ML25002A232
| ML25002A232 | |
| 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: ML25002A232 (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, Shiprock, New Mexico, Disposal Site, Water Treatment Unit Infrastructure Project 90% Design Review (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, Shiprock, New Mexico, Disposal Site, Water Treatment Unit Infrastructure Project, 90% Design Review, dated December 3, 2024 (Received December 3, 2024; Agencywide Documents Access and Management System, Package Accession No. ML24338A255). NRCs comments on the submittal are listed below:
The locations of proposed evaporation tanks A and B (Modutanks), as shown on Sheet 4 of 33, Project Site Plan (1 of 2), are relatively close to the topographic scarp which serves as the boundary between the terrace and the floodplain below, particularly the easternmost portion of evaporation tank B. Sheet 21 of 33, Civil Details (2 of 4), Detail 8 indicates the proposed evaporation tanks are approximately 6 feet in height. Please confirm that a slope stability evaluation was conducted for the area which accounted for the potential loading of the effluent water pumped to the evaporation tanks during operations. A summary of the evaluation, to include the calculations, inputs, and any assumptions, is requested (as appropriate). Alternatively, please explain why such an analysis is not needed.
Most of the pipeline trench plans included in the package appear to extend to depths of 4 feet below ground surface (BGS) or less based on the provided profiles. Sheet 20 of 33, Civil Details (1 of 4), Detail 3 indicates a minimum trench depth below the surface of approximately 3.5 feet. Trench profiles shown on Sheet 10 of 33, Well 1095 Connection Pipeline Plan & Profile and Sheet 11 of 33, North Evaporation Pond Pipeline Plan & Profile indicate stretches of approximately 25 to possibly 250 feet where trench depths exceed 5 feet BGS. Please indicate the anticipated types of trench shoring, benching, and/or sloping which will be used to stabilize the trench walls in the deeper sections of the piping installations (e.g. trench boxes). Will worker entry into the deeper trenches be required to complete the piping construction and surveying tasks?
January 7, 2025
J.
Tallbull 2
Sheet 21 of 33, Civil Details (2 of 4), Section 10, Water Treatment Unit (WTU) Effluent Vault (Section D) indicates the excavation for the vault will exceed 5 feet in depth below the ground surface. Please provide the methods proposed for stabilizing the trench walls in the vault construction effort and any other safety measures proposed to ensure worker safety.
Given the depth, size, and configuration of the proposed WTU Effluent Vault, work conducted within the vault would likely be classified as a confined space entry. Please provide a summary of the standard operating procedures, health and safety protocols, personnel training and atmospheric monitoring requirements, as well as any additional, pertinent requirements (as appropriate) for the construction of and operational access to the WTU Effluent Vault.
Sheet 32 of 33, Instrument & Control Plan indicates the presence of a level meter in each of the evaporation tanks (Level Meters #1 and #2 in tanks A and B, respectively).
Please confirm that these meters are transducers designed to provide water level elevations within each tank and provide the anticipated maximum water level elevation for the tanks.
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
ML25002A232; Ltr ML25002A232 OFFICE NMSS/DUWP
/URMDB NMSS/DUWP
/URMDB NMSS/DUWP
/URMDB NMSS/DUWP
/URMDB NAME KHayes DMandeville RVonTill KHayes DATE Jan 2, 2025 Jan 2, 2025 Jan 7, 2025 Jan 7, 2025