DRC-2021-013942 - 0901a06880f610b5

DRC-2021-013942 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
Kimberley D. Shelley Executive Director
DIVISION OF WASTE MANAGEMENT AND RADIATION CONTROL Douglas J. Hansen Director September 29, 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. August 25, 2021, Transmittal of Plan and Time Schedule Groundwater Discharge Permit No. UGW370004 (Permit)
Dear Ms. Weinel: The Division of Waste Management and Radiation Control has reviewed the Energy Fuels Resources (USA) Inc. (EFRI) August 25, 2021, Transmittal of Plan and Time Schedule under Utah Ground Water
Discharge Permit UGW370004 Part I.G.4(c) White Mesa Mill (EFRI Plan).
The EFRI Plan addresses dual exceedances of the Ground Water Compliance Limits (GWCLs) for uranium and selenium in Monitoring Well MW-30. Monitoring Well MW-30 is in out-of-compliance status for uranium and selenium per the Permit Part I.G.2. based on the EFRI 2nd Quarter 2021 Exceedance Notice dated July 28, 2021, and is therefore required to undergo corrective action per the
Permit Part I.G.4. The following table summarizes the preliminary findings in the EFRI Plan:
Monitoring Well Parameters EFRI Noted Preliminary Findings and Source Assessment
MW-30 Uranium Selenium
• MW-30 is located within the downgradient (southern) margin of the nitrate chloride plume.
• EFRI notes that constituents in MW-30 exhibited upward
concentration trends first identified during the 2012 SAR and pH Report.
• EFRI preliminary analysis of indicator parameters in MW-30 shows that fluoride and sulfate are stable to decreasing.
• Although nitrate at MW-30 has been relatively stable since 2021, nitrate has increased since installation in 2005 which correlates to the increases in selenium and uranium. (Over)

Monitoring Well Parameters EFRI Noted Preliminary Findings and Source Assessment
The Plan hypothesizes that nitrate may be oxidizing and mobilizing naturally occurring uranium and selenium or that uranium and selenium may be generally elevated in the nitrate/chloride plume.
• The EFRI Plan generally discusses elements of a source
assessment study and source assessment report (SAR) which will be prepared to evaluate the uranium and selenium exceedances in MW-30. The Division notes that a submitted SAR must show through evidence and
evaluation that the Mill is not the source of the exceedances
and must conform to signatory requirements of the Permit. Although an evaluation of potential natural sources of the exceedances is informational and provides a potential
mechanism for the observed concentrations, the SAR must
show that the Mill is not the potential source.

An SAR, which will include the EFRI Plan discussed source investigation and statistical analysis, will
be submitted to the Division Director within 90 days after approval of the EFRI Plan. The Division again notes that the conclusions of the SAR must definitively eliminate or support a Mill source of the observed exceedances. Based on review of the EFRI Plan it appears that the planned activities are appropriate, and the EFRI
Plan is hereby approved with Division comments as noted above. 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: Mike Moulton, Interim Health Officer, San Juan County Public Health Department
Ronnie Nieves, Environmental Health Director, San Juan County Public Health Department Russell Seeley, UDEQ District Engineer