Document: NRC Regulatory Guide
Document ID: 239cc7c1-f2cb-46cc-945d-8009db28aa6c
Document Type: regulatory_guide
Title: General Site Suitability Criteria for Nuclear Power Stations + HISTORY - HISTORY 12/2023 – DG-4034 , Proposed Revision 4 12/2011 – DG-4021 , Proposed Revision 3 02/1995 – DG-4004, Second Proposed Revision 2 11/1992 – DG-4003, Proposed Revision 2 (Rev. 4)
Source: NRC Regulatory Guide Division 4
Source URL: https://www.nrc.gov/docs/ML2312/ML23123A090.pdf
Revision Date: 2023-10
Chapter: 
Section ID: RG-4.7
CFR Part: 
CFR Title: 

Content:
cle Planning” (Ref. 67). 2.2.4.4 Considerations, Regulatory Experience, and Staff Position As specified in 10 CFR 100.20(c), the site’s physical characteristics (including seismology, meteorology, geology, and hydrology) must be considered when determining its acceptability for a nuclear power reactor. Special precautions should be planned if a reactor is to be located at a site where a significant amount of radioactive effluent might find ready access to ground water. According to 10 CFR 100.20(c)(3), factors important to hydrological radionuclide transport (such as soil, sediment, and rock characteristics; adsorption and retention coefficients; ground water velocity; and distances to the nearest surface body of water) must be obtained from onsite measurements. To satisfy the hydrologic requirements of 10 CFR Part 100, applicants should verify ground water conditions at a proposed site and assess how plant construction and operation will affect those conditions. This provides assurance that the release of radioactive effluents from the plant will not significantly affect ground water at or near the plant site. To assess radionuclide retention and transportation through ground water, the following information should be determined for the site: • soil, sediment, and rock characteristics (e.g., grain size, hydraulic conductivity, fracturing); • chemistry of the subsurface media; • source of radioactivity, radionuclide, and radioactivity inventories, and assumed release mechanism from the nuclear island, considering plant design features; • site-specific adsorption coefficients for radionuclides of concern in the subsurface soils and backfills/structural fills (ASTM C1733 provides guidance for obtaining distribution coefficients, especially for radionuclides); • preferential flow in the subsurface and other physiographic conditions (to evaluate the most severe impact on people and the environment and to conservatively estimate contaminant travel time);