ML25006A089
| ML25006A089 | |
| Person / Time | |
|---|---|
| Site: | WM-00058 |
| Issue date: | 01/07/2025 |
| From: | Hayes K NRC/NMSS/DDUWP/URMDB |
| To: | Tallbull J US Dept of Energy, Office of Legacy Management |
| References | |
| Download: ML25006A089 (1) | |
Text
Joni R. Tallbull, Site Manager U.S. Department of Energy Office of Legacy Management 2597 Legacy Way Grand Junction, CO 81503
SUBJECT:
U.S. Nuclear Regulatory Commission Staff Review of U.S. Department of Energy, Office of Legacy Management, Annual Performance Report, April 2021 Through March 2022 for the Shiprock, New Mexico, Disposal Site (Docket WM-00058)
Dear Ms. Tallbull:
The U.S. Nuclear Regulatory Commissions (NRCs) staff is writing in response to the U.S.
Department of Energy, Office of Legacy Management (DOE-LM) submittal entitled, Annual Performance Report, April 2021 Through March 2022 for the Shiprock, New Mexico, Disposal Site, dated August 2023 (Received September 18, 2023; Agencywide Documents Access and Management System, Accession No. ML23261B476). NRCs comments on the submittal are listed below:
Section 3.2.1, Spatial Distribution and Concentration Trends, states that the highest concentrations of uranium in floodplain alluvium (0.8 - 0.9 mg/L) currently occur along the base of the escarpment just north of the disposal cell and in a zone traversing the floodplain in a line trending northward from the disposal cell. A review of the baseline and current uranium floodplain plumes in Figure 15 and the uranium concentration trends in the floodplain wells from 2006 to 2022 indicates increasing concentrations in central group wells 0857 and 1136, located near the San Juan River. The two wells exhibited some of the highest uranium concentrations observed in the 2022 floodplain well sampling, with concentrations of 0.84 and 0.83 mg/L reported for the 0857 and 1136 wells, respectively.
The wells are located approximately 500 to 800 feet to the southeast of the 1089/1104 extraction well locations. Gaps of several hundred feet in the floodplain monitoring well network in the areas surrounding both wells limit the ability to accurately determine concentration gradients in these areas, as well as determining the influence of the 1089/1104 extraction wells on the 0857 and 1136 monitoring wells. Additional monitoring well locations in the area and possibly additional extraction wells in closer proximity to the 0857 and 1136 wells may warrant consideration.
January 7, 2025
J. Tallbull 2
If you have any questions concerning this review, please contact me at 301-415-0549 or by email at Kevin.Hayes@nrc.gov.
Sincerely, Kevin R. Hayes, P.G., CPG, Hydrogeologist Uranium Recovery and Materials Decommissioning Branch Division of Decommissioning, Uranium Recovery, and Waste Programs Office of Nuclear Material Safety and Safeguards Docket Numbers: WM-00058 cc: Shiprock ListServ Signed by Hayes, Kevin on 01/07/25
ML25006A089; Ltr ML25006A089 OFFICE NMSS/DUWP
/URMDB NMSS/DUWP
/URMDB NMSS/DUWP
/URMDB NAME KHayes RVonTill KHayes DATE Jan 6, 2025 Jan 7, 2025 Jan 7, 2025