DRC-2023-077464 - 0901a068812c4d81

DRC-2023-077464 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. 711 www.deq.utah.gov Printed on 100% recycled paper
State of Utah
SPENCER J. COX Governor DEIDRE HENDERSON Lieutenant Governor
Department of Environmental Quality
Kimberley D. Shelley Executive Director DIVISION OF WASTE MANAGEMENT AND RADIATION CONTROL Douglas J. Hansen Director December 5, 2023

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 15, 2023, Transmittal of Plan and Time Schedule under Utah Groundwater Discharge Permit No. UGW370004 (Permit)

Dear Ms. Weinel: The Division of Waste Management and Radiation Control (Division) has reviewed the Energy Fuels Resources (USA) Inc. (EFRI) November 15, 2023, Transmittal of Plan and Time Schedule under Utah
Groundwater Discharge Permit UGW370004 Part I.G.4(c) White Mesa Mill (EFRI Plan). The EFRI
Plan addresses dual exceedances of the Groundwater Compliance Limit (GWCL) for selenium in monitoring well MW-03A. Selenium in MW-03A is in out-of-compliance status per the Permit Part I.G.2. based on the EFRI 3rd Quarter 2023 Exceedance Notice dated October 25, 2023, and are therefore required to undergo corrective action per the Permit Part I.G.4.

The table below summarizes the preliminary findings in the EFRI Plan:
Monitoring Well Parameters EFRI Noted Preliminary Findings and Source Assessment
MW-03A Selenium
• EFRI notes that concentrations of indicator parameters chloride and sulfate in MW-03A are stable.
• EFRI notes that concentrations of indicator parameters fluoride and uranium in MW-03A are decreasing.
• The EFRI Plan states that the selenium exceedance in MW-03A is likely due to natural background influences that impact the groundwater geochemistry near MW-03A.
• EFRI notes that possible natural background influences
include changing water levels and enhanced oxygen transport to groundwater through the well casing.

Monitoring Well Parameters EFRI Noted Preliminary Findings and Source Assessment
• EFRI notes that background influences are also consistent with recent site-wide analyses performed for Background
Reports, previous source assessment reports (SARs), and
the Pyrite Report.
• Per the EFRI Plan, the new SAR will include a source investigation and statistical analysis that will evaluate the behavior of selenium and indicator parameters in MW-03A
to determine if there are any changes since the date of the Background Reports.
• EFRI plans to demonstrate that “increasing selenium cannot result from potential TMS seepage and it is unlikely
that analysis will reveal the need for any further evaluation
of the extent and potential dispersion of any contamination or for an evaluation of potential remedial actions.”
• EFRI anticipates continued monitoring and proposal of
revised GWCLs to reflect changes in background
conditions at the site.

A SAR which will include a source investigation and statistical analysis, per the EFRI Plan Section 4,
will be submitted to the Director of the Division of Waste Management and Radiation Control within 90 days after approval of the EFRI Plan. Based on review of the EFRI Plan, it appears that the proposed activities are appropriate, and the
EFRI Plan is hereby approved.
If you have any questions, please call Chris Leahy at 385-602-5505. Sincerely,

Phil Goble, Uranium Mills and Radioactive Materials Manager Division of Waste Management and Radiation Control
PRG/CL/jk c: Grant Sunada, Executive Director/Health Officer, San Juan County Public Health Department
Ronnie Nieves, Environmental Health Director, San Juan County Public Health Department Russell Seeley, District Engineer, UDEQ