DRC-2020-010571 - 0901a06880c958f0

Energy Fuels Resources (USA) Inc.
225 Union Blvd. Suite 600
Lakewood, CO, US, 80228
303 974 2140
www. energyfuel s. com Di3C-2.020-ol 057 1
May 21, 2020
Sent VIA E-MAIL AND EXPRESS DELIVERY
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
Div of Waste Management
and Radiation Control
MAY 2 7 2020
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-28 for the first
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 MW-28 and 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-28 that was identified as being in violation of Part I.G.2 of the
Permit, in the First Quarter 2020 Exceedance Notice, dated April 30, 2020. It is important to note that uranium
has had dual exceedances reported prior to the first quarter of 2020 and was the subject of a P&TS dated
December 4, 2014. Details regarding the December 4, 2014 Plan are included in Section 1.1 of the attached
Plan.
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
Paul Goranson Logan Shumway
Terry Slade
Angie Persico (Intera)
Stewart Smith (HGC)
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-28 in the First Quarter of 2020
Energy Fuels Resources (USA) Inc.
225 Union Boulevard, Suite 600
Lakewood, CO 80228
May 21, 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 (the "Plan") required under Part I.G.4(c) of the Permit relating
to violations of Part I.G.2 of the Permit for the MW-28 for the first 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 MW-
28 and other wells at the site, a plan and time schedule 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 plan and time schedule 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
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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 Plan and Time Schedule 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, 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.
The Permit was originally issued in March 2005, at which time GWCLs were set on an interim
basis, based on fractions of State Ground Water Quality Standards or the equivalent, without
reference to natural background at the Mill site. The Permit also required that EFRI prepare a
background groundwater quality report to evaluate all historic data for the purposes of establishing
background groundwater quality at the site and developing GWCLs under the Permit.
As required by then Part I.H.3 of the Permit, EFRI submitted the following to the Director of the
State of Utah Division of Radiation Control (the "Director"):
• 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"); and
• 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 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.
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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 plan and a time schedule
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 Plans and Time
Schedules 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 Plan covers selenium and uranium in MW-28 that was identified as being in violation of Part
I.G.2 of the Permit, in the First Quarter 2020 Exceedance Notice, dated April 30, 2020. It is
important to note that uranium has had dual exceedances reported prior to the first quarter of 2020
and was the subject of a P&TS dated December 4, 2014. The December 4, 2014 P&TS was
submitted after dual exceedances of uranium, cadmium and vanadium that were reported after
physical damage to the well and casing in May 2014. Details of the December 4, 2014 P&TS are
included in Section 1.1 below.
1.1. Previous P&TS
On May 28, 2014, EFRI notified DWMRC personnel of damage to Monitoring Well 28 ("MW-
28"). The damage was noted by EFRI Environmental Staff during routine, quarterly sampling
activities. Upon arrival at MW-28, EFRI Environmental Staff noticed that there was evidence that
a vehicle had struck the outer protective metal casing of MW-28 and it was slightly bent and
leaning to the west. Inspection of the inner, 10-inch PVC protective casing and the 4-inch well
casing also showed signs of damage. The concrete seal between the 10-inch outer casing and the
4-inch casing was cracked and EFRI Environmental Staff noted that the inner PVC casing was
likely cracked and/or broken. Upon discovery of the damage on May 28, 2014, EFRI
Environmental Staff contacted the EFRI QAM. The EFRI QAM notified DWMRC in person,
while at the DWMRC offices in Salt Lake City. On June 2, and June 5, 2014 Environmental Staff
and Bayles Exploration repaired the well and removed the debris in the bottom of the well resulting
from the damage. The Environmental Staff then over pumped the well and removed over 4 casing
volumes to redevelop the well. The well was sampled and the routine, second quarter 2014 sample
was collected on June 18, 2014.
Three new analytes were reported above the GWCL in the second quarter 2014 data. The analytes
are uranium, vanadium and cadmium. Per the GWDP, EFRI began accelerated monitoring in third
quarter 2014 at MW-28 for those three constituents. The fourth quarter 2014 MW-28 results for
vanadium and cadmium were below the GWCLs. The uranium result remained above the GWCL
in the third quarter 2014. Part I.G.4 c) of the GWDP requires a Plan and Time Schedule for
constituents exceeding their GWCL in two consecutive monitoring periods. The Plan and Time
Schedule specified that an assessment of the uranium results would be completed after the first
quarter 2015 sampling event. If the uranium results continue to exceed the GWCL, EFRI would
perform a video inspection of the interior of MW-28 to investigate the possibility of additional
physical damage to the well structure that may be causing the elevated uranium results. The
uranium results fluctuated above and below the GWCL in MW-28 between 2014 and 2018.
Beginning in 2019, the uranium results have been consistently above the GWCL.
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2. CONSTITUENTS AND WELLS SUBJECT TO THIS PLAN
The following constituents are covered by this Plan:
Table 1
Constituent and Well Subject to this Plan
Constituent POC Well GWCL Q4 2019 and
Q1 2020
Results
Uranium
(ug/L) MW-28 4.9 12.4, 7.56
Selenium
(ug/L) MW-28 11.1 16.5, 13.4
It should be noted that the First Quarter 2020 Exceedance Notice identifies a number of wells, with
consecutive exceedances of other constituents. None of those constituents are included in this
Plan, for the reasons stated in Section 1 above and in the First Quarter 2020 Exceedance Notice.
This Plan and the associated SAR are being submitted to DWMRC by EFRI to address
exceedances in MW-28 for selenium and uranium which have exceeded the GWCLs. Chloride and
nitrate concentrations in MW-28 are associated with the Nitrate/Chloride plume, and are currently
covered by the December 12, 2012 Stipulation and Consent Order.
3. CATEGORIES FOR ANALYSIS
Previously EFRI has 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 can fall within the first category when downward pH trends are noted,
however pH in MW-28 is near-circumneutral and does not exhibit a decreasing trend. In the case
of MW-28, selenium and uranium fall into the fifth category: Other Constituents. Assessment of
these constituents in MW-28 will follow the process noted below with additional considerations
to address the fact that MW-28 is within the boundaries of the chloride plume. Additionally, the
current GWCLs for selenium and uranium were calculated at the time of the New Wells
Background Report using 11 data points. The natural variability of groundwater chemistry across
the site is well documented and that variability is expected to increase within the proximity of the
chloride plume.
3.1. Other Constituents
The assessment for this SAR will follow the process previously used for constituents classified
under the "other" category.
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The location of MW-28 is important when determining potential sources of contamination.
Previous SARs concluded that the increasing concentrations of various analytes in wells located
within the nitrate/chloride plume were due to the proximity of the wells to the plume. MW-28 is
located within the leading edge of the chloride plume and is generally downgradient of the
historical pond, the likely source of the commingled nitrate and chloride plumes (collectively the
N/C1 plume). Chloride at MW-28 has been generally increasing at least since 2009 ; nitrate is
lagging chloride due to degradation, by pyrite, and has not reached MW-28 at concentrations
exceeding 10 mg/L. However, nitrate began increasing in late 2014, reaching 5 mg/L in late 2019.
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 2009-2020
The nitrate/chloride plume is currently being addressed by the ongoing activities under the
DWMRC-approved CAP.
Other factors to consider in the evaluation of MW-28 include the following:
1) Concentration of indicator parameters fluoride and sulfate are decreasing and stable,
respectively.
2) Background conditions in MW-28 were last evaluated at the time of the New Wells Background
Report. GWCLs for MW-28 were calculated using only 11 data points, therefore the GWCLs may
not represent the natural variability and/or current conditions of groundwater at the site.
3) The increase in nitrate since late 2014 correlates to increases in selenium and uranium
concentrations exceeding the GWCL. The selenium may result from nitrate oxidizing and
mobilizing naturally-occurring selenium; or selenium that may be generally elevated in the
nitrate/chloride plume due to the historical pond having seeped through the Mancos Shale (a source
of selenium) is now migrating past MW-28; or selenium may be released from pyrite oxidized by
nitrate or from elevated dissolved oxygen (DO) in the plume.
4) The recent elevated concentrations of calcium and bicarbonate are consistent with mobilization
of naturally-occurring uranium in the formation. There is also evidence in the literature of an
association between increased nitrate and increased uranium. The association between elevated
uranium and nitrate has been documented in many aquifers.
4. PLAN
4.1. General
This Plan is a plan and time schedule 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
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point and that, to the extent applicable, discharge minimization technology and best available
technology will be reestablished.
Given the recent site-wide 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 exceedances in MW-28 are likely due to background influences
(including 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.
Therefore, the first step in the analysis will be 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 due to background influences then it will not be
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 will be proposed to reflect changes in background
conditions at the site.
However, if any of the exceedances are determined to be caused by Mill activities, then EFRI will
proceed to the next step and will consider the extent and potential dispersion of the contamination,
and will perform an evaluation of potential remedial actions to restore and maintain groundwater
quality to ensure that Permit limits will not be exceeded at the compliance monitoring point.
This two-step approach is necessary, because, in light of the varied background conditions at the
site, it can't be assumed that consecutive exceedances of a constituent in a well represents
contamination that has been introduced to the groundwater. It is first necessary to establish
whether or not the exceedances represent background influences.
4.2. Other Constituents
The primary focus of the source assessment for these constituents will again be to determine
whether or not there is any new information that would suggest that the previous analysis
conducted in the New Wells Background Report, or other site-wide evaluations such as SARs, the
pH Report, and the Pyrite Report has changed since the date of those Reports. This analysis will
include the following for each constituent listed in Table 1:
(i) A geochemical analysis that will evaluate the behavior of constituents in MW-28 to
determine if there are any changes in the behavior of indicator constituents, such as
chloride, sulfate, fluoride and uranium since the date of the New Wells Background
Report that may suggest a change in the behavior of that well since the date of that Report;
(ii) If necessary, a mass balance analysis that will evaluate the observed concentrations in
light of the concentrations in Mill tailings and the presence or absence of any mounding
at the location of the well in question;
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(iii) An analysis of the extent, if any, to which the constituents may be influenced by
geochemical changes caused by migrating nitrate and/or chloride or chloroform from the
existing plumes; and
(iv) An analysis of the extent, if any, to which the constituents may be influenced by changes
in other constituents in ground water that have resulted from changes in pH or any other
natural phenomenon.
The foregoing analysis will be included in the SAR.
If no significant changes are identified that would suggest that the previous analyses conducted in
the Background Reports for the constituents in question has changed, then EFRI will propose
changes to the GWCLs for those wells to better reflect background concentrations at the site.
If significant changes are identified that are attributable to geochemical changes caused by either
the nitrate/chloride plume or the chloroform plume, then the constituents should be considered in
connection with the applicable plume, and the associated CAP.
If significant changes are identified that cannot be attributed to one of the existing plumes, or other
background influences, then EFRI will propose to the Executive Secretary further analysis that
may be required in order to identify the source and the extent and potential dispersion of the
contamination, as well as potential remedial actions.
4.3. Expert Reports to be Prepared
The results of the statistical analysis and, if appropriate, recalculation of the GWCLs will be
compiled as a SAR that will be submitted to DWMRC within 90 days of the approval of this plan.
The SAR will detail the results of all of the analyses performed and the conclusions drawn from
such analyses, including any proposed revisions to existing GWCLs. Specifically, the SAR will
follow the format of the previously submitted SARs and will include discussions, results and
conclusions of the analyses and appendices containing the following:
A statistical analysis of SAR parameters in MW-28 to support a geochemical evaluation
Comparison of calculated and measured TDS for samples with complete major ions
Charge balance calculations
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 MW-28
A statistical analysis of Indicator Parameters in MW-28
Descriptive Statistics
Box plots to identify extreme outliers
Histograms and Shapiro Wilk test for normality
Regression and/or Mann Kendall trend analysis
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5. TIME SCHEDULE
The SAR will be submitted to the Director within 90 days after approval of this Plan. The SAR
contemplated by this submission may be combined with any subsequent SARs resulting from other
Plans and Schedules 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 location of MW-28 is important when determining potential sources of contamination.
The concentrations of many constituents in MW-28 were due to or affected by the proximity of
that well to the nitrate/chloride plume. MW-28 is located within the leading edge of the chloride
plume and is generally downgradient of the historical pond, the likely source of the commingled
nitrate and chloride plumes (collectively the N/C1 plume). Chloride at MW-28 has been generally
increasing at least since 2009; nitrate is lagging chloride due to degradation, by pyrite, and has not
reached MW-28 at concentrations exceeding 10 mg/L. However, nitrate began increasing in late
2014 reaching 5 mg/L in late 2019. The nitrate/chloride plume has been the subject of many
studies that are described in detail in separate reports. Additionally, conditions in MW-28 have not
been evaluated since the time of the New Wells Background Report. Current GWCLs were
calculated using only 11 data points, therefore the GWCLs may not reflect the natural variability
and current conditions of groundwater at the site.
Concentration of indicator parameters fluoride and sulfate are decreasing and stable, respectively.
The increase in nitrate since late 2014 correlates to increases in selenium and uranium. Nitrate may
be oxidizing and mobilizing naturally-occurring selenium; or selenium that may be generally
elevated in the nitrate/chloride plume due to the historical pond having seeped through the Mancos
Shale is now migrating past MW-28; or selenium may be released from pyrite oxidized by nitrate
or from elevated dissolved oxygen (DO) in the plume.
The presence of calcium and bicarbonate are consistent with mobilization of naturally-occurring
uranium in the formation. There is also evidence in the literature of an association between
increased nitrate and increased uranium. The association between elevated uranium and nitrate has
been documented in many aquifers.
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