DRC-2014-002367 - 0901a06880416601

EN ERG Y FUELS
Energy Fuels Resources (USA) Inc.
225 Union Blvd. Suite 600
Lakewood, CO, US, 80228
303 974 2140
www.energvfuejs.com
Mr. Rusty Lundberg
Director
Division of Radiation Control
March 18, 2014
Sent VIA OVERNIGHT DELIVERY
DRC-2014-002367
Utah Department of Environmental Quality
195 North 1950 West
P.O. Box 144850
Salt Lake City, UT 84114-4820
Re: Transmittal of Source Assessment Report for Sulfate in MW-01 and Total Dissolved Solids in
MW-03A White Mesa Mill Groundwater Discharge Permit UGW370004
Conditional Approval of December 18,2013 Plan and Time Schedule
Dear Mr. Lundberg:
Enclosed are two copies of Energy Fuels Resource (USA) Inc.'s ("EFRI's") Source Assessment Report
("SAR") for Sulfate in MW-01 and Total Dissolved Solids ('TDS") in MW-03A at the White Mesa Mill.
These constituents exceeded their Groundwater Compliance Limits ("GWCLs") in the second and third quarter
of 2013. As required by Part I.G.4(d) of the Groundwater Discharge Permit ("GWDP"), EFRI submitted a Plan
and Time Schedule for the assessment of Sulfate in MW-01 and TDS in MW-03A on December 5, 2013.
Conditional Approval of the Plan and Time Schedule was received by EFRI on December 18, 2013. Pursuant
to the Plan and Time Schedule EFRI has prepared this SAR.
This transmittal also includes two CDs each containing a word searchable electronic copy of the report.
If you should have any questions regarding this report please contact me.
Yours very truly,
ENERGY FUELS RESOURCES (USA) INC.
Kathy Weinel
Quality Assurance Manager
CC: David C. Frydenlund
Harold R. Roberts
David E. Turk
Dan Hillsten
SOURCE ASSESSMENT REPORT FOR
SULFATE IN MW-01 AND TDS IN MW-03A
WHITE MESA URANIUM MILL
Blanding, Utah

Prepared for:
Energy Fuels Resources (USA) Inc.
225 Union Boulevard, Suite 600
Lakewood, CO 80228

Prepared by:
6000 Uptown Boulevard NE, Suite 220
Albuquerque, New Mexico 87110

March 18, 2014

Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A White Mesa Uranium Mill
Blanding, Utah ES-i March 18, 2014
EXECUTIVE SUMMARY
This report is an assessment of the sources, extent, and potential dispersion of sulfate in MW-01
and total dissolved solids (“TDS”) in MW-03A at the White Mesa Uranium Mill. Concentrations
of these constituents have exceeded the applicable Groundwater Compliance Limits (“GWCLs”)
for two consecutive sampling events.
In the October 2012 Source Assessment Report (INTERA, 2012) (“SAR”), EFRI proposed
eliminating GWCLs in upgradient wells MW-01, MW-18, and MW-19 during the next
Groundwater Discharge Permit (“GWDP”) renewal/revision. In a letter from the Director (the
“Director”) of the Utah Division of Radiation Control (“DRC”) dated April 25, 2013, which
includes a memo of the DRC’s review and findings of the October SAR, the DRC approved
removing the GWCLs from upgradient wells in the upcoming GWDP renewal/revision.
However, since the GWDP renewal/revision process is not complete, the sulfate exceedances in
MW-01 were reported to DRC, and this SAR was performed according to the requirements
under Part I.G.4 of the current GWDP. As the results of the geochemical analysis included in this
SAR will demonstrate, sulfate concentrations in upgradient well MW-01 were exhibiting a
significantly increasing trend at the time of the Background Reports. Analysis of the other
indicator parameters confirms that groundwater in MW-01 is not behaving differently than at the
time of the Background Reports, and that the exceedances in sulfate concentrations are consistent
with background groundwater conditions in that well. A revised GWCL has been calculated for
sulfate in MW-01 using the DRC-approved Flowsheet for completeness, although GWCLs will
not be required for MW-01 under the subsequent GWDP.
Results of geochemical analysis for TDS and indicator parameters in far downgradient well
MW-03A show that groundwater in that well is not behaving differently than at the time of the
Background Reports. TDS exhibits a statistically significant increasing trend. This increasing
trend was evident at the time of the Background Reports, however, a smaller data set at that time
and a poor fitting trendline did not allow for a statistically significant determination.
Concentrations of all indicator parameters in MW-03A are exhibiting decreasing trends over time.
Given the recent analyses in the Background Reports and other recent analyses and
investigations at the site, Energy Fuels Resources (USA) Inc. (“EFRI”) believes that exceedances
of the applicable GWCLs for sulfate in MW-01 and TDS in MW-03A are consistent with
background and are likely due to background influences. A revised GWCL is proposed for TDS
in MW-03A in this report.

Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A White Mesa Uranium Mill
Blanding, Utah i March 18, 2014
TABLE OF CONTENTS
EXECUTIVE SUMMARY ........................................................................................................... i
LIST OF TABLES ......................................................................................................................... i
LIST OF FIGURES ....................................................................................................................... i
LIST OF APPENDICES .............................................................................................................. ii
ABBREVIATIONS AND ACRONYMS .................................................................................... iii
1.0 INTRODUCTION............................................................................................................. 1
1.1 Source Assessment Report Layout ......................................................................... 3
2.0 CATEGORIES AND APPROACH FOR ANALYSIS .................................................. 4
2.1 Approach for Analysis ............................................................................................ 4
2.2 Approach for Setting Revised GWCLs ................................................................... 5
2.3 University of Utah Study ........................................................................................ 6
3.0 RESULTS OF ANALYSIS............................................................................................... 8
3.1 Sulfate in MW-01 – Previously Identified Trend ................................................... 8
3.2 TDS in MW-03A – Other Constituents and Wells ................................................. 9
3.3 Proposed Revised GWCLs ................................................................................... 10
4.0 CONCLUSIONS AND RECOMMENDATIONS ........................................................ 11
5.0 REFERENCES ................................................................................................................ 12

LIST OF TABLES
Table 1 Plan and Time Schedules and SARs Previously Submitted or in Progress ............ 2
Table 2 Constituents and Wells Subject to this SAR ........................................................... 3
Table 3 Summary of Findings ............................................................................................ 11
LIST OF FIGURES
Figure 1 White Mesa Mill Site and Groundwater Monitoring Well Location Map

Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A White Mesa Uranium Mill
Blanding, Utah ii March 18, 2014
LIST OF APPENDICES
Appendix A GWCL Exceedances for Fourth Quarter 2013 Under the August 24, 2012
GWDP
Appendix B Geochemical Analysis for Sulfate in MW-01 and TDS in MW-03A B-1 Summary of Geochemical Analysis for Sulfate in MW-01 and TDS in MW-
03A
B-2 Comparison of Calculated and Measured TDS for Samples with Complete
Major Ions B-3 Charge Balance Calculations
B-4 Descriptive Statistics
B-5 Data Used in Statistical Analysis
B-6 Data Omitted from Statistical Analysis
B-7 Box Plots B-8 Histograms
B-9 Linear Regression
B-10 Mann-Kendall Trend Test for Constituents Not Normally or Lognormally
Distributed
Appendix C Geochemical Analysis for Indicator Parameters in MW-01 and MW-03A
C-1 Summary of Geochemical Analysis for Indicator Parameters in MW-01 and
MW-03A
C-2 Descriptive Statistics of Indicator Parameters
C-3 MW-01 and MW-03A Indicator Parameter Data Used in Statistical Analysis
C-4 MW-01 and MW-03A Indicator Parameter Data Omitted from Statistical Analysis
C-5 Box Plots for Indicator Parameters
C-6 Histograms for Indicator Parameters
C-7 Linear Regressions for Lognormally or Normally Distributed Constituents
C-8 Mann-Kendall Trend Test for Constituents Not Normally or Lognormally Distributed
Appendix D Time Concentration Plots Compared to Background Report Plots
Appendix E Flowsheet (Groundwater Data Preparation and Statistical Process Flow for
Calculating Groundwater Protection Standards, White Mesa Mill Site
(INTERA, 2007))
Appendix F Input and Output Files (Electronic Only)

Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A White Mesa Uranium Mill
Blanding, Utah iii March 18, 2014
ABBREVIATIONS AND ACRONYMS
CFCs chlorofluorocarbons
Director Director of the Division of Radiation Control
DRC State of Utah Division of Radiation Control

EFRI Energy Fuels Resources (USA) Inc.
GWCL Groundwater Compliance Limit
GWDP State of Utah Ground Water Discharge Permit UGW370004
GWQS Groundwater Quality Standard

mg/L milligrams per liter Mill White Mesa Uranium Mill

SAR Source Assessment Report

TDS Total Dissolved Solids
USEPA United States Environmental Protection Agency

Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A White Mesa Uranium Mill
Blanding, Utah 1 March 18, 2014
1.0 INTRODUCTION
Energy Fuels Resources (USA) Inc. (“EFRI”) operates the White Mesa Uranium Mill (the
“Mill”) located near Blanding, Utah (Figure 1), under State of Utah Groundwater Discharge
Permit UGW370004 (the “GWDP”). This is the Source Assessment Report (“SAR”) required
under Part I.G.4 of the GWDP relating to violations of Part I.G.2 of the GWDP with respect to
sulfate in groundwater at compliance monitoring well MW-01 and total dissolved solids (“TDS”)
in groundwater at compliance monitoring well MW-03A (Figure 1).
Part I.G.2 of the GWDP provides that out-of-compliance status exists when the concentration of
a constituent in two consecutive samples from a compliance monitoring point exceeds a
groundwater compliance limit (“GWCL”) in Table 2 of the GWDP. The GWDP was originally
issued in March 2005, at which time GWCLs were set on an interim basis, based on fractions of
State of Utah Ground Water Quality Standards (“GWQSs”) or the equivalent, without reference
to natural background at the Mill site. The GWDP also required that EFRI prepare a background
groundwater quality report to evaluate all historical data for the purposes of establishing
background groundwater quality at the site and developing GWCLs under the GWDP. As
required by then Part I.H.3 of the GWDP, EFRI submitted the following to the Director (the
“Director”) of the Utah Division of Radiation Control (“DRC”) (the Director was formerly the
Executive Secretary of the Utah Radiation Control Board and the Co-Executive Secretary of the
Utah Water Quality Board):
• A Revised Background Groundwater Quality Report: Existing Wells for Denison Mines
(USA) Corp.’s Mill Site, San Juan County, Utah, October 2007, prepared by INTERA,
Inc. (the “Existing Wells Background Report”).
• A Revised Addendum: Evaluation of Available Pre-Operational and Regional
Background Data, Background Groundwater Quality Report: Existing Wells for Denison
Mines (USA) Corp.’s Mill Site, San Juan County, Utah, November 16, 2007, prepared by
INTERA, Inc. (the “Regional Background Report”).
• A Revised Addendum: Background Groundwater Quality Report: New Wells for
Denison Mines (USA) Corp.’s Mill Site, San Juan County, Utah, April 30, 2008,
prepared by INTERA, Inc. (the “New Wells Background Report,” and together with the
“Existing Wells Background Report” and the “Regional Background Report,” the
“Background Reports”).
Based on a review of the Background Reports and other information and analyses, the Director re-
opened the GWDP and modified the GWCLs to be equal to the mean concentration plus two
standard deviations or the equivalent. The modified GWCLs became effective on January 20, 2010.

Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A White Mesa Uranium Mill
Blanding, Utah 2 March 18, 2014
Table 1 lists previously submitted Plan and Time Schedules with corresponding SARs in
accordance with the GWDP.
Table 1
Plan and Time Schedules and SARs Previously Submitted or in Progress
Quarter Plan and Time Schedule Date SAR Date
Q1 2010, Q2 2010,
Q3 2010, Q4 2010, Q1 2011 June 13, 2011 October 10, 2012
Q2 2011 September 7, 2011 October 10, 2012
Q3 2012 December 13, 2012 May 7, 2013
Q4 2012 March 15, 2013 August 30, 2013
Q1 2013 August 27, 2013 December 17, 2013
Q2 2013 September 20, 2013 January 14, 2014
Q3 2013 December 5, 2013 March 18, 2014

In the October 2012 SAR, EFRI proposed eliminating GWCLs in upgradient wells MW-01,
MW-18, and MW-19 during the next GWDP renewal/revision. In a letter from the Director dated
April 25, 2013, DRC approved removal of the GWCLs at MW-01 stating:
DRC agrees with the justifications provided by EFR, that far-up gradient wells
are not likely to be impacted by current Mill activities…
Specifically, DRC justifications to allow removal of GWCL’s at wells MW-1,
MW-18 and MW-19 are as follows:
1. Per DRC review of water elevation maps and expected groundwater flow directions, wells MW-1, MW-18, and MW-19 are hydraulically upgradient from the Mill,
2. Groundwater monitoring for all currently monitored parameters listed on
Table 2 of the permit will continue at baseline monitoring frequencies and will be submitted with the Mill Quarterly Ground Water Monitoring Reports,
3. Continuation of GWCL’s at upgradient monitoring wells may result in unnecessary enforcement action and source assessment.
On November 15, 2013, EFRI submitted a notice (the “Third Quarter 2013 Exceedance Notice”)
to the Executive Secretary under Part I.G.1(a) of the GWDP providing notice that sulfate
concentrations in MW-01 and TDS concentrations in MW-03A had exceeded the GWCL for two
consecutive sampling events. A Plan and Time Schedule for the third quarter of 2013 (“Q2 2013
Plan and Time Schedule”) addressing sulfate in MW-01 and TDS in MW-03A was submitted on
December 5, 2013, and approved by DRC in correspondence dated December 18, 2013. This

Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A White Mesa Uranium Mill
Blanding, Utah 3 March 18, 2014
SAR addresses sulfate in MW-01 and TDS in MW-03A as described in the DRC-approved Q3
2013 Plan and Time Schedule.
Table 2
Constituents and Wells Subject to this SAR
Constituent Well Monitoring Event GWCL (mg/L) Result (mg/L)
Sulfate MW-01 Q2 2013
Q3 2013 838 839
911
TDS MW-03A Q2 2013
Q3 2013 5,805 6,020
5,860
mg/L = milligrams per liter
Since the GWDP renewal/revision process is not complete, the sulfate exceedances in MW-01
were reported to DRC as described above, and this SAR was performed according to the
requirements under Part I.G.4 of the current GWDP.
1.1 Source Assessment Report Layout
This SAR follows a similar format to the October 2012 SAR and all SARs submitted thereafter.
A description of the approach used for analysis is provided in Section 2.0, and the results of the
analysis are presented in Section 3.0. Conclusions and recommendations are reviewed in
Section 4.0, and references are included in Section 5.0.
The appendices consist of the analyses performed for this assessment and are organized in the
following manner: Appendix A contains a table showing exceedances in groundwater
monitoring wells at the Mill. Appendix B contains the geochemical analysis performed on
sulfate in MW-01 and TDS in MW-03A. Appendix C contains the indicator parameter analysis
performed on groundwater concentrations of chloride, fluoride, sulfate, and uranium in MW-01
and MW-03A. Appendix D contains data plots for out-of-compliance and indicator parameters
in MW-01 and MW-03A using all available data to date compared to the data plots from the
Background Reports. Appendix E contains the Flowsheet developed based on the United States
Environmental Protection Agency’s (“USEPA”) Statistical Analysis of Groundwater Monitoring
Data at RCRA Facilities, Unified Guidance (USEPA, 2009), and was approved by DRC prior to
completion of the Background Reports. Appendix F is included on the compact disc that
accompanies this SAR and contains the electronic input and output files used for statistical
analysis.

Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A White Mesa Uranium Mill
Blanding, Utah 4 March 18, 2014
2.0 CATEGORIES AND APPROACH FOR ANALYSIS
Generally, out-of-compliance constituents and wells can be grouped into five categories:
1. Constituents in wells with previously identified rising trends.
2. Constituents in pumping wells.
3. Constituents potentially impacted by decreasing trends in pH across the site.
4. Newly installed wells with interim GWCLs.
5. Other constituents and wells.
This SAR addresses sulfate in MW-01 and TDS in MW-03A, which fall under categories one
and five, respectively. Sulfate in MW-01 was identified as having a statistically significant
increasing trend at the time of the Background Reports (INTERA, 2007). TDS does not fall
under any of the first four categories, and therefore is under the fifth category, “other
constituents.”
2.1 Approach for Analysis
The first step in the analysis is to perform an assessment of the potential sources for each
exceedance to determine whether the exceedance is due to background influences or Mill
activities. If an exceedance is determined to be caused by background influences, then it is not
necessary to perform any further evaluations on the extent and potential dispersion of the
contamination or to perform an evaluation of potential remedial actions. Monitoring will
continue, and where appropriate, revised GWCLs are proposed to reflect changes in background
conditions at the site.
The assessment for potential sources for each exceedance was accomplished by performing a
geochemical analysis to evaluate the behavior of the constituents in the well in question to
determine if there have been any changes in the behavior of indicator parameters, such as
chloride, sulfate, fluoride, and uranium, since the date of the Background Reports that may
suggest a change in the behavior of that well.
As discussed in detail in Section 9.0 of the Existing Wells Background Report, chloride is the
best indicator of potential tailings cell leakage, followed by fluoride, then sulfate (due to mobility
and abundance in tailings). Uranium is probably the most mobile of trace (metal) elements and is
the best indicator parameter for metals and radionuclides. A monitoring well impacted by any
potential seepage from tailings impoundments would be expected to exhibit rising concentrations
of chloride and possibly fluoride, sulfate, and uranium. However, while uranium may be the
most mobile of trace (metal) elements, it is typically retarded behind chloride and would likely

Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A White Mesa Uranium Mill
Blanding, Utah 5 March 18, 2014
not be expressed in groundwater until sometime after chloride concentrations had begun to rise.
This is because uranium is a metal cation and behaves as other metals with respect to pH. It is
important to note, however, that while a lack of a rising trend in chloride would indicate that
there has been no impact from tailings, a rising trend in chloride could also be due to some
natural influences (see Section 12.0 of the Existing Wells Background Report). Therefore, in
situations where there is a significant rising trend in chloride, other evaluations would need to be
performed, such as a determination as to whether any other indicator parameters have
demonstrated a significant rising trend and whether or not the concentrations and mass balance
indicate a potential tailings cell leak.
The geochemical analysis was supported by a statistical analysis that followed the process
outlined in the Groundwater Data Preparation and Statistical Process Flow for Calculating
Groundwater Protection Standards, White Mesa Mill Site, San Juan County, Utah (Flowsheet)
(INTERA, 2007), a copy of which is attached as Appendix E. The Flowsheet was designed
based on USEPA’s Statistical Analysis of Groundwater Monitoring Data at RCRA Facilities,
Unified Guidance (USEPA, 2009), and was approved by DRC prior to completion of the
Background Reports.
In this analysis, concentrations of sulfate in MW-01 and TDS in MW-03A were found to be
consistent with background conditions, eliminating the need for additional hydrological or
geochemical (mass balance) analysis, while emphasizing the need for revised GWCLs due to the
changing conditions at the site.
2.2 Approach for Setting Revised GWCLs
If the foregoing approaches result in the conclusion that the previous analysis in the Background
Reports has not changed and that the out-of-compliance status of a constituent in a well is due to
natural influences, then, except in the case of MW-01, a proposed new GWCL was proposed. In
proposing revised GWCLs, we have adopted the approach in the Flowsheet.
As presented in the October 2012 SAR, EFRI proposed, and DRC subsequently agreed, to
modify the requirements of the upcoming GWDP to continue sampling but eliminate GWCLs in
upgradient wells MW-01, MW-18, and MW-19. Since the GWDP renewal/revision process is
not complete, a revised GWCL for sulfate has been calculated according to the Flowsheet and
the current GWDP. This GWCL is included for completeness, although GWCLs will not be
required for MW-01 under the subsequent GWDP.
Appendix B-1 summarizes the revised GWCLs for the out-of-compliance constituents listed in
Table 2 based on an application of the Flowsheet. A revised GWCL for MW-01 is included on
that table for completeness and to show recalculated GWCLs based on the Flowsheet.

Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A White Mesa Uranium Mill
Blanding, Utah 6 March 18, 2014
It is assumed that once revised GWCLs are set for the various constituents, accelerated
monitoring for those constituents will cease.
2.3 University of Utah Study
At the request of DRC, T. Grant Hurst and D. Kip Solomon of the Department of Geology and
Geophysics of the University of Utah performed a groundwater study (the “University of Utah
Study”) at the Mill site in July 2007 to characterize groundwater flow, chemical composition,
noble gas composition, and age (Hurst and Solomon, 2008) to determine whether or not the
increasing and elevated trace metal concentrations in monitoring wells at the Mill site, all of
which were identified in the Background Reports, may indicate that potential leakage from
tailings cells is occurring.
In order to evaluate sources of solute concentrations at the Mill site, low-flow groundwater
sampling was implemented in 15 monitoring wells, including MW-03A. In addition, surface
water samples were collected from tailings cells 1, 3, and 4A, and two wildlife ponds. Passive
diffusion samplers were also deployed and collected in order to characterize the dissolved gas
composition of groundwater at different depths within the wells. Samples were collected and
analyzed for the following: tritium, nitrate, sulfate, deuterium and oxygen-18 of water, sulfur-34
and oxygen-18 of sulfate, trace metals (uranium, manganese, and selenium), and
chlorofluorocarbons (“CFCs”).
Hurst and Solomon concluded generally that “[t]he data show that groundwater at the Mill is
largely older than 50 years, based on apparent recharge dates from chlorofluorocarbons and
tritium concentrations. Wells exhibiting groundwater that has recharged within the last 50 years
appears to be a result of recharge from wildlife ponds near the site. Stable isotope fingerprints
do not suggest contamination of groundwater by tailings cell leakage, evidence that is
corroborated by trace metal concentrations similar to historically-observed observations.” (Hurst
and Solomon, 2008, page iii)
Specific observations with respect to MW-03A include:
• MW-03A exhibited recharge dates of the late 1980s, but Solomon and Hurst concluded
that MW-03A was “pumped dry . . . because of low-yielding characteristics, and well
MW-3A was subsequently sampled using [EFRI] dedicated bladder pumps. Potential
CFC contamination could have occurred in these wells, as well as MW-3, because of
exposure to atmosphere after pumping the boreholes dry.” (Hurst and Solomon, 2008,
page 23)

Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A White Mesa Uranium Mill
Blanding, Utah 7 March 18, 2014
• Tritium concentrations in MW-03A were found to be non-detect, indicating that impacts
from wide-scale atmospheric injection of tritium during above-ground thermonuclear
weapons testing in the 1950s and 1960s, expected to be found in surface waters such as
Mill tailings, were not observed in that well.
• Hurst and Solomon also concluded MW-03A has more depleted ð18O and elevated
uranium concentrations, but as they do not bear an evaporated stable isotope signal, it
does not appear that the elevated uranium values are the result of leakage from tailing
cells (or wildlife ponds) (Hurst and Solomon, 2008, page 44).

Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A White Mesa Uranium Mill
Blanding, Utah 8 March 18, 2014
3.0 RESULTS OF ANALYSIS
This section describes the results of the analyses by category. Summaries of the analyses are
provided in Appendix B-1, Appendix C-1, and Appendix D.
3.1 Sulfate in MW-01 – Previously Identified Trend
Sulfate concentrations in MW-01 have exceeded the current GWCL (Table 2). DRC has agreed
that MW-01 is located far enough upgradient from the Mill facility and tailings cells that it is
extremely unlikely to be impacted if there were potential groundwater impacts at the site based
on review of water level data which indicate that groundwater elevations in MW-01 are higher
than the groundwater elevations in monitoring wells completed in the Burro Canyon aquifer
beneath the Mill’s tailings cells. DRC has agreed that MW-01 should not be subject to GWCLs
due to the fact that MW-01 is located upgradient of the tailings cells; however, MW-01 is subject
to GWCLs until the GWDP has been renewed/revised. When the GWDP is renewed/revised,
MW-01 will continue to be monitored on a routine frequency, but will not be subject to
compliance requirements.
Geochemical analysis was performed on sulfate concentrations in MW-01. This analysis
included performing the data quality controls and statistical analysis as presented in the
Flowsheet. The analysis also included a comparison of the complete data set to date (through
fourth quarter 2013) to the data set available at the time of the Background Reports. This
comparison shows that both data sets are not normally or lognormally distributed and exhibit
statistically significant increasing trends in concentrations of sulfate over time.
Concentrations of indicator parameters in MW-01 were subject to a similar geochemical analysis
to determine if the behavior of the well has changed since the time of the Background Reports.
Indicator parameters were analyzed using the Flowsheet method, and were also compared to
analysis of indicator parameters at the time of the Background Reports. A summary of this
analysis is presented in Appendix C-1. Appendix D contains data plots of indicator parameters
now and at the time of the Background Reports. Chloride is showing a statistically significant
increasing trend. This trend was apparent at the time of the Background Reports; however, it was
not statistically significant. Fluoride concentrations are showing a slightly decreasing trend,
which was apparent at the time of the Background Reports. Uranium concentrations are
exhibiting a statistically significant decreasing trend, which was identified at the time of the
Background Reports. The results of the indicator parameter analysis supports the conclusions of
previous studies and the agreement between EFRI and DRC that groundwater in MW-01 is
behaving consistently with background conditions and is not being affected by potential Mill
activities.

Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A White Mesa Uranium Mill
Blanding, Utah 9 March 18, 2014
If MW-01 were to continue as a compliance well, EFRI would recommend revising the GWCL
based on all available data to date. Since the designation of MW-01 will be changed from
compliance well to monitoring well, revised GWCLs are not necessary; however, a revised
GWCL for sulfate in MW-01 calculated using the Flowsheet is included in Appendix B-1 for
completeness.
3.2 TDS in MW-03A – Other Constituents and Wells
TDS concentrations have been out of compliance in far downgradient well MW-03A (Table 2).
Geochemical evaluation of TDS in MW-03A comparing the current, complete data sets for TDS
and indicator parameters shows that groundwater behavior in MW-03A has not changed since
the time of the Background Reports. Additionally, concentrations of indicator parameters in
MW-03A are exhibiting decreasing trends when plotted over time (Appendix D). At the time of
the New Wells Background Report, MW-03A was a relatively new well with eight or nine
sample results available, which is the minimum number of results necessary to perform the
Flowsheet analysis.
MW-03A is located approximately 2,000 feet downgradient from the Mill’s tailings cells. It is
extremely unlikely that any potential tailings cell leakage could reach MW-03A during the
30 years that the Mill has been in operation. As indicated in Section 4.2 of HGC (2012a), travel
times in the perched aquifer at the Mill are estimated to be 0.9 feet per year in the area between
the Mill’s tailings cells and MW-03A, resulting in a travel time of over 2,000 years from the
tailings cells to MW-03A. Even if potential tailings cell leakage could have reached MW-03A in
the 30 years of Mill operations, a rising trend in chloride would be observed before any other
individual constituents would be impacted in that well, and as the results of the geochemical and
indicator parameter evaluation show, there is not an increasing trend in chloride in MW-03A.
Further, as discussed above, MW-03A was included in the University of Utah Study, where
Hurst and Solomon (2008) concluded that “[s]table isotope fingerprints do not suggest
contamination of groundwater by tailings cell leakage, evidence that is corroborated by trace
metal concentrations similar to historically-observed observations.”
The exceedance of TDS can therefore be attributed to natural background variation, and likely
the small data set used to establish GWCLs at the time of the Background Reports. We can
therefore conclude that the exceedances of TDS in MW-03A have not been caused by Mill
operations and recommend revision the GWCL for TDS in MW-03A based on all available data
to date.

Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A White Mesa Uranium Mill
Blanding, Utah 10 March 18, 2014
3.3 Proposed Revised GWCLs
The results of the geochemical analysis support the conclusions that exceedances of sulfate in
MW-01 and TDS in MW-03A are consistent with background groundwater conditions at each
well. Therefore revised GWCLs have been calculated and are proposed as follows:
• The current GWCL for sulfate in MW-01 is 838 mg/L. The revised GWCL using all
available data to date is 846 mg/L, which was determined by using the highest historical
value in accordance with the Flowsheet, after extreme outliers have been removed. This
revised value has already been exceeded by the third and fourth quarter 2013 sampling
results of 911 and 930 mg/L, respectively. Following the steps of the Flowsheet, these
two results were filtered out of the data set prior to analysis during the box plot and
extreme outlier identification. Therefore the revised GWCL is not appropriate for
compliance in this well. This revised GWCL, determined by following the steps in the
Flowsheet, is included in this SAR for completeness. As discussed in Section 1.0,
upgradient well MW-01 will not be subject to GWCLs after the upcoming GWDP
renewal/revision.
• The current GWCL for TDS in MW-03A is 5,805 mg/L. The revised GWCL using all
available data to date is 6,028 mg/L, which was calculated using the mean plus two
standard deviations in accordance with the Flowsheet.
EFRI maintains that GWCLs for constituents in wells with significantly increasing trends that
are the result of background influences, such as sulfate in MW-01 and TDS in MW-03A, should
be revised regularly, as is recommended by USEPA’s Unified Guidance (USEPA, 2009), to
account for the trends and to minimize unwarranted out-of-compliance status in such wells.
As presented above, the revised GWCL for sulfate in MW-01 has already been exceeded twice
as shown by the third and fourth quarter 2013 sampling results, and the exceedance of TDS in
the second quarter of 2013 (6,020 mg/L) is only 8 mg/L less than the revised GWCL of
6,028 mg/L. Since the concentrations of sulfate in MW-01 and TDS in MW-03A are and always
have been exhibiting increasing trends, this circumstance reinforces the need for a compliance
solution for constituents in wells that are exhibiting increasing trends due to natural background
conditions.
EFRI is currently in the planning and development stage for proposing an alternative method of
compliance for constituents in wells with increasing trends that are caused by background
conditions at the Mill site.

Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A White Mesa Uranium Mill
Blanding, Utah 11 March 18, 2014
4.0 CONCLUSIONS AND RECOMMENDATIONS
Background at the Mill site was recently thoroughly studied in the Background Reports and in
the University of Utah Study. Both the Background Reports and the University of Utah Study
concluded that groundwater at the site has not been impacted by Mill operations. Both of those
studies also acknowledged that there are natural influences at play at the site that have given rise
to increasing water trends and general variability of background groundwater at the site.
The focus of this SAR was therefore to identify any changes in the circumstances identified in
those studies. A geochemical analysis of sulfate in MW-01 and TDS in MW-03A and their
respective indicator parameters was performed.
The results of the analyses show that there has not been a significant change in the behavior of
groundwater in MW-01 and MW-03A, which means that the exceedances observed at the Mill
site in these wells are the result of natural background influences.
Table 3
Summary of Findings
Well Out-of-Compliance
Constituent Summary Path Forward
MW-01 Sulfate Far upgradient. Previously identified
increasing trend. Consistent with background conditions.
Revise GWCL until subsequent
GWDP is approved by DRC.
MW-03A TDS Far downgradient. No significantly
increasing trends in indicator parameters. Consistent with
background conditions.
Revise GWCL until alternate
method of compliance for constituents with increasing
trends that are not due to potential mill activity is approved
by DRC.

As the results of the geochemical analysis demonstrate, each exceedance can be attributed to
natural background. Revised GWCLs have been calculated for both Sulfate in MW-01 and TDS
in MW-03A; however, MW-01 will not be subject to GWCLs after the upcoming GWDP
revision/renewal.
The revised GWCL for TDS in MW-03A that is currently being proposed may change after
EFRI and DRC agree on an alternate method of compliance for constituents in wells with
increasing trends that can be attributed to background conditions. EFRI is currently in the
planning and development stage for proposing an alternative method of compliance for
constituents in wells with increasing trends that are caused by background conditions at the site.

Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A White Mesa Uranium Mill
Blanding, Utah 12 March 18, 2014
5.0 REFERENCES
White Mesa Uranium Mill Nitrate Monitoring Reports, 2009-2012.
Hydro Geo Chem (HGC), 2012a. Site Hydrology and Estimation of Groundwater Travel Times in the Perched Zone, White Mesa Uranium Mill Site Near Blanding, Utah. Prepared for
Denison Mines (USA) Corp. by Hydro Geo Chem Inc., July 10, 2012.
Hurst, T.G., and Solomon, D.K., 2008. Summary of Work Completed, Data Results,
Interpretations and Recommendations for the July 2007 Sampling Event at the Denison Mines, USA, White Mesa Uranium Mill Near Blanding Utah. Prepared by Department of Geology and Geophysics, University of Utah.
INTERA Incorporated, 2007. Revised Background Groundwater Quality Report: Existing Wells
for Dension Mines (USA) Corp.’s White Mesa Uranium Mill Site, San Juan County,
Utah.
______. 2012 Source Assessment Report
USEPA, 2009. Statistical Analysis of Groundwater Monitoring Data at RCRA Facilities EPA
530/R-09-007.

FIGURE

Cell No. 1
Cell No. 2
Cell No. 3
Cell No. 4A
W i l d l i f e P o n d
W i l d l i f e P o n d

Mill Site
Cell No. 4B
MW-37
MW-36
MW-35
MW-34MW-33
MW-32MW-31
MW-30
MW-29
MW-28
MW-27
MW-26
MW-25
MW-24
MW-23
MW-22
MW-21
MW-20
MW-19
MW-18
MW-17
MW-15
MW-14
MW-12
MW-11
MW-05
MW-04
MW-03
MW-02
MW-01
MW-03A
S : \ P r o j e c t s \ I U C - 0 0 1 - 0 1 - 0 0 1 D e n i s o n M i n e s \ G I S \ m a p d o c s \ 2 0 1 3 _ S A R s \ M W - 1 _ M W - 3 A _ M a r 2 0 1 4 \ F i g 0 1 _ L o c M a p _ M W 1 _ M W 3 A . m x d D a t e : 3 / 6 / 2 0 1 4
F i g u r e 1 L o c a t i o n o f W h i t e M e s a U r a n i u m M i l l a n d M o n i t o r i n g W e l l s S o u r c e A s s e s s m e n t R e p o r t f o r S u l f a t e i n M W - 0 1 a n d T D S i n M W - 0 3 A
1 , 0 0 0 0 1 , 0 0 0 5 0 0
F e e t
S o u r c e ( s ) : A e r i a l N A I P U t a h 2 0 1 1 ; W e l l s H G C , I n c . , M a y 2 0 0 8 r e p o r t .
L e g e n d
G r o u n d w a t e r M o n i t o r i n g W e l l s
U T A H U T A H
W h i t e M e s a U r a n i u m M i l l

APPENDIX A
GWCL Exceedances for Fourth Quarter 2013
Under the August 24, 2012 GWDP
APPENDIX A
GWCL Exceedances for Fourth Quarter 2013 Under the August 24, 2012 GWDP
Page 1 of 8
Appendix A
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
Monitoring Well
(Water Class)
Constituent Exceeding
GWCL
GWCL in
August 24, 2012 GWDP
Q1 2010
Sample Date
Q1 2010
Result
Q2 2010
Sample Date
Q2 2010
Result
May 2010
Monthly Sample Date
May 2010
Monthly Result
June 2010
Monthly Sample Date
June 2010
Monthly Result
July 2010
Monthly Sample Date
July 2010
Monthly Result
August 2010
Monthly Sample Date
August 2010
Monthly Result
Q3 2010
Sample Date
Q3 2010
Result
October 2010
Monthly Sample Date
October 2010
Monthly Result
Q4 2010
Sample Date
Q4 2010
Result
December 2010
Monthly Sample Date
December 2010
Monthly Result
Field pH (S.U.)6.5 - 8.5 7.34 7.22 7.29 8.21 7.51 7.32 8.34 7.49 7.44 7.37
Manganese (ug/L)131.29 134 137 122 99 123 138 128 141 133 158
Manganese (ug/L)2230.30 2060 2070 NA NA NA NA 1920 NA 1980 NA
Field pH (S.U.)6.5 - 8.5 6.45 6.29 6.36 6.45 7.19 6.48 6.51 6.60 6.37 6.47
Field pH (S.U.)6.5 - 8.5 6.53 7.2 NA NA NA NA 6.58 NA 6.36 NA
Cadmium (ug/L)1.5 1.26 1.44 NA NA NA NA 1.4 NA 1.26 NA
Chloride (mg/L)35 31 31 NA NA NA NA 31 NA 31 NA
Fluoride (mg/L)0.42 0.31 0.33 NA NA NA NA 0.34 NA 31 NA
Uranium 6.5 5.93 6.43 NA NA NA NA 6.57 NA 5.89 NA
Nitrate + Nitrite (as N) (mg/L)0.62 1.3 2 0.3 0.4 0.6 0.6 0.7 0.4 0.2 0.4
Uranium (ug/L)41.8 58.7 66.7 37.4 36.6 34.4 71.8 72.7 37.5 30.4 29.6
Chloroform (ug/L)70 700 1700 800 940 900 2800 2100 1000 1900 1400
Chloride (mg/L)58.31 72 57 80 47 52 49 64 52 48 52
Field pH (S.U.)6.74 - 8.5 6.59 7.18 6.36 6.98 6.45 6.39 6.60 6.61 6.49 6.45
Dichloromethane (Methylene
Chloride) (ug/L)5 1 9.9 NR 2.2 12 24 45 5.5 16 1.2
Nitrate + Nitrite (as N) (mg/L)2.5 16.1 15.8 17 15.3 7/21/2010 16 8/24/2010 16 15 15 15 16
Chloride (mg/L)128 127 97 NS NS NS NS NS NS 111 NS 126 NS
Uranium (ug/L)8.32 6.82 6.82 NS NS NS NS NS NS 7.10 NS 6.64 NS
Selenium (ug/L)34 32 35.3 NS NS 7/27/2010 33.5 8/24/2010 35.6 32.6 32.4 32.2 30.5
Nitrate + Nitrite (as N) (mg/L)5 21.7 22.5 5/21/2010 23 6/15/2010 21.1 7/21/2010 20 8/24/2010 22 21 10/19/2010 20 20 20
TDS (mg/L)1320 1150 1220 NS NA NS NA NS NA NS NA 1330 NS NA 1320 NS
Chloride (mg/L)143 128 128 NS NA NS NA NS NA NS NA 139 NS NA 138 NS
Selenium (ug/L)71 60.8 59.6 NS NA NS NA NS NA NS NA 64.4 NS NA 60 NS
Field pH (S.U.)6.5 - 8.5 6.96 7.38 5/21/2010 6.95 6/15/2010 7.01 7/21/2010 7.80 8/24/2010 7.10 7.66 (7.13)10/19/2010 6.92 6.98 6.95
Sulfate (mg/L)532 507 522 NS NA NS NA NS NA NS NA 527 NS NA 539 NS
Manganese (ug/L)200 NA NA NA NA NA NA NA NA 698 NA
Thallium (ug/l)0.5 NA NA NA NA NA NA NA NA 1.14 NA
Molybdenum (ug/L)10 NA NA NA NA NA NA NA NA <10 NA
Gross Alpha minus Rn & U (pCi/L)3.75 NA NA NA NA NA NA NA NA 2.6 NA
Selenium (ug/L)12.5 NA NA NA NA NA NA NA NA ND NA
Uranium (ug/L)7.5 NA NA NA NA NA NA NA NA 27.2 NA
Manganese (ug/L)289 NA 212 NA NA NA NA NA NA 275 NA
Tetrahydrofuran (ug/L)11.5 NA 7.8 NA NA NA NA NA NA 10.7 NA
Sulfate (mg/L)838 NA 805 NA NA NA NA NA NA 792 NA
Selenium (ug/L)37 NA 37.2 NA NA NA NA 35.5 NA 38.8 NA
Field pH (S.U.)6.5 - 8.5 NA 6.14 (6.25)NA NA NA NA 6.39 NA 6.35 NA
Sulfate (mg/L)3663 NA 3490 NA NA NA NA NA NA 3430 NA
Nitrate + Nitrite (as N) (mg/L)0.73 NA 0.3 NA NA NA NA NA NA 0.4 NA
Fluoride (Mg/L)0.68 NA 0.71 NA NA NA NA 0.63 NA 0.77 NA
Field pH (S.U.)6.5 - 8.5 NA 6.23 (6.24)NA NA NA NA 6.42 NA 6.21 NA
Sulfate (mg/L)3640 NA 3680 NA NA NA NA 3630 NA 3850 NA
Nitrate + Nitrite (as N) (mg/L)1.3 NA 1.0 NA NA NA NA NA NA 1.2 NA
TDS (mg/L)5805 NA 5860 NA NA NA NA 5470 NA 5330 NA
Selenium (ug/L)89 NA 81.4 NA NA NA NA NS NA 94.8 NA
MW-05 (Class II)Uranium (ug/L)7.5 NS NA 4/26/2010 0.39 NS NA NS NA NS NA NS NA NS NA NS NA 11/11/2010 11.6 NS NA
Required Quarterly Sampling Wells
Q1 2010 Results Q2 2010 Results Q3 2010 Results Q4 2010 Results
11/11/2010 12/15/10MW-11 (Class II)2/10/2010 4/28/2010 5/24/2010 6/16/2010 7/20/2010 8/25/2010 9/8/2010 10/20/2010
9/8/2010 10/20/2010
NS NS NS NS NS
11/10/2010 12/15/2010
9/8/2010 11/10/2010
NS
9/20/2010 11/19/2010
NS
NS
11/9/2010 12/14/2010
MW-31 (Class III) 2/9/2010 4/20/2010 9/13/2010
(9/21/10)11/9/2010 12/14/2010
NS
NS
NS
NS
NS
NS
NS 11/18/2010
MW-03A (Class III)5/4/2010
MW-01 (Class II)5/5/2010 NS
NS 9/21/2010 11/22/2010
NS NS
NS NS NS
NS
NS
NS
Required Semi-Annual Sampling Wells
MW-03 (Class III)5/3/2010
NS
NS
11/30/2010
6/16/2010 7/20/2010 8/25/2010
MW-35 (Class II)NS NS NS NS NS NS
MW-26 (Class III)2/2/2010 4/22/2010 5/21/2010 6/16/2010 7/21/2010 8/16/2010
MW-25 (Class III) 2/3/2010 4/28/2010
MW-30 (Class II)2/9/2010 4/27/2010 5/21/2010 6/15/2010
NS
MW-14 (Class III)2/2/2010 4/21/2010 5/21/2010
NSNS
9/26/2010 10/20/2010
9/14/2010 10/19/2010
11/15/2010 12/15/2010
APPENDIX A
GWCL Exceedances for Fourth Quarter 2013 Under the August 24, 2012 GWDP
Page 2 of 8
Appendix A
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
Monitoring Well
(Water Class)
Constituent Exceeding
GWCL
GWCL in
August 24, 2012 GWDP
Q1 2010
Sample Date
Q1 2010
Result
Q2 2010
Sample Date
Q2 2010
Result
May 2010
Monthly Sample Date
May 2010
Monthly Result
June 2010
Monthly Sample Date
June 2010
Monthly Result
July 2010
Monthly Sample Date
July 2010
Monthly Result
August 2010
Monthly Sample Date
August 2010
Monthly Result
Q3 2010
Sample Date
Q3 2010
Result
October 2010
Monthly Sample Date
October 2010
Monthly Result
Q4 2010
Sample Date
Q4 2010
Result
December 2010
Monthly Sample Date
December 2010
Monthly Result

Q1 2010 Results Q2 2010 Results Q3 2010 Results Q4 2010 Results
Field pH (S.U.)6.5 - 8.5 NA 7.16 NA NA NA NA 6.62 NA 6.47 NA
Selenium (ug/L)25 NA 25.7 NA NA NA NA 31.9 NA 27.6 NA
Selenium (ug/L)128.7 NA 100 NA NA NA NA NA NA 99.5 NA
Field pH (S.U.)6.62 - 8.5 NA 6.98 NA NA NA NA NA NA 6.57 NA
Iron (ug/L)81.7 NA ND NA NA NA NA NA NA ND NA
Thallium (ug/l)1.95 NA 3.73 NA NA NA NA 3.64 NA 3.57 NA
Sulfate (mg/L)1938.9 NA 1950 NA NA NA NA 1930 NA 1910 NA
Field pH (S.U.)6.25-8.5 NA 6.2 NA NA NA NA 7.23 NA 6.37 NA
TDS (mg/L)3198.77 NA 3280 NA NA NA NA 3190 NA 3030 NA
Field pH (S.U.)6.78-8.5 NA 6.61 (6.66)NA NA NA NA 6.93 NA 6.8 NA
Gross Alpha minus Rn & U
(pCi/L)2.36 NA 0.9 NA NA NA NA NA NA 1.2 NA
Nitrate + Nitrite (as N) (mg/L)2.83 NA 2.6 NA NA NA NA NA NA 2.4 NA
Field pH (S.U.)6.5 - 8.5 NA 6.18 NA NA NA NA 7.05 NA 6.44 NA
Manganese (ug/L)550 NA 184 NA NA NA NA NS NA 65 NA
Cadmium (ug/L)2.5 NA 4.28 NA NA NA NA 5.06 NA 3.22 NA
Fluoride (Mg/L)0.36 NA 0.14 NA NA NA NA NA NA 0.18 NA
Thallium (ug/L)1 NA 1.3 NA NA NA NA 1.57 NA 1.09 NA
Field pH (S.U.)6.5 - 8.5 NA 5.91 (5.78)NA NA NA NA 6.64 NA 6.1 NA
Nitrate + Nitrite (as N) (mg/L)5.6 NA 5.8 NA NA NA NA 5.9 NA 5.7 NA
Chloride (mg/L)38 NA 42 NA NA NA NA 42 NA 45 NA
Sulfate (mg/L)462 NA 469 NA NA NA NA 461 NA 452 NA
Field pH (S.U.)6.5-8.5 NA 6.78 NA NA NA NA 7.68 NA 6.89 NA
TDS (mg/L)1075 NA 1160 NA NA NA NA 1060 NA 1110 NA
Gross Alpha minus Rn & U (pCi/L)2 NA 1.6 NA NA NA NA NA NA 2.4 NA
Chloride (mg/L)105 NA 108 NA NA NA NA 106 NA 107 NA
Manganese (ug/L)1837 NA 1550 NA NA NA NA NA NA 1510 NA
Field pH (S.U.)6.1 - 8.5 NA 5.67 NA NA NA NA 5.91 NA 5.72 NA
Iron (ug/L)1869 NA 1630 NA NA NA NA NA 1490 NA
Manganese (ug/L)5624 NA 4820 NA NA NA NA NA 4890 NA
TDS (mg/L)4400 NA 4400 NA NA NA NA NA 4390 NA
Field pH (S.U.)6.46 - 8.5 NA 6.82 NA NA NA NA NA 6.17 NA
Gross Alpha minus Rn & U (pCi/L)3.33 NA 4.5 NA NA NA NA 2.9 NA 8.8 NA
Field pH (S.U.)6.4 - 8.5 NA 6.03 NA NA NA NA 6.33 NA 6.05 NA
Notes:
Values in () parentheses are the field pH measurements for the resampled analyses.
MW-19 (Class III)5/4/2010 9/15/2010 11/18/2010
11/19/2010MW-12 (Class III)4/27/2010NS
NS
MW-18 (Class III)5/4/2010 9/15/2010 11/18/2010
NS
NSMW-15 (Class III)4/21/2010
NS
MW-23 (Class III)4/22/2010 9/14/2010 11/22/2010NS
NS NS
NS
NSNS
NS
NS
NS
NS
NS
NS
NS
NS NS
5/3/2010 9/14/2010
NS
NS
Exceedances are shown in yellow
NS = Not Required and Not Sampled
NR = Required and Not Reported
NA = Not Applicable
MW-32 (Class III)4/20/2010 9/13/2010 11/10/2010
GWCL values are taken from August 24, 2012 version of GWDP.
NS NS NS NS
11/17/2010
11/12/2010
11/11/2010
NS
9/21/2010
NS
NS NS
9/20/2010NSNSNS
NS
NS
NS
NS
NS
NS
NS
NS
NS
NS
NS
NS
NS
NSNS
NS
NS
NS
NS
NS
NS
NS
NS
NS
MW-29 (Class III)4/27/2010
MW-28 (Class III)4/19/2010 NS
NS
MW-27 (Class III)NS
NS
NS
9/14/2010 NS
NS
NS
NS
NS
NS NSNS
MW-24 (Class III)5/6/2010
NS NA 11/9/2010
11/12/2010
NS
Required Semi-Annual Sampling Wells (continued)
APPENDIX A
GWCL Exceedances for Fourth Quarter 2013 Under the August 24, 2012 GWDP
Page 3 of 8
Appendix A
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
Monitoring Well
(Water Class)
Constituent Exceeding
GWCL
GWCL in
August 24, 2012 GWDP
January 2011
Monthly Sample Date
January 2011
Monthly Sample Result
Q1 2011
Sample Date
Q1 2011
Result
March 2011
Monthly Sample Date
March 2011
Monthly
Result
Q2 2011
Sample Date
Q2 2011
Result
May 2011
Monthly Sample Date
May 2011
Monthly Result
June 2011
Monthly Sample Date
June 2011
Monthly Result
July 2011
Monthly Sample Date
July 2011
Monthly Result
Q3 2011
Sample Date
Q3 2011
Result
September 2011
Monthly
Sample Date
September
2011 Monthly Result
Q4 2011
Sample Date
Q4 2011
Result
November
2011 Monthly Sample Date
November
2011 Monthly Result
December
2011 Monthly Sample Date
December 2011
Monthly
Result
Field pH (S.U.)6.5 - 8.5 7.43 7.47 7.94 7.50 7.25 6.86 7.07 7.25 7.29 7.52 7.47 7.88
Manganese (ug/L)131.29 121 145 68 148 170 121 151 118 106 112 105 100
Manganese (ug/L)2230.30 NA 2020 NA 2140 NA NA NA 1990 NA 1960 NA NA
Field pH (S.U.)6.5 - 8.5 6.37 6.22 6.76 6.63 6.37 5.83 6.4 6.23
(6.41)6.50 6.71 (6.82)6.63 6.84
Field pH (S.U.)6.5 - 8.5 6.44 6.66 6.79 6.7 6.1 5.77 6.29 8/3/2011
8/30/11
6.42
(6.54)6.54 6.6 6.51 6.87
Cadmium (ug/L)1.5 NA 1.34 NA 1.27 NA NA NA 8/30/2012 1.19 NA 1.27 NA NA
Chloride (mg/L)35 NA 30 NA 31 NA NA NA 32 NA 32 NA NA
Fluoride (mg/L)0.42 NA 0.31 NA 0.28 NA NA NA 0.31 NA 0.32 NA NA
Uranium 6.5 7.02 4.77 6.8 5.56 6.72 7.06 6.74 6.37 5.96 5.27 6.56 6.1
Nitrate + Nitrite (as N) (mg/L)0.62 0.2 0.25 0.6 0.8 0.4 0.3 0.9 0.6 2.4 0.9 1.3 2.3
Uranium (ug/L)41.8 32 69.3 31.8 60.2 57.4 18.5 57.1 19.0 56.1 58.9 55.6 57
Chloroform (ug/L)70 800 730 1200 390 1900 730 300 1000 1300 440 1200 1400
Chloride (mg/L)58.31 52 59 64 64 54 39 64 60 66 61 55 62
Field pH (S.U.)6.74 - 8.5 6.83 6.06 6.89 6.22 6.43 6.52 6.35 6.07 (6.58)6.71 6.82 6.75 7.1
Dichloromethane (Methylene
Chloride) (ug/L)5 <1.0 10 14 3.1 20 7 2.4 10 7.9 2.6 8.9 11
Nitrate + Nitrite (as N) (mg/L)2.5 15 16 17 16 16 17 17 14 16 16 16 16
Chloride (mg/L)128 NS 134 NS 134 128 127 127 126 145 129 122 124
Uranium (ug/L)8.32 NS 5.97 NS 6.49 NS NS NS 8 NS 9.83 NS NS
Selenium (ug/L)34 36.2 34.7 34 44.4 38.3 38.7 32.4 39.7 32.4 36.6 36.8 38
Nitrate + Nitrite (as N) (mg/L)5 19 21 22 21 20 22 22 20 21 21 21 21
TDS (mg/L)1320 1240 1220 1250 1370 1290 1330 1280 1300 1300 1320 1290 1330
Chloride (mg/L)143 NS 145 NS 143 143 145 148 148 148 145 145 148
Selenium (ug/L)71 NS 64.6 NS 65.2 NS NS NS 66.2 NS 68.8 NS NS
Field pH (S.U.)6.5 - 8.5 6.65 7.21 7.43 7.01 6.73 6.16!6.64 6.67 7.03 7.28 7.01 (7.34)7.46
Sulfate (mg/L)532 NS 538 531 503 512 540 532 537 541 539 552 530
Manganese (ug/L)200 NA 248 NA 369 NA NA 348 267 270 271 283 247
Thallium (ug/l)0.5 NA < 0.50 NA < 0.50 NA NA NA 0.52 NA 0.57 < 0.50 0.63
Molybdenum (ug/L)10 NA <10 NA <10 NA NA NA <10 NA <10 NA NA
Gross Alpha minus Rn & U (pCi/L)3.75 NA 2.6 NA 3.7 NA NA NA 4.5 NA 4.4 4.7 4.2
Selenium (ug/L)12.5 NA ND NA ND NA NA NA 9.3 NA 10.5 NA NA
Uranium (ug/L)7.5 NA 12.7 NA 21.7 NA NA 24.2 18.3 22.3 20.1 24 23.6
Manganese (ug/L)289 NA NA NA 4/11/2011 218 NA NA NA NA NA 206 NA NA
Tetrahydrofuran (ug/L)11.5 NA NA NA 4/19/2011 10.7 NA NA NA NA NA 7.82 NA NA
Sulfate (mg/L)838 NA NA NA 4/11/2011 704 NA NA NA NA NA 713 NA NA
Selenium (ug/L)37 NA 40.5 NA 45.4 NA NA NA 46 NA 46.7 NA NA
Field pH (S.U.)6.5 - 8.5 NA 6.09 NA 6.46 NA NA NA 6.32 NA 6.53 (6.83)NA NA
Sulfate (mg/L)3663 NA NA NA 3060 NA NA NA NA NA 3470 NA NA
Nitrate + Nitrite (as N) (mg/L)0.73 NA NA NA 0.3 NA NA NA NA NA 0.3 NA NA
Fluoride (Mg/L)0.68 NA 0.69 NA 0.68 NA NA NA 0.96 NA 0.91 NA NA
Field pH (S.U.)6.5 - 8.5 NA 6.05 NA 6.58 NA NA NA 6.19 NA 6.5 (6.92)NA NA
Sulfate (mg/L)3640 NA 3730 NA 3350 NA NA NA 3560 NA 3750 NA NA
Nitrate + Nitrite (as N) (mg/L)1.3 NA NA NA 1.2 NA NA NA NA NA 1.1 NA NA
TDS (mg/L)5805 NA 5770 NA 5720 NA NA NA 5810 NA 5630 NA NA
Selenium (ug/L)89 NA 99 NA 85.8 NA NA NA 88.5 NA 95 NA NA
MW-05 (Class II)Uranium (ug/L)7.5 NS NA 2/14/2011 29.5 NS NA 4/12/2011 7.16 NS NA NS NA NS NA 8/9/2011 0.5 NS NA 10/10/2011 4.52 NS NA NS NA
7/6/2011 8/3/2011
8/30/11 9/7/2011 10/4/2011 11/9/2011 12/14/2011
Q4 2011 Results
Required Quarterly Sampling Wells
Q1 2011 Results Q2 2011 Results Q3 2011 Results
9/7/2011
MW-11 (Class II)1/11/2011 2/2/2011 3/15/2011 4/4/2011 5/10/2011 6/15/2011
12/12/201111/9/20117/5/2011 8/3/2011 9/8/2011
3/15/2011 4/4/2011 5/11/2011
5/10/2011 6/15/2011
8/3/2011
MW-14 (Class III)1/11/2011 2/7/2011 3/14/2011 4/4/2011
6/20/2011 7/6/2011MW-25 (Class III) 1/11/2011
MW-01 (Class II)
NS
NS
NS
10/11/2011
3/14/2011
MW-30 (Class II)
NS NS2/16/2011
8/10/2011 10/10/2011
MW-31 (Class III) 1/10/2011 2/1/2011
6/20/2011 7/5/2011 8/3/2011 9/7/2011 10/4/2011 11/8/20111/10/2011 2/1/2011
NSMW-35 (Class II)
NS
NS NS
2/15/2011 6/7/2011
NS NSNSNS
NS NSNS2/15/2011 4/13/2011
7/20/11
2/2/2011
Required Semi-Annual Sampling Wells
NS
NS
NS
NS
NS
MW-03 (Class III)
9/7/11
NS4/13/2011 8/11/2011 10/11/2011
4/1/2011 5/10/2011 6/20/2011 7/5/2011 8/2/2011 9/6/2011 10/3/2011 11/8/2011
(11/29/12)
NS
NS
NSNS
NS
6/20/2011 7/6/2011 9/7/2011 10/12/2011 11/9/2011
12/12/2011
8/30/2011
MW-03A (Class III)
8/3/2011
8/30/11
10/3/11 11/8/2011 12/14/11
12/12/2011
NS
12/14/2011MW-26 (Class III)1/12/2011 2/16/2011 3/15/2011 4/1/2011 5/10/2011
3/14/2011 4/11/2011 5/10/2011
10/4/2011 11/9/2011 12/12/2011
10/4/2011
NS NS
APPENDIX A
GWCL Exceedances for Fourth Quarter 2013 Under the August 24, 2012 GWDP
Page 4 of 8
Appendix A
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
Monitoring Well
(Water Class)
Constituent Exceeding
GWCL
GWCL in
August 24, 2012 GWDP
January 2011
Monthly Sample Date
January 2011
Monthly Sample Result
Q1 2011
Sample Date
Q1 2011
Result
March 2011
Monthly Sample Date
March 2011
Monthly
Result
Q2 2011
Sample Date
Q2 2011
Result
May 2011
Monthly Sample Date
May 2011
Monthly Result
June 2011
Monthly Sample Date
June 2011
Monthly Result
July 2011
Monthly Sample Date
July 2011
Monthly Result
Q3 2011
Sample Date
Q3 2011
Result
September 2011
Monthly
Sample Date
September
2011 Monthly Result
Q4 2011
Sample Date
Q4 2011
Result
November
2011 Monthly Sample Date
November
2011 Monthly Result
December
2011 Monthly Sample Date
December 2011
Monthly
Result
Q4 2011 Results

Q1 2011 Results Q2 2011 Results Q3 2011 Results
Field pH (S.U.)6.5 - 8.5 NA 6.43 NA 6.67 NA NA NA 6.13 NA 6.7 (6.97)NA NA
Selenium (ug/L)25 NA 39 NA 21.7 NA NA NA 25.4 NA 35.4 NA NA
Selenium (ug/L)128.7 NA NA NA 116 NA NA NA NA NA 112 NA NA
Field pH (S.U.)6.62 - 8.5 NA NA NA 6.88 NA NA NA NA NA 6.70 NA NA
Iron (ug/L)81.7 NA NA NA <0.50 NA NA NA NA NA 137 NA NA
Thallium (ug/l)1.95 NA 3.49 NA 3.74 NA NA NA 4.0 3.39 NA 3.83 NA NA
Sulfate (mg/L)1938.9 NA 1770 NA 1780 NA NA NA 1910 NA 2020 NA NA
Field pH (S.U.)6.25-8.5 NA 6.27 NA 6.71 NA NA NA 5.95
6 NA 6.55 (6.63)NA NA
TDS (mg/L)3198.77 NA 3250 NA 3250 NA NA NA 3190 NA 3220 NA NA
Field pH (S.U.)6.78-8.5 NA 6.78 NA 7.03 NA NA NA 6.65 NA 6.88 (7.02)NA NA
Gross Alpha minus Rn & U
(pCi/L)2.36 NA NA NA 0.5 NA NA NA NA NA 0.6 NA NA
Nitrate + Nitrite (as N) (mg/L)2.83 NA NS NA 2.6 NA NA NA NS NA 4.0 NA NA
Field pH (S.U.)6.5 - 8.5 NA 6.13 NA 7.14 NA NA NA 6.38 NA 6.56 (6.77)NA NA
Manganese (ug/L)550 NA NS NA 32 NA NA NA NS NA 551 NA NA
Cadmium (ug/L)2.5 NA 2.78 NA 2.61 NA NA NA 1.46 NA 1.78 NA NA
Fluoride (Mg/L)0.36 NA NA NA 0.19 NA NA NA NA NA 0.36 NA NA
Thallium (ug/L)1 NA 1.42 NA 1.07 NA NA NA <0.50 NA 0.62 NA NA
Field pH (S.U.)6.5 - 8.5 NA 5.73 NA 6.12 NA NA NA 6.45 NA 6.44 NA NA
Nitrate + Nitrite (as N) (mg/L)5.6 NA 6 NA 6.4 NA NA NA 6 NA 6.3 NA NA
Chloride (mg/L)38 NA 46 NA 43 NA NA NA 43 NA 44 NA NA
Sulfate (mg/L)462 NA 455 NA 442 NA NA NA 424 NA 456 NA NA
Field pH (S.U.)6.5-8.5 NA 6.71 NA 6.79 NA NA NA 6.39 NA 7.17 (7.24)NA NA
TDS (mg/L)1075 NA 1090 NA 1190 NA NA NA 1090 NA 1110 NA NA
Gross Alpha minus Rn & U (pCi/L)2 NA 0.7 NA 1.1 NA NA NA 0.8 NA 1.5 NA NA
Chloride (mg/L)105 NA 114 NA 109 NA NA NA 105 NA 143 NA NA
Manganese (ug/L)1837 NA NA NA 1690 NA NA NA NA NA 1540 NA NA
Field pH (S.U.)6.1 - 8.5 NA 5.69 NA 6.01 NA NA NA 5.78 NA 6.07(6.11)NA NA
Iron (ug/L)1869 NA NS NA NA 3010 NA NA NA 1080 NA 1220 NA NA
Manganese (ug/L)5624 NA NS NA NA 4900 NA NA NA NA NA 4800 NA NA
TDS (mg/L)4400 NA NS NA NA 4080 NA NA NA NA NA 4280 NA NA
Field pH (S.U.)6.46 - 8.5 NA NS NA NA 6.45 NA NA NA 6.20 NA 6.52 NA NA
Gross Alpha minus Rn & U (pCi/L)3.33 NA 1.5 NA 4.6 NA NA NA 1.9 NA 3.7 NA NA
Field pH (S.U.)6.4 - 8.5 NA 5.99 NA 6.14 NA NA NA 6.10 (6.20)NA 6.35 NA NA
Notes:
Values in () parentheses are the field pH measurements for the resampled analyses.
MW-19 (Class III)
MW-15 (Class III)
MW-12 (Class III)
MW-18 (Class III)
MW-23 (Class III)
NS
NS
2/9/2011NS
NS
Exceedances are shown in yellow
NS = Not Required and Not Sampled
NR = Required and Not Reported
NA = Not Applicable
GWCL values are taken from August 24, 2012 version of GWDP.
MW-32 (Class III)2/9/2011NS NSNSNS
MW-24 (Class III)
2/9/2011 4/5/2011 10/5/2011
NS
MW-27 (Class III)
4/5/2011
NS
NS
NS
NS
NS
NS
8/9/2011 10/6/2011 NS
NSNS
NSNSNSNS4/1/2011 8/2/2011
8/30/11 10/3/2011
NS
NS
NS
NS
NS
NSNS2/15/2011
NS
2/10/2011NS
2/21/2011
2/15/2011
MW-29 (Class III)
MW-28 (Class III)
NS
2/14/2011NS
NS
10/5/2011
4/11/2011 8/8/2011 10/5/2011NS
NS
NS
NS 8/10/2011
9/21/11 10/11/2011
NS
NS
NS
NS
8/8/2011
NS
NS7/20/3011 10/12/2011NS
NS
NS
8/4/2011 10/6/2011
NS
NS
NS 8/4/2011 10/11/2011
4/5/2011
NS NSNS
NS
NS
NS
NS
NS
NS
NS
NS
NS
NS
NS
4/12/2011
4/18/2011 8/9/2011
NS
NS
4/5/2011
4/5/2011
4/6/2011
NS
NS
NS
NS
NS
NSNS
NS
NSNS
NS
NS
NS
NS
NS
NS
10/10/2011
Required Semi-Annual Sampling Wells (continued)
APPENDIX A
GWCL Exceedances for Fourth Quarter 2013 Under the August 24, 2012 GWDP
Page 5 of 8
Appendix A
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
Monitoring Well
(Water Class)
Constituent
Exceeding GWCL
GWCL in
August 24, 2012 GWDP
January 2012
Monthly Sample Date
January 2012
Monthly Result
Q1 2012
Sample Date
Q1 2012
Result
March 2012
Monthly Sample Date
March 2012
Monthly Result
April 2012
Monthly Sample Date
April 2012
Monthly Result
Q2 2012
Sample Date
Q2 2012
Result
June 2012 Monthly
Sample
Date
June 2012
Monthly Result
Q3 2012
Sample Date
Q3 2012
Result
August 2012
Monthly Sample Date
August 2012
Monthly
Result
September
2012
Monthly Sample
Date
September 2012
Monthly
Result
October
2012
Monthly Sample
Date
October 2012
Monthly
Result
Q4 2012
Sample Date
Q4 2012
Result
December
2012
Monthly Sample
Date
December 2012
Monthly
Result
Field pH (S.U.)6.5 - 8.5 7.51 7.59 7.47 7.66 7.49 7.82 7.74 7.43 7.91 7.39 7.47 7.46
Manganese (ug/L)131.29 102 154 121 132 127 122 135 166 130 161 138 137
Manganese (ug/L)2230.30 NA 1790 NA NA 2360 NA 2100 2300 2140 2110 2100 1950
Field pH (S.U.)6.5 - 8.5 6.36 6.57 6.51 6.97 6.73 6.90 6.89 6.58 7.08 6.83 6.52 6.60
Field pH (S.U.)6.5 - 8.5 6.63 6.83 6.55 6.58 6.73 6.99 6.88 6.55 6.54 6.54 6.47 6.62
Cadmium (ug/L)1.5 NA 1.31 NA NA 1.33 NA 1.24 NA NA NA 1.56 NA
Chloride (mg/L)35 NA 30 NA NA 30 NA 33 NA NA NA 28.8 NA
Fluoride (mg/L)0.42 NA 0.34 NA NA 0.32 NA 0.3 NA NA NA 0.298 NA
Uranium 6.5 6.6 6.5 6.93 6.52 5.90 7.6 6.45 6.72 6.01 6.37 6.61 4.83
Nitrate + Nitrite (as
N) (mg/L)0.62 1.9 2/15/2012 1.2 3 3.4 2.9 2.3 1.9 1.6 1.8 3.5 0.55 1.46
Uranium (ug/L)41.8 64.6 2/21/2012 59.4 31.2 42.2 18.2 66.0 28.4 67.4 64.9 26.9 56.8 51.3
Chloroform (ug/L)70 1900 3300 2900 2900 1700 2400 8/16/2012 970 2200 2300 4720 4020 1250
Chloride (mg/L)58.31 68 40 74 82 74 85 7/11/2012 78 78 67 2.62 52.9 65.9
Field pH (S.U.)6.74 - 8.5 6.59
2/15/2012
2/21/2012
3/8/2012
6.72 (6.91) (6.71)6.39 6.88 7.00 (7.01)7.00 7/11/2012 8/16/2012 7.10 (6.80)6.60 7.40 6.63 6.60 6.78
Dichloromethane
(Methylene Chloride)
(ug/L)
5 13 2/15/2012 24 27 20 10 16 8/16/2012 4.9 17 9.8 15.0 34.6 5.5
Nitrate + Nitrite (as
N) (mg/L)2.5 17 17 18 17 16 15 17 18 16 16.2 18.5 17.2
Chloride (mg/L)128 124 126 128 128 124 131 128 139 130 135 114 122
Uranium (ug/L)8.32 NS NA 7.42 8.38 7.84 6.81 7.8 7.64 8.04 7.67 7.86 7.03 5.80
Selenium (ug/L)34 1/24/2012 33.3 35 39.5 39.1 32.3 37 38.5 38.4 41.9 45.2 36 31.6
Nitrate + Nitrite (as N) (mg/L)5 21 21 22 21 20 21.6 21 21 21 18 23.6 22.2
TDS (mg/L)1320 1360 1240 1400 1380 1410 1460 1400 1400 1460 1320 1230 1270
Chloride (mg/L)143 155 150 152 160 151 138 161 175 172 157 189 170
Selenium (ug/L)71 NS 67.8 NS NS 70.2 NA 74 NA NA NA 76.9 NA
Field pH (S.U.)6.5 - 8.5 6.78 7.37 7.13 7.14 7.19 7.28 (7.63)7.53 6.96 7.1 7.05 7.04 7.10
Sulfate (mg/L)532 539 538 517 547 532 497 529 571 561 545 557 664
Manganese (ug/L)200 264 253 269 277 258 304 272 273 283 253 241 240
Thallium (ug/l)0.5 < 0.50 0.65 0.71 0.59 0.66 < 0.50 0.57 0.61 0.54 0.517 0.554 0.5
Molybdenum (ug/L)10 <10 <10 NA NA <10 NA <10 NA NA NA 30.4 NA
Gross Alpha minus Rn & U (pCi/L)3.75 6.5 4.1 6.2 4.1 4.5 4.9 3.5 4.2 5.4 4.31 4.23 6.5
Selenium (ug/L)12.5 NA 19.7 NA NA 11.4 7.0 15.9 18.8 8.2 19.0 15.4 12.1
Uranium (ug/L)7.5 16.1 24.7 24.9 22.4 22.2 22.5 24.5 26.2 22.9 22.4 21.8 21
Manganese (ug/L)289 NA NA NA NA 176 NA NA NA NA NA 315 NA
Tetrahydrofuran (ug/L)11.5 NA NA NA NA 10.3 NA NA NA NA NA 21.8 NA
Sulfate (mg/L)838 NA NA NA NA 659 NA NA NA NA NA 846 NA
Selenium (ug/L)37 NA 43.1 NA NA 52.8 NA 51.1 NA NA NA 58.9 NA
Field pH (S.U.)6.5 - 8.5 NA 6.63 NA NA 6.67 NA 6.99 NA NA NA 6.55 NA
Sulfate (mg/L)3663 NA NA NA NA 3140 NA NA NA NA NA 2340 NA
Nitrate + Nitrite (as
N) (mg/L)0.73 NA NA NA NA 0.4 NA NA NA NA NA 0.419 NA
Fluoride (Mg/L)0.68 NA 0.86 NA NA 1.04 NA 0.96 NA NA NA 1.26 NA
Field pH (S.U.)6.5 - 8.5 NA 6.46 NA NA 6.68 NA 7.01 NA NA NA 6.35 NA
Sulfate (mg/L)3640 NA 3020 NA NA 3220 NA 3700 NA NA NA 2780 NA
Nitrate + Nitrite (as
N) (mg/L)1.3 NA NA NA NA 1.1 NA NA NA NA NA 1.31 NA
TDS (mg/L)5805 NA 5690 NA NA 5730 NA 5720 NA NA NA 5610 NA
Selenium (ug/L)89 NA 65.8 NA NA 85.1 NA 99.3 NA NA NA 111 NA
MW-05 (Class II)Uranium (ug/L)7.5 NS NA 2/28/2012 18.6 NS NA NS NA 5/9/2012 1.23 NS NA 7/16/2012 0.75 NS NA NS NA NS NA 11/27/2012 0.402 NS NA
3/13/2012 4/10/2012 5/8/2012 6/19/2012 7/11/2012 8/7/2012 9/19/2012 10/23/2012 11/12/2012MW-11 (Class II)1/26/2012 2/13/2012
Q3 2012 Results
7/11/2012
7/10/2012
7/11/2012
6/19/2012
6/18/2012
6/19/2012 8/8/2012
3/14/20121/25/2012
8/8/20127/10/2012
Q1 2012 Results
MW-14 (Class III)
NS
MW-03 (Class III)2/29/2012
9/19/2012
7/18/2012
6/19/2012
NS NS
NS
4/10/2012
5/14/2012
5/2/2012
5/1/2012 NS
NS
NS
NS
Required Semi-Annual Sampling Wells
NS
MW-01 (Class II)NS
NS
4/11/2012
2/15/2012
NS
NS
NS
2/14/2012MW-35 (Class II)3/13/2012
Q4 2012 Results
Required Quarterly Sampling Wells
5/2/2012 6/18/2012
6/29/2012 7/9/2012 8/6/20123/13/2012 4/9/2012
12/18/2012
12/24/2012
12/26/2012
12/18/2012
4/9/2012 5/2/2012
5/7/2012
6/26/2012
4/12/2012
5/2/2012
Q2 2012 Results
12/24/2012
MW-31 (Class III) 1/24/2012 2/13/2012
1/24/2012 2/21/2012
MW-30 (Class II)
1/24/2012
2/14/2012 3/14/2012 4/10/2012
MW-25 (Class III) 2/14/2012
3/14/2012
NSNSMW-03A (Class III)NS
NS
NS
NSNS5/15/2012NS
MW-26 (Class III)1/25/2012 3/14/2012
1/24/2012
3/1/2012 NS7/19/2012
10/24/2012 11/15/2012 12/24/2012
10/23/2012
11/27/2012
11/12/2012
9/19/2012
11/13/2012
11/6/2012
11/13/2012
9/18/2012
9/18/2012
9/18/2012
5/9/2012 10/23/2012
10/22/2012
6/18/2012 7/10/2012 8/7/2012 9/19/2012
8/7/2012
10/22/2012
10/23/2012
NS
NS
NS
12/18/2012
11/27/2012
11/28/2012
11/29/2012
8/6/2012
APPENDIX A
GWCL Exceedances for Fourth Quarter 2013 Under the August 24, 2012 GWDP
Page 6 of 8
Appendix A
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
Monitoring Well
(Water Class)
Constituent
Exceeding GWCL
GWCL in
August 24, 2012 GWDP
January 2012
Monthly Sample Date
January 2012
Monthly Result
Q1 2012
Sample Date
Q1 2012
Result
March 2012
Monthly Sample Date
March 2012
Monthly Result
April 2012
Monthly Sample Date
April 2012
Monthly Result
Q2 2012
Sample Date
Q2 2012
Result
June 2012 Monthly
Sample
Date
June 2012
Monthly Result
Q3 2012
Sample Date
Q3 2012
Result
August 2012
Monthly Sample Date
August 2012
Monthly
Result
September
2012
Monthly Sample
Date
September 2012
Monthly
Result
October
2012
Monthly Sample
Date
October 2012
Monthly
Result
Q4 2012
Sample Date
Q4 2012
Result
December
2012
Monthly Sample
Date
December 2012
Monthly
Result
Q3 2012 ResultsQ1 2012 Results Q4 2012 Results

Q2 2012 Results
Field pH (S.U.)6.5 - 8.5 NA 6.81 NA NA 6.91 NA 6.98 NA NA NA 6.54 NA
Selenium (ug/L)25 NA 27.2 NA NA 19.6 NA 20.7 NA NA NA 23 NA
Selenium (ug/L)128.7 NA NA NA NA 152 NA 120 NA NA NA 117 NA
Field pH (S.U.)6.62 - 8.5 NA 6.84 NA NA 6.63 NA 7.05 NA NA NA 6.86 NA
Iron (ug/L)81.7 NA < 30 NA NA < 30 NA < 30 NA NA NA <30 NA
Thallium (ug/l)1.95 NA 3.63 NA NA 3.51 NA 3.73 NA NA NA 3.2 NA
Sulfate (mg/L)1938.9 NA 1920 NA NA 1790 NA 1900 NA NA NA 1210 NA
Field pH (S.U.)6.25-8.5 NA 6.6 NA NA 6.59 NA 6.64 NA NA NA 6.51 NA
TDS (mg/L)3198.77 NA 3230 NA NA 3280 NA 3220 NA NA NA 3160 NA
Field pH (S.U.)6.78-8.5 NA 6.83 NA NA 6.86 NA 7.21 NA NA NA 6.71 NA
Gross Alpha minus
Rn & U (pCi/L)2.36 NA NA NA NA 0.9 NA NA NA NA NA 4.86 NA
Nitrate + Nitrite (as
N) (mg/L)2.83 NA 3.9 NA NA 3.7 NA 4 NA NA NA 3.96 NA
Field pH (S.U.)6.5 - 8.5 NA 6.61 NA NA 6.74 NA 7.10 NA NA NA 6.61 NA
Manganese (ug/L)550 NA 51 NA NA 49 NA 117 NA NA NA 54.3 NA
Cadmium (ug/L)2.5 NA 2.25 NA NA 2.01 NA 4.7 NA NA NA 1.35 NA
Fluoride (Mg/L)0.36 NA NA NA NA 0.14 NA NA NA NA NA 0.558 NA
Thallium (ug/L)1 NA 0.96 NA NA 0.74 NA 1.36 NA NA NA 0.666 NA
Field pH (S.U.)6.5 - 8.5 NA 6.03 NA NA 6.21 NA 6.45 NA NA NA 6.01 NA
Nitrate + Nitrite (as
N) (mg/L)5.6 NA 6.4 NA NA 6.2 NA 6.7 NA NA NA 6.9 NA
Chloride (mg/L)38 NA 45 NA NA 46 NA 47 NA NA NA 44.2 NA
Sulfate (mg/L)462 NA 451 NA NA 446 NA 453 NA NA NA 451 NA
Field pH (S.U.)6.5-8.5 NA 7.24 NA NA 7.03 NA 7.40 NA NA NA 6.69 NA
TDS (mg/L)1075 NA 1140 NA NA 1170 NA 1150 NA NA NA 1070 NA
Gross Alpha minus Rn & U (pCi/L)2 NA 2.3 NA NA 0.8 NA 1.2 NA NA NA 1.33 NA
Chloride (mg/L)105 NA 109 NA NA 114 NA 7/16/2012 105 NA NA NA 115 NA
Manganese (ug/L)1837 NA NA NA NA 1850 NA 8/1/2012 1660 NA NA NA 1680 NA
Field pH (S.U.)6.1 - 8.5 NA 6.22 NA NA 6.15 NA 7/16/2012 8/1/2012 6.38 (5.81)NA NA NA 5.98 NA
Iron (ug/L)1869 NA 1310 NA NA 1400 NA 7/16/2012 1270 NA NA NA 1350 NA
Manganese (ug/L)5624 NA NA NA NA 6140 NA 8/1/2012 5190 NA NA NA 5040 NA
TDS (mg/L)4400 NA NA NA NA 4600 NA 8/1/2012 4420 NA NA NA 4430 NA
Field pH (S.U.)6.46 - 8.5 NA 7.12 NA NA 6.47 NA 7/16/2012
8/1/2012 6.68 (6.45)NA NA NA 6.48 NA
Gross Alpha minus Rn & U (pCi/L)3.33 NA 1.8 NA NA 2.4 NA 1.4 NA NA NA 2.97 NA
Field pH (S.U.)6.4 - 8.5 NA 6.57 NA NA 6.40 NA 6.72 NA NA NA 6.23 NA
Notes:
Values in () parentheses are the field pH measurements for the resampled analyses.
7/9/2012NS
MW-29 (Class III)
NS
NS
NS
4/30/2012
NS
NS
NS
NS
NS
NS
NS
NS
NS
7/18/2012
7/19/2012
7/17/2012
7/18/20125/10/2012
5/1/2012
5/8/2012
5/8/2012 NS
7/16/2012
NS
Exceedances are shown in yellow
NS = Not Required and Not Sampled
NR = Required and Not Reported
NA = Not Applicable
GWCL values are taken from August 24, 2012 version of GWDP.
NSMW-32 (Class III)2/21/2012
2/22/2012
2/28/2012
NS
NS
NS
NSMW-23 (Class III)
MW-19 (Class III)
MW-18 (Class III)
NS
MW-27 (Class III)2/28/2012
NS
NS
NS
NS
NS
NS
NS
NS
NS
NS
NS
4/30/2012
5/16/2012
5/16/2012
NS
NS
MW-15 (Class III)
MW-12 (Class III)
12/5/2012
11/29/2012
11/13/2012
11/14/2012
11/14/2012
11/6/2012
11/14/2012
NSNS
NS
NS
5/10/2012
NS
NS
NS
NS
NS
NS
NS
5/9/2012
NS
NS
NS
2/27/2012 NS
NS
NS2/20/2012
MW-24 (Class III)2/23/2012
2/22/2012
NS
NS
NS
NS
NS
NS
NS
NS
NS
NS
NS
NS
7/17/2012
7/17/2012
MW-28 (Class III)2/28/2012
NS
NS
NS
NS
NS
NS
NS
NS
NS
NS
NS
NS
NS
NS
NS
NS
11/27/2012
11/26/2012
12/13/2012
2/29/2012 NS
Required Semi-Annual Sampling Wells (continued)
APPENDIX A
GWCL Exceedances for Fourth Quarter 2013 Under the August 24, 2012 GWDP
Page 7 of 8
Appendix A
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
Monitoring Well
(Water Class)
Constituent
Exceeding GWCL
GWCL in August 24,
2012 GWDP
January 2013
Monthly Sample Date
January 2013
Monthly
Result
Q1 2013
Sample Date
Q1 2013
Result
March 2013 Monthly
Sample
Date
March 2013
Monthly Result
April 2013
Monthly Sample Date
April 2013
Monthly Result
Q2 2013
Sample Date
Q2 2013
Result
June 2013 Monthly
Sample
Date
June 2013
Monthly Result
Q3 2013
Sample Date
Q3 2013
Result
August
2013
Monthly Sample
Date
August 2013
Monthly
Result
September
2013
Monthly Sample
Date
September 2013
Monthly
Result
October 2013
Monthly
Sample Date
October 2013
Monthly
Result
Q4 2013
Sample Date
Q4 2013
Result
December
2013
Monthly Sample
Date
December 2013
Monthly
Result
Sample
Frequency
Field pH (S.U.)6.5 - 8.5 7.45 7.46 7.33 6.17 7.88 7.47 7.40 7.70 7.39 7.62 7.33 7.74 Quarterly
Manganese (ug/L)131.29 115 139 164 181 144 135 138 158 134 129 152 196 Quarterly
Manganese (ug/L)2230.30 1930 2250 2110 2060 2200 1990 2100 2100 2190 2030 1960 2030 Quarterly
Field pH (S.U.)6.5 - 8.5 6.48 6.52 6.48 7.58 7.39 6.54 6.47 6.86 6.48 6.77 6.51 6.74 Quarterly
Field pH (S.U.)6.5 - 8.5 6.65 6.62 6.41 7.00 7.19 6.61 6.32 6.74 6.54 6.81 6.62 6.73 Quarterly
Cadmium (ug/L)1.5 NA 1.35 1.40 1.36 1.52 1.31 1.41 1.57 1.31 1.50 1.35 1.23 Quarterly
Chloride (mg/L)35 NA 36.1 NA NA 28.1 30.4 28.0 31.1 29.6 28.6 29.0 31.2 Quarterly
Fluoride (mg/L)0.42 NA 0.32 NA NA 0.392 NA 0.534 NA NA NA 0.329 0.296 Quarterly
Uranium 6.5 5.97 5.39 5.68 5.56 5.88 5.35 6.22 6.42 5.99 5.94 7.13 NA Quarterly
Nitrate + Nitrite (as
N) (mg/L)0.62 1.66 1.38 1.61 1.73 2.01 3.04 2.11*1.98 1.77 3.60 4.10 1.38 2.56 Quarterly
Uranium (ug/L)41.8 65.7 57.8 69 58.8 64.3 71.3 70 72.3 19.9 58.8 75.8 70.4 Quarterly
Chloroform (ug/L)70 1270 1500 1340 1680 1210 4030*2410 2110 4170 3420 1220 1680 Quarterly
Chloride (mg/L)58.31 63.5 77 73.6 70.4 63.1 87.8 77.9*72.1 70.8 77.3 63.8 62.3 65.7 Quarterly
Field pH (S.U.)6.74 - 8.5 6.51 6.71 6.70 6.96 7.31 6.85 6.43 7.41 6.71 6.82 6.83 6.93 Quarterly
Dichloromethane
(Methylene
Chloride) (ug/L)
5 6.49 5.53 8.31 10.2 4.07 52.4*
[12.1]14.2 14.6 42.4 29.8 7.64 7.48 Quarterly
Nitrate + Nitrite (as
N) (mg/L)2.5 19.2 21.4 14.3 16.8 18.8 16.1 17.6 16.4 16.9 19.7 19.5 20.7 Quarterly
Chloride (mg/L)128 128 129 126 117 119 127 130 126 131 128 124 134 Quarterly
Uranium (ug/L)8.32 8.36 7.4 6.85 7.08 6.31 8.22 7.48 7.07 7.00 6.91 8.57 NA Quarterly
Selenium (ug/L)34 37.2 42.3 39 37.3 39.4 32.1 36.5 36.3 35.2 39.5 36.6 35.1 Quarterly
Nitrate + Nitrite (as N) (mg/L)5 22.8 19.3 19.1 18.8 23.8 20.0 21.7 16.0 21.2 21.2 23.9 24.2 Quarterly
TDS (mg/L)1320 1270 1390 1420 1260 1540 1380 1510 1440 1500 1460 1320 1500 Quarterly
Chloride (mg/L)143 176 174 168 171 169 179 182 183 193 188 174 203 Quarterly
Selenium (ug/L)71 NS 74.1 81.8 72.9 75.9 73.7 75.7 73.2 72.6 80.7 74.5 79.8 Quarterly
Field pH (S.U.)6.5 - 8.5 6.94 7.32 7.28 6.37 7.92 7.10 6.98 7.36 7.06 7.35 6.99 7.23 Quarterly
Sulfate (mg/L)532 611 644 611 668 630 659 659 656 666 637 609 656 Quarterly
Manganese (ug/L)200 247 272 246 243 252 243 250 262 257 240 251 260 Quarterly
Thallium (ug/l)0.5 <0.5 <0.5 0.505 <0.5 0.715 0.946 <0.5 <0.5 <0.5 <0.5 <0.5 <0.5 Quarterly
Molybdenum (ug/L)10 NS <10 <10 <10 <10 <10 <10 <10 <10 <10 <10 NA Quarterly
Gross Alpha minus Rn & U (pCi/L)3.75 6.62 5.09 9.51 4.75 4.92 3.24 5.70 3.92 5.10 3.73 5.39 4.74 Quarterly
Selenium (ug/L)12.5 11.0 10.8 22.6 11.8 16.1 13.6 8.01 <5 <5 19.8 <5 <5 Quarterly
Uranium (ug/L)7.5 23.6 21.3 22.1 20.0 22.0 19.3 23.0 21.4 20.2 21.8 24.1 20 Quarterly
Manganese (ug/L)289 NA 173 NA NA 127 NA 83.9 NA NA NA 113 NA Semi-Annually
Tetrahydrofuran (ug/L 11.5 NA 12.6 NA NA 3.26 NA 1.86 NA NA NA 5.51 NA Semi-Annually
Sulfate (mg/L)838 NA 761 NA NA 839 NA 911 NA NA NA 930 NA Semi-Annually
Selenium (ug/L)37 NA 51.8 NA NA 46.3 NA 52.0 NA NA NA 32.8 NA Semi-Annually
Field pH (S.U.)6.5 - 8.5 NA 6.20 NA NA 7.14 NA 6.46 NA NA NA 6.78 NA Semi-Annually
Sulfate (mg/L)3663 NA NA NA NA 2180 NA NA NA NA NA 3760 NA Semi-Annually
Nitrate + Nitrite (as
N) (mg/L)0.73 NA NA NA NA 0.456 NA NA NA NA NA 1.21 NA Semi-Annually
Fluoride (Mg/L)0.68 NA 0.902 NA NA 0.994 NA 1.18 NA NA NA 1.28 NA Semi-Annually
Field pH (S.U.)6.5 - 8.5 NA 6.84 NA NA 7.10 NA 6.50 NA NA NA 6.98 NA Semi-Annually
Sulfate (mg/L)3640 NA 3480 NA NA 3120 NA 3670 NA NA NA 3360 NA Semi-Annually
Nitrate + Nitrite (as
N) (mg/L)1.3 NA 1.22 NA NA 1.11 NA 1.09 NA NA NA 1.52 NA Semi-Annually
TDS (mg/L)5805 NA 5750 NA NA 6020 NA 5860 NA NA NA 5940 NA Semi-Annually
Selenium (ug/L)89 NA 88.7 NA NA 75.6 NA 79.7 NA NA NA 77.9 NA Semi-Annually
MW-05 (Class II)Uranium (ug/L)7.5 NS NA 3/11/2013 36 NS NA NS NA 5/14/2013 1.33 NS NA 7/18/2013 0.574 NS NA NS NA NS NA 12/4/2013 20.1 NS NA Semi-Annually
10/23/2013 11/18/2013 12/17/2013
10/23/2013 11/19/2013 12/17/2013
NS 12/4/2013 NS
Required Semi-Annual Sampling Wells
NS 12/11/2013 NS
MW-35 (Class II)1/23/2013 2/26/2013 3/19/13
MW-31 (Class III) 1/22/2013 2/19/2013 3/19/2013
5/13/2013 6/24/2013
4/17/2013 5/15/2013 6/25/2013
4/16/2013 5/13/2013 6/24/2013
7/11/2013 8/20/2013 9/18/2013
7/10/2013 8/20/2013 9/18/2013
7/9/2013 8/19/2013 9/17/2013
12/17/2013
10/23/2013 11/20/2013 12/18/2013
4/16/2013 5/14/2013 6/25/2013
MW-26 (Class III)1/24/2013 3/20/20132/20/2013
MW-25 (Class III) 1/22/2013 2/20/2013 3/19/2013 4/17/2013 5/14/2013 6/24/2013
4/17/2013 5/23/2013
MW-11 (Class II)1/23/2013
6/5/2013
6/25/2013
12/18/2013
Q3 2013 Results
10/22/2013 11/19/2013
7/9/2013 8/19/2013 9/17/2013
7/23/2013 NS NS
7/18/2013 NS NS
10/22/2013
7/19/2013 NS NS
11/20/2013 12/18/2013
7/10/2013 8/19/2013 9/17/2013
NS 12/11/2013 NSMW-03A (Class III)NS 3/13/2013 NS
MW-03 (Class III)NS 3/12/2013 NS
MW-01 (Class II)NS 3/12/2013 NS
2/20/2013 3/20/2013
1/23/2013MW-30 (Class II)2/26/2013 3/20/2013
Q1 2013 Results
MW-14 (Class III)1/23/2013 2/26/2013 3/20/2013
Required Quarterly Sampling Wells
Q2 2013 Results
4/16/2013 5/14/2013 6/25/2013
7/10/2013 8/20/2013 9/18/2013
7/11/2013 8/20/2013 9/19/2013
Q4 2013 Results
10/22/2013 11/19/2013 12/18/2013
4/17/2013
NS
NS
NS
5/21/2013
5/22/2013
5/23/2013
NS
NS
NS
APPENDIX A
GWCL Exceedances for Fourth Quarter 2013 Under the August 24, 2012 GWDP
Page 8 of 8
Appendix A
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
Monitoring Well
(Water Class)
Constituent
Exceeding GWCL
GWCL in August 24,
2012 GWDP
January 2013
Monthly Sample Date
January 2013
Monthly
Result
Q1 2013
Sample Date
Q1 2013
Result
March 2013 Monthly
Sample
Date
March 2013
Monthly Result
April 2013
Monthly Sample Date
April 2013
Monthly Result
Q2 2013
Sample Date
Q2 2013
Result
June 2013 Monthly
Sample
Date
June 2013
Monthly Result
Q3 2013
Sample Date
Q3 2013
Result
August
2013
Monthly Sample
Date
August 2013
Monthly
Result
September
2013
Monthly Sample
Date
September 2013
Monthly
Result
October 2013
Monthly
Sample Date
October 2013
Monthly
Result
Q4 2013
Sample Date
Q4 2013
Result
December
2013
Monthly Sample
Date
December 2013
Monthly
Result
Sample
Frequency
Q3 2013 ResultsQ1 2013 Results

Q2 2013 Results Q4 2013 Results
Field pH (S.U.)6.5 - 8.5 NA 6.56 NA NA 7.19 NA 6.60 NA NA NA 6.69 NA Semi-Annually
Selenium (ug/L)25 NA 19.6 NA NA 19.0 NA 20.5 NA NA NA 21.7 NA Semi-Annually
Selenium (ug/L)128.7 NA 137 NA NA 120 NA 100 NA NA NA 106 NA Semi-Annually
Field pH (S.U.)6.62 - 8.5 NA 6.75 NA NA 7.27 NA 6.68 NA NA NA 6.61 NA Semi-Annually
Iron (ug/L)81.7 NA <30 NA NA <30 NA <30 NA NA NA <30 NA Semi-Annually
Thallium (ug/l)1.95 NA 3.26 NA NA 2.81 NA 3.32 NA NA NA 3.06 NA Semi-Annually
Sulfate (mg/L)1938.9 NA 1270 NA NA 1860 NA 1860 NA NA NA 2000 NA Semi-Annually
Field pH (S.U.)6.25-8.5 NA 6.35 NA NA 6.97 NA 6.45 NA NA NA 6.38 NA Semi-Annually
TDS (mg/L)3198.77 NA 3350 NA NA 3160 NA 3170 NA NA NA 3240 NA Semi-Annually
Field pH (S.U.)6.78-8.5 NA 6.50 NA NA 7.16 NA 6.91 NA NA NA 6.58 NA Semi-Annually
Gross Alpha minus
Rn & U (pCi/L)2.36 NA 1.11 NA NA 1.19 NA <1.00 NA NA NA <1.00 NA Semi-Annually
Nitrate + Nitrite (as
N) (mg/L)2.83 NA 3.61 NA NA 4.21 NA 3.66 NA NA NA 3.70 NA Semi-Annually
Field pH (S.U.)6.5 - 8.5 NA 6.37 NA NA 7.23 NA 6.61 NA NA NA 7.21 NA Semi-Annually
Manganese (ug/L)550 NA 137 NA NA 24.3 NA 129 NA NA NA 19.2 NA Semi-Annually
Cadmium (ug/L)2.5 NA 2.0 NA NA 1.32 NA 6.72 NA NA NA 1.15 NA Semi-Annually
Fluoride (Mg/L)0.36 NA 0.355 NA NA 0.211 NA 0.288 NA NA NA 0.310 NA
Thallium (ug/L)1 NA 0.88 NA NA 0.618 NA 1.64 NA NA NA 0.707 NA Semi-Annually
Field pH (S.U.)6.5 - 8.5 NA 6.29 NA NA 6.77 NA 5.80 NA NA NA 6.08 NA Semi-Annually
Nitrate + Nitrite (as
N) (mg/L)5.6 NA 7.94 NA NA 7.09 NA 6.97 NA NA NA 7.89 NA Semi-Annually
Chloride (mg/L)38 NA 50.3 NA NA 44.3 NA 44.2 NA NA NA 45.0 NA Semi-Annually
Sulfate (mg/L)462 NA 431 NA NA 497 NA NA NA NA NA 442 NA Semi-Annually
Field pH (S.U.)6.5-8.5 NA 7.03 NA NA 7.58 NA 7.00 NA NA NA 7.16 NA Semi-Annually
TDS (mg/L)1075 NA 1140 NA NA 1110 NA 1110 NA NA NA 1100 NA Semi-Annually
Gross Alpha minus Rn & U (pCi/L)2 NA <1.0 NA NA 1.57 NA <1.00 NA NA NA 1.28 NA Semi-Annually
Chloride (mg/L)105 NA 110 NA NA 102 NA 107 NA NA NA 109 NA Semi-Annually
Manganese (ug/L)1837 NA 1680 NA NA 1730 NA 1650 NA NA NA 1530 NA Semi-Annually
Field pH (S.U.)6.1 - 8.5 NA 6.00 NA NA 6.63 NA 5.97 NA NA NA 6.10 NA Semi-Annually
Iron (ug/L)1869 NA 1350 NA NA 1250 NA 1400 NA NA NA 1690 NA Semi-Annually
Manganese (ug/L)5624 NA 5340 NA NA 5140 NA 5140 NA NA NA 5320 NA Semi-Annually
TDS (mg/L)4400 NA 4500 NA NA 4340 NA 4270 NA NA NA 4370 NA Semi-Annually
Field pH (S.U.)6.46 - 8.5 NA 6.36 NA NA 6.88 NA 6.37 NA NA NA 6.35 NA Semi-Annually
Gross Alpha minus Rn & U (pCi/L)3.33 NA 5.02 NA NA 3.72 NA 6.46 NA NA NA 1.86 NA Semi-Annually
Field pH (S.U.)6.4 - 8.5 NA 6.52 NA NA 7.10 NA 6.39 NA NA NA 6.29 NA Semi-Annually
Notes:
Values in () parentheses are the field pH measurements for the resampled analyses.
* Data are reported from the 6/5/13 chlorofrm program sample.
This constituent was removed from accelerated monitoring pursuant to the DRC letter dated November 14, 2013. The constituent exceeded the GWCL in the 4th quarter sample and will be sampled monthly beginning on or before March 2014.
Pursuant to the RC letter of November 14, 2013, these constituents will no longer be monitored on an accelerated schedule. These constituents will be dropped from this report after this quarter.
GWCL values are taken from August 24, 2012 version of GWDP.
NS = Not Required and Not Sampled
NR = Required and Not Reported
NA = Not Applicable
Exceedances are shown in yellow
NS 12/4/2013 NS
NS 11/20/2013 NS
NS 11/18/2013 NS
NS
12/18/2013 NS
NS 12/12/2013 NS
NS 12/4/2013 NS
MW-32 (Class III)NS 2/19/2013 NS
MW-29 (Class III)NS 3/6/2013 NS
MW-28 (Class III)NS 3/5/2013 NS
MW-27 (Class III)NS 2/25/2013 NS
MW-24 (Class III)NS 3/13/2013 NS
MW-23 (Class III)NS 3/11/2013
NS 12/9/2013 NS
NS 11/20/2013 NS
NS
MW-19 (Class III)NS 3/13/2013 NS
MW-18 (Class III)NS 2/25/2013 NS
NS
7/15/2013 NS NS
7/15/2013 NS NS
NS
NS
NS NS
7/17/2013 NS NS
7/18/2013
MW-12 (Class III)NS 3/6/2013 NS
MW-15 (Class III)NS 3/5/2013 NS
NS
NS
12/3/2013
12/3/2013 NS
NS
NS
NS
NS
NS
NS
NS
NS
5/15/2013
5/15/2013
5/20/2013
NS
NS
NS
NS
NS
NS
NS
NS
5/20/2013
5/23/2013
5/22/2013
5/21/2013
5/15/2013
Required Semi-Annual Sampling Wells (continued)
7/17/2013 NS NS
7/9/2013 NS NS
7/18/2013 NS NS
7/19/2013 NS NS
7/17/2013 NS NS
NS
NS
NS
5/23/2013
5/13/2013
7/17/2013 NS

APPENDIX B
Geochemical Analysis for Sulfate in
MW-01 and TDS in MW-03A
Page 1 of 1
Appendix B-1
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
Appendix B-1: Summary of Geochemical Analysis for Sulfate in MW-01 and TDS in MW-03A
W p
MW-01 Sulfate (mg/L)86 0 678 60 0.956265 0.005397 No
MW-03A TDS (mg/L)30 0 5,640 194 0.958362 0.281129 Yes
r2 p S p
MW-01 Sulfate (mg/L)----1,657 0.000000 Yes Yes 846
MW-03A TDS (mg/L)0.300237 0.001722 ----Yes No 6,020
Well Constituent Mean + 2σ
Fractional
Approach
GWCL
BKG Rpt
Proposed
GWCL
Current
GWCL
Flowsheet
GWCL
Flowsheet
GWCL
Rationale
MW-01 Sulfate (mg/L)798 NA 838 838 846 HHV
MW-03A TDS (mg/L)6,028 NA 6,657 5,805 6,028 Mean +2σ
Notes:
a A regression test was performed on data that was determined to have normal or log-normal distribution
b The Mann-Kendall test was performed on data that are not normally or lognormally distributedσ = sigma
Distribution = Distribution as determined by the Shapiro-Wilk distribution test
Highest Historical Value = The highest observed value after extreme outliers are removed from data set (per Flowsheet)
GWCL = groundwater concentration limit
Mean = The arithmatic mean as determined for normally or log-normally distributed constituents
mg/L = milligrams per liter
N = number of valid data points
p = probability
r2 = The measure of how well the trendline fits the data where r2=1 represents a perfect fit.
S = Mann-Kendall statistic
Standard Deviation = The standard deviation as determined for normally or log-normally distributed constituents
W = Shapiro Wilk test value
Well Constituent
Shapiro-Wilk Test for
Normality Normally or
Lognormally
Distributed?
Least Squares
Regression Trend
Analysisa Significant
Increasing
Trend
Previously
Identified
Increasing
Trend?
Highest
Historical
Value (HHV)
Standard
Deviation
Mann-Kendall Trend
Analysisb
Well Constituent N
% Non-
Detected
Values Mean
Appendix B-2: Comparison of Calculated and Measured TDS in MW-01 and MW-03A
Well Date Sampled
Alkalinity
(mg/L)
Calcium
(mg/L)
Chloride
(mg/L)
Potassium
(mg/L)
Magnesium
(mg/L)
Sodium
(mg/L)
Sulfate
(mg/L)
Measured
TDS (mg/L)
Calculated
TDS (mg/L)Ratio
MW-01 1/31/1980 281 110 14 8.5 39 130 520 882 1,103 1.25
MW-01 5/19/1980 293 148 20 11 44 165 635 1,275 1,316 1.03
MW-01 6/16/1980 295 156 16 8 39 166 632 1,276 1,312 1.03
MW-01 7/16/1980 329 141 20 17 54 160 610 1,182 1,331 1.13
MW-01 8/19/1980 329 132 18 17 54 158 612 1,220 1,320 1.08
MW-01 9/1/1980 317 144 13 12 59 156 640 1,285 1,341 1.04
MW-01 10/1/1980 317 148 30 15 39 162 570 1,220 1,281 1.05
MW-01 11/13/1980 299 139 12 9 40 166 613 1,166 1,278 1.10
MW-01 12/10/1980 305 135 13 9 49 168 620 1,194 1,299 1.09
MW-01 1/22/1981 309 146 15 10 47 170 638 1,273 1,335 1.05
MW-01 3/19/1981 323 146 14 9 53 175 658 1,317 1,378 1.05
MW-01 4/14/1981 329 140 13 10 56 161 620 1,330 1,329 1.00
MW-01 6/18/1981 317 156 12 10 46 162 626 1,188 1,329 1.12
MW-01 8/14/1981 353 156 14 10 51 161 630 1,197 1,375 1.15
MW-01 1/28/1982 325 142 13 14 55 170 613 1,199 1,332 1.11
MW-01 11/30/2000 317 138 15.2 5.9 50.8 156 608 1,270 1,291 1.02
MW-01 11/6/2001 306 158 17.3 6 59.2 158 691 1,360 1,396 1.03
MW-01 6/20/2005 298 123 11 5.8 51.8 166 637 1,220 1,293 1.06
MW-01 6/25/2006 299 153 17 6.6 60.5 157 724 1,320 1,417 1.07
MW-01 6/4/2008 286 164 15 6.92 59.5 174 726 1,220 1,431 1.17
MW-01 11/4/2008 297 169 12 6.89 60.7 176 719 1,300 1,441 1.11
MW-01 5/27/2009 304 165 16 6.4 63.1 158 744 1,330 1,457 1.10
MW-01 10/19/2009 308 155 17 6.4 58.1 164 741 1,330 1,450 1.09
MW-01 5/5/2010 313 161 18 6.77 57.4 177 805 1,340 1,538 1.15
MW-01 11/18/2010 303 175 15 6.8 61.6 169 792 1,350 1,522 1.13
MW-01 4/11/2011 299 173 18 7.1 60.6 175 704 1,410 1,437 1.02
MW-01 10/11/2011 278 169 17 6.4 60.6 155 713 1,370 1,399 1.02
MW-01 5/1/2012 297 166 18 7.9 60.5 155 659 1,410 1,363 0.97
MW-01 11/27/2012 293 174 18.5 6.85 63.3 178 846 1,340 1,579 1.18
MW-01 5/21/2013 300 160 17.8 6.66 60.3 160 839 1,420 1,544 1.09
MW-01 12/4/2013 287 191 18.7 6.97 64.3 176 930 1,440 1,673 1.16
MW-03A 6/25/2006 375 443 61 30.2 282 679 3,510 5,700 5,380 0.94
MW-03A 5/28/2008 384 496 61 28.6 306 827 3,550 5,070 5,653 1.11
MW-03A 11/3/2008 287 498 56 28.6 310 811 3,570 5,600 5,561 0.99
Page 1 of 2
Appendix B-2
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
You created this PDF from an application that is not licensed to print to novaPDF printer (http://www.novapdf.com)
Well Date Sampled
Alkalinity
(mg/L)
Calcium
(mg/L)
Chloride
(mg/L)
Potassium
(mg/L)
Magnesium
(mg/L)
Sodium
(mg/L)
Sulfate
(mg/L)
Measured
TDS (mg/L)
Calculated
TDS (mg/L)Ratio
MW-03A 2/9/2009 265 481 49 28.6 320 761 3,730 5,690 5,635 0.99
MW-03A 5/28/2009 306 436 60 28.1 303 674 3,640 5,660 5,447 0.96
MW-03A 8/18/2009 305 486 57 28.6 308 764 3,840 5,760 5,789 1.00
MW-03A 10/28/2009 424 478 42 28 298 773 3,870 5,570 5,913 1.06
MW-03A 5/4/2010 436 487 57 28.2 302 840 3,680 5,860 5,830 0.99
MW-03A 11/22/2010 346 463 59 27.8 312 754 3,850 5,330 5,812 1.09
MW-03A 4/13/2011 375 473 65 28.6 295 814 3,350 5,720 5,401 0.94
MW-03A 10/11/2011 376 474 59 27.3 301 708 3,750 5,630 5,695 1.01
MW-03A 5/15/2012 386 477 62 33.5 305 748 3,220 5,730 5,232 0.91
MW-03A 11/29/2012 396 469 67.1 28.1 295 818 2,780 5,610 4,853 0.87
MW-03A 5/23/2013 435 436 55.9 25.4 280 789 3,120 6,020 5,142 0.85
MW-03A 12/11/2013 384 446 60.9 27.8 296 781 3,360 5,940 5,356 0.90
Notes:
mg/L = milligrams per liter
Page 2 of 2
Appendix B-2
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
You created this PDF from an application that is not licensed to print to novaPDF printer (http://www.novapdf.com)
Page 1 of 1
Appendix B-3
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
Appendix B-3: Charge Balance Calcultions for Major Cations and Anions in MW-32
Well Date
Calcium
(meq/L)
Sodium
(meq/L)
Magnesium
(meq/L)
Potassium
(meq/L)
Total
Cation
Charge
(meq/L)
HCO3
(meq/L)
Chloride
(meq/L)
SO4
(meq/L)
Total Anion
Charge
(meq/L)
Percent
Difference
MW-01 1/31/1980 5.49 5.65 3.21 0.22 14.57 4.61 0.39 10.83 15.83 -8.27%
MW-01 5/19/1980 7.39 7.18 3.62 0.28 18.46 4.80 0.56 13.22 18.59 -0.67%
MW-01 6/16/1980 7.78 7.22 3.21 0.20 18.42 4.83 0.45 13.16 18.44 -0.14%
MW-01 7/16/1980 7.04 6.96 4.44 0.43 18.87 5.39 0.56 12.70 18.66 1.15%
MW-01 8/19/1980 6.59 6.87 4.44 0.43 18.34 5.39 0.51 12.74 18.64 -1.65%
MW-01 9/1/1980 7.19 6.79 4.85 0.31 19.13 5.20 0.37 13.33 18.89 1.29%
MW-01 10/1/1980 7.39 7.05 3.21 0.38 18.02 5.20 0.85 11.87 17.91 0.64%
MW-01 11/13/1980 6.94 7.22 3.29 0.23 17.68 4.90 0.34 12.76 18.00 -1.81%
MW-01 12/10/1980 6.74 7.31 4.03 0.23 18.31 5.00 0.37 12.91 18.27 0.17%
MW-01 1/22/1981 7.29 7.39 3.87 0.26 18.80 5.06 0.42 13.28 18.77 0.17%
MW-01 3/19/1981 7.29 7.61 4.36 0.23 19.49 5.29 0.39 13.70 19.39 0.51%
MW-01 4/14/1981 6.99 7.00 4.61 0.26 18.85 5.39 0.37 12.91 18.67 0.99%
MW-01 6/18/1981 7.78 7.05 3.78 0.26 18.87 5.20 0.34 13.03 18.57 1.62%
MW-01 8/14/1981 7.78 7.00 4.20 0.26 19.24 5.78 0.39 13.12 19.30 -0.30%
MW-01 9/1/1981 1.90 1.00 1.56 0.13 4.59 3.72 0.03 0.79 4.54 1.06%
MW-01 1/28/1982 7.09 7.39 4.52 0.36 19.36 5.33 0.37 12.76 18.46 4.80%
MW-01 11/30/2000 6.89 6.79 4.18 0.15 18.00 5.20 0.43 12.66 18.28 -1.55%
MW-01 11/6/2001 7.88 6.87 4.87 0.15 19.78 5.01 0.49 14.39 19.89 -0.55%
Page 1 of 1
Appendix B-4
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
Appendix B-4: Descriptive Statistics
Well Constituent Mean N Minimum Maximum
Standard
Deviation Range
Geometric
Mean Skewness Kurtosis Q25 Median Q75
MW-01 Sulfate 678 86 520 846 60 326 676 0.518 1.423 640 677 700
MW-03A TDS 5,640 30 5,070 6,020 194 950 5,636 -0.716 1.441 5,540 5,675 5,760
Notes:
N = number of sample results in data set used for analysis
Page 1 of 3
Appendix B-5
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
Appendix B-5: Data Used in Statistical Analysis
Location ID Date Sampled Parameter Name
Report
Result
Report
Units
MW-01 1/31/1980 Sulfate 520 mg/L
MW-01 4/30/1980 Sulfate 520 mg/L
MW-01 5/19/1980 Sulfate 635 mg/L
MW-01 6/16/1980 Sulfate 632 mg/L
MW-01 7/16/1980 Sulfate 610 mg/L
MW-01 8/19/1980 Sulfate 612 mg/L
MW-01 9/1/1980 Sulfate 640 mg/L
MW-01 10/1/1980 Sulfate 570 mg/L
MW-01 11/13/1980 Sulfate 613 mg/L
MW-01 12/10/1980 Sulfate 620 mg/L
MW-01 1/22/1981 Sulfate 638 mg/L
MW-01 2/12/1981 Sulfate 600 mg/L
MW-01 3/19/1981 Sulfate 658 mg/L
MW-01 4/14/1981 Sulfate 620 mg/L
MW-01 6/18/1981 Sulfate 626 mg/L
MW-01 8/14/1981 Sulfate 630 mg/L
MW-01 1/28/1982 Sulfate 613 mg/L
MW-01 4/13/1982 Sulfate 697 mg/L
MW-01 8/4/1982 Sulfate 662 mg/L
MW-01 12/10/1982 Sulfate 653 mg/L
MW-01 4/22/1983 Sulfate 658 mg/L
MW-01 10/26/1983 Sulfate 675 mg/L
MW-01 2/29/1984 Sulfate 637 mg/L
MW-01 6/13/1984 Sulfate 680 mg/L
MW-01 12/4/1984 Sulfate 626 mg/L
MW-01 6/28/1985 Sulfate 816 mg/L
MW-01 9/30/1985 Sulfate 779 mg/L
MW-01 3/27/1986 Sulfate 692 mg/L
MW-01 6/26/1986 Sulfate 691 mg/L
MW-01 9/4/1986 Sulfate 707 mg/L
MW-01 12/10/1986 Sulfate 680 mg/L
MW-01 2/20/1987 Sulfate 657 mg/L
MW-01 4/28/1987 Sulfate 664 mg/L
MW-01 8/14/1987 Sulfate 691 mg/L
MW-01 11/20/1987 Sulfate 697 mg/L
MW-01 1/27/1988 Sulfate 690 mg/L
MW-01 6/1/1988 Sulfate 681 mg/L
MW-01 8/23/1988 Sulfate 648 mg/L
MW-01 11/2/1988 Sulfate 688 mg/L
MW-01 11/15/1989 Sulfate 697 mg/L
MW-01 2/16/1990 Sulfate 692 mg/L
MW-01 5/8/1990 Sulfate 684 mg/L
MW-01 8/7/1990 Sulfate 685 mg/L
MW-01 11/13/1990 Sulfate 687 mg/L
MW-01 2/27/1991 Sulfate 662 mg/L
Page 2 of 3
Appendix B-5
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
Location ID Date Sampled Parameter Name
Report
Result
Report
Units
MW-01 5/21/1991 Sulfate 652 mg/L
MW-01 9/24/1991 Sulfate 692 mg/L
MW-01 12/3/1991 Sulfate 677 mg/L
MW-01 3/17/1992 Sulfate 667 mg/L
MW-01 6/11/1992 Sulfate 642 mg/L
MW-01 9/3/1992 Sulfate 670 mg/L
MW-01 12/9/1992 Sulfate 654 mg/L
MW-01 3/24/1993 Sulfate 614 mg/L
MW-01 6/8/1993 Sulfate 676 mg/L
MW-01 9/22/1993 Sulfate 658 mg/L
MW-01 12/14/1993 Sulfate 752 mg/L
MW-01 3/24/1994 Sulfate 722 mg/L
MW-01 6/15/1994 Sulfate 670 mg/L
MW-01 8/18/1994 Sulfate 700 mg/L
MW-01 12/13/1994 Sulfate 706 mg/L
MW-01 3/16/1995 Sulfate 683 mg/L
MW-01 9/20/1995 Sulfate 688 mg/L
MW-01 3/28/1996 Sulfate 641 mg/L
MW-01 6/7/1996 Sulfate 690 mg/L
MW-01 9/16/1996 Sulfate 658 mg/L
MW-01 3/20/1997 Sulfate 640 mg/L
MW-01 5/11/1999 Sulfate 645 mg/L
MW-01 11/30/2000 Sulfate 608 mg/L
MW-01 11/6/2001 Sulfate 691 mg/L
MW-01 6/20/2005 Sulfate 637 mg/L
MW-01 12/14/2005 Sulfate 702 mg/L
MW-01 6/25/2006 Sulfate 724 mg/L
MW-01 10/27/2006 Sulfate 838 mg/L
MW-01 10/31/2007 Sulfate 753 mg/L
MW-01 6/4/2008 Sulfate 726 mg/L
MW-01 11/4/2008 Sulfate 719 mg/L
MW-01 5/27/2009 Sulfate 744 mg/L
MW-01 10/19/2009 Sulfate 741 mg/L
MW-01 5/5/2010 Sulfate 805 mg/L
MW-01 11/18/2010 Sulfate 792 mg/L
MW-01 4/11/2011 Sulfate 704 mg/L
MW-01 10/11/2011 Sulfate 713 mg/L
MW-01 5/1/2012 Sulfate 659 mg/L
MW-01 11/27/2012 Sulfate 846 mg/L
MW-01 3/12/2013 Sulfate 761 mg/L
MW-01 5/21/2013 Sulfate 839 mg/L
MW-03A 5/5/2010 Total Dissolved Solids 5540 mg/L
MW-03A 11/18/2010 Total Dissolved Solids 5560 mg/L
MW-03A 4/11/2011 Total Dissolved Solids 5360 mg/L
MW-03A 10/11/2011 Total Dissolved Solids 5410 mg/L
MW-03A 5/1/2012 Total Dissolved Solids 5700 mg/L
Page 3 of 3
Appendix B-5
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
Location ID Date Sampled Parameter Name
Report
Result
Report
Units
MW-03A 11/27/2012 Total Dissolved Solids 5580 mg/L
MW-03A 5/21/2013 Total Dissolved Solids 5520 mg/L
MW-03A 12/4/2013 Total Dissolved Solids 5770 mg/L
MW-03A 10/31/1979 Total Dissolved Solids 5490 mg/L
MW-03A 1/31/1980 Total Dissolved Solids 5070 mg/L
MW-03A 4/30/1980 Total Dissolved Solids 5600 mg/L
MW-03A 5/19/1980 Total Dissolved Solids 5690 mg/L
MW-03A 6/16/1980 Total Dissolved Solids 5660 mg/L
MW-03A 7/16/1980 Total Dissolved Solids 5760 mg/L
MW-03A 8/19/1980 Total Dissolved Solids 5570 mg/L
MW-03A 9/1/1980 Total Dissolved Solids 5860 mg/L
MW-03A 10/1/1980 Total Dissolved Solids 5470 mg/L
MW-03A 11/13/1980 Total Dissolved Solids 5330 mg/L
MW-03A 12/10/1980 Total Dissolved Solids 5770 mg/L
MW-03A 1/22/1981 Total Dissolved Solids 5720 mg/L
MW-03A 2/12/1981 Total Dissolved Solids 5810 mg/L
MW-03A 3/19/1981 Total Dissolved Solids 5630 mg/L
MW-03A 4/14/1981 Total Dissolved Solids 5690 mg/L
MW-03A 6/18/1981 Total Dissolved Solids 5730 mg/L
MW-03A 9/1/1981 Total Dissolved Solids 5720 mg/L
MW-03A 12/28/1981 Total Dissolved Solids 5610 mg/L
MW-03A 1/28/1982 Total Dissolved Solids 5750 mg/L
MW-03A 5/11/1999 Total Dissolved Solids 6020 mg/L
MW-03A 11/30/2000 Total Dissolved Solids 5860 mg/L
MW-03A 11/6/2001 Total Dissolved Solids 5940 mg/L
Notes:
mg/L = milligrams per liter
Page 1 of 1
Appendix B-6
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
Appendix B-6: Data Omitted from Statistical Analysis
Location
ID
Date
Sampled
Parameter
Name
Report
Result
Report
Units Reason Removed
MW-01 10/31/1979 Sulfate 220 mg/L Extreme outlier
MW-01 9/1/1981 Sulfate 38 mg/L Extreme outlier
MW-01 12/15/1985 Sulfate 1,080 mg/L Extreme outlier
MW-01 2/20/1987 Sulfate 665 mg/L Duplicate sample
MW-01 4/29/1987 Sulfate 664 mg/L Duplicate sample
MW-01 8/19/1987 Sulfate 691 mg/L Duplicate sample
MW-01 11/2/1988 Sulfate 695 mg/L Duplicate sample
MW-01 9/1/1989 Sulfate 352 mg/L Extreme outlier
MW-01 3/24/1994 Sulfate 702 mg/L Duplicate sample
MW-01 6/28/1995 Sulfate 1,038 mg/L Extreme outlier
MW-01 9/9/2002 Sulfate 4,410 mg/L Extreme outlier/Duplicate Sample
MW-01 9/9/2002 Sulfate 662 mg/L Duplicate sample
MW-01 6/25/2006 Sulfate 699 mg/L Duplicate sample
MW-01 7/23/2013 Sulfate 911 mg/L Extreme outlier
MW-01 12/4/2013 Sulfate 930 mg/L Extreme outlier
Notes:
mg/L = milligrams per liter
Page 1 of 1
Appendix B-7
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
Appendix B-7: Box Plots
MW-03A
TDS in MW-03A
5000
5200
5400
5600
5800
6000
6200
TD
S

(
m
g
/
L
)
Median 25%-75% 1%-99% Outliers Extremes
Sulfate in MW-01
-200
0
200
400
600
800
1000
1200
Su
l
f
a
t
e

(
m
g
/
L
)
Median
25%-75%
1%-99%
Outliers
Extremes
Page 1 of 1
Appendix B-8
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
Appendix B-8: Histograms
TDS in MW-3A
SW-W = 0.9584, p = 0.2811
3.69 3.70 3.71 3.72 3.73 3.74 3.75 3.76 3.77 3.78 3.79
Log_Result
0
1
2
3
4
5
6
7
8
9
10
No

o
f

o
b
s
Sulfate in MW-01
SW-W = 0.9563, p = 0.0054
2.68 2.70 2.72 2.74 2.76 2.78 2.80 2.82 2.84 2.86 2.88 2.90 2.92 2.94 2.96
Log_Result
0
2
4
6
8
10
12
14
16
18
20
22
24
No

o
f

o
b
s
Page 1 of 1
Appendix B-9
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
Appendix B-9: Linear Regression
Linear Regression for Total Dissolved Solids in MW-3A
r = 0.5479, p = 0.0017; r2 = 0.3002
1/14/2004
5/28/2005
10/10/2006
2/22/2008
7/6/2009
11/18/2010
4/1/2012
8/14/2013
12/27/2014
Date Sampled
5000
5200
5400
5600
5800
6000
6200
TD
S

(
m
g
/
L
)
Linear Regression for Sulfate in MW-01
r = 0.6342, p = 0.0000; r2 = 0.4022
8/28/1976 2/18/1982 8/11/1987 1/31/1993 7/24/1998 1/14/2004 7/6/2009 12/27/2014
Date Sampled
500
550
600
650
700
750
800
850
900
Su
l
f
a
t
e

(
m
g
/
L
)
Page 1 of 1
Appendix B-10
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
Mann-Kendall Trend Test Analysis
3/7/2014 5:33:06 PM
MK Data MW-01.wst
OFF
0.95
0.05
86
520
846
678.3
675.7
676.5
60.41
6.514
1657
1.645
268.1
6.178
3.247E-10
Appendix B-10: Mann-Kendall Trend Test for Constituents
Not Normally or Lognormally Distributed
Report Result-sulfate
Geometric Mean
Median
User Selected Options
Date/Time of Computation
From File
Standard Deviation
Full Precision
Confidence Coefficient
Level of Significance
General Statistics
Number of Values
Minimum
Maximum
Mean
SEM
Mann-Kendall Test
Test Value (S)
Critical Value (0.05)
trend at the specified level of significance.
Standard Deviation of S
Standardized Value of S
Approximate p-value
Statistically significant evidence of an increasing

APPENDIX C
Geochemical Analysis for Indicator Parameters in
MW-01 and MW-03A
Page 1 of 1
Appendix C-1
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
W p r2 p S p
MW-01 Chloride (mg/L)94 0 13.6 3.6 0.618 0.000 No ----671 0.01 Yes Increasing No
MW-01 Fluoride (mg/L)40 0 0.32 0.09 0.866 0.000 No -----64 0.23 No ----
MW-01 Sulfate (mg/L)86 0 678.3 60.4 0.956 0.005 No ----1,657 0.00 Yes Increasing Yes
MW-01 Uranium (µg/L)69 27 1.42 1.41 0.747 0.000 No -----919 0.00 Yes Decreasing Yes
MW-03A Chloride (mg/L)23 0 59.3 5.7 0.860 0.004 No -----27 0.25 No ----
MW-03A Fluoride (mg/L)23 4 1.15 0.32 0.382 0.000 No -----72 0.03 Yes Decreasing No
MW-03A Sulfate (mg/L)30 0 3,518.3 253.8 0.911 0.015 No -----15 0.40 No ----
MW-03A Uranium (µg/L)23 0 21.3 4.2 0.917 0.057 Yes 0.150 0.068 ----No ----
Notes:
a A regression test was performed on data that was determined to have normal or log-normal distribution
b The Mann-Kendall test was performed on data that are not normally or lognormally distributed
Distribution = Distribution as determined by the Shapiro-Wilk distribution test
Mean = The arithmatic mean as determined for normally or log-normally distributed constituents
µg/L = micrograms per liter
mg/L = milligrams per liter
N = number of valid data points
p = probability
r2 = The measure of how well the trendline fits the data where r2=1 represents a perfect fit.
S = Mann-Kendall statistic
Standard Deviation = The standard deviation as determined for normally or lognormally distributed constituents
W = Shapiro Wilk test value
Appendix C-1: Summary of Geochemical Analysis for Indicator Parameters in MW-01 and MW-03A
Well
Normally or
Lognormally
distributed?
Least Squares
Regression Trend
Analysisa
Significant
Trend
Previously
Identified
Increasing
Trend?Constituent N
% Non-
Detected
Values Mean
Standard
Deviation
Shapiro-Wilk Test
for Normality
Mann-Kendall Trend
Analysisb
Page 1 of 1
Appendix C-2
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
Well Parameter Mean N Minimum Maximum
Standard
Deviation Range
Geometric
Mean Skewness Kurtosis Q25 Median Q75
MW-01 Chloride (mg/L)13.61 94 1.00 25.00 3.58 24.00 12.83 -0.53 2.94 12.00 13.00 16.00
MW-01 Fluoride (mg/L)0.32 40 0.10 0.56 0.09 0.46 0.30 0.35 1.74 0.29 0.30 0.35
MW-01 Sulfate (mg/L)678.28 86 520.00 846.00 60.41 326.00 675.66 0.52 1.42 640.00 676.50 700.00
MW-01 Uranium (µg/L)1.42 69 0.00 6.00 1.41 6.00 0.81 1.34 0.98 0.30 1.00 2.00
MW-03A Chloride (mg/L)59.30 23 42.00 70.00 5.73 28.00 59.01 -1.14 3.18 57.00 60.00 62.00
MW-03A Fluoride (mg/L)1.15 23 0.02 1.60 0.32 1.58 1.00 -1.91 6.75 1.00 1.14 1.38
MW-03A Sulfate (mg/L)3,518.33 30 2,780.00 3,870.00 253.81 1,090.00 3,508.99 -1.03 1.29 3,380.00 3,555.00 3,700.00
MW-03A Uranium (µg/L)21.33 23 16.50 35.20 4.23 18.70 20.98 1.78 4.25 18.50 19.70 22.90
Notes:
µg/L = micrograms per liter
mg/L = milligrams per liter
N = number of sample results in data set used for analysis
Appendix C-2: Descriptive Statistics for Indicator Parameters
Page 1 of 9
Appendix C-3
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
Location
ID Date Sampled
Parameter
Name
Report
Result
Report
Units
Lab
Qualifier
MW-01 10/31/1979 Chloride 2.5 mg/L
MW-01 1/31/1980 Chloride 14 mg/L
MW-01 4/30/1980 Chloride 13 mg/L
MW-01 5/19/1980 Chloride 20 mg/L
MW-01 6/16/1980 Chloride 16 mg/L
MW-01 7/16/1980 Chloride 20 mg/L
MW-01 8/19/1980 Chloride 18 mg/L
MW-01 9/1/1980 Chloride 13 mg/L
MW-01 11/13/1980 Chloride 12 mg/L
MW-01 12/10/1980 Chloride 13 mg/L
MW-01 1/22/1981 Chloride 15 mg/L
MW-01 2/12/1981 Chloride 14 mg/L
MW-01 3/19/1981 Chloride 14 mg/L
MW-01 4/14/1981 Chloride 13 mg/L
MW-01 6/18/1981 Chloride 12 mg/L
MW-01 8/14/1981 Chloride 14 mg/L
MW-01 9/1/1981 Chloride 1 mg/L
MW-01 12/28/1981 Chloride 15 mg/L
MW-01 1/28/1982 Chloride 13 mg/L
MW-01 4/13/1982 Chloride 11.7 mg/L
MW-01 7/4/1982 Chloride 12 mg/L
MW-01 8/4/1982 Chloride 12.4 mg/L
MW-01 12/10/1982 Chloride 10.9 mg/L
MW-01 1/25/1983 Chloride 16 mg/L
MW-01 4/22/1983 Chloride 16.5 mg/L
MW-01 9/7/1983 Chloride 15 mg/L
MW-01 10/26/1983 Chloride 12.7 mg/L
MW-01 2/29/1984 Chloride 14 mg/L
MW-01 6/13/1984 Chloride 12 mg/L
MW-01 9/25/1984 Chloride 15 mg/L
MW-01 12/4/1984 Chloride 14 mg/L
MW-01 6/28/1985 Chloride 17 mg/L
MW-01 9/30/1985 Chloride 18 mg/L
MW-01 3/27/1986 Chloride 17 mg/L
MW-01 6/26/1986 Chloride 25 mg/L
MW-01 9/4/1986 Chloride 2 mg/L
MW-01 12/10/1986 Chloride 8.8 mg/L
MW-01 2/20/1987 Chloride 11 mg/L
MW-01 4/28/1987 Chloride 12.1 mg/L
MW-01 8/14/1987 Chloride 11 mg/L
MW-01 11/20/1987 Chloride 9.3 mg/L
MW-01 1/27/1988 Chloride 10 mg/L
MW-01 6/1/1988 Chloride 9.9 mg/L
Appendix C-3: MW-01 and MW-03A Indicator Parameter Data
Used in Statistical Analysis
Page 2 of 9
Appendix C-3
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
Location
ID Date Sampled
Parameter
Name
Report
Result
Report
Units
Lab
Qualifier
MW-01 8/23/1988 Chloride 13.2 mg/L
MW-01 11/2/1988 Chloride 11.8 mg/L
MW-01 9/1/1989 Chloride 10 mg/L
MW-01 11/15/1989 Chloride 11 mg/L
MW-01 2/16/1990 Chloride 11 mg/L
MW-01 5/8/1990 Chloride 12 mg/L
MW-01 8/7/1990 Chloride 11 mg/L
MW-01 11/13/1990 Chloride 12 mg/L
MW-01 2/27/1991 Chloride 12 mg/L
MW-01 5/21/1991 Chloride 12 mg/L
MW-01 9/24/1991 Chloride 11 mg/L
MW-01 12/3/1991 Chloride 13 mg/L
MW-01 3/17/1992 Chloride 13 mg/L
MW-01 6/11/1992 Chloride 10 mg/L
MW-01 9/3/1992 Chloride 11 mg/L
MW-01 12/9/1992 Chloride 13 mg/L
MW-01 3/24/1993 Chloride 14 mg/L
MW-01 6/8/1993 Chloride 12 mg/L
MW-01 9/22/1993 Chloride 12 mg/L
MW-01 12/14/1993 Chloride 18 mg/L
MW-01 3/24/1994 Chloride 15 mg/L
MW-01 6/15/1994 Chloride 13 mg/L
MW-01 8/18/1994 Chloride 16 mg/L
MW-01 12/13/1994 Chloride 16 mg/L
MW-01 3/16/1995 Chloride 14 mg/L
MW-01 9/20/1995 Chloride 11 mg/L
MW-01 3/28/1996 Chloride 12.1 mg/L
MW-01 6/7/1996 Chloride 13 mg/L
MW-01 9/16/1996 Chloride 11.8 mg/L
MW-01 3/20/1997 Chloride 11.8 mg/L
MW-01 5/11/1999 Chloride 12.7 mg/L
MW-01 11/30/2000 Chloride 15.2 mg/L
MW-01 11/6/2001 Chloride 17.3 mg/L
MW-01 9/9/2002 Chloride 13.6 mg/L
MW-01 6/20/2005 Chloride 11 mg/L
MW-01 12/14/2005 Chloride 13 mg/L
MW-01 6/25/2006 Chloride 17 mg/L
MW-01 10/27/2006 Chloride 19 mg/L
MW-01 10/31/2007 Chloride 17 mg/L
MW-01 6/4/2008 Chloride 15 mg/L
MW-01 11/4/2008 Chloride 12 mg/L
MW-01 5/27/2009 Chloride 16 mg/L
MW-01 10/19/2009 Chloride 17 mg/L
MW-01 5/5/2010 Chloride 18 mg/L
Page 3 of 9
Appendix C-3
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
Location
ID Date Sampled
Parameter
Name
Report
Result
Report
Units
Lab
Qualifier
MW-01 11/18/2010 Chloride 15 mg/L
MW-01 4/11/2011 Chloride 18 mg/L
MW-01 10/11/2011 Chloride 17 mg/L
MW-01 5/1/2012 Chloride 18 mg/L
MW-01 11/27/2012 Chloride 18.5 mg/L
MW-01 5/21/2013 Chloride 17.8 mg/L
MW-01 12/4/2013 Chloride 18.7 mg/L
MW-01 10/31/1979 Fluoride 0.56 mg/L
MW-01 1/31/1980 Fluoride 0.34 mg/L
MW-01 4/30/1980 Fluoride 0.24 mg/L
MW-01 5/19/1980 Fluoride 0.17 mg/L
MW-01 6/16/1980 Fluoride 0.3 mg/L
MW-01 7/16/1980 Fluoride 0.3 mg/L
MW-01 8/19/1980 Fluoride 0.3 mg/L
MW-01 9/1/1980 Fluoride 0.4 mg/L
MW-01 10/1/1980 Fluoride 0.36 mg/L
MW-01 11/13/1980 Fluoride 0.23 mg/L
MW-01 12/10/1980 Fluoride 0.36 mg/L
MW-01 1/22/1981 Fluoride 0.22 mg/L
MW-01 2/12/1981 Fluoride 0.3 mg/L
MW-01 3/19/1981 Fluoride 0.43 mg/L
MW-01 4/14/1981 Fluoride 0.15 mg/L
MW-01 6/18/1981 Fluoride 0.4 mg/L
MW-01 9/1/1981 Fluoride 0.3 mg/L
MW-01 12/28/1981 Fluoride 0.37 mg/L
MW-01 1/28/1982 Fluoride 0.51 mg/L
MW-01 5/11/1999 Fluoride 0.1 mg/L
MW-01 11/30/2000 Fluoride 0.34 mg/L
MW-01 11/6/2001 Fluoride 0.3 mg/L
MW-01 9/9/2002 Fluoride 0.3 mg/L
MW-01 6/20/2005 Fluoride 0.47 mg/L
MW-01 12/14/2005 Fluoride 0.32 mg/L
MW-01 6/25/2006 Fluoride 0.29 mg/L
MW-01 10/27/2006 Fluoride 0.42 mg/L
MW-01 10/31/2007 Fluoride 0.32 mg/L
MW-01 6/4/2008 Fluoride 0.31 mg/L
MW-01 11/4/2008 Fluoride 0.31 mg/L
MW-01 5/27/2009 Fluoride 0.3 mg/L
MW-01 10/19/2009 Fluoride 0.3 mg/L
MW-01 5/5/2010 Fluoride 0.26 mg/L
MW-01 11/18/2010 Fluoride 0.29 mg/L
MW-01 4/11/2011 Fluoride 0.29 mg/L
MW-01 10/11/2011 Fluoride 0.33 mg/L
MW-01 5/1/2012 Fluoride 0.29 mg/L
MW-01 11/27/2012 Fluoride 0.297 mg/L
MW-01 5/21/2013 Fluoride 0.317 mg/L
Page 4 of 9
Appendix C-3
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
Location
ID Date Sampled
Parameter
Name
Report
Result
Report
Units
Lab
Qualifier
MW-01 12/4/2013 Fluoride 0.302 mg/L
MW-01 1/31/1980 Sulfate 520 mg/L
MW-01 4/30/1980 Sulfate 520 mg/L
MW-01 5/19/1980 Sulfate 635 mg/L
MW-01 6/16/1980 Sulfate 632 mg/L
MW-01 7/16/1980 Sulfate 610 mg/L
MW-01 8/19/1980 Sulfate 612 mg/L
MW-01 9/1/1980 Sulfate 640 mg/L
MW-01 10/1/1980 Sulfate 570 mg/L
MW-01 11/13/1980 Sulfate 613 mg/L
MW-01 12/10/1980 Sulfate 620 mg/L
MW-01 1/22/1981 Sulfate 638 mg/L
MW-01 2/12/1981 Sulfate 600 mg/L
MW-01 3/19/1981 Sulfate 658 mg/L
MW-01 4/14/1981 Sulfate 620 mg/L
MW-01 6/18/1981 Sulfate 626 mg/L
MW-01 8/14/1981 Sulfate 630 mg/L
MW-01 1/28/1982 Sulfate 613 mg/L
MW-01 4/13/1982 Sulfate 697 mg/L
MW-01 8/4/1982 Sulfate 662 mg/L
MW-01 12/10/1982 Sulfate 653 mg/L
MW-01 4/22/1983 Sulfate 658 mg/L
MW-01 10/26/1983 Sulfate 675 mg/L
MW-01 2/29/1984 Sulfate 637 mg/L
MW-01 6/13/1984 Sulfate 680 mg/L
MW-01 12/4/1984 Sulfate 626 mg/L
MW-01 6/28/1985 Sulfate 816 mg/L
MW-01 9/30/1985 Sulfate 779 mg/L
MW-01 3/27/1986 Sulfate 692 mg/L
MW-01 6/26/1986 Sulfate 691 mg/L
MW-01 9/4/1986 Sulfate 707 mg/L
MW-01 12/10/1986 Sulfate 680 mg/L
MW-01 2/20/1987 Sulfate 657 mg/L
MW-01 4/28/1987 Sulfate 664 mg/L
MW-01 8/14/1987 Sulfate 691 mg/L
MW-01 11/20/1987 Sulfate 697 mg/L
MW-01 1/27/1988 Sulfate 690 mg/L
MW-01 6/1/1988 Sulfate 681 mg/L
MW-01 8/23/1988 Sulfate 648 mg/L
MW-01 11/2/1988 Sulfate 688 mg/L
MW-01 11/15/1989 Sulfate 697 mg/L
MW-01 2/16/1990 Sulfate 692 mg/L
MW-01 5/8/1990 Sulfate 684 mg/L
MW-01 8/7/1990 Sulfate 685 mg/L
MW-01 11/13/1990 Sulfate 687 mg/L
MW-01 2/27/1991 Sulfate 662 mg/L
Page 5 of 9
Appendix C-3
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
Location
ID Date Sampled
Parameter
Name
Report
Result
Report
Units
Lab
Qualifier
MW-01 5/21/1991 Sulfate 652 mg/L
MW-01 9/24/1991 Sulfate 692 mg/L
MW-01 12/3/1991 Sulfate 677 mg/L
MW-01 3/17/1992 Sulfate 667 mg/L
MW-01 6/11/1992 Sulfate 642 mg/L
MW-01 9/3/1992 Sulfate 670 mg/L
MW-01 12/9/1992 Sulfate 654 mg/L
MW-01 3/24/1993 Sulfate 614 mg/L
MW-01 6/8/1993 Sulfate 676 mg/L
MW-01 9/22/1993 Sulfate 658 mg/L
MW-01 12/14/1993 Sulfate 752 mg/L
MW-01 3/24/1994 Sulfate 722 mg/L
MW-01 6/15/1994 Sulfate 670 mg/L
MW-01 8/18/1994 Sulfate 700 mg/L
MW-01 12/13/1994 Sulfate 706 mg/L
MW-01 3/16/1995 Sulfate 683 mg/L
MW-01 9/20/1995 Sulfate 688 mg/L
MW-01 3/28/1996 Sulfate 641 mg/L
MW-01 6/7/1996 Sulfate 690 mg/L
MW-01 9/16/1996 Sulfate 658 mg/L
MW-01 3/20/1997 Sulfate 640 mg/L
MW-01 5/11/1999 Sulfate 645 mg/L
MW-01 11/30/2000 Sulfate 608 mg/L
MW-01 11/6/2001 Sulfate 691 mg/L
MW-01 6/20/2005 Sulfate 637 mg/L
MW-01 12/14/2005 Sulfate 702 mg/L
MW-01 6/25/2006 Sulfate 724 mg/L
MW-01 10/27/2006 Sulfate 838 mg/L D
MW-01 10/31/2007 Sulfate 753 mg/L D
MW-01 6/4/2008 Sulfate 726 mg/L D
MW-01 11/4/2008 Sulfate 719 mg/L D
MW-01 5/27/2009 Sulfate 744 mg/L D
MW-01 10/19/2009 Sulfate 741 mg/L D
MW-01 5/5/2010 Sulfate 805 mg/L D
MW-01 11/18/2010 Sulfate 792 mg/L D
MW-01 4/11/2011 Sulfate 704 mg/L D
MW-01 10/11/2011 Sulfate 713 mg/L D
MW-01 5/1/2012 Sulfate 659 mg/L D
MW-01 11/27/2012 Sulfate 846 mg/L
MW-01 3/12/2013 Sulfate 761 mg/L
MW-01 5/21/2013 Sulfate 839 mg/L
MW-01 6/20/1977 Uranium 0.0003 ug/L U
MW-01 10/31/1979 Uranium 2 ug/L
MW-01 4/30/1980 Uranium 4.3 ug/L
MW-01 5/19/1980 Uranium 4 ug/L
MW-01 6/16/1980 Uranium 1 ug/L
Page 6 of 9
Appendix C-3
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
Location
ID Date Sampled
Parameter
Name
Report
Result
Report
Units
Lab
Qualifier
MW-01 8/19/1980 Uranium 2 ug/L
MW-01 10/1/1980 Uranium 1 ug/L
MW-01 11/13/1980 Uranium 1 ug/L
MW-01 2/12/1981 Uranium 5 ug/L
MW-01 6/18/1981 Uranium 6 ug/L
MW-01 2/11/1982 Uranium 1 ug/L
MW-01 2/29/1984 Uranium 4.04 ug/L
MW-01 12/4/1984 Uranium 1.05 ug/L
MW-01 9/30/1985 Uranium 2.99 ug/L
MW-01 12/15/1985 Uranium 2.54 ug/L
MW-01 4/8/1986 Uranium 2.84 ug/L
MW-01 12/10/1986 Uranium 4.33 ug/L
MW-01 2/20/1987 Uranium 0.30 ug/L U
MW-01 4/29/1987 Uranium 1.5 ug/L
MW-01 8/19/1987 Uranium 3.58 ug/L
MW-01 1/27/1988 Uranium 2.69 ug/L
MW-01 6/1/1988 Uranium 1.04 ug/L
MW-01 11/2/1988 Uranium 1.8 ug/L
MW-01 3/9/1989 Uranium 1.49 ug/L
MW-01 6/21/1989 Uranium 2.99 ug/L
MW-01 9/1/1989 Uranium 1.34 ug/L
MW-01 11/29/1989 Uranium 0.30 ug/L U
MW-01 2/16/1990 Uranium 3.58 ug/L
MW-01 5/8/1990 Uranium 1.04 ug/L
MW-01 8/7/1990 Uranium 0.70 ug/L
MW-01 11/13/1990 Uranium 0.75 ug/L
MW-01 2/27/1991 Uranium 0.33 ug/L
MW-01 5/21/1991 Uranium 1.36 ug/L
MW-01 9/24/1991 Uranium 1.22 ug/L
MW-01 12/3/1991 Uranium 0.64 ug/L
MW-01 3/17/1992 Uranium 0.68 ug/L
MW-01 6/11/1992 Uranium 4.18 ug/L
MW-01 9/3/1992 Uranium 3.03 ug/L
MW-01 12/9/1992 Uranium 0.81 ug/L
MW-01 3/24/1993 Uranium 0.30 ug/L U
MW-01 6/8/1993 Uranium 3 ug/L
MW-01 9/22/1993 Uranium 2.01 ug/L
MW-01 12/14/1993 Uranium 0.30 ug/L U
MW-01 6/15/1994 Uranium 0.30 ug/L U
MW-01 8/18/1994 Uranium 0.30 ug/L U
MW-01 3/16/1995 Uranium 1.11 ug/L
MW-01 3/28/1996 Uranium 0.3 ug/L U
MW-01 6/7/1996 Uranium 1.5 ug/L
MW-01 9/16/1996 Uranium 0.3 ug/L U
MW-01 3/20/1997 Uranium 0.3 ug/L U
MW-01 5/11/1999 Uranium 0.4 ug/L
Page 7 of 9
Appendix C-3
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
Location
ID Date Sampled
Parameter
Name
Report
Result
Report
Units
Lab
Qualifier
MW-01 11/30/2000 Uranium 0.3 ug/L U
MW-01 6/20/2005 Uranium 0.3 ug/L U
MW-01 12/14/2005 Uranium 0.3 ug/L U
MW-01 6/25/2006 Uranium 0.47 ug/L
MW-01 10/27/2006 Uranium 0.61 ug/L
MW-01 10/31/2007 Uranium 0.94 ug/L
MW-01 6/4/2008 Uranium 1.08 ug/L
MW-01 11/4/2008 Uranium 0.49 ug/L
MW-01 5/27/2009 Uranium 0.37 ug/L
MW-01 10/19/2009 Uranium 0.3 ug/L U
MW-01 5/5/2010 Uranium 0.33 ug/L
MW-01 11/18/2010 Uranium 0.33 ug/L
MW-01 4/11/2011 Uranium 0.3 ug/L U
MW-01 10/11/2011 Uranium 0.3 ug/L U
MW-01 5/1/2012 Uranium 0.3 ug/L U
MW-01 11/27/2012 Uranium 0.3 ug/L U
MW-01 5/21/2013 Uranium 0.3 ug/L U
MW-01 12/4/2013 Uranium 0.385 ug/L
MW-03A 6/23/2005 Chloride 63 mg/L
MW-03A 9/25/2005 Chloride 64 mg/L
MW-03A 12/14/2005 Chloride 60 mg/L
MW-03A 3/27/2006 Chloride 56 mg/L
MW-03A 6/25/2006 Chloride 61 mg/L
MW-03A 9/19/2006 Chloride 70 mg/L
MW-03A 10/26/2006 Chloride 57 mg/L
MW-03A 3/14/2007 Chloride 62 mg/L
MW-03A 10/31/2007 Chloride 60 mg/L
MW-03A 5/28/2008 Chloride 61 mg/L
MW-03A 11/3/2008 Chloride 56 mg/L
MW-03A 2/9/2009 Chloride 49 mg/L
MW-03A 5/28/2009 Chloride 60 mg/L
MW-03A 8/18/2009 Chloride 57 mg/L
MW-03A 10/28/2009 Chloride 42 mg/L
MW-03A 5/4/2010 Chloride 57 mg/L
MW-03A 11/22/2010 Chloride 59 mg/L
MW-03A 4/13/2011 Chloride 65 mg/L
MW-03A 10/11/2011 Chloride 59 mg/L
MW-03A 5/15/2012 Chloride 62 mg/L
MW-03A 11/29/2012 Chloride 67.1 mg/L
MW-03A 5/23/2013 Chloride 55.9 mg/L
MW-03A 12/11/2013 Chloride 60.9 mg/L
MW-03A 6/23/2005 Fluoride 1.6 mg/L
MW-03A 9/25/2005 Fluoride 1.1 mg/L
MW-03A 12/14/2005 Fluoride 1.3 mg/L
MW-03A 3/27/2006 Fluoride 1.4 mg/L
MW-03A 6/25/2006 Fluoride 1.1 mg/L
Page 8 of 9
Appendix C-3
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
Location
ID Date Sampled
Parameter
Name
Report
Result
Report
Units
Lab
Qualifier
MW-03A 9/19/2006 Fluoride 0.02 mg/L U
MW-03A 10/26/2006 Fluoride 1.14 mg/L
MW-03A 3/14/2007 Fluoride 1.18 mg/L
MW-03A 10/31/2007 Fluoride 1.37 mg/L
MW-03A 5/28/2008 Fluoride 1 mg/L
MW-03A 11/3/2008 Fluoride 1.47 mg/L
MW-03A 2/9/2009 Fluoride 1.45 mg/L
MW-03A 5/28/2009 Fluoride 1.56 mg/L
MW-03A 8/18/2009 Fluoride 1.38 mg/L
MW-03A 10/28/2009 Fluoride 1 mg/L
MW-03A 5/4/2010 Fluoride 0.94 mg/L
MW-03A 11/22/2010 Fluoride 1.28 mg/L
MW-03A 4/13/2011 Fluoride 1.14 mg/L
MW-03A 10/11/2011 Fluoride 1.06 mg/L
MW-03A 5/15/2012 Fluoride 1.06 mg/L
MW-03A 11/29/2012 Fluoride 0.988 mg/L
MW-03A 5/23/2013 Fluoride 0.963 mg/L
MW-03A 12/11/2013 Fluoride 1.04 mg/L
MW-03A 6/23/2005 Sulfate 3380 mg/L
MW-03A 9/25/2005 Sulfate 3560 mg/L D
MW-03A 12/14/2005 Sulfate 3520 mg/L
MW-03A 3/27/2006 Sulfate 3490 mg/L D
MW-03A 6/25/2006 Sulfate 3510 mg/L D
MW-03A 9/19/2006 Sulfate 3440 mg/L
MW-03A 10/26/2006 Sulfate 3270 mg/L D
MW-03A 3/14/2007 Sulfate 3810 mg/L D
MW-03A 10/31/2007 Sulfate 3470 mg/L D
MW-03A 5/28/2008 Sulfate 3550 mg/L D
MW-03A 11/3/2008 Sulfate 3570 mg/L D
MW-03A 2/9/2009 Sulfate 3730 mg/L D
MW-03A 5/28/2009 Sulfate 3640 mg/L D
MW-03A 8/18/2009 Sulfate 3840 mg/L D
MW-03A 10/28/2009 Sulfate 3870 mg/L D
MW-03A 5/4/2010 Sulfate 3680 mg/L D
MW-03A 9/21/2010 Sulfate 3630 mg/L D
MW-03A 11/22/2010 Sulfate 3850 mg/L D
MW-03A 2/16/2011 Sulfate 3730 mg/L D
MW-03A 4/13/2011 Sulfate 3350 mg/L D
MW-03A 8/11/2011 Sulfate 3560 mg/L D
MW-03A 10/11/2011 Sulfate 3750 mg/L D
MW-03A 3/1/2012 Sulfate 3020 mg/L D
MW-03A 5/15/2012 Sulfate 3220 mg/L D
MW-03A 7/19/2012 Sulfate 3700 mg/L D
MW-03A 11/29/2012 Sulfate 2780 mg/L
MW-03A 3/13/2013 Sulfate 3480 mg/L
MW-03A 5/23/2013 Sulfate 3120 mg/L
Page 9 of 9
Appendix C-3
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
Location
ID Date Sampled
Parameter
Name
Report
Result
Report
Units
Lab
Qualifier
MW-03A 7/19/2013 Sulfate 3670 mg/L
MW-03A 12/11/2013 Sulfate 3360 mg/L
MW-03A 6/23/2005 Uranium 35.2 ug/L
MW-03A 9/25/2005 Uranium 19.7 ug/L
MW-03A 3/27/2006 Uranium 19.9 ug/L
MW-03A 6/25/2006 Uranium 28.2 ug/L
MW-03A 9/19/2006 Uranium 25.4 ug/L
MW-03A 10/26/2006 Uranium 24.2 ug/L
MW-03A 3/14/2007 Uranium 21.9 ug/L
MW-03A 10/31/2007 Uranium 22.9 ug/L
MW-03A 5/28/2008 Uranium 22.4 ug/L
MW-03A 8/12/2008 Uranium 19 ug/L
MW-03A 11/3/2008 Uranium 17.9 ug/L
MW-03A 2/9/2009 Uranium 16.5 ug/L
MW-03A 5/28/2009 Uranium 17 ug/L
MW-03A 8/18/2009 Uranium 17 ug/L
MW-03A 10/28/2009 Uranium 19.5 ug/L
MW-03A 5/4/2010 Uranium 19.5 ug/L
MW-03A 11/22/2010 Uranium 19.2 ug/L
MW-03A 4/13/2011 Uranium 19.7 ug/L
MW-03A 10/11/2011 Uranium 18.1 ug/L
MW-03A 5/15/2012 Uranium 22.1 ug/L
MW-03A 11/29/2012 Uranium 22.4 ug/L
MW-03A 5/23/2013 Uranium 18.5 ug/L
MW-03A 12/11/2013 Uranium 24.3 ug/L
Notes:
µg/L = micrograms per liter
mg/L = milligrams per liter
U = not detected above reporting limit
D = Sample was diluted and reporting limit increased, sample result is greater than the
increased reporting limit
Page 1 of 1
AppendixC-4
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
Location ID
Date
Sampled
Parameter
Name
Report
Result
Report
Units
Lab
Qualifier Reason Removed
MW-01 10/1/1980 Chloride 30 mg/L Extreme outlier
MW-01 12/15/1985 Chloride 53.2 mg/L Extreme outlier
MW-01 2/20/1987 Chloride 12 mg/L Duplicate sample
MW-01 4/29/1987 Chloride 12.1 mg/L Duplicate sample
MW-01 8/19/1987 Chloride 11 mg/L Duplicate sample
MW-01 11/2/1988 Chloride 13.1 mg/L Duplicate sample
MW-01 3/24/1994 Chloride 15 mg/L Duplicate sample
MW-01 6/28/1995 Chloride 30 mg/L Extreme outlier
MW-01 9/9/2002 Chloride 12.7 mg/L Duplicate sample
MW-01 6/25/2006 Chloride 17 mg/L Duplicate sample
MW-01 8/14/1981 Fluoride 0.57 mg/L Extreme outlier
MW-01 6/25/2006 Fluoride 0.33 mg/L Duplicate sample
MW-01 10/31/1979 Sulfate 220 mg/L Extreme outlier
MW-01 9/1/1981 Sulfate 38 mg/L Extreme outlier
MW-01 12/15/1985 Sulfate 1080 mg/L Extreme outlier
MW-01 2/20/1987 Sulfate 665 mg/L Duplicate sample
MW-01 4/29/1987 Sulfate 664 mg/L Duplicate sample
MW-01 8/19/1987 Sulfate 691 mg/L Duplicate sample
MW-01 11/2/1988 Sulfate 695 mg/L Duplicate sample
MW-01 9/1/1989 Sulfate 352 mg/L Extreme outlier
MW-01 3/24/1994 Sulfate 702 mg/L Duplicate sample
MW-01 6/28/1995 Sulfate 1038 mg/L Extreme outlier
MW-01 9/9/2002 Sulfate 4410 mg/L Extreme outlier/ duplicate sample
MW-01 9/9/2002 Sulfate 662 mg/L Duplicate sample
MW-01 6/25/2006 Sulfate 699 mg/L D Duplicate sample
MW-01 7/23/2013 Sulfate 911 mg/L Extreme outlier
MW-01 12/4/2013 Sulfate 930 mg/L Extreme outlier
MW-01 7/16/1980 Uranium 1 ug/L U Insensitive detection limit
MW-01 9/1/1980 Uranium 1 ug/L U Insensitive detection limit
MW-01 12/10/1980 Uranium 10 ug/L Extreme outlier
MW-01 1/22/1981 Uranium 11 ug/L Extreme outlier
MW-01 9/1/1981 Uranium 1 ug/L U Insensitive detection limit
MW-01 11/15/1989 Uranium 0.30 ug/L U Duplicate sample
MW-01 12/13/1994 Uranium 2 ug/L Duplicate sample
MW-01 12/13/1994 Uranium 5.06 ug/L Duplicate sample
MW-01 6/28/1995 Uranium 0.3 ug/L U Duplicate sample
MW-01 6/28/1995 Uranium 0.40 ug/L Duplicate sample
MW-01 9/20/1995 Uranium 3.9 ug/L Duplicate sample
MW-01 9/20/1995 Uranium 3.64 ug/L Duplicate sample
MW-01 12/11/1995 Uranium 1.2 ug/L Duplicate sample
MW-01 12/11/1995 Uranium 4.85 ug/L Duplicate sample
MW-01 11/6/2001 Uranium 1 ug/L U Insensitive detection limit
MW-03A 12/14/2005 Uranium 0.3 ug/L U Extreme outlier
Notes:
mg/L = milligrams per liter
ug/L = micrograms per liter
U = Not detected above reporting limit
Appendix C-4: MW-01 and MW-03A Indicator Parameter Data Omitted from Statistical Analysis
Page 1 of 2
Appendix C-5
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
Appendix C-5: Box Plots for Indicator Parameters
MW-01 MW-03A
Location ID
Chloride
-10
0
10
20
30
40
50
60
70
80
Ch
l
o
r
i
d
e

(
m
g
/
L
)
Median 25%-75% 1%-99% Outliers Extremes
MW-01 MW-03A
Location ID
Fluoride
-0.2
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
Fl
u
o
r
i
d
e

(
m
g
/
L
)
Median
25%-75%
1%-99%
Outliers
Extremes
Page 2 of 2
Appendix C-5
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
MW-01 MW-03A
Location ID
Sulfate
-500
0
500
1000
1500
2000
2500
3000
3500
4000
4500
Su
l
f
a
t
e

(
m
g
/
L
)
Median
25%-75%
1%-99%
Outliers
Extremes
MW-01 MW-03A
Location ID
Uranium
-5
0
5
10
15
20
25
30
35
40
Ur
a
n
i
u
m

(
u
g
/
L
)
Median
25%-75%
1%-99%
Outliers
Extremes
Page 1 of 4
Appendix C-6
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
Appendix C-6: Histograms for Indicator Parameters
Fluoride in MW-01
SW-W = 0.8663, p = 0.0002
-1.1 -1.0 -0.9 -0.8 -0.7 -0.6 -0.5 -0.4 -0.3 -0.2 -0.1
Log_Result
0
2
4
6
8
10
12
14
16
18
20
No

o
f

o
b
s
Chloride in MW-01
SW-W = 0.6181, p = 0.0000
-0.2 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6
Log_Result
0
10
20
30
40
50
60
70
No

o
f

o
b
s
Page 2 of 4
Appendix C-6
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
Sulfate in MW-01
SW-W = 0.9563, p = 0.0054
2.68 2.70 2.72 2.74 2.76 2.78 2.80 2.82 2.84 2.86 2.88 2.90 2.92 2.94 2.96
Log_Result
0
2
4
6
8
10
12
14
16
18
20
22
24
No

o
f

o
b
s
Uranium in MW-01
SW-W = 0.7471, p = 0.00000
-4.0 -3.5 -3.0 -2.5 -2.0 -1.5 -1.0 -0.5 0.0 0.5 1.0 1.5
Log_Result
0
2
4
6
8
10
12
14
16
18
20
22
24
No

o
f

o
b
s
Page 3 of 4
Appendix C-6
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
Chloride in MW-03A
SW-W = 0.8597, p = 0.0041
1.60 1.62 1.64 1.66 1.68 1.70 1.72 1.74 1.76 1.78 1.80 1.82 1.84 1.86 1.88
Log_Result
0
1
2
3
4
5
6
7
No

o
f

o
b
s
Fluoride in MW-03A
SW-W = 0.3825, p = 0.00000
-2.0 -1.8 -1.6 -1.4 -1.2 -1.0 -0.8 -0.6 -0.4 -0.2 0.0 0.2 0.4
Log_Result
0
2
4
6
8
10
12
14
16
18
No

o
f

o
b
s
Page 4 of 4
Appendix C-6
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
Sulfate in MW-03A
SW-W = 0.9106, p = 0.0154
3.42 3.44 3.46 3.48 3.50 3.52 3.54 3.56 3.58 3.60 3.62
Log_Result
0
2
4
6
8
10
12
No

o
f

o
b
s
Uranium in MW-03A
SW-W = 0.9168, p = 0.0570
1.15 1.20 1.25 1.30 1.35 1.40 1.45 1.50 1.55 1.60
Log_Result
0
2
4
6
8
10
12
No

o
f

o
b
s
Page 1 of 1
Appendix C-7
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
Appendix C-7: Linear Regressions for Lognormally or Normally
Distributed Constituents
Linear Regression for Uranium in MW-3A
r = -0.3874, p = 0.0678; r2 = 0.1501
1/14/2004
5/28/2005
10/10/2006
2/22/2008
7/6/2009
11/18/2010
4/1/2012
8/14/2013
12/27/2014
Date Sampled
14
16
18
20
22
24
26
28
30
32
34
36
Ur
a
n
i
u
m

(
u
g
/
L
)
Page 1 of 3
Appendix C-8
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
Mann-Kendall Trend Test Analysis
94
1
25
13.61
12.83
13
3.584
0.37
671
1.645
305.2
2.196
0.0141
40
0.1
0.56
0.317
0.305
0.3
0.0868
0.0137
-64
-1.645
85.24
-0.739
0.23
86
520
846
678.3
675.7
676.5
60.41
6.514
1657
1.645
268.1
6.178
3.247E-10
Statistically significant evidence of an increasing
trend at the specified level of significance.
Test Value (S)
Critical Value (0.05)
Standard Deviation of S
Standardized Value of S
Approximate p-value
Median
Standard Deviation
SEM
Mann-Kendall Test
Number of Values
Minimum
Maximum
Mean
Geometric Mean
Insufficient evidence to identify a significant
trend at the specified level of significance.
Report Result-sulfate, MW-01
General Statistics
Critical Value (0.05)
Standard Deviation of S
Standardized Value of S
Approximate p-value
Standard Deviation
SEM
Mann-Kendall Test
Test Value (S)
Minimum
Maximum
Mean
Geometric Mean
Median
trend at the specified level of significance.
Report Result-fluoride, MW-01
General Statistics
Number of Values
Standard Deviation of S
Standardized Value of S
Approximate p-value
Statistically significant evidence of an increasing
0.05
SEM
Mann-Kendall Test
Test Value (S)
Critical Value (0.05)
Maximum
Mean
Geometric Mean
Median
Standard Deviation
Appendix C-8: Mann-Kendall Trend Test for Constituents
User Selected Options
Date/Time of Computation 3/7/2014 5:33:06 PM
Report Result-chloride, MW-01
General Statistics
Number of Values
Minimum
Full Precision OFF
Confidence Coefficient 0.95
Level of Significance
Page 2 of 3
Appendix C-8
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
Mann-Kendall Trend Test Analysis
Appendix C-8: Mann-Kendall Trend Test for Constituents
User Selected Options
Date/Time of Computation 3/7/2014 5:33:06 PM
Full Precision OFF
Confidence Coefficient 0.95
69
0.0003
6
1.424
0.813
1
1.409
0.17
-919
-1.645
192.4
-4.771
9.157E-07
23
42
70
59.3
59.01
60
5.732
1.195
-27
-1.645
37.71
-0.689
0.245
23
0.0203
1.6
1.154
0.996
1.137
0.318
0.0663
-72
-1.645
37.82
-1.877
0.0303
trend at the specified level of significance.
Standard Deviation of S
Standardized Value of S
Approximate p-value
Statistically significant evidence of a decreasing
SEM
Mann-Kendall Test
Test Value (S)
Critical Value (0.05)
Maximum
Mean
Geometric Mean
Median
Standard Deviation
Report Result-fluoride, MW-03A
General Statistics
Number of Values
Minimum
Standardized Value of S
Approximate p-value
Insufficient evidence to identify a significant
trend at the specified level of significance.
Mann-Kendall Test
Test Value (S)
Critical Value (0.05)
Standard Deviation of S
Mean
Geometric Mean
Median
Standard Deviation
SEM
General Statistics
Number of Values
Minimum
Maximum
Approximate p-value
Statistically significant evidence of a decreasing
trend at the specified level of significance.
Report Result-chloride, MW-03A
Mann-Kendall Test
Test Value (S)
Critical Value (0.05)
Standard Deviation of S
Standardized Value of S
Geometric Mean
Median
Standard Deviation
SEM
General Statistics
Number of Values
Minimum
Maximum
Mean
Report Result-uranium, MW-01
Page 3 of 3
Appendix C-8
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
Mann-Kendall Trend Test Analysis
Appendix C-8: Mann-Kendall Trend Test for Constituents
User Selected Options
Date/Time of Computation 3/7/2014 5:33:06 PM
Full Precision OFF
Confidence Coefficient 0.95
30
2780
3870
3518
3509
3555
253.8
46.34
-15
-1.645
56.03
-0.25
0.401
Insufficient evidence to identify a significant
trend at the specified level of significance.
Critical Value (0.05)
Standard Deviation of S
Standardized Value of S
Approximate p-value
Standard Deviation
SEM
Mann-Kendall Test
Test Value (S)
Minimum
Maximum
Mean
Geometric Mean
Median
Report Result-sulfate, MW-03A
General Statistics
Number of Values

APPENDIX D
Time Concentration Plots Compared to Background Report Plots
Appendix D: Time Concentration Plots Compared to Background Report Plots
Page 1 of 9
Appendix D
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
SAR Trend Plot
Background Report Trend Plot
Linear Regression for Chloride in MW-1
100% Detected
r2 = 0.0036; r = 0.0598, p = 0.5846
8/28/76 2/18/82 8/11/87 1/31/93 7/24/98 1/14/04 7/6/09
Date
0
2
4
6
8
10
12
14
16
18
20
22
24
Ch
l
o
r
i
d
e

(
m
g
/
L
)
Detected Value
Non-Detected Value
Linear Regression for Chloride in MW-01
r = 0.3135, p = 0.0021; r2 = 0.0983
8/28/1976
2/18/1982
8/11/1987
1/31/1993
7/24/1998
1/14/2004
7/6/2009
12/27/2014
6/18/2020
Date Sampled
0
2
4
6
8
10
12
14
16
18
20
22
24
26
Ch
l
o
r
i
d
e

(
m
g
/
L
)
Appendix D: Time Concentration Plots Compared to Background Report Plots
Page 2 of 9
Appendix D
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
SAR Trend Plot
Background Report Trend Plot
Linear Regression for Fluoride in MW-1
100% Detected
r2 = 0.0016; r = -0.0400, p = 0.8400
8/28/76 2/18/82 8/11/87 1/31/93 7/24/98 1/14/04 7/6/09
Date
0.0
0.1
0.2
0.3
0.4
0.5
0.6
Fl
u
o
r
i
d
e

(
m
g
/
L
)
Detected Value
Non-Detected Value
Linear Regression for Fluoride in MW-01
r = -0.0992, p = 0.5425; r2 = 0.0098
8/28/1976
2/18/1982
8/11/1987
1/31/1993
7/24/1998
1/14/2004
7/6/2009
12/27/2014
6/18/2020
Date Sampled
0.05
0.10
0.15
0.20
0.25
0.30
0.35
0.40
0.45
0.50
0.55
0.60
Fl
u
o
r
i
d
e

(
m
g
/
L
)
Appendix D: Time Concentration Plots Compared to Background Report Plots
Page 3 of 9
Appendix D
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
SAR Trend Plot
Background Report Trend Plot
Linear Regression for Sulfate in MW-1
100% Detected
r2 = 0.1284; r = 0.3584, p = 0.0009
8/28/76 2/18/82 8/11/87 1/31/93 7/24/98 1/14/04 7/6/09
Date
300
400
500
600
700
800
900
Su
l
f
a
t
e

(
m
g
/
L
)
Detected Values
Non-Detect Values
Linear Regression for Sulfate in MW-01
r = 0.6342, p = 0.0000; r2 = 0.4022
8/28/1976 2/18/1982 8/11/1987 1/31/1993 7/24/1998 1/14/2004 7/6/2009 12/27/2014
Date Sampled
500
550
600
650
700
750
800
850
900
Su
l
f
a
t
e

(
m
g
/
L
)
Appendix D: Time Concentration Plots Compared to Background Report Plots
Page 4 of 9
Appendix D
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
SAR Trend Plot
Background Report Trend Plot
Linear Regression for Uranium in MW-1
75.3% Detected
r2 = 0.2150; r = -0.4637, p = 0.00002
8/28/76 2/18/82 8/11/87 1/31/93 7/24/98 1/14/04 7/6/09
Date
-2
0
2
4
6
8
10
12
Ur
a
n
i
u
m

(
u
g
/
L
)
Detected Values
Non-Detected Values
Linear Regression for Uranium in MW-01
r = -0.5388, p = 0.00000; r2 = 0.2903
3/8/1971
8/28/1976
2/18/1982
8/11/1987
1/31/1993
7/24/1998
1/14/2004
7/6/2009
12/27/2014
6/18/2020
Date Sampled
-1
0
1
2
3
4
5
6
7
Ur
a
n
i
u
m

(
u
g
/
L
)
Report Result
Non-Detect Result
Appendix D: Time Concentration Plots Compared to Background Report Plots
Page 5 of 9
Appendix D
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
SAR Trend Plot
Background Report Trend Plot
Linear Regression for Chloride in MW-3A
r = -0.0809, p = 0.7137; r2 = 0.0065
1/14/2004
5/28/2005
10/10/2006
2/22/2008
7/6/2009
11/18/2010
4/1/2012
8/14/2013
12/27/2014
Date Sampled
40
45
50
55
60
65
70
75
Ch
l
o
r
i
d
e

(
m
g
/
L
)
Linear Regression for Chloride in MW-3A
(100% Detected)
r2 = 0.0096; r = -0.0981, p = 0.8017
2/17/05 9/5/05 3/24/06 10/10/06 4/28/07 11/14/07
Date
54
56
58
60
62
64
66
68
70
72
Ch
l
o
r
i
d
e

(
m
g
/
L
)
Detected Values
Non-Detected Values
Appendix D: Time Concentration Plots Compared to Background Report Plots
Page 6 of 9
Appendix D
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
SAR Trend Plot
Background Report Trend Plot
Linear Regression for Fluoride in MW-3A
r = -0.1369, p = 0.5335; r2 = 0.0187
1/14/2004
5/28/2005
10/10/2006
2/22/2008
7/6/2009
11/18/2010
4/1/2012
8/14/2013
12/27/2014
Date Sampled
-0.2
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
Fl
u
o
r
i
d
e

(
m
g
/
L
)
Report Result
Non-Detected Value
Linear Regression for Fluoride in MW-3A
(100% Detected)
r2 = 0.1170; r = -0.3421, p = 0.3675
5/28/05 9/5/05 12/14/05 3/24/06 7/2/06 10/10/06 1/18/07 4/28/07
Date
-0.2
0.2
0.6
1.0
1.4
1.8
Fl
u
o
r
i
d
e

(
m
g
/
L
)
Detected Values
Non-Detected Values
Appendix D: Time Concentration Plots Compared to Background Report Plots
Page 7 of 9
Appendix D
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
SAR Trend Plot
Background Report Trend Plot
Linear Regression for Sulfate in MW-3A
r = -0.1912, p = 0.3114; r2 = 0.0366
1/14/2004
5/28/2005
10/10/2006
2/22/2008
7/6/2009
11/18/2010
4/1/2012
8/14/2013
12/27/2014
Date Sampled
2600
2800
3000
3200
3400
3600
3800
4000
Su
l
f
a
t
e

(
m
g
/
L
)
Linear Regression for Sulfate in MW-3A
(100% Detected)
r2 = 0.0366; r = -0.1913, p = 0.6501
2/17/05 9/5/05 3/24/06 10/10/06 4/28/07 11/14/07
Date
3200
3300
3400
3500
3600
3700
Su
l
f
a
t
e

(
m
g
/
L
)
Stat Results
Non-Detected Values
Appendix D: Time Concentration Plots Compared to Background Report Plots
Page 8 of 9
Appendix D
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
SAR Trend Plot
Background Report Trend Plot
Linear Regression for Uranium in MW-3A
r = -0.3874, p = 0.0678; r2 = 0.1501
1/14/2004
5/28/2005
10/10/2006
2/22/2008
7/6/2009
11/18/2010
4/1/2012
8/14/2013
12/27/2014
Date Sampled
14
16
18
20
22
24
26
28
30
32
34
36
Ur
a
n
i
u
m

(
u
g
/
L
)
Linear Regression for Uranium in MW-3A
(100% Detected)
r2 = 0.1354; r = -0.3680, p = 0.3697
2/17/05 9/5/05 3/24/06 10/10/06 4/28/07 11/14/07
Date
18
20
22
24
26
28
30
32
34
36
Ur
a
n
i
u
m

(
u
g
/
L
)
Detected Values
Non-Detected Values
Appendix D: Time Concentration Plots Compared to Background Report Plots
Page 9 of 9
Appendix D
Source Assessment Report for Sulfate in MW-01 and TDS in MW-03A
White Mesa Uranium Mill
SAR Trend Plot
Background Report Trend Plot
Linear Regression for Total Dissolved Solids in MW-3A
r = 0.5479, p = 0.0017; r2 = 0.3002
1/14/2004
5/28/2005
10/10/2006
2/22/2008
7/6/2009
11/18/2010
4/1/2012
8/14/2013
12/27/2014
Date Sampled
5000
5200
5400
5600
5800
6000
6200
TD
S

(
m
g
/
L
)
Linear Regression for TDS in MW-3A
(100% Detected)
r2 = 0.0767; r = 0.2770, p = 0.4706
2/17/05 9/5/05 3/24/06 10/10/06 4/28/07 11/14/07
Date
5300
5350
5400
5450
5500
5550
5600
5650
5700
5750
5800
TD
S

(
m
g
/
L
)
Detected Values
Non-Detected Values

APPENDIX E
Flowsheet (Groundwater Data Preparation and Statistical Process
Flow for Calculating Groundwater Protection Standards, White Mesa
Mill Site (INTERA, 2007))
Negative Value?
Zero Value?
Truncated Value?
Duplicate Value?
Units Consistant?
Non-detects Exceeding Criteria Specified by URS Memo*
Analysis Internally Consistent?(TDS and Charge Balance Check)
YesNo
No
Yes
No
No
No
Yes
Yes
No
Yes
Yes
Yes
Radionuclide?
Yes
Remove from DatasetDetection Limit and U-Flag Data Qualifier NoNo
Review for Units
Remove from Dataset
If chloride, sulfate, or TDS, Remove from Dataset
Correct Value Confirmed?
Remove from
Dataset
Remove from Dataset
Determine Percentage Non-Detects in Remaining Data
Plot Data Sets as Box Plots to Identify Extreme Values As Specified in Background Report. Extreme Value?
No Remove from
Dataset
Yes
At Least 8 Data Points Remaining?
Defer Analysis Until Eight
Data Points Avalible
0-15 Percent Non-Detects >15-50 Percent Non-Detects >90 Percent Non-Detects
No
Yes
No
Substitute One Half of Detection Limit
Log Transform Data
Use Probability Plots to
Determine if Cohen’s or Aitchison’s Method
Calculate Descriptive Statistics
(Redo Tables In Background Report)
Screen for Trends Using Least Squares Regression.
Calculate GWCL (Mean
+2Sigma)
Calculate Descriptive Statistics
(Redo Tables In Background Report)
Yes
No
Calculate GWCL (Mean +2Sigma)
Calculate GWCL Using Greater of Fraction Approach under UAC R317-6-4-4.5(B)(2) or 4.6(B)(2) or Poisson Prediction Limit
Yes
No
>50-90 Percent Non-Detects
Calculate Upper Prediction Limit (Highest Historical Value)
Calculate GWCL Using Greater of Fraction Approach under UAC R317-6-4-4.5(B)(2) or 4.6(B)(2) or the Highest Historic Value
Estimate Mean and Standard
Deviation
Screen for Trends Using Mann-Kendall Screen for Trends Using Mann-Kendall
Yes
Use Non-Parametric StatisticsNo
Screen for Trends Using Least Squares Regression
Groundwater Data Preparation and Statistical Process Flow for
Calculating Groundwater Protection Standards, White Mesa Mill Site, San Juan County, Utah
Upward Trend?Upward Trend?
No No
Yes
Consider Modified Approch to GWCL
Upward Trend?Upward Trend?
No No
Yes
Consider Modified Approch to GWCL
Log Transform Data
Log-Normal or Normal?Shapiro WilkProbability PlotsHistograms
Log-Normal or Normal?Shapiro WilkProbability PlotsHistograms
*A non-detect considered “insensitive” will be the maximum reporting limit in a dataset and will exceed other non-detects by, for example, an order of magnitude (e.g., <10 versus <1.0 µg/L). In some cases, insensitive non-detects may also exceed detectable values in a
dataset (e.g., <10 versus 3.5 µg/L).
Groundwater Data Preparation and Statistical Process Flow for Calculating Ground Water Compliance Limits, White Mesa Mill Site, SanJuan County, Utah.
Database of Wells and Analytes Listed in the Statement of Basis

APPENDIX F
Input and Output Files (Electronic Only)