Document: NUREG-0800
Document ID: c6f1872f-6590-4af8-b290-f6ec212570a9
Document Type: srp
Title: GROUNDWATER
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0707/ML070730443.pdf
Revision Date: 2023-06
Chapter: 2
Section ID: 2.4.12
CFR Part: 
CFR Title: 

Content:
tion, construction of future wells and reservoirs, accidents, pipe failures, or other natural events. 3. Reliability of Groundwater Resources and Systems Used for Safety-Related Purposes: If wells are proposed for safety-related purposes, the hydrodynamic design bases (and development thereof) for protection against seismically induced pressure waves should be described and be consistent with site characteristics. If onsite groundwater use and facilities are safety-related, the criteria of Regulatory Guide 1.27 should be applied. 4. Reliability of Dewatering Systems: If a permanent dewatering system is employed to lower design basis groundwater levels, the bases for the design of the system and determination of the design basis for groundwater levels are reviewed. Information regarding (a) all structures, components, and features of the system; (b) the reliability of the system as related to available performance data for similar systems used at other locations; (c) the various soil parameters (such as permeability, porosity, and specific yield) used in the design of the system; (d) the bases for determination of groundwater flow rates and areas of influence to be expected; (e) the bases for determination of time available to mitigate the consequences of system failure where system failure could cause design bases to be exceeded; (f) the effects of malfunctions or failures (such as a single failure of a critical active component or failure of circulating water system piping) on system capacity and subsequent groundwater levels; and (g) a description of the proposed groundwater level monitoring program and outlet flow monitoring program should be reviewed. For dewatering systems, calculations should be performed to determine phreatic surfaces, normal flow rates, flow rates into the system as a result of pipe breaks (circulating and service water system pipes), groundwater rebound times assuming total failure of the system, and system capacity. 5. Consideration of