DRC-2022-021449 - 0901a068810f5bfd

September 21, 2022
Sent VIA EXPEDITED DELIVERY
Ms. Doug Hansen Director Division of Waste Management and Radiation Control
Utah Department of Environmental Quality
195 North 1950 West Salt Lake City, UT 84116
Energy Fuels Resources (USA) Inc. 225 Union Blvd. Suite 600 Lakewood, CO, US, 80228 303 974 2140
www .energyfuels.com
Re: Monitor Well MW-41 Reinstallation Proposal White Mesa Uranium Mill
Dear Mr. Hansen:
Pursuant to the teleconference with the Division of Waste Management and Radiation Control
("DWMRC") staff on August 18, 2022, Energy Fuels Resources (USA) Inc. ("EFRI") is submitting this
proposal for reworking and reinstallation of newly installed monitoring well MW-41 at the White Mesa Mill (the "Mill").
BACKGROUND
During discussions with DWMRC regarding the MW-24A Phase 2 investigation design, DWMRC requested the installation of another groundwater monitoring well down gradient of MW-24/MW-24A. The new well, MW-41, was installed down gradient from MW-24/MW-24A (in closer proximity to MW-24 than MW-2) on July 20, 2022. Pursuant to discussions with DWMRC and the DWMRC February 2, 2022 letter which stated, "The additional monitoring well should be constructed to eliminate suspected problems with well construction at MW-24/MW-24A (e.g. eliminate open well screen above the water
table)", EFRI planned to complete MW-41 using a shorter well screen to eliminate open well screen
above the water table (i.e. submerged screened interval).
The primary purpose of eliminating open screen above the water table is to minimize transport of air into the vadose zone in the vicinity of the well to in turn minimize oxygen transport to groundwater. As
previously discussed, enhanced oxygen transport to groundwater near monitoring wells increases pyrite
oxidation, lowers pH, and mobilizes trace metals contained in pyrite as well as pH sensitive metals that occur naturally in the formation hosting perched groundwater.
MW-41 drilling commenced on July 20, 2022, with EFRI collecting core during drilling. Water was
encountered at 92 feet during the drilling. In an effort to eliminate open well screen above the water
table, EFRI's geologist instructed the driller to screen the well from 100 feet to 130 feet (the total depth of the well).
Subsequent field activities conducted at the well included development using surge and bailing and
overpumping, and hydraulic testing. During field activities, the static water level was noted to be at
DRC-2022-021449
Letter to Mr. Doug Hansen
September 21, 2022
Page 3
EFRI will contact the driller after approval of this proposal either as written or as modified based on comments from DWMRC. EFRI will provide DWMRC 14-days notice prior to the start of field activities.
If you should have any questions regarding this submittal, please contact me.
Yours very truly,
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ENERGY FUELS RESOURCES (USA) INC.
Kathy Weinel Director, Regulatory Compliance
CC: David Frydenlund
Logan Shumway
Scott Bakken Garrin Palmer