DRC-2025-001971

299 South Main Street, Suite 1700 ▪ Salt Lake City, Utah 84111
[phone] ▪ Fax: [phone] ▪ www.energysolutions.com
June 10, 2025 CD-2025-122
Mr. Doug Hansen, Director
Division of Waste Management and Radiation Control
P.O. Box 144880
Salt Lake City, UT 84114-4880
Subject: Groundwater Quality Discharge Permit Number UGW450005 (GWQDP):
Notification of Return of Monitoring Wells GW-29, GW-93, GW-100 and GW-127
to Quarterly Water Level Measurement Frequency
Dear Mr. Hansen:
EnergySolutions is providing notice that the frequency of water-level monitoring at wells
GW-29, GW-93, GW-100, and GW-127 has returned to quarterly monitoring, in accordance
with the modification to GWQDP Part I.F.5.a, approved by the Director of the Division of
Waste Management and Radiation Control on March 28, 2023 (DRC-2023-001933).
•On March 10, 2023, EnergySolutions notified that monitoring frequency for wells
GW-29 and GW-93 was changed from quarterly to monthly (Submittal
CD-2023-059).
•On June 28, 2023, monitoring at GW-100 was changed to monthly (Submittal
CD-2023-130).
•On January 16, 2025, monitoring at GW-127 was changed to monthly (SubmittalCD-2025-011).
Subsequent depth-to-water measurements have demonstrated stabilization of groundwater
levels. As of May 2025, the depth-to-water measurements are as follows, each within or
below the 0.4-foot criterion specified in Part I.F.5.a:
•GW-29: 0.39 feet from baseline
•GW-93: 0.37 feet from baseline
•GW-100: 0.40 feet from baseline
•GW-127: 0.07 feet from baseline
Mr. Doug Hansen
June 10, 2025
CD-2025-122
Page 2 of 2
In accordance with GWQDP Part I.H.2, this information will be documented in the Annual
Monitoring Report to be submitted by March 1, 2026.
If you have any questions regarding this notification, please contact me at [phone].
Sincerely,
Mathew R Schon
Manager, Groundwater and Environmental Program
I certify under penalty of law that this document and all attachments were prepared under my direction or supervision in accordance
with a system designed to assure that qualified personnel properly gather and evaluate the information submitted. Based on my inquiry
of the person or persons who manage the system, or those persons directly responsible for gathering the information, the information
submitted is, to the best of my knowledge and belief, true, accurate, and complete. I am aware that there are significant penalties for
submitting false information, including the possibility of fine and imprisonment for knowing violations.