DRC-2020-018845 - 0901a06880d8af15

Energy Fuels Resources (USA) Inc.
225 Union Blvd. Suite 600
Lakewood, CO, US, 80228
303 974 2140
www.energyfuels.com
D'RC-202,0-01551.1-5 Div of Waste Management and Radiation Control
NOV 2 0 2020
Ty L. Howard,
Director of Waste Management and Radiation Control
State of Utah Department of Environmental Quality
195 North 1950 West
P.O. Box 144880
Salt Lake City, UT 84114-4880
Re: Transmittal of Plan and Time Schedule under Utah Ground Water Discharge Permit
UGW370004 Part I.G.4 (c) White Mesa Mill (the "Mill")
Dear Mr. Howard:
This letter transmits Energy Fuels Resources (USA) Inc.'s ("EFRI's") Plan and Time Schedule pursuant to
State of Utah Groundwater Discharge Permit UGW370004 (the "Permit") Part I.G.4(c) for MW-12 and MW-31
for the third quarter of 2020. Part I.G.2 of the Permit provides that out-of-compliance ("00C") status exists
when the concentration of a pollutant in two consecutive samples from a compliance monitoring point exceeds
a groundwater compliance limit ("GWCL"). While consecutive exceedance have been noted in other wells at
the site, a plan and time schedule have not been required or appropriate in light of other actions currently being
undertaken by EFRI or in light of other reports submitted by EFRI.
This Plan covers selenium and uranium in MW-12 and uranium in MW-31 that was identified as being in
violation of Part 1.0.2 of the Permit, in the Third Quarter 2020 Exceedance Notice, dated October 20, 2020.
Please contact me if you have any questions or require any further information.
Yours very truly,
ENERGY FUELS RESOURCES (USA) INC.
Kathy Weinel
Quality Assurance Manager
cc: Scott Bakken
David Frydenlund
Garrin Palmer
Logan Shumway
Terry Slade
Angie Persico (Intera)
November 18, 2020
Sent VIA E-MAIL AND EXPRESS DELIVERY
WHITE MESA MILL
State of Utah Ground Water Discharge Permit UGW370004
Plan and Time Schedule
Under Part I.G.4 (c)
For
Exceedances in MW-31 and MW-12 in the Third Quarter of 2020
Energy Fuels Resources (USA) Inc.
225 Union Boulevard, Suite 600
Lakewood, CO 80228
November 18, 2020
1. INTRODUCTION
Energy Fuels Resources (USA) Inc. ("EFRI") operates the White Mesa Uranium Mill (the
"Mill"), located near Blanding Utah, under State of Utah Ground Water Discharge Permit
UGW370004 (the "Permit").
This is the plan and time schedule ("P&TS") required under Part I.G.4(c) of the Permit relating
to violations of Part I.G.2 of the Permit for MW-12 and MW-31 for the third quarter of 2020.
Part I.G.2 of the Permit provides that out-of-compliance status exists when the concentration of a
pollutant in two consecutive samples from a compliance monitoring point exceeds a groundwater
compliance limit ("GWCL") in Table 2 of the Permit. While consecutive exceedance have been
noted in other wells at the site, a P&TS and Source Assessment Report ("SAR") have not been
required or appropriate in light of other actions currently being undertaken by EFRI or in light of
other reports submitted by EFRI, and as determined by Division of Waste Management and
Radiation Control ("DWMRC") Staff. Specifically, consecutive exceedances, which occurred in
previous reporting periods are discussed in previous SARs submitted to DWMRC. Additionally,
pH was addressed in reports dated November 9, 2012 and December 7, 2012. A description of
the other actions and reports which have affected the requirement to submit a P&TS are as
follows:
1. Nitrate + nitrite and chloride in monitoring wells at the site have been the subject of
ongoing investigations at the Mill. Based on the results of the previous investigations,
EFRI and the Director acknowledge that it has not been possible to date to determine the
source(s), cause(s), attribution, magnitudes of contribution, and proportion(s) of the local
nitrate + nitrite and chloride in groundwater. EFRI submitted a Corrective Action Plan
("CAP") in February 2012 for nitrate + nitrite and chloride in groundwater. The CAP
was approved on December 12, 2012 and the activities associated with the CAP are on-
going. Based on information provided by DWMRC in teleconferences on April 27, and
May 2, 2011, due to the ongoing activities and actions, the 30-day plan and schedule for
assessment is not required for nitrate + nitrite and chloride exceedances at this time.
2. As discussed in previous quarterly groundwater sampling reports, the background levels
and GWCLs for pH were established based on eight or more quarters of laboratory data,
which are historically higher than field data. EFRI' s letter to the Director dated January
31, 2011 proposed the recalculation of the GWCLs for field pH. Following the statistical
evaluation of pH data by EFRI's geochemical consultant, INTERA, Inc., EFRI compared
the Mill's groundwater pH data from Q2 2011 and noted that all of the June 2011
groundwater results, and many of the other results from Q2 2011, were already outside
the revised GWCLs that were to be proposed in the June 30, 2011 letter. Pursuant to
teleconferences with DWMRC on December 5, and December 19, 2011, EFRI submitted
a Work Plan and Schedule on January 20, 2012 and a revised plan based on DWMRC
comments on April 13, 2012. Based on the approved Work Plan and Time Schedule,
EFRI and DWMRC entered into a Stipulated Consent Agreement ("SCA") dated July 12,
2012. The SCA required the completion of the pH Report and the Pyrite Investigation
and associated report. The pH Report and Pyrite Investigation Report were submitted
November 9, 2012 and December 7, 2012 respectively. By letter dated April 25, 2013,
DWMRC accepted the conclusions that the out-of-compliance results for pH are due to
background effects within the aquifer matrix and are not caused by Mill activities.
DWMRC also approved the recalculation of the GWCLs. As a result, the 30-day plan and
schedule for assessment is not required for field pH exceedances.
3. A P&TS will not be prepared for monitoring wells with two successive exceedances, if
those successive exceedances were reported in a previous quarter and /or were included
in a previous SAR during the current permit period beginning March 19, 2019, because
the conclusions and actions delineated in those reports were accepted by DWMRC.
Chloroform and methylene chloride are the subject of the ongoing chloroform pumping program
and are covered by State of Utah Notice of Violation ("NOV") and Groundwater Corrective
Action Order ("CAO") State of Utah Department of Environmental Quality ("UDEQ") Docket
No. UGW-20-01. As a result, the 30-day plan and schedule for assessment of chloroform and
methylene chloride exceedances is not required.
Groundwater at the Mill site has been evaluated in multiple recent investigations and reports,
including the Revised Background Groundwater Quality Report (1NTERA, 2007a) and the New
Wells Background Report (INTERA, 2008) (collectively with 1NTERA, 2007b, the "Background
Reports"), the pH Report (INTERA, 2012), an isotopic investigation (Hurst and Solomon, 2008), a
report discussing the occurrence and likely impact of naturally-occurring pyrite on perched
(shallow) groundwater (the Pyrite Report [HGC, 20124), and multiple SARs.
Based on a review of the Background Reports and other information and analyses the Director
re-opened the Permit and modified the GWCLs to be equal to the mean concentration plus two
standard deviations or the equivalent of background for each constituent on an intrawell basis.
The modified GWCLs became effective on January 20, 2010. A new GWDP was issued on
January 19, 2018. The January 19, 2018 GWDP incorporated the revised GWCLs that resulted
from previous SARs. A revised GWDP was issued on March 19, 2019. The revised GWDP
incorporated the revised GWCLs that resulted from previous SARs among other changes.
Part I.G.4 c) of the GWDP states, with respect to exceedances of GWCLs, "that the Permittee
shall prepare and submit within 30 calendar days to the Executive Secretary a P&TS for
assessment of the sources, extent and potential dispersion of the contamination, and an
evaluation of potential remedial action to restore and maintain groundwater quality to insure that
Permit limits will not be exceeded at the compliance monitoring point and that DMT or BAT
will be reestablished." Pursuant to this requirement, EFRI has previously submitted P&TSs and
SARs to address previous dual exceedances (as required in light of other actions currently being
undertaken by EFRI and as determined by DWMRC Staff and stated in teleconferences with
EFRI on April 27 and May 2, 2011).
This P&TS covers selenium and uranium in MW-12 and uranium in MW-31, identified as being
in violation of Part I.G.2 of the Permit, in the Third Quarter 2020 Exceedance Notice, dated
October 20, 2020.
2. CONSTITUENTS AND WELLS SUBJECT TO THIS PLAN
The following constituents are covered by this P&TS:
Table 1
Constituents and Wells Subject to this Plan
Constituent POC Well GWCL (R/L) Q2 and Q3 2020 Results (N/L)
Selenium MW-12 39 41.2, 40.1
Uranium MW-12 23.5 23.7, 25.6
Uranium MW-31 15 15.5, 18.1, 19.7, 18.5
It should be noted that the Third Quarter 2020 Exceedance Notice identifies a number of wells
with consecutive exceedances of other constituents that are not included in this P&TS, for the
reasons stated in Section 1 above and in the Third Quarter 2020 Exceedance Notice. This P&TS
is being submitted to DWMRC by EFRI to address exceedances in MW-12 for selenium and
uranium and exceedances in MW-31 for uranium. The uranium exceedances in MW-31 have
exceeded the GWCLs due to statistically significant trends noted in previous studies.
Nitrate + Nitrite and Chloride concentrations in MW-31 are associated with the Nitrate/Chloride
plume, and are currently covered by the December 12, 2012 Stipulation and Consent Order.
With respect to pH, EFRI and DWMRC entered into a Stipulated Consent Agreement ("SCA")
dated July 12, 2012. The SCA required the completion of the pH Report and the Pyrite
Investigation and associated report. The pH Report and Pyrite Investigation Report were
submitted November 9, 2012 and December 7, 2012 respectively. By letter dated April 25,
2013, DWMRC accepted the conclusions that the out-of-compliance results and site-wide
decrease in pH are due to background effects within the aquifer matrix and are not caused by
Mill activities. The site-wide decrease in pH due to background effects within the aquifer matrix
has continued.
3. CATEGORIES FOR ANALYSIS
EFRI has previously categorized wells and constituents in several categories as follows:
• Constituents Potentially Impacted by Decreasing pH Trends Across the Site
• Newly Installed Wells with Interim GWCLs
• Constituents in Wells with Previously Identified Rising Trends
• Pumping Wells
• Other Constituents
Selenium and uranium in MW-12 fall within the fifth category: Other Constituents. It is
important to note that selenium and uranium in MW-12 also fall within the first and third
category: Constituents Potentially Impacted by Decreasing pH Trends Across the Site and
Constituents in Wells with Previously Identified Rising Trends, respectively.
Uranium in MW-31 falls within the third category: Constituents in Wells with Previously
Identified Rising Trends. It is important to note that uranium in MW-31 also falls within the first
category: Constituents Potentially Impacted by Decreasing pH Trends Across the Site.
Assessment of these constituents in MW-12 and MW-31 will follow the process noted below.
3.1. Other Constituents
As previously noted selenium and uranium also fall within the third category and the fifth
category. Assessment of selenium and uranium in MW-12 will follow the process detailed
below.
MW-12 is west of MW-05 on the dike between Cell 3 and Cell 4B. When wells MW-05 and
MW-12 were installed the top of the casing ("TOC") for both wells was above the ground
surface by several feet. During the construction of the dike of Cell 4B several feet of fill dirt was
placed around MW-05 and MW-12. MW-05 and MW-12 were not extended and the TOC of
both MW-05 and MW-12 was slightly below the ground surface. MW-05 was extended in May
2017 in response to variable uranium concentrations likely caused by dust and dirt entering the
well during sampling activities.
Since MW-12 has reported exceedances of uranium similar to MW-05 and due to the proximity
of MW-12 to MW-05, prior to completing a Source Assessment Report ("SAR"), EFRI believes
it is appropriate to first address potential physical causes.
In an effort to address potential physical causes of the exceedances, EFRI made changes to the
casing and surrounding area in October 2020. The TOC for MW-12 was slightly below the
ground surface and may have inadvertently allowed dust and dirt to enter the well during
sampling activities. To address this issue EFRI extended the TOC several feet and regraded the
area surrounding the well. After the TOC was extended, the well was overpumped to remove
any dirt which may have been introduced during these field activities. These activities were
completed after the second quarter 2020 sampling event was conducted.
EFRI will continue accelerated monitoring as required by the GWDP and discuss any additional
findings in the groundwater reports. EFRI will monitor the accelerated results of selenium and
uranium in MW-12 for four quarters beginning with the fourth quarter 2020 through the third
quarter 2021. Progress and results will be discussed in the routine quarterly groundwater reports.
Future actions, if necessary, will be discussed in the third quarter 2021 groundwater report. If
the exceedances continue, a separate P&TS will be submitted for DWMRC approval.
3.2. Constituents in Wells with Previously Identified Rising Trends
Uranium concentrations in MW-31 exhibit a statistically significant upward trend first identified
during the 2015 SAR (INTERA, 2015). Uranium was also addressed in the 2017 SAR, and has
exceeded the revised GWCL due to statistically significant trends noted in these previous studies.
The most recent study of MW-31 was completed and submitted in June 2020 to address
exceedances of sulfate and total dissolved solids ("TDS") in MW-31.
The location of MW-31 is important when determining potential sources of contamination.
The previous SAR concluded that the increasing chloride concentration was due to the proximity
of that well to the nitrate/chloride plume. MW-31 is located in the southern edge of
nitrate/chloride plume. The nitrate/chloride plume has been the subject of many studies that are
described in detail in the following reports:
• Nitrate Contamination Investigation Report
• Quarterly Nitrate Reports 2009-2018
The nitrate/chloride plume is currently being addressed by the ongoing activities under the
DWMRC-approved CAP.
As previously stated, MW-31 was recently studied and assessed in June of 2020 (INTERA,
2020). The June 2020 SAR for MW-31 included the following analyses:
(i) A geochemical analysis;
(ii) A mass balance analysis;
(iii) An analysis of constituents influenced by the nitrate and/or chloride plume; and
(iv) An analysis of constituents influenced by changes in pH or any other natural
phenomenon.
The 2020 SAR concluded that a change in concentrations of parameters in MW-31 can be
observed after monthly monitoring started in 2010, after the well redevelopment effort in 2011,
after analytical changes in 2012, after the groundwater elevation peak in 2013, and after changes
to the chloroform CAP in 2014.
Significant increasing trends in MW-31 can be attributed to one or more of the following: (1)
natural background conditions; (2) pyrite oxidation in the aquifer, which can decrease pH,
increase mobility of metals, and increase sulfate and TDS concentrations; (3) the location of this
well within the nitrate/chloride plume, which is actively being remediated according to the CAP
(HGC, 2012b); and/or (4) effects of recent events on groundwater in MW-31 such as well
redevelopment, increased sampling frequency, changes in water levels, and analytical
method/laboratory change, as described in Section 3.1 of the 2015 SAR (INTERA, 2015).
The site-wide comparison of concentrations in MW-31 showed that even with significant
increasing long-term trends, many of the constituents are present in concentrations less than or
within the range of site-wide background concentrations. Thus, increasing concentrations in
MW-31 over time are likely due to the decreasing trend in pH across the Mill site and the
location of this well within the existing nitrate/chloride plume, and not to potential tailings
system seepage.
As stated above, this comprehensive assessment was completed in June 2020. Since the June
2020 assessment was completed, only a few data points have been collected and the 2020
assessment remains current with no changes required. The SAR for the uranium exceedance
noted herein, will rely on the geochemical, pH, indicator parameter and plume assessments
included in the June 2020 SAR. The SAR submitted in association with this P&TS will not
repeat or reproduce the June 2020 assessments and will only include the relevant statistics and a
recalculation of the GWCLs for uranium in MW-31.
4. PLAN
4.1. General
This is a P&TS for assessment of the sources, extent and potential dispersion of the
contamination, and an evaluation of potential remedial action to restore and maintain
groundwater quality to ensure that Permit limits will not be exceeded at the compliance
monitoring point and that, to the extent applicable, discharge minimization technology and best
available technology will be reestablished.
Given the recent analyses in the Background Reports, SARs, pH Report, and Pyrite Report and
other recent information relating to the Chloroform and Nitrate/Chloride investigations at the
site, EFRI believes that all of the exceedances are likely due to background influences (including
a natural decreasing trend in pH across the site, changing water levels in some wells and other
factors), disruption of the aquifer by pumping, and/or the geochemical influences of the existing
chloroform and nitrate/chloride plumes.
4.2 Other Constituents
Therefore, the analysis of the exceedances in MW-12 will be to continue monitoring on an
accelerated schedule (from semi-annually to quarterly) for selenium and uranium, as required by
the GWDP. As stated in Section 3.1 above, an assessment of the selenium and uranium results
will be completed after four quarters of data are collected (fourth quarter 2020 through third
quarter 2021). If the selenium and uranium results continue to exceed the GWCL, EFRI will
proceed with a P&TS under separate cover at that time.
4.2. Constituents in Wells with Previously Identified Rising Trends
The primary focus of a source assessment for uranium in MW-31 is to determine whether or not
there is any new information that would suggest that the previous analysis conducted in the New
Wells Background Report, SARs, pH Report and Pyrite Report has changed since the date of
those Reports. This assessment has been recently completed in June of 2020. In light of the
conclusions and the lack of contradictory data, this assessment is considered complete. A
abbreviated SAR will be completed for uranium in MW-31.
Since no significant changes were identified that would suggest that the previous analyses
conducted in the June 2020 SAR has changed, EFRI will propose changes to the GWCL to better
reflect current conditions at the site.
4.2.1 Expert Reports to be Prepared
The results of the statistical analysis and recalculation of the GWCL will be compiled as an
abbreviated SAR that will be submitted to DWMRC within 90 days of the approval of this plan.
The SAR will detail the results of the statistical analyses performed and the proposed revisions to
the existing GWCL. Specifically, the SAR will follow the format of the previously submitted
SARs, including much of the analysis performed in previous MW-31 SARs by reference with
updated sections applicable to the GWCL analyses as noted below:
A statistical analysis of uranium in MW-31
Descriptive statistics
Box plots to identify extreme outliers
Histograms and Shapiro Wilk test for normality
Regression or Mann Kendall trend analysis
Proposed Revised GWCLs for Uranium in MW-31
5. TIME SCHEDULE
The SAR for MW-31 will be submitted to the Director within 90 days after approval of this
P&TS. The SAR contemplated by this submission may be combined with any subsequent SARs
resulting from other P&TSs for other out of compliance constituents, as necessary.
6. CONCLUSION
Given the varied background groundwater quality at the site it cannot be assumed that
consecutive exceedances of a constituent in a monitoring well means that contamination has
been introduced to groundwater in that well.
The information from historical exceedances at MW-05 and current exceedances in MW-12 are
indicative of a potential physical component contributing to the exceedances. The physical
issues have been addressed and will be assessed. Further actions will be based on the results of
the accelerated monitoring described above.
The location of MW-31 is important when determining potential sources of contamination.
MW-31 was included in previous SARs, the most recent being completed in June 2020. The
previous SARs concluded that the concentrations of many constituents in MW-31 were due to or
affected by the sitewide oxidation of pyrite and the proximity of that well to the nitrate/chloride
plume. MW-31 is located at the margin of the nitrate/chloride plume. The nitrate/chloride plume
has been the subject of many studies that are described in detail in separate reports.