especially the radon
barrier layer, from potential long-term damage/disruption by burrowing animals.
Plants growing into the cover could root into the radon barrier layer and/or into tailings. Penetrating roots could provide channels for water movement and may cause shrinking or
cracking of clay layers (Reynolds 1990). At arid and semi-arid sites, root densities can be higher
in buried clays and plant roots may concentrate in and extract water from buried clays and plant
roots may concentrated in and extract water from buried clay layers, causing some seasonal desiccation (Hakonson 1986 and Reynolds 1990a). The degree of root penetration depends on the rooting depth of the plants present at the site or in the site vicinity and the ability of the plant
roots to penetrate the soil.
Hakonson(1986) found that a biotic barrier of 28 inches composed of cobbles (of diameter to
inches) overlain by 12 inches of gravel was an effective deterrent to burrowing by gophers and mice and that the large void spaces between the cobbles deterred plant root development. Cline et al. (1980) and Cline (1979) found a layer of cobblestone to be effective in limiting rodent and
insect penetration. Final selection of the minimum layer thickness and rock sizing in the
biobarrier should be based on site-specific conditions and characteristics (e.g., types of animals
and plants that are or might be present in the area over the design life of the closed embankment).
According to the Revision 4 Reclamation Plan (e.g., Table 1.7-1), 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
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exhibit rooting depths between about 114 and 250 cm [between about 3.7 and 8 ft] and possibly
up to 914 cm [30 ft] (e.g., see Waugh, et al. 1994; Foxx, et al.1984; Klepper, et al. 1985,
Reynolds 1990b). The Reclamation Plan, Rev. 4 also indicates (Section 1.7.1.2) that badgers,
longtail weasels, and several rodents (e.g., deer mouse) exist in the area.
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.
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. Williams., 1984. Rooting Depths of Plants Relative to
Biological and Environmental Factors, Los Alamos Report LA-10254-MS, November 1984.
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.
Klepper, E. L., K. A. Gano, and L. L. Cadwell. 1985. Rooting Depth and Distributions of Deep-Rooted Plants in the 200 Area Control Zone of the Hanford Site, PNL-5247, Battelle Pacific Northwest Laboratory, Richland, Washington.
Lindzey, F. G. 1976. “Characteristics of the Natal Den of the Badger,” Northwest Science, Vol.
50, No. 3, pp. 178–180.
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.
Reynolds, T.D. 1990a. “Effectiveness of Three Natural Biobarriers in Reducing Root Intrusion
by Four Semi-Arid Plant Species”, Health Physics, Vol. 59, pp. 849–852.
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Reynolds, T. D, 1990b. “Root Mass and Vertical Root Distribution of Five Semiarid Plant
Species,” Health Physics, Vol. 58, No. 2, pp. 191–197.
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.
Waugh, W. J., J C. Charters, G. V. Last, B. N. Bjornstad, S. O. Link, C. R. Hunter, 1994. Barrier
Analogs: Long-Term Performance Issues, Preliminary Studies, and Recommendations,
PNL-9004, Pacific Northwest Laboratories, Richland, Washington.
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INTERROGATORY WHITE MESA RECPLAN 03/01: 10CFR40, APPENDIX A,
CRITERION 4: LOCATION AND DESIGN 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.
(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 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,
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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.
(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.
(f) The impoundment, where feasible, should be designed to incorporate features which will promote deposition. For example, design features which promote deposition of sediment
suspended in any runoff which flows into the impoundment area might be utilized; the object of
such a design feature would be to enhance the thickness of cover over time.”
INTERROGATORY STATEMENT:
1. Soil Cover-Plant and Animal Intrusion (Refer to Reclamation Plan, Rev. 4.0, Section 3.3):
a. Please provide information on the design and required characteristics of a
biobarrier system required in the final cover system to prevent long-term intrusion
into the radon barrier layer by burrowing animals or plants after closure, in accordance with Interrogatory Item No. 1 under Interrogatory WhiteMesa RecPlan 02/01: 10CFR40 Appendix A, Criterion 1: “Permanent Isolation without Ongoing
Maintenance” above.
2. Tailings and Evaporation Cells (Refer to Sections 3.2.2.1, 3.2.2.3, 3.2.2.4, and 3.2.2.5
and Figure 5.1-1 in Attachment A of the Reclamation Plan, Rev. 4.0):
a. Please revise (steepen) the slope of the top deck portion of the final cover system to ensure that an adequate factor of safety is provided to ensure long-term stability of
the completed embankment(s) considering the potential for future slope reversal(s)
due to long-term differential settlement or subsidence, in accordance with guidance
contained in 10CFR 40, Appendix A, Technical Criterion 4; to be consistent with published recommended ranges of slopes for final cover systems for uranium mill tailings repositories, surface impoundments, and landfills – i.e., approximately 2%
to 5% (e.g., see DOE 1989; EPA 1989; EPA 1991, ITRC 2003, and EPA 2004); and
to ensure that the topslope portion of the embankment surface will exhibit a slope
across the entire embankment; after settlement/subsidence, that is adequate to promote lateral runoff of precipitation without ponding..
3. Mill Decommissioning (Refer to Section 3.2.3.1 and Sections 4.0 through 4.3 of Attachment A of the Reclamation Plan, Rev. 4.0):
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a. Please specify a maximum allowable void space percentage that will be allowed
when disposing of demolition and decommissioning debris and rubble in tailings
cells. Describe construction practices that will enable satisfying this specified limit.
b. Please provide additional information on specific procedures that will be used for
placement, backfilling, and compaction of debris and rubble generated by demolition and decommissioning activities. Address differences necessary to ensure
specified limits are achieved for metallic structural components, pipe and pipe
sections, wood debris, concrete rubble, and large rock fragments within the
embankment. Describe in detail methods that will be used to reduce the size of debris and rubble items before being blended with tailings or contaminated soils. Describe procedures for compacting each type of debris or rubble mixed with
tailings or contaminated soil. Include maximum allowable lift thickness and
maximum allowable dimensions for each type of debris or rubble to be disposed of.
c. Please include specifications, constraints, and procedures for constructing the final waste layer upon which the cover system (final closure cap) will be constructed. Demonstrate that these specifications, constraints, and procedures are adequate to
preserve the integrity and stability of the cover system.
d. Please define the characteristics and volumes of organic materials (including, for
example, wood, branches, roots, paper, and plastic), if any, that might 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.
e. 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 construction quality assurance / quality control and verification procedures to be used to demonstrate that the void space criteria are achieved.
f. Please provide an Asbestos Characterization, Removal, Handling and Disposal Plan
for implementation prior to and/or during site demolition and site reclamation
activities for any ACM (e.g., friable, transit pipe) that may be encountered during reclamation activities (see also Interrogatory WhiteMesa RecPlan 01/01 above).
4. Cover Design and Monitoring (Refer to Reclamation Plan, Rev. 4.0, Sections 3.2.2.1 and 3.3 and Section 5.4 of Attachment A):
a. Please describe quantitative acceptance criteria that will be used as the basis for
evaluating stability of the closed tailings cells in terms of potential long-term total and differential settlement or subsidence that might occur within the closed embankments or tailings cells. Provide information on parameters that could affect
the long-term integrity of the final closure cap and/or could affect long-term
infiltration rates through the closed embankment, including, but not necessarily
limited to:
• The potential for (e.g., localized) slope changes and slope reversal in the final cap.
• The potential for cracking of the compacted clay layer (radon barrier layer).
Provide information regarding the relationship of the selected acceptance criteria
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for assessing cracking potential in the compacted clay layer (e.g., a specified
maximum allowable tensile stress in clay) to the percent tensile strains in the
compacted clay layer and the range of plasticity indices for the proposed clay
layer source materials (see, for example, Gilbert and Murphy 1987, Section 4;
Daniel 1993, pp. 472–474; Koerner and Daniel 1994) as they relate to and support the final selected cover design. Demonstrate that the proposed clay layer source
materials are suitable for minimizing potential long-term cracking within the
compacted clay layer to within an acceptable level.
b. Please provide engineering analyses (including calculations, numerical modeling and simulations) documenting the projected long-term settlement performance of the closed embankment for various scenarios involving disposal of tailings mixed
with demolition debris and/or rubble deemed reasonably representative of the range
of tailings/debris and rubble disposal configurations that could occur within the
embankment. Provide numerical analyses demonstrating settlement performance of the embankment using a software tool such as the Fast Lagrangian Analysis of
Continuum (FLAC®) code (Itasca 2009) or other similar software, as appropriate, or
alternatively, provide information justifying why such analyses are not warranted or
necessary. Compare and document predicted settlement/subsidence results against
the acceptance criteria identified stated in response to Item a. above.
5. Erosion Protection (Refer to Sections 3.2.2.2, 3.3.1, and 3.3.5; Section 6.0 and Figures A.5.1-1 through A-5.1.4 in Attachment A; and Attachment G to the Reclamation Plan, Rev. 4.0):
a. Please provide a clearly described, clearly referenced, up-to-date calculation of the
Probable Maximum Precipitation (PMP) Event to be used for final reclamation
design planning. Provide information demonstrating that the PMP Event was determined using approaches that are consistent with guidelines contained in
NUREG-1623 (NRC 2002).
b. Please provide information demonstrating that the riprap sizing proposed for all
topslope and sideslope areas is adequate for the updated PMP Event magnitude.
c. Please update Figures A.5.1-1 through A-5.1.4 in Attachment A to reference and reflect applicable updated information and updated erosion protection design
criteria as described in this interrogatory item. Please describe and clearly indicate
on the reclamation plan drawings, the location(s), minimum horizontal reach
length(s), and minimum thickness(es) of any toe rock apron(s) to be installed at the
toes of any final closed embankment slopes, including all cells (Cells 1 through 4B). Provide updated calculations necessary to justify the stone size required to
maintain (stabilize) the transition slope from the embankment sideslopes to
surrounding flatter terrain. Determine and justify the D50 particle size of rock used
in each such toe rock apron, the minimum horizontal reach, and minimum depth for
each such apron for the updated PMP Event and using an appropriate methods as described in the following reference documents:
• NRC 2002
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• NRC 2003 (Section 3)
• Robinson, et al. 1998; and
• Apt, et al. 2008 (if round-shaped riprap is used in instances where overtopping
flow could occur).
d. Provide information on the shape characteristics of rock (stones) to be used in any rock toe aprons (e.g., angular vs. rounded stones).
e. Please verify and justify how the minimum horizontal reach (7.0 ft) and the
minimum depth (2.0 ft) for the rock apron depicted on Figure A-5.1-4 are adequate,
when the methodologies identified above are considered.
f. For any areas adjacent to disposal Cells 1 through 4B where a toe rock apron is not proposed to be installed, provide information to clearly demonstrate that the
absence of such will not compromise long-term erosion protection of the closed
tailings cells.
6. Rock Quality (Refer to Section 3.3.5 of the Reclamation Plan [Rev. 4.0], and Section
6.0 and Figure A-5.1-4 of Attachment A and Attachment H to the Reclamation Plan [Rev. 4.0]) [Note: This interrogatory item was previously provided to DUSA in January
2010 as part of the Round 2 Interrogatories submitted on the Cell 4B Environmental
Report]:
a. Please include information as appropriate to reflect updated criteria contained in NUREG-1623 (NRC 2002) regarding acceptability of rock, based on its rock quality score, for use in areas that the NRC may classify as “frequently saturated
areas,” including rock toe apron areas at the toes of the closed cell outslopes, to be
addressed in the final closure design. Specifically, indicate that rock from the
Brown Canyon Site borrow site would be rejected (based on the NUREG-1623 rock scoring criteria) from use in the rock toe apron areas at the base of the toes of cell outslopes in the final closure design. Please verify and provide information to
demonstrate that adequate quantities of acceptable rock (based on the NUREG-
1623 guidance) for completing required final reclamation activities at the White
Mesa Mill Site are available from other borrow sources.
7. Filter Design (Refer to Sections 3.2.2.1, 3.3, 3.3.5; Sections 2.5, 5, and 6 in Attachment A; and Figures A.5.1-2, through A.5.1-4 in Attachment A of the Reclamation Plan [Rev. 4.0]):
a. Please evaluate/demonstrate the need for incorporating a filter layer/filter blanket or
granular bedding layer(s) (1) in the final cover system; (2) beneath riprap at proposed toe rock apron locations, at flow transition areas; (3) in diversion ditches/channels; (4) in the Cell 1 area sedimentation basin, and (5) at other
potential flow impact areas. Please revise the Revision 4 Reclamation Plan design
document and drawings as required to address the inclusion of any such layers
demonstrated to be necessary for long-term stability. Provide calculations confirming the required gradations for materials used in each such filter/bedding layer in accordance with applicable filter design criteria (e.g., as described in
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NUREG-1623). Alternatively, provide detailed information that would clearly
justify why filter/bedding layers are not required at these locations.
8. Discharge Channel and Sedimentation Basin (Refer to the Reclamation Plan,
Revision 4.0 , Section 2.5, Attachment A, and Figure A-2.2.4-1):
a. Please clearly identify on Figure A-2.2.4-1 the topographic contours for all portions of the proposed Cell 1 discharge channel and the surrounding terrain, and clearly
identify the slope (s) of the channel sides. Please verify and revise the dimensions
of the Cell 1 discharge channel shown on the figure as needed to correspond to
dimensions of the channel selected in the final design, e.g., consistent with the final channel dimensions used in design calculations for the channel and toe apron (e.g., Attachment G of the Reclamation Plan).
b. Please provide detailed information, including a geologic map with cross sections
as appropriate, showing subgrade conditions (e.g., weathered vs. unweathered
soils/colluvium, weathered vs. unweathered bedrock of the Dakota Sandstone (and/or Mancos Shale), fractured vs. unfractured Dakota (and/or Mancos Shale) bedrock, presence and distribution of conglomeratic lenses, etc.) that would occur
along the entire reach of the proposed channel (i.e., those that might affect both the
channel sideslopes and channel bottom).
c. Please provide information justifying the discharge channel parameter values used in calculations of discharge channel flow rates presented in Attachment G of the Reclamation Plan. Please provide a clearly referenced calculation along with clearly
referenced methods to support the selection of an appropriate Manning ‘n’
coefficient or range of Manning ‘n’ coefficients for the discharge channel subgrade
conditions, reflecting the variability of those conditions, as appropriate, along the channel reach. Please also provide an engineering analysis and/or other information justifying and supporting the proposed allowable peak channel velocity of 8–10 fps,
assuming bedrock material, when compared to published recommended (lower)
allowable peak velocity ranges for bedrock materials (e.g., Nelson, et al. 1986).
Please also include a clearly referenced calculation of the PMP-derived flow rate.
d. Please provide additional information regarding the design of the sedimentation basin and associated outlet channel, including information assessing design issues
that are pertinent to the design of riprap basin and apron systems (see, for example,
U.S. Department of Transportation - Federal Highway Administration 2006,
Chapter 10):
• The need for armoring of the apron at the basin/discharge channel connection;
• The estimated depth of scour that would occur in a thick pad of riprap and
selection of the sedimentation basin floor depth based on the scour depth;
• The need to include an energy dissipating pool in the basin/channel system
design. Include dimensions and drawings of the dissipating pool, discharge channel, and apron;
• The minimum D50 and thickness of a riprap layer lining the bottom of the
sedimentation basin;
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• Riprap type, rounded rock and/or angular rock. Include minimum specifications
for the riprap, including but not limited to: lithology, material type, rock hardness,
sodium absorption ratio, LA abrasion test results, etc. as per the guidelines
contained in NUREG-1623 (NRC 2002).
• Riprap cutoff wall or sloping apron as needed if long-term downstream channel degradation is anticipated;
• Specify design input/criteria and design procedure used for sizing and selecting
dissipating pool, discharge channel, and apron;
• Other pertinent factors that may relate to the design.
Please also provide information on the need for including one or more filter layers/filter blankets within the basin/channel system, in accordance with the
guidance presented in paragraph 2.1.1, Filter Requirements, of Appendix D,
Designing Riprap Erosion Protection, of NUREG-1623 (NRC 2002).
e. Provide revised sedimentation basin and drainage channel drawings as required to address/resolve the issues identified above in the Reclamation Plan, Rev. 4.0.
f. Please provide the basis for allowing the channel to be constructed of bedrock and
not specifying riprap for the channel.

9. Slope Stability Analysis (Refer to Section 3.3.6 of the Reclamation Plan, Rev. 4.0):
a. Please revise and update the information in Section 3.3.6 to:
• Include and/or clearly reference the updated seismic hazard evaluation (Tetra
Tech 2010) that was completed for the White Mesa Mill Site, and describe the
effects of the results of that evaluation on slope stability analyses.
• Provide updated static and seismic (e.g., pseudostatic) stability analyses for appropriately selected (e.g., most critical) slopes for the final cover design once it is selected for implementation.
BASIS FOR INTERROGATORY:
It is understood that a new design for a final cover system for the tailings cells is currently in
development and that such a design will be reviewed and approved in accordance with DRC’s review of the Infiltration and Contaminant Transport Modeling (ICTM) study at a future date. Any changes found necessary as a result of this work may be incorporated in a future version of
the Reclamation Plan.
Nonetheless, it is important that the current subject, i.e. the review of this separate final cover
system design, address all issues that could affect its long-term performance. Issues described below under this interrogatory heading, and described in other interrogatories included in this set of interrogatories, must also be adequately addressed and included in the revision to the
Reclamation Plan, Rev. 4.0 (DUSA 2009a).
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The “Basis for Interrogatory” discussion presented under Interrogatory WhiteMesa RecPlan
02/01: 10CFR40 Appendix A, Criterion 1: “Permanent Isolation without Ongoing Maintenance”
above, provides the basis/rationale for inclusion of Interrogatory Item No. 1 in this interrogatory.
The proposed cover slope (minimum of 0.2%) is very flat and likely to be problematic from the
standpoint of potential long-term 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 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:
“…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 slope (minimum of 0.2%) is much flatter than the above recommended
ranges of slope inclinations. The cover design should include a minimum embankment and topslope slope inclination that is consistent with the above guidelines, to ensure 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 the range of potential tailings and/or tailings and demolition debris disposal
conditions for the embankment. The final topslope inclination must ensure that the topslope portion of the embankment surface will exhibit a positive slope across the entire embankment; after settlement/subsidence, that will be adequate to promote lateral runoff of precipitation
without ponding, over the long-term.
According to Section 3.2.3.1 of the Reclamation Plan, Rev. 4.0, contaminated equipment,
structures and dry waste materials from Mill decommissioning, contaminated soils underlying the Mill areas, and ancillary contaminated materials “will be disposed of in tailings Cell 3, Cell 4A, or the Cell 1 Tailings Area.” [Note: Although not explicitly stated in the current Reclamation
Plan, it is presumed that it is DUSA’s intent that such items may also be disposed in tailings Cell
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4B.] The placement/disposal of demolition debris materials in the tailings management cell(s)
has the potential to create voids within disposed materials 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 cap could lead to unacceptable long-term
total or differential settlement in the reclaimed embankment. Excessive amounts of such settlement could impact the integrity of the final closure cap that could produce localized slope
change(s) and/or slope reversal(s) in the final slopes of the reclaimed embankment. A slope
reversal would create an opportunity for localized ponding of moisture or water that could
increase infiltration rates through the embankment cap. Different materials derived from the demolition of on-site buildings and/or other structures that are planned for disposal on site beneath the final closure cap may have unique characteristics for unloading, placement, and
compaction. Proper disposal of demolition debris materials requires spreading such debris to
allow adequate coverage with contaminated soil and/or tailings that will allow proper
compaction of the soil/tailings around the placed debris items for support so that there is no reliance on the strength of debris for such support.
In order to provide confidence that the final cover system installed over any areas where
demolition debris materials are disposed will remain stable over the design life of the facility, the
following provisions should be assured:
• Specific procedures should be provided to define the processes that will be used for placing debris materials to ensure that such placement is conducted deliberately and is carefully controlled to prevent inclusion of voids within the waste matrix. This will
facilitate compaction of backfill around individual debris pieces.
• Specific procedures should be provided that define measures that will be taken for
reducing residual voids between individual pieces of debris. The procedures should ensure that backfilling and other methods obtain proper compaction throughout the embankment.
• Specific procedures should be provided that define the methods for placement of
debris within the embankment to ensure that pieces that could protrude into the final
cover system do not remain in a vertical orientation.
• A specific maximum allowable residual void space percentage within tailings/debris materials and/or contaminated soil/debris material mixtures in the disposal should be
prescribed.
Detailed procedures should be written that define specific methods for decommissioning and
demolition debris disposal that minimize residual void space within the Cell 1 embankment to be used for demolition disposal, including procedures for spreading the materials uniformly and/or backfilling void spaces, and that are designed to permit the prescribed maximum allowable void
space limit to be achieved. Metal waste materials should be placed in a tailings layer so that
structural shapes or other large pieces do not lie across or on top of each other. A procedure
should be developed indicating that metal placement would be conducted so that any large voids that cannot be filled with soil or crushed are minimized. Additionally, in some cases it may not be possible to reach the void spaces with standard earthwork placement, backfilling, and
compaction methods. The Reclamation Plan should address such cases, by providing a
discussion regarding the need for, and criteria for deciding when to implement another method or
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methods for filling the otherwise inaccessible void spaces. Such filling methods may include
injecting grout, controlled low strength material, or other proposed flowable substance into the
voids.
Special handling and disposal procedures for oversized and/or odd-shaped steel materials,
including procedures for placing any such materials to one side and cutting or trimming before positioning for burial, should be addressed. Oversized or odd-shaped materials include any metal
waste that cannot be placed within the specified lift thickness. A procedure should be developed
that indicates that placement and compaction of wood materials would include, at a minimum,
placement of pieces or stacks of such materials (e.g., bundles of siding or stacks of wood planks) within a specified maximum lift thickness. A procedure should be developed that limits the length and diameter of pipes that may be disposed on site beneath the final closure cover at a
specified minimum depth. It is anticipated that the procedure might require that all pipe (except
transit pipe, if encountered at the site) would be cut into lengths of approximately 10 feet or less,
and pipe larger than 12 inches in diameter would be longitudinally split or cut, while pipe less than 12 inches in diameter would not require splitting.
A procedure should also be developed that addresses the placement of concrete rubble and
larger-sized rock fragments, including procedures for placement and spreading these items into
contaminated soil or tailings material lifts that do not exceed a specified maximum thickness
(within a specified tolerance range), and for compacting the composite soil/tailings and rubble and/or rock layers using a specified minimum number of passes of heavy-tracked construction equipment. Applicable guidance documents and/or case studies exist where such specific
procedures have been successfully used at other tailings disposal repositories (e.g., DOE 1995;
DOE 2000; others) and where excessive amounts of post-closure settlement have not been
observed to occur following application of those procedures (e.g., see DOE 2009a, 2009b, 2009c; 2009d) have not been observed in tailings repositories where such debris placement, backfilling, and compaction procedures were employed.
Additionally, residual voids might result from biodegradation of any disposed organic matter
after final closure of the disposal cells. Procedures should be provided to define measures that
would be used to limit the amount of organic materials disposed of in any lift of the tailings embankment.
Specific, quantitative, acceptance criteria need to be defined for the final cover system design/
performance to serve as a basis for demonstrating the long-term stability of the final cover
system/closed embankment with respect to long-term settlement or subsidence. The effects of
settlement/subsidence on the long-term integrity of the embankment cover system through the closed embankment over its design life need to be evaluated.
Available published information should be used to estimate the maximum amount of
strain/maximum distortion value that could tolerated within the compacted clay radon barrier
layer over the design life of the reclaimed embankment. Such a limit should be based on
properties (e.g., range of plasticity indices) of the clay soils proposed for constructing the radon barrier layer. Engineering analyses should be provided for various representative disposal configurations involving disposed tailings and demolition debris/rubble materials to demonstrate
that predicted settlement/subsidence magnitudes and locations will not exceed specified
acceptance criteria for strain or distortion value. For example, the potential exists for a
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substantial quantity of demolition debris materials to be generated and disposed within the
tailings embankment (e.g., see Sections 3.1 and 3.2 of Attachment A and the Mill
Decommissioning calculations in Attachment C of the Reclamation Plan). Consideration should
therefore be given to conducting numerical model simulations for estimating long-term
settlement/subsidence performance for a suite of different representative assumed tailings/debris disposal configurations.
Information needs to be provided to confirm that the proposed clay layer source materials are
suitable for minimizing the potential for long-term cracking of the compacted clay layer or radon
barrier (e.g., for the range of allowable plasticity indices specified in the final cover design). Information also needs to be provided to demonstrate that the expected range of tailings and debris disposal configurations would not result in excessive amounts of differential
settlement/distortion in the compacted clay radon barrier that could lead to cracking of that layer
or slope reversal(s) in the final cover system surface. This information, together with engineering
analyses ( calculations, numerical model simulations, etc.) of predicted long-term differential settlement/subsidence within the closed embankment, and consideration of other specified design criteria (e.g., ponding of water not allowed to occur on the final cover surface as a result of long-
term differential settlement or subsidence) must demonstrate the long-term stability of the closed
embankment.
From the information provided in Section 3.2.2.2 and Attachment G of the Reclamation Plan Rev. 4.0 regarding the PMP Event it is unclear whether the method used to calculate the PMP Event is consistent with guidance issued by the NRC after the information presented in
Attachment G was developed (e.g., NRC 2002). Attachment G contains an excerpt from a 1998
document which references a 1990 Hydrologic Design Report as the source of the determined 6-
hour storm rainfall event. A more recent PMP Event Computation (DUSA 2009b) supercedes the 1990 PMP calculation and should be referenced. Information needs to be provided that demonstrates that the proposed riprap sizing for all topslope and sideslope areas is adequate for
the updated PMP Event.
The potential for long-term erosion (sheet and gully) should be adequately mitigated through the
use of riprap and rock mulch in transition and/or channel areas surrounding the reclaimed disposal cells and across the surface of the final reclamation cover system(s). Rock toe aprons may need to be placed at the base of sloped embankments to:
• Stabilize and/or anchor any rock placed on the sideslope
• Provide toe drainage channel, to provide for energy dissipation
• Provide erosion protection at the toe of the embankment
• Allow transitioning of flow from the sideslope to the adjacent ground surface
• Provide protection long-term gully intrusion protection.
Published guidance documents (e.g., NRC 2002; Robinson, et. al. 1998; Apt, et. al. 2008)
provide updated methodologies for determining the median stone size required to resist stone
movement at the transition of the toe of a slope and provide updated empirical data and recommendations regarding the minimum depth and minimum horizontal reach of toe rock aprons at the toes of a stabilized riprap slope. For example, based on rock chute tests, as
referenced in NRC (2002), Robinson et al. (1998) provided a recommendation that the horizontal
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reach (horizontal width) for rock toe aprons be a minimum of 15 times the D50 of the rock in a
rock apron.
Guidance contained in Section 7.2 of Appendix D of NUREG-1623 (NRC 2002, issued after the
NRC’s review of the Revision 3.0 of the Reclamation Plan), indicates that rock with aggregated
rock quality score of less than 65% should be rejected for use in (critical) areas that are frequently saturated areas since such rock is generally more vulnerable to weathering than
occasionally saturated areas where freeze/thaw and wet/dry cycles occur less frequently,.
According to information presented in Attachment H to the Reclamation Plan (Revision 4.0),
rock tested from the Brown Canyon Site borrow site have rock quality scores less than 65% and so would be rejected from use in the rock toe apron areas at the base of the toes of cell outslopes in the final closure design (Section 3.3.5 of Reclamation Plan, Revision 4.0; and Section 6.0 and
Figure A-5.1-4 of Attachment A to that Reclamation Plan). The Reclamation Plan and Plans and
Specifications for Reclamation do not present this information/finding, and are therefore lacking.
Implementing the final closure design, if found acceptable, depends on availability of adequate quantities of suitable materials. Should insufficient quantities of suitably acceptable rock for use in frequently saturated areas be reasonably and practically available, the viability of the final
closure design for these components of the final closure design would be called into question.
Demonstration must be provided that adequate rock quality and quantities are reasonably and
practically available.
NUREG-1623 (e.g., see Appendix D, “Designing Riprap Erosion Protection,” paragraph 2.1.1, Filter Requirements), recommends that a filter or bedding layer comprised of well-graded rock
material be placed on the cover or in locations where rock riprap is to be placed for erosion
protection. Locations where filter s are recommended include impoundment side slopes, toes of
slopes, transition areas, diversion ditches and channels, stilling areas, and flow impact areas. As described in NUREG-1623, such a filter should be designed to bed the riprap and prevent stone penetration into the cover, prevent soil erosion from flow at the stone/soil interface, and prevent
the pooling of precipitation and/or tributary runoff from infiltrating into the cover and waste
materials. 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 are described in NUREG/CR-4620 (Nelson, et al. 1986). Currently, no filter blankets or bedding layers are shown or specified in the Reclamation Plan (Rev. 4.0) in any of
the areas described in NUREG-1623 where filters are generally recommended as discussed
above. 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 the other areas mentioned.
The dimensions shown for the Cell 1 discharge on Figure A-2.2.4-1 in Attachment A of the Reclamation Plan (Rev. 4.0) are not consistent with the channel dimensions of the proposed
channel as indicated in the channel and toe apron design calculations presented in Attachment G
of the Reclamation Plan (Rev. 4.0). These inconsistencies must be resolved.
The Sedimentation Basin Detail figure provided as Figure A-2.2.4-1 in Attachment A of the Reclamation Plan (Rev. 4.0) lacks clearly labeled contours and grading along the length and sides of the proposed Cell 1 drainage ditch. NRC Regulatory Guide (RG) 3.8 (NRC 1992),
Section 2.1 requires that license applicants describe any plans for site modifications, and provide
a contour map of the site with elevation contours of an interval suitable to show significant
variations of the site environs and drainage gradients. Section 3.1 of RG 3.8 specifies that a map
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of the site area should be included that clearly depicts contours and shows a scale that will permit
the measurement of distances with reasonable accuracy. This required information need to be
provided.
NUREG-1620 (NRC 2003), Section 3.1.3, also specifies that the hydrologic description of the
site will (only) be considered acceptable if:
“(1) The description of structures, facilities, and erosion protection designs is sufficiently
complete to allow independent evaluation of the impact of flooding and intense rainfall.
(2) Site topographic maps are of good quality and of sufficient scale to allow independent
analysis of pre- and post-construction drainage patterns.
(3) The reclamation plan contains sufficient information for the staff to independently evaluate the hydraulic designs presented. In general, detailed information is needed for
each method that is used to determine the hydraulic designs and erosion protection
provided to meet NRC regulations. NUREG–1623 (NRC, 2002) discusses acceptable
methods for designing erosion protection to provide reasonable assurance of effective long-term control and, thus, conform to NRC requirements. NUREG–1623 (NRC, 2002) also provides discussions and technical bases for use of specific criteria to meet the
1,000-year longevity requirement, without the use of active maintenance. Specific design
methods are provided and form the primary basis for staff review of erosion protection
designs.”
A geologic map with accompanying cross section(s) is (are) needed to define the earth materials that will be penetrated by the drainage ditch and that would line the sides and bottom of the ditch
along its entire reach. This information is needed to support the design of the channel to ensure
the adequacy of the design for providing long-term erosion protection. Additional information
needs to be provided to demonstrate the adequacy of the sedimentation basin and Cell 1 discharge channel system with respect to long-term scour and erosion protection, and to justify that the design is based on or considers potentially applicable design guidelines. This necessary
information needs to be provided.
The suitability of the proposed allowable peak channel velocity of 8–10 fps, based on the
assumption of bedrock material, has not been demonstrated. Published guidance documents (e.g., see Nelson, et al. 1986) recommend a maximum allowable velocity for bedrock material of 6-8 fps. The allowable peak velocities would be lower for substrates consisting of non- bedrock
materials. This inconsistency needs to be resolved.
Geologic conditions that could justify factoring in various adjustments into the determination of
an appropriate Manning ‘n’ value or range of Manning ‘n’ values s for (various segments of) the channel are likely to vary along the reach of the proposed Cell 1 drainage channel. Incorporating correction factors to the 0.025 suggested Manning ‘n’ coefficient that account for roughness of
the bedrock material should be considered. The selected (base) value of 0.025 assumes a smooth
bedrock-lined channel along the entire channel length. It is likely that the channel would exhibit
some irregularity and variability along its length. For example, the channel could have variable degrees of roughness due to initial blasting vs. ripping of rock during channel construction; differences in subgrade geologic conditions (e.g. lithology); and possible variable amounts of
accumulation of debris, vegetation, and roots within the channel over the long term as a result of
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natural processes; differential erosion effects; and other factors or processes. Appropriate
adjustments (e.g., see Acrement and Schneider 1989) should be included to account for such
factors in the determination of appropriate Manning coefficient(s) for the discharge channel
along the channel’s reach.
The slope stability analysis provided in the Revision 4 Reclamation Plan is applicable to a final cover system that the DRC understands may yet be modified. If at some future date, the cover
system is modified, the final slope stability analyses would need to be re-evaluated to ensure it is
directly applicable.
As a part of a proposed engineering design for tailings Cell 4B, DUSA provided a Technical Memorandum (Tetra Tech 2010) that contains an updated seismic hazard evaluation study that includes:
• Summary of seismic studies done through 2006 to develop a design peak ground
acceleration (PGA) for the design of disposal cells and for use during the operational
period of those cells
• Review of updated data (through January 2010) on seismic activity within 200 miles of
the White Mesa Mill Site
• Derivation of an updated predicted peak horizontal ground acceleration (peak HGA)
value, based on a 10,000-year return period, for use in the final disposal closure design effort for proposed Cell 4B.
The study addressed updated published information, including the most recent USGS National
Seismic Hazard Maps, and also considered other studies, including 2008 deaggregation data,
Next Generation Attenuation Project information from 2007, and consideration of an updated
attenuation relationship published in 2007. Updated evaluation should, therefore, be described, applied to, and referenced in the final slope stability analyses in Reclamation Plan, Rev. 4.0.
REFERENCES:
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.
Abt, S.R., Johnson, T.L., Thornton, C.I., and Trabant, S.C. 1998. “Riprap Sizing at Toe of
Embankment Slopes,” Journal of Hydraulic Engineering, Vol. 124, No. 7, July 1998,
pp. 672–677.
Acrement, G.J, and Schneider, V.R. 1989. Guide for Selecting Manning’s Roughness Coefficients for Natural Channels and Flood Plains. United States Geological Survey Water-supply Paper 2339. URL: http://www.fhwa.dot.gov/bridge/wsp2339.pdf.
Daniel, D.E. (Editor) 1993. Geotechnical Practice for Waste Disposal. Chapman & Hall
Publishers, 2-6 Boundary Row, London, UK, 677 pp.
Denison Mines (USA) Corporation. 2009a. Reclamation Plan, Revision 4.0, White Mesa Mill, Blanding, Utah, Exhibit C: November 2009
Denison Mines (USA) Corp. 2009b. “ Re: Cell 4B Lining System Design Report, Response to
DRC Request for Additional Information – Round 3 Interrogatory, Cell 4B Design”,
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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 Remediation Action Project, Slick Rock , Colorado.
Subcontract Documents: Bid Schedule, Special Conditions, Specifications, Subcontract
Drawings. February 1995.
DOE. 2009a. 2008 UMTRCA Title I Annual Report: Slick Rock, Colorado. January 2009.
DOE. 2009b. 2008 UMTRCA Title I Annual Report: Rifle, Colorado. January 2009.
DOE. 2009c. 2008 UMTRCA Title I Annual Report: Grand Junction, Colorado. January 2009.
DOE. 2009d. 2008 Annual Inspection Report for the Weldon Spring, Missouri Site. January
2009.
DOE. 2000. WSSRAP Disposal Facility Technical Specifications, Section 2300: Waste Removal, Handling, and Placement. WP-437, Disposal Cell Construction. May 15, 2000.
DOT (U.S. Department of Transportation).Federal Highway Administration. 2006. Hydraulic
Design of Energy Dissipators for Culverts and Channels. Hydraulic Engineering Circular
No. 14, Third Edition, Publication No. FHWA-NH1-06-086, 286 pp. URL:
http://www.fhwa.dot.gov/engineering/hydraulics/pubs/06086/.
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.cgi%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.
Itasca 2009. FLAC3D® – Advanced Three Dimensional Continuum Modeling for Geotechnical
Analysis of Rock, Soil, and Structural Support. Itasca. URL: http://www.itascacg.com/flac3d/index.php.
Koerner, R.M. and Daniel, D.E., 1994, “Technical Equivalency Assessment of GCLs to CCLs”,
Geosynthetic Liner Systems: Innovations, Concerns and Designs, Koerner, R.M. and
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Wilson-Fahmy, R.F. Editors, IFAI, 1994, proceedings of a conference held in
Philadelphia, Pennsylvania, USA, pp. 265-285.
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 (U.S. Nuclear Regulatory Commission). 1992. Preparation of Environmental Reports for
Uranium Mills, Regulatory Guide 3.8, October, 1992.
NRC 2002. U.S. Nuclear Regulatory Commission, “Design of Erosion Protection for Long-Term Stability”, NUREG-1623, September 2002.
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.
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, pp. 166-171.
Robinson, K.M. Rice, C.E., and Kadavy, K.C. 1998. Design of Rock Chutes. Transactions of
ASAE, Vol. 41, No. 3, pp. 621-626. URL:
http://www.ksda.gov/includes/document_center/structures/Structures/HL178.pdf.
Tetra Tech 2010. Technical Memorandum – White Mesa Uranium Facility, Seismic Study Update for a Proposal Cell, Blanding, Utah, February 3, 2010, Attachment E to Denison
Mines (USA) Corp., White Mesa Uranium Mill - Second Round of Interrogatories from
Review of License Amendment Request and Environmental Report for Cell 4B, February
8, 2010.
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INTERROGATORY WHITE MESA RECPLAN 04/01: 10CFR40, APPENDIX A, CRITERION 6(1): COVER AND CLOSURE AT END OF MILLING OPERATIONS
REGULATORY BASIS:
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:
1. Radon Flux (Refer to Sections 3.3.1 and 3.3.2 and Attachment F, including Table 1, to the Reclamation Plan, Rev. 4.0) [Note: This interrogatory item was previously provided to DUSA in January 2010 as part of the Round 2 Interrogatories submitted on the Cell 4B Environmental Report]:
a. Please provide information describing the specific soil moisture data that are
proposed to be used in the future radon emissions calculations, where the proposed
clay borrow material soil samples tested are located in relation to the White Mesa Mill Site, and information on the sampling depths of the clay borrow soil samples.
b. Please provide information regarding the laboratory test method that was used for
determining the long-term moisture content of the clay soil samples tested.
c. Please provide information regarding adjustments, if any, that were made to account
(adjust) for differences in site conditions at the borrow site(s) compared to the Mill Site, with information to support such adjustments.
d. Please provide information justifying that the long-term moisture content selected
to represent the radon barrier layer in the radon emission calculations is
conservative (e.g., relative to guidance provided in NRC Regulatory Guide 3.64
[NRC 1989] and Technical Approach Document, Rev 2, 1989, UMTRA-DOE/AL 050425.0002, DOE 1989, Section 7).
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BASIS FOR INTERROGATORY:
Attachment F of the Reclamation Plan, Table 1 (“Selected Model Input Data”), lists water
content percentages for the radon barrier layer from locations listed as Clay (Site #1), Clay (Site
#2), and Clay (UT-1). However, no information has been provided as to where these three
samples were collected at the borrow area(s), or the depths from which they were collected. Also, in Attachment F of the Reclamation Plan, Table 1, the footnote given for the 14.1% moisture content value listed states that this percentage was selected based on an “average of two
tests”. No laboratory analysis results/data or information on types of soil test methodologies used
was included. Likewise, no information was provided regarding any adjustments that were made,
if any, to the laboratory soil testing results to account for differences in soil conditions between the borrow site(s) and the engineered condition(s) that will exist at Mill Site after cover construction.
NRC Regulatory Guide 3.64 (NRC 1989) specifies that information on the location of the clay
borrow site(s) proposed for supplying clay soils for the clay radon barrier layer in final disposal
cell covers needs to be provided with adjustments made, as appropriate, to account for any differences in conditions between the borrow site(s) and the disposal site as necessary. Also, it is recommended that samples of the clay soil materials be obtained from depths between 120 and
500 cm. In the information provided by DUSA (e.g., Table 1 in Attachment F of the Reclamation
Plan, Revision 4.0), the submittal suggests that the long-term soil moisture content value selected
for use in a previous radon barrier emission calculation was estimated from an “average of two tests.” That approach does not appear to be conservative with respect to guidance contained in Section 7.1.1 of DOE 1989, which states that “all design parameters, except moisture content,
are average values; (however) moisture content is conservatively estimated.” DOE 1989, Section
7.1.3, describes ASTM laboratory soil test methods considered acceptable for determining long-
term moisture contents. As an acceptable alternative, a conservative long-term moisture content for the radon barrier layer for radon emissions calculations can be determined using a relationship such as the one described in NRC Regulatory Guide 3.64 developed by Rawls and
Brakensiek (1982).
REFERENCES:
DOE (U.S. Department of Energy). 1989. Technical Approach Document, Revision II. UMTRA-DOE/AL 050425.0002.
NRC (U.S. Nuclear Regulatory Commission). 1989. Regulatory Guide 3.64 (Task WM 503-4) -
Calculation of Radon Flux Attenuation by Earthen Uranium Mill Tailings Covers. June
1989.
NRC. 2008. Standard Format and Content of License Applications for Conventional Uranium Mills, Draft Regulatory Guide DG-3024, May, 2008.
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.
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, pp. 166-171.
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INTERROGATORY WHITE MESA RECPLAN 05/01: 10 CFR PART 40, APPENDIX A; UAC R317-3-1; AND UAC R317-3: CONSTRUCTION QUALITY CONTROL AND ASSURANCE
PRELIMINARY FINDING:
Refer to R313-25-7. Specific Technical Information. The application shall include certain technical information. The following information is needed to determine whether or not the
applicant can meet the performance objectives and the applicable technical requirements of R313-
25:
…(10) Descriptions of quality assurance programs, tailored to low-level waste disposal, including audit and managerial controls, for the determination of natural disposal site characteristics and for quality control during the design, construction, operation, and closure of the land disposal facility
and the receipt, handling, and emplacement of waste.
Refer to R317-3-1(1.7). 1.7. Construction Supervision. The applicant must demonstrate that
adequate and competent inspection will be provided during construction. It is the responsibility of the applicant to provide frequent and comprehensive inspection of the project.
Refer to R317-3-10(4)(E). E. Construction Quality Control and Assurance. A construction
quality control and assurance plan showing frequency and type of testing for materials used in
construction shall be submitted with the design for review and approval. Results of such testing,
gradation, compaction, field permeability, etc., shall be submitted to the Executive Secretary.
INTERROGATORY STATEMENT:
Please revise and expand the Quality Plan for Construction Activities, White Mesa Project,
Blanding, Utah (Attachment B to the Reclamation Plan, Revision 4.0) and submit it as a
Construction Quality Assurance/Quality Control Plan (CQA/QC Plan) for site reclamation.
Provide an expanded CQAQC Plan that at a minimum, provides the following:
1. Include an organization chart that has sufficient detail to show the lines of communication and authority (reporting relationships and directions) between the
different CQA/QC personnel and entities.
2. Include sufficient detail to indicate who is responsible (between the Site Manager,
Quality Control Officer, Quality Assurance officer, the DRC Project Manager, Quality Control Technicians, and any others) for, and when acceptance of the construction work identified will occur.
3. Clarify responsibilities and criteria for acceptance of work and procedures, required
actions, and timelines to remediate material specification or construction errors when
identifying and responding to non-conformances, so that CQA/QC Plan clearly identifies responsibility assignments or procedures for when there is non-conformance, and how these will be addressed and corrected, and ensures the timely implementation and
documentation of the completed corrective measure(s).
4. Describe minimum required experience and qualifications for all personnel indentified in
the Organizational Structure section of the CQA/QC Plan.
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5. Include information on the Quality Assurance Testing Laboratory, including minimum
experience and qualifications, and information indicating that the required test
procedures and testing frequencies prescribed in the final CQA/QC Plan (for samples
obtained from the site during reclamation activities) will be implemented by the testing
laboratory. Please demonstrate that this soils testing laboratory will be currently certified and accredited by the AASHTO Material Reference Laboratory (AMRL) for all soil /
engineering related tests conducted on earth materials at the site.
6. List and describe all CQA/QC activities related to earthwork operations that will occur
during reclamation activities, including:
a. A listing of earthwork activities.
b. Procedures for observing and performing conformance testing of proposed
materials of construction, and for inspection and protection of soil stockpiles.
c. Information regarding the review and evaluation of testing performed by
Contractor(s) and review and approval of Contractor’s proposed construction methods and proposed equipment.
d. A statement regarding procedures and (estimated maximum) timeframes required
for de-watering and stabilizing the tailings, including verification settlement
monitoring, and obtaining approval from the DRC for the final waste fill grades and
elevations before placement of cover materials.
e. A description of the construction, implementation, and sample collection and testing procedures for an initial test pad or pads or any additional test pad
constructed, if needed as part of the reclamation activities. Discuss the size and
slope (inclination) of each such test pad; equipment to be used and number of
equipment passes to be used; and how the test pad(s) will be used to demonstrate and verify that the specified minimum requirements for the final cover system and other disposal system components, as appropriate, can reliably be achieved during
the construction work. Include information on the criteria to be used for
determining when a test pad is needed. Provide information on the types and
locations of tests to be conducted on the test pad. Provide test methods for testing density (e.g., ASTM D-698 and/or ASTM D-1557), Atterberg Limits, particle size analysis, moisture/density (nuclear method and sand cone) and moisture content,
relatively undisturbed saturated hydraulic conductivity, and in-situ large-scale
saturated hydraulic compacted clay layer in the test pad (e.g., Sealed Double-Ring
Infiltrometer method [ASTM 5093-02 (ASTM 2008)], or other DRC-approved large-scale in-situ sampling/testing method), in accordance with applicable published guidance documents (e.g., Daniel and Koerner 1993; Daniel and Koerner
2007; ASTM 2008). Include a description of temperature or other weather
conditions and constraints that would be associated with test pad construction and
procedures for reworking any areas where a failing test result (e.g., permeability in excess of the specified minimum value) is obtained. Specify all ASTM methods as applicable and testing frequencies (recommend use of a tabular format).
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f. A description of measurements, inspections, observations to be made during
construction of each of the cover system layers, including monitoring of moisture
conditioning, mixing and/or blending/processing for uniformity of material and
content, field density tests, and other parameters as appropriate. Specify (in the
revised version of the Quality Plan in Attachment B) all ASTM methods as applicable and testing frequencies (recommend use of a tabular format). Indicate
all applicable and relevant guidance and standards that will be addressed by the
testing and inspection program, including NUREG/CR-3356 (NRC 1983); NRC
Regulatory Guide 3.11, Rev. 3 (NRC 2008); ASTM Standards, and other guidance considered applicable and relevant (e.g., Daniel and Koerner 1993; Daniel and Koerner 2007). Include descriptions of procedures for observing, testing, and
documenting placement and compaction activities of each layer of the final cover
system, including lift thickness placement, compaction equipment usage, and
number of passes made with equipment. Include information on observations and sampling procedures related to construction and testing of:
• The “platform fill and grading layer;”
• The upper portion (sublayer) of the “platform fill and grading layer”, including
specified restrictions on, or prohibition of, debris waste placement within that
sublayer, and the thickness of that sublayer for which such restrictions or prohibition will apply);
• The radon barrier layer;
• The “compacted random fill layer” (frost barrier and water storage layer; and/or
• Any other layers proposed for inclusion in the selected final cover system.
g. A description of temperature (or other weather conditions/constraints) and minimum moisture content (desiccation prevention) that would be associated with the radon barrier layer construction.
h. A description of procedures to be followed to rework materials in portions of layers
for which a failing test result occurs and procedures for notification of the Site
Manager and the DRC Manager for any failed test or failed retest result or for directing and approving further reworking of the failing material. Please include a description of maximum timeframes for such verification testing, required
approvals and notification and approval time frames. Specify all ASTM methods as
applicable and related testing frequencies.
i. A description of procedures for conducting and documenting post-construction inspections and for completing corrective actions and materials testing, as required, in conjunction with construction of the compacted layer prior to its final
acceptance.. Such activities should include inspecting for any cracks/desiccation in
the compacted clay layer; inspecting any areas that are damaged or improperly
mixed or compacted; and inspecting:
• Clod sizes (prior to compaction)
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• Presence of areas that have been excessively eroded by rainfall or as a result of
construction activities
• Areas containing excessive organic material or other deleterious and/or unsuitable (e.g., uncompactable) materials
• Depressions
• Other irregularities in the cover layers
• Procedures for completing and recording any repairs performed.
j. A description of methods for repairing/backfilling and re-testing repairs made to
address any holes or unrepaired damage in the constructed compacted clay layer
(radon barrier layer) from density tests, field permeability tests, or other tests.
k. Revised versions of Form No. F-23 (Compliance Report) and Form No. F-26 (Design Change Order) to reflect approval of DRC Project Manager rather than that
of the NRC Project Manager.
l. A revised version of Form No. F-26 (Design Change Order) as needed to reflect the
current discrepancy between this form, which requires approval by the Design
Engineer, and the absence of a description of this position/person in Section 2 (Organizational Structure) of the Quality Plan for Construction Activities
(Attachment B).
m. A description of contents of a Final Certification/CQA Documentation Report that
will be prepared and submitted by the State of Utah registered Professional
Engineer that indicates that the project was constructed in accordance with the construction drawings, specifications, and the CQA/QC Plan. The report should
include, at a minimum, a summary of all CQAQC operations, construction
equipment and processes, results, and observations of conformance / verification
testing, and any actions taken to resolve construction problems encountered, as-
built drawing(s) and details, field notes, and photographs. The report must be prepared under the supervision of and stamped with the seal of a Utah registered
Professional Engineer.
n. Include information indicating that the Quality Control Officer (CQO) for
implementing and managing the CQA/QC Plan during reclamation activities, as
identified in Quality Plan for Construction Activities (Attachment B), will be an independent Utah registered Professional Engineer, party who will conduct both
direct field observations and document reviews.
BASIS FOR INTERROGATORY:
Section 7 of Attachment A (Quality Control/Quality Assurance) of the Reclamation Plan,
Revision 4, and the Quality Plan for Construction Activities (Attachment B to that Reclamation Plan) do not adequately specify CQA/QC activities that will need to be completed and
documented during the reclamation work at the White Mesa Mill Site in order to permit a
transparent, documented, and verifiable certification that the project will have been constructed
in accordance with the construction drawings, specifications, and the CQA/QC Plan. Further, the
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information presented in Section 7 of Attachment A of the Reclamation Plan (Rev. 4.0) and in
the Quality Plan for Construction Activities (Attachment B to the Reclamation Plan) does not
address guidelines or incorporate several ASTM test methods (e.g., ASTM D-698, ASTM D-
1556, ASTM D-2487, ASTM D-2922, ASTM D-3017, ASTM D-2937, ASTM D-4318, ASTM
D-4643, ASTM D-5084) that have been either adopted or updated since the time the NRC last reviewed the White Mesa Mill Reclamation Plan (early 2000s).
Sections 2.6.2 and 2.6.3 of NUREG-1620 (NRC 2003) indicate that a review be performed of
proposed construction quality control programs for verifying that adequate provisions are in
place for ensuring that construction will be in accordance with the approved reclamation plan, and that such a review include, in particular, details of the proposed testing and inspection program, including the type and frequency of tests proposed, for comparison with NRC-specified
guidance on testing and inspection , including NUREG/CR-3356 (NRC 1983).

Section 3.4 of NUREG-1620 (NRC 2003) identifies “construction considerations, including specifications, quality assurance programs, quality control programs (“…to ensure that adequate measures are being taken to construct the design features according to accepted engineering
practices”), and inspection programs, as a key area for review when conducting reviews of
erosion protection designs for reclamation plans.
With regard to compliance with requirements of 10 CFR Part 40, Appendix A, Criterion 5(A) that relates to the design of liners for surface impoundments, Section 4.4.3 of NUREG-1620 indicates that “the design of a clay or synthetic liner and its component parts should be
presented. At a minimum, design details, drawings, and pertinent analyses should be provided
and that expected construction methods, testing criteria, and quality assurance programs should
be presented. Planned modes of operation, inspection, and maintenance should be discussed in the application.” Although these guidelines apply to clay liners, the same guidelines would be applicable to the compacted clay radon barrier layer in the final cover system.
With respect to demonstrating compliance with radon attenuation criteria specified in 10 CFR
Part 40, Appendix A, Criterion 6(1) and Criterion 6(5), Section 5.3.1 of NUREG-1620 (NRC
2003) indicates that “the materials testing programs [should] employ appropriate analytical methods and sufficient and [ensure that] representative samples were tested to adequately determine material property values for both cover soils and contaminated materials. In the
absence of sufficient test data, [ensure that] conservative estimates are chosen and justified…and
[ensure that] the quality assurance program for parameter data is adequate and the data are
available for inspection.”
NRC’s Regulatory Guide 3.11, Rev. 3 (NRC 2008) also provides some guidance relevant to typical testing procedures and testing frequencies for some parameters during embankment
construction.
Maximum estimated timeframes for completing dewatering of the tailings, a critical-path item
for the reclamation schedule, should be described in the Reclamation Plan so that a conservative estimate of the costs for carrying out final reclamation, including conducting the CQA activities described in this interrogatory, can be estimated for inclusion in the financial surety.

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REFERENCES:
American Society for Testing and Materials (ASTM). 2008. Standard Test Method for Field
Measurement of Infiltration Rate Using a Double-Ring Infiltrometer with a Sealed Inner
Ring, Test Designation ASTM D5093 - 02(2008), American Society for Testing and
Materials, West Conshohoken, PA, 2008.
Daniel, D. E., and Koerner, R.M. 1993. Technical Guidance Document: Quality Assurance and
Quality Control for Waste Containment Facilities. EPA/600/R-93/182. Office of
Research and Development, Washington, D.C. 305 pp.
Daniel, D. E., and Koerner, R.M. 2007. Waste Containment Facilities – Guidance for Construction Quality Assurance and Construction Quality Control of Liner and Cover Systems. 2nd Edition. ASCE Press, Reston, VA. 353 pp.
NRC (U.S. Nuclear Regulatory Commission) 1983. NUREG/CR-3356. Geotechnical Quality
Control: Low Level Radioactive Waste and Uranium Mill Tailings Disposal Facilities.
Prepared for U.S Nuclear Regulatory Commission, 108 pp. plus Appendices, July 1983.
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. Regulatory Guide 3.11, Rev. 3. Design, Construction, and Inspection of
Embankment Retention Systems at Uranium Recovery Facilities. November 2008.
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INTERROGATORY WHITE MESA RECPLAN 06/01: 10CFR40, APPENDIX A, CRITERION 9: 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 an 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.
This will yield a surety that is at least sufficient at all times to cover the costs of decommissioning and reclamation of the areas that are expected to be disturbed before the next license renewal. The term of the surety mechanism must be open ended, unless it can be
demonstrated that another arrangement would provide an equivalent level of assurance. This
assurance would be provided with a surety instrument which is written for a specified period of
time (e.g., 5 years) yet which must be automatically renewed unless the surety notifies the beneficiary (the Executive Secretary) and the principal (the licensee) some reasonable time (e.g., 90 days) prior to the renewal date of their intention not to renew. In such a situation the surety
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requirement still exists and the licensee would be required to submit an acceptable replacement
surety within a brief period of time to allow at least 60 days for the regulatory agency to collect.
Proof of forfeiture must not be necessary to collect the surety so that in the event that the licensee could not provide an acceptable replacement surety within the required time, the surety shall be automatically collected prior to its expiration. The conditions described above would
have to be clearly stated on any surety instrument which is not open-ended, and must be agreed
to by all parties. Financial surety arrangements generally acceptable to the Executive Secretary
are:
(a) Surety bonds;
(b) Cash deposits;
(c) Certificates of deposits;
(d) Deposits of government securities;
(e) Irrevocable letters or lines of credit; and
(f) Combinations of the above or such other types of arrangements as may be approved by the Executive Secretary. However, self insurance, or any arrangement which essentially constitutes
self insurance (e.g., a contract with a State or Federal agency), will not satisfy the surety
requirement since this provides no additional assurance other than that which already exists
through license requirements.”
INTERROGATORY STATEMENT:
1. Preliminary Decommissioning Plan
Please provide a preliminary Decommissioning Plan as an attachment to the Reclamation Plan (refer to NUREG-1620, Rev. 1, Section 5.2) that describes expected decommissioning activities
in sufficient detail to support cost estimates for surety purposes. Please include the following
elements and address them in appropriate detail, as follows:
a. Plans and procedures for disconnecting, isolating, draining, removing and disposing of all
utilities including, but not limited to lines and appurtenances for telephone, electrical
power, natural and tanked gas, water supply, sewer (or septic tank drainfields), and fuels. Include structures, tanks, piping and equipment used in conjunction with the uranium milling operations, including the plan for managing all hazardous and radioactive
materials.
b. Consider approaches for identifying radiological hazards before initiating dismantlement
of structures and equipment and for detection and cleanup of removable contamination
from such structures and equipment in order to minimize occupational radiation
exposure.
c. Describe appropriate survey methods for determining the extent of equipment
contamination before initiating decontamination work. Focus, in particular, on those parts of the mill process system that are likely to have accumulated contamination over long time periods (e.g., pipes, ventilation, equipment, effluent control systems, and facilities
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and equipment used in or near the yellowcake dryer area). Describe any plans for the
decontamination of equipment for release for unrestricted use.
d. Measures for cleanup of windblown tailings and other soils contaminated from mill
operations and for sampling and surveys to document that soils have been cleaned to
acceptable levels. Address the means for disposing of any ore remaining on site following
the cessation of mill operations. Provide procedures to identify, excavate, transfer, and deposit within designated tailings cells all soils on and adjacent to the processing site that exceed the standards in 10 CFR Part 40, Appendix A, Criterion 6(6), due to site activities.
Describe how the plan will be substantiated by the radiological characterization data and
site operating history. (Refer also to Item 1 of Section 5.2.2 of NUREG-1620, Rev. 1 for
additional guidance.)
e. Proposed soil background values (different geological areas may need separate
background values) for Ra-226, and for U-nat, Th-230, and/or Th-232, as appropriate. Said background values must be justified with supporting soil sampling / analytical data. (Refer also to Item 2 of Section 5.2.2 of NUREG-1620, Rev. 1 for additional guidance.)
f. If elevated levels of uranium or thorium are expected to remain in the soil after the Ra-226 criteria have been met, a commitment to use the “radium benchmark dose approach
described in Appendix H of NUREG-1620, Rev. 1 in developing decommissioning
criteria for the radionuclides that remain at elevated levels. (Refer also to Item 3 of
Section 5.2.2 of NUREG-1620, Rev. 1 for additional guidance.)
g. Modify the plan to ensure that the instrumentation and procedures used for soil
background analyses and the radium-gamma correlation are the same or very similar to those proposed to provide verification data to ensure consistency of measurement data. Please also demonstrate how the proposed instrumentation has the appropriate sensitivity,
and that proposed soil sampling / analytical procedures are adequate to provide reliable
soil activity data. (Refer also to Items 4 and 5 of Section 5.2.2 of NUREG-1620, Rev. 1
for additional guidance.)
h. A detailed quality assurance and quality control plan for all aspects of decommissioning.
Provide and justify the basis for accepting or rejecting data and a procedure for sampling additional grids when a verification Ra-226 sample fails to meet the standard. (Refer also to Item 6 of Section 5.2.2 of NUREG-1620, Rev. 1 for additional guidance.)
i. Final verification (status survey) procedures that demonstrate compliance with the site soil and structure cleanup standards. Specify survey instruments and provide procedures
for their proper calibration and testing. The proposed verification soil sampling density
must consider and justify (1) detection limits of sample analyses, (2) the extent of
expected contamination (unaffected area could have fewer measurements than affected areas), and (3) limits to the gamma survey for the potentially contaminated area to be sampled. Justify the gamma guideline value to be used for verification. Commit to
provide the verification soil radium-gamma correlation and the number of verification
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grids that had additional removal because of excessive Ra-226 values, to confirm that the
gamma guideline value was adequate. Commit to providing adequate data collection
beyond the excavation boundary (buffer zone). For structures expected to remain onsite,
provide plans and procedures that will demonstrate compliance with the limits for the
surface activity dose in Appendix H of NUREG-1620, Rev. 1. (Refer also to Item 7 of Section 5.2.2 of NUREG-1620, Rev. 1 for additional guidance.)
j. The location where will be maintained records important to decommissioning procedures, documenting the protection of health and safety, and demonstrating that
decommissioning was completed as soon as practicable, as required by 10 CFR 40.42 and
Appendix A, Criterion 6A. (Refer also to Item 8 of Section 5.2.2 of NUREG-1620, Rev.
1 for additional guidance.)
k. A description of methods to be used to control non-radiological hazards associated with
the wastes as required by 10 CFR Part 40, Appendix A, Criterion 6(7). (Refer also to Item 9 of Section 5.2.2 of NUREG-1620, Rev. 1 for additional guidance on cost elements appropriate for establishing surety amounts for conventional uranium mills.)
l. Procedures, equipment, and maximum timeframes needed for tailings de-watering and stabilization, including settlement monitoring stands, elevation surveys, generation of
reports, and related performance criteria.
m. Qualifications, skills and abilities of all personnel involved in the reclamation and
decommissioning process, including but not limited to: site sampling / inspections,
consulting, and closure report preparation.
n. Minimum number, types, and locations of samples to be collected and analyzed to verify
closure construction, decommissioning, and decontamination of the site.
o. Minimum number, types and locations of Radon-222 measurements to be made after
embankment closure to confirm and verify compliance with NESHAPS requirements (see
Interrogatory WhiteMesa RecPlan 07/01, below).
2. Cost Estimates for Reclamation and Decommissioning (Refer to Section 3, Attachment
A, and Attachment C of the Reclamation Plan):
It is prudent to provide a reclamation and decommissioning cost estimate with the revised
Reclamation Plan, that itemizes each cost component in sufficient detail and that defines the
basis for each cost component. The licensee should demonstrate that the total cost is reasonably
conservative for the area of the site and the expected reclamation and decommissioning activities. (Refer also to Item 10 of Section 5.2.2 and Appendix C of NUREG-1620, Rev. 1 for additional guidance.)
a. Provide estimated costs for completing final closure of the Mill Facility, including the
costs for constructing those revised final closure cover and drainage systems and
appurtenances for determining/verifying the financial surety requirements for the White
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Mesa Mill with all tailings management cells, including Cells 4A and 4B, and any new
structures, features, or other appurtenances associated therewith.
b. Provide updated information and details pertaining to anticipated required reclamation
activities for any tailings or waste disposal areas or other contaminated areas, including
contaminated groundwater plumes known to have originated from the mill and its facilities and operations, viz., the chloroform plume. Provide cost estimates for each
required reclamation activity. Probabilistic cost estimates can be used to represent the
costs of completing required remedial activities where uncertainty exists, such as
remediation of groundwater plumes. Software packages that would support the
development of probabilistic cost estimates include Crystal Ball®, @Risk®, and GoldSim®, all of which are commercially available and allow cost elements to be defined as
probability distributions and develop cost distributions using Monte Carlo simulations.
c. Provide updated cost estimates for carrying out the preliminary Decommissioning Plan.
d. Please provide a commitment to submit the final decommissioning plan for the Division’s
review 12 months ahead of scheduled closure as required by UAC R313-22-36(4).
BASIS FOR INTERROGATORY:
NRC Regulatory Guide 3.8 (NRC 1982), Chapter 9, indicates that detailed discussions should be
provided for the following:
1. Plans for reclaiming and restoring lands disturbed by mining and milling activities.
These plans should provide sufficient details for the staff to assess the suitability of these
plans when compared to other alternatives (e.g., horizontal-vertical slope, type of cover,
sources and thicknesses of cover materials, revegetation species, schedule of events from shutdown through final reclamation).
2. A technical and financial feasibility assessment on methods and costs of mill
decommissioning and site reclamation, including tailings area.
3. Financial arrangements to be made (such as bonding arrangements) to ensure that
adequate funds will be available for mill decommissioning, site reclamation, and restoration when operations are concluded.”
NRC Draft Guide (DG)-3024 (NRC 2008), Section 8.3, also indicates that Criterion 9 of
Appendix A to 10 CFR Part 40 specifies that each mill operator must establish financial surety
arrangements before the commencement of operations to ensure 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. In the application, a licensee should provide sufficient information to verify that the amount of coverage provided by a financial surety
arrangement will permit the completion of all decontamination, decommissioning, and
reclamation of sites, structures, and equipment used in the recovery and production of uranium
and the concomitant generation of byproduct material. This document also specifies that a
licensee should calculate the cost estimate on the basis of completion of all activities by a third party. The surety must also cover the payment of the charge for long-term surveillance and
control of the site as required by Criterion 10 of Appendix A to 10 CFR Part 40 (See Appendix C
“
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to NUREG-1620 for additional information on the scope and content of the cost information to
be submitted for financial assurance purposes.)
NUREG-1620 (NRC 2003), Section 4.4.3(10), specifies that a licensee must maintain a financial
surety for the cleanup of contaminated ground water, with the surety sufficient to cover the
anticipated cost and time frame for achieving compliance, before the land is transferred to the long-term custodian. This document also indicates that the financial surety must be sufficient to
cover the cost of corrective action measures that will have to be implemented if required to
restore groundwater quality to the established site-specific standards before the site is transferred
to the government for long-term custody. Guidance on establishing financial surety is presented in NRC 1988 and NRC 1997. Appendix C to this standard review plan provides an outline of the cost elements appropriate for establishing surety amounts for conventional uranium mills. The
document indicates that financial surety review should be considered acceptable if the
applicant’s assessment and independent assessment of the surety amounts are reasonably
consistent.
A cost estimate for completing corrective action of existing identified groundwater contamination known to have originated from the mill and its facilities and operations needs to
be provided and be included in the financial surety. Probabilistic cost estimates can be used
when uncertainty exists in the parameters that enter into the cost estimate, including quantities,
unit costs, and lump sum estimates. Based on information about these cost elements, the cost elements can be represented as probability distributions. The probability distribution for the cost elements can then be evaluated randomly hundreds or thousands of times in a Monte Carlo
simulation to develop a distribution of estimated costs. Given the required level of confidence
that actual costs will not exceed financial assurances provided, the cost estimate distribution can
be used to determine the required level of financial assurance. The costs can be estimated using probabilistic techniques and to an extent dictated by the amount of information that is available. As more defining data become available, uncertainty in the cost estimate can be reflected by
revising the probability distributions that represent the cost elements, thereby reducing the
uncertainty of the cost estimate.
Finally, NUREG-1620 (NRC 2003), Section 5.2.3, specifies that, as required by 10 CFR Part 40 Appendix A Criteria 9 and 10, a licensee must maintain a financial surety, within the specific license, for the surface reclamation and decommissioning, with the surety sufficient to recover
the anticipated cost and time frame for achieving compliance, and include the long-term
surveillance as outlined in guidance for establishing financial surety arrangements, as presented
in NRC 1988 and NRC 1997. Appendix C to NUREG-1620 provides an outline of the cost elements appropriate for establishing surety amounts for conventional uranium mills.
REFERENCES:
Denison Mines (USA) Corporation. 2009. Reclamation Plan, Revision 4.0, White Mesa Mill,
Blanding, Utah, November 2009.
NRC (U.S. Nuclear Regulatory Commission). 1988. Technical Position on Financial Assurances for Restoration, Decommissioning, and Long-Term Surveillance and Control of Uranium Recovery Facilities. Washington DC.
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NRC. 1982. Preparation of Environmental reports for Uranium Mills, Regulatory Guide 3.8,
October 1992.
NRC. 1997. Annual Financial Surety Update Requirements for Uranium Recovery Licensees.
Generic Letter 97-03. Washington, DC: NRC. July 1997.
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. NUREG-
1620. Washington DC, June 2003.
NRC. 2008. Standard Format and Content of License Applications for Conventional Uranium
Mills, Draft Regulatory Guide DG-3024, May 2008.
U.S. Nuclear Regulatory Commission, “Environmental Review Guidance for Licensing Actions Associated with NMSS Programs.” NUREG–1748, Washington, DC, 2001.
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.” NUREG-1620, Revision 1, Washington DC, June 2003.
U.S. Nuclear Regulatory Commission, “Regulatory Guide 3.8; Preparation of Environmental Reports for Uranium Mills”, Washington DC, October 1982.
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INTERROGATORY WHITE MESA RECPLAN 07/01: 11E.(2); 10CFR40, APPENDIX A,
CRITERION 6(2); 6(3); 6(4): VERIFY EFFECTIVENESS OF FINAL RADON BARRIER, AND PHASED EMPLACEMENT OF FINAL RADON BARRIER, AND REPORT RADON BARRIER EFFECTIVENESS
REGULATORY BASIS:
UAC R313-24-4 invokes the following requirement from 10CFR40, Appendix A, Criterion 6(2):
“As soon as reasonably achievable after emplacement of the final cover to limit releases of
radon-222 from uranium byproduct material and prior to placement of erosion protection
barriers or other features necessary for long-term control of the tailings, the licensee shall verify through appropriate testing and analysis that the design and construction of the final radon barrier is effective in limiting releases of radon-222 to a level not exceeding 20 pCi/m2s
averaged over the entire pile or impoundment using the procedures described in 40 CFR part 61,
appendix B, Method 115, or another method of verification approved by the Executive Secretary
as being at least as effective in demonstrating the effectiveness of the final radon barrier.”
UAC R313-24-4 invokes the following requirement from 10CFR40, Appendix A, Criterion 6(3):
“When phased emplacement of the final radon barrier is included in the applicable reclamation
plan, the verification of radon-222 release rates required in paragraph (2) of this criterion must
be conducted for each portion of the pile or impoundment as the final radon barrier for that
portion is emplaced.”
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:
Effectiveness of Final Radon Barrier (Refer to Sections 3.3.2 of the Reclamation Plan and
Attachment B, Quality Plan for Construction):
1. Please provide the proposed methods, sets of criteria, type of testing, testing frequency, and
form of documentation that will be used to verify that the design and construction of the final
radon barrier is effective in limiting releases of radon-222 to a level not exceeding 20
pCi/m2s, averaged over the entire pile or impoundment. Indicate that this verification will be completed using procedures described in 40 CFR Part 61, Appendix B, Method 115, or
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another method of verification approved by the Executive Secretary as being at least as
effective in demonstrating the effectiveness of the final radon barrier.
2. Please provide a clear schedule indicating whether the radon barrier layer will be installed in
phases or as a continuous placement of the layer over the tailings management cells area(s),
and provide a schedule for completing radon emissions verification testing that is based on, and clearly tied to, that radon barrier placement schedule.
3. Please provide and submit to for the Division’s review, once the final tailings cover system
design for Revision 4.0 of the Reclamation Plan has been finalized, a map of the disposal
cells area indicating the proposed measurement locations for radon emissions verification testing and the outline of tailings and the radon barrier cover extent. Submittal of such an emissions measurement plan is in conformance with guidance contained in NUREG 1620
(NRC 2003), Section 5.1.2.1. . The emission measurement locations must conform to the
requirements of Method 115 stated in Appendix B to 40 CFR 61 or a comparable method
based on reasonable statistical evaluations of background radon flux measurements and must provide acceptable preliminary measurements of radon flux on the radon barrier, and the required confidence level (refer, for example, to the statistical development defined in
NUREG-1575 [NRC 2000] for sampling contaminated areas).
4. Please provide detailed procedures for conducting radon flux measurements and analyses.
Address in these procedures actions taken and restrictions imposed to ensure that flux measurements are not falsely constrained by transient moisture content of the radon barrier or by failure for radon flux to have equilibrated at the time of measurement.
5. Please provide a plan detailing the method in which records will be maintained, the length of
time records will be maintained and include any associated methods utilized in the
verification of the radon barrier effectiveness.
BASIS FOR INTERROGATORY:
Information regarding the sequencing and durations of reclamation activities, including for the
tailings cells area needs to be provided for final cover closure as a part of the revised Reclamation Plan. The requirement to verify effectiveness of the cover system’s radon barrier by reporting all testing, including methods, analysis, time length and testing outcomes, also
needs to be satisfied as soon as reasonably achievable after emplacement of the final cover, as
required by UAC R3l3-24-4 [10 CFR Part 40, Appendix A, Criterion 6(2)] (see below). and as
described in NUREG-1620 (NRC 2003), Section 5.1.2.1.
DUSA has provided information indicating that the final reclamation of the tailings cells is planned as a phased approach. However, DUSA indicates that the timing of placement of the
final cover over the platform fill will be based on the physical condition of the tailings cell and
management's decision on overall long range mill operations and economics. However, the
Reclamation Plan provides no clear schedule for radon barrier placement (or subsequent verification testing). It is therefore unclear as to the precise sequencing of radon barrier placement for the tailings cells area(s), i.e., placement in distinct phases or placement as a fairly
continuous operation, and the amount of lag time, if any, between completion of any given phase
of radon barrier placement or continuous radon barrier placement and final verification testing of
that placed material. This uncertainty significantly complicates the cost estimates for the surety.
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If the radon barrier layer is placed in phases, UAC R3l3-24-4 [10 CFR Part 40, Appendix A,
Criterion 6(2)] specifies that, as soon as reasonably achievable after emplacement of the final
cover over dewatered tailings licensees need to verify through appropriate testing and analysis
that the design and construction of the final radon barrier is effective in limiting releases of
radon-222 to a level not exceeding 20 pCi/m2s, averaged over the entire pile or impoundment using the procedures described in 40 CFR Part 61, Appendix B, Method 115, or another method
of verification approved by the Executive Secretary as being at least as effective in
demonstrating the effectiveness of the final radon barrier.
NUREG 1620 (NRC 2003), Section 5.1.2.1 indicates that a measured (not calculated) disposal cell average radon flux is required by Appendix A, Criterion 6(2), as soon as practical after placement of the radon barrier, and Criterion 6(3) stipulates that radon-222 release rates must be
verified for each portion of the pile or impoundment as the final radon barrier for that portion is
placed, when phased emplacement of the final radon barrier is included in a reclamation plan.
This section of NUREG-1620 also specifies that the final radon barrier must be placed as expeditiously as practicable, and indicates that a commitment to measure and document the radon flux on the final radon barrier, as required by Criterion 6(2) and (4), should be in the
reclamation plan. (This section of the NRC document also recommends that, before the
measurements are performed, a map of the disposal cell indicating the measurement locations
and outline of tailings and cover extent should be prepared for review before the measurements are performed. This map needs to be prepared and submitted as a part of the preliminary decommissioning plan, mentioned above. .
NUREG-1620 (NRC 2003), Section 5.2.3 specifies that a Reclamation Plan should indicate the
location of records important to decommissioning procedures for protection of health and safety
and demonstrate that decommissioning will be completed as soon as practicable, as required by 10 CFR 40.42 and Appendix A, Criterion 6A.
REFERENCES:
Nuclear Regulatory Commission (NRC) 2000. Multi-Agency Radiation Survey and Site
Investigation Manual (MARSSIM) (NUREG-1575, Revision 1). August 2000.
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.
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INTERROGATORY WHITE MESA RECPLAN 08/01: UAC R313-15-101; RADIATION
SAFETY CONTROLS AND MONITORING
REGULATORY BASIS:
UAC R313-15-101. Radiation Protection Programs. The Utah Uranium Mills and Source Material Tailings Disposal Facility rules [UAC R313-24-1(3)] requires that the provisions of UAC R315-15 apply to these licensees. In turn, UAC R313-15-101 requires:
“(1) Each licensee or registrant shall develop, document, and implement a radiation
protection program sufficient to ensure compliance with the provisions of Rule R313-15.
See Section R313-15-1102 for recordkeeping requirements relating to these programs.
(2) The licensee or registrant shall use, to the extent practical, procedures and engineering controls based upon sound radiation protection principles to achieve occupational doses
and doses to members of the public that are as low as is reasonably achievable (ALARA).
(3) The licensee or registrant shall, at intervals not to exceed 12 months, review the
radiation protection program content and implementation.
(4) To implement the ALARA requirements of Subsection R313-15-101(2), and notwithstanding the requirements in Section R313-15-301, a constraint on air emissions
of radioactive material to the environment, excluding radon-222 and its decay products,
shall be established by licensees or registrants such that the individual member of the
public likely to receive the highest dose will not be expected to receive a total effective dose equivalent in excess of 0.1 mSv (0.01 rem) per year from these emissions. If a licensee or registrant subject to this requirement exceeds this dose constraint, the
licensee or registrant shall report the exceedance as provided in Section R313-15-1203
and promptly take appropriate corrective action to ensure against recurrence.”
INTERROGATORY STATEMENT:
1. Please revise the Reclamation Plan, Rev. 4.0 to address modifications to the radiation protection program necessary to protect site workers, the public, and the environmental from
any unique radiation hazards and effects associated with reclamation and decommissioning
activities. Such revisions to the Reclamation Plan, Rev. 4.0 should address the following:
a. Identify the radiation safety concerns that are unique to reclamation and decommissioning activities. These concerns include characterization of radiation hazards associated with inhalation of resuspended tailings material or yellowcake,
gamma exposure from working close to tailings, and inhalation of radon gas and its
progeny (decay products) emanating from tailings material.
b. Describe any changes to an existing radiation safety or monitoring program that would be necessary to ensure worker or public safety during reclamation or decommissioning activities.
c. Standard dust control measures such as regular wetting and/or phased stabilization to
be used to control windblown tailings material or yellowcake dust.
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d. Any proposed changes to the established bioassay program will meet criteria of the
applicable parts of Regulatory Guide 8.22, “Bioassay at Uranium Mills” and
Regulatory Guide 8.9, Revision 1, “Acceptable Concepts, Models, Equations, and
Assumptions for a Bioassay Program” (NRC, 1993), or an acceptable justification is
provided for selecting an alternate approach.
e. Proposed workplace airborne radiological monitoring program that will support the
proposed bioassay program and is consistent with applicable parts of Regulatory
Guide 8.25, “Air Sampling in the Workplace” and Regulatory Guide 8.30, “Health
Physics Surveys in Uranium Mills,” or an acceptable justification for selecting an alternate approach, if preferred. The monitoring program will provide adequate protection of workers from radon gas or particulate exposures to maintain compliance
with the inhalation limits in 10 CFR Part 20. If sampling locations will be revised, the
reclamation plan contains one or more maps of the site that indicate the location of all
samplers for airborne radiation and provide the justification for determining the revised locations.
f. Proposed contamination control program consistent with the guidance on conducting
surveys for contamination of skin and of personal clothing presented in Regulatory
Guide 8.30.
g. Proposed environmental radiological monitoring program consistent with applicable parts of Regulatory Guide 4.14, “Radiological Effluent and Environmental Monitoring at Uranium Mills”, or an acceptable justification if an alternate approach
if proposed. Demonstrate that site-specific aspects of climate and topography have
been considered in determining locations of off-site airborne monitoring stations and
environmental sampling areas so that detection of maximum off-site concentrations of windblown tailings material and contamination from any other significant transport pathways applicable to the site is ensured.
h. Proposed radiation protection program contains plans for documenting exposures to
all monitored workers and contractors and for availability of exposure records in a
single location for inspection. The program should provide for recordkeeping that meets the requirements of 10 CFR 20.2102; at least annual review of the program content and implementation; and implementation of the “as low as is reasonably
achievable” requirements of 20.1101(d).
BASIS FOR INTERROGATORY:
DUSA should document revisions to the existing radiation protection program that are necessary
to accommodate and protect against the hazards unique to the reclamation and decommissioning
of the mill and associated facilities.
REFERENCES:
Denison Mines (USA) Corporation. 2009. Reclamation Plan, Revision 4.0, White Mesa Mill, Blanding, Utah, November 2009.
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Nuclear Regulatory Commission (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.