DRC-2021-001122 - 0901a06880de8369

DRC-2021-001122 195 North 1950 West • Salt Lake City, UT Mailing Address: P.O. Box 144880 • Salt Lake City, UT 84114-4880 Telephone [phone] • Fax [phone] • T.D.D. [phone]
www.deq.utah.gov
Printed on 100% recycled paper
State of Utah
SPENCER J. COX Governor DEIDRE HENDERSON Lieutenant Governor
Department of Environmental Quality
Kimberly D. Shelley Interim Executive Director DIVISION OF WASTE MANAGEMENT AND RADIATION CONTROL Ty L. Howard Director
February 1, 2021
Kathy Weinel, Quality Assurance Manager
Energy Fuels Resources (USA) Inc.
225 Union Blvd., Suite 600 Lakewood, CO 80228 RE: Energy Fuels Resources (USA) Inc. November 18, 2020, Transmittal of Plan and Time Schedule, Groundwater Discharge Permit No. UGW370004 (Permit)
Dear Ms. Weinel: The Division of Waste Management and Radiation Control (DWMRC) has reviewed the Energy Fuels
Resources (EFR) November 18, 2020 Transmittal of Plan and Time Schedule under Utah Ground Water
Discharge Permit UGW370004 Part I.G.4(c) White Mesa Mill (EFR Plan). The EFR Plan addresses exceedances of the Ground Water Compliance Limits (GWCLs) for selenium and uranium in monitoring well MW-12 and uranium in monitoring well MW-31. These monitoring wells/constituents were identified to be in out-of-compliance status per the 3rd Quarter 2020 EFR Exceedance Notice, dated October 20, 2020, and are therefore required to undergo evaluation of corrective actions per the Permit
Part I.G.4. The table below summarizes the preliminary findings in the EFR Plan:
Monitoring Well Parameters EFR Noted Preliminary Findings
MW-12 Uranium
Selenium
• MW-12 Selenium and Uranium had dual exceedances of the GWCL (39 µg/L) during Q2 and Q3 2020.
• MW-12 well installation was affected by the emplacement
of fill material around the top of the casing during the construction of tailings cell 4B. As a result, the top of casing for MW-12 was slightly below ground surface.
• The casing for well MW-5 which showed similar problems
as MW-12 was extended in May 2017 in response to variable uranium concentrations likely caused by surface contamination during sampling due to the top of casing

Monitoring Well Parameters EFR Noted Preliminary Findings
issue. The changes appear to have addressed the variable uranium concentrations in MW-5.
• EFR extended the tip of casing for MW-12 during October 2020 in response to the uranium and selenium
concentrations per findings and discussions with DWMRC.
• EFR proposes to continue accelerated monitoring in MW-12 through the 3rd Quarter 2021 to determine if the well casing extension addresses the selenium and uranium exceedances.
MW-31 Uranium
• MW-31 Uranium exceeded the GWCL (15 µg/L) four consecutive times during Q2 and Q3 2020.
• Plan and Time Schedule notes a statistically significant rising trend for Uranium in MW-31. The trend was identified during a 2015 EFR Source Assessment Report
for MW-31.
• Several Source Assessment Reports have been submitted for MW-31, the most recent was submitted in June 2020 to address exceedances of sulfate and total dissolved solids.
• Nitrate/Nitrite and Chloride concentrations in MW-31 are associated with the Nitrate/Chloride plume and are regulated through the Corrective Action Plan Stipulation and Consent Order.
• Uranium concentrations in MW-31 are within the range of
site-wide background concentrations.
• Additional study of Uranium in MW-31 will rely on source assessment findings of the June 2020 SAR. The proposed
current MW-31 SAR will only included newer data since
the submission of that SAR and relevant statistics and recalculation of GWCL’s for Uranium,

Per review it is appropriate to continue accelerated monitoring at MW-12 to determine whether the modifications to the well, extended casing, will address the compliance issues for uranium and selenium. Per the EFR plan, the continued monitoring results will be discussed in quarterly monitoring reports and, if after continued monitoring it is determined that additional actions are warranted then EFR will
propose such actions in the 3rd Quarter 2021 Groundwater Monitoring Report and submit a separate Plan and Time Schedule for DWMRC for review and approval. Based on DWMRC review of the EFR Plan and telephone discussion with EFR, these actions appear to be appropriate. Therefore, a separate Source Assessment Report for uranium and selenium in MW-12 is not required at this time.

Per the EFR Plan, a Source Assessment Report for Uranium in MW-31 will not include detailed source
assessment since that was recently completed for a June 2020 MW-31 SAR. The SAR will include updated data analysis, statistics and proposed revised GWCL’s for uranium in MW-31. Per the EFR Report, the MW-31 SAR will be submitted to the Director within 90 days after approval of the EFR Plan (EFR Plan Section 5).

Based on review of the EFR Plan it appears that the planned activities for MW-12 and MW-31 are
appropriate, therefore the EFR Plan is hereby approved. If you have any questions, please call Tom Rushing at [phone]. Sincerely,
Phil Goble, Uranium Mills and Radioactive Materials Manager
Division of Waste Management and Radiation Control
PRG/TR/as
c: Ronnie Nieves, Environmental Director, San Juan Public Health Department
Russell Seeley, UDEQ District Engineer