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:
Missiles for Nuclear Power Plants” (Ref. 41); and • NUREG-0800, “Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants: LWR Edition.” 1.2.1.3 Considerations, Regulatory Experience, and Staff Position NUREG-0800, Section 2.3.1, “Regional Climatology,” contains the NRC staff’s review procedures for examining the general climate of a region, such as 100-year return periods for extreme weather conditions for winter precipitation, maximum straight-line windspeed, and ambient temperature and humidity, that define a site’s meteorological characteristics. An evaluation of the water requirements for the ultimate heat sink should consider a minimum 30-year weather record and should follow the guidance provided in RG 1.27. The applicability of these and other climatological data to represent site conditions during the expected period of reactor operation should be substantiated. Data and studies on longer term weather cycles should be examined because climate change may affect parameters used to characterize a site and may have an impact on nuclear safety and the environment. Atmospheric extremes that may occur at a site should be considered, even though they are not necessarily critical in determining site suitability, because safety-related SSCs can be designed to withstand most atmospheric extremes (with associated site-specific costs). Current literature on possible weather changes in the site region should also be reviewed to confirm that the methods used to predict weather extremes are reasonable. 1.2.2 Atmospheric Dispersion The atmospheric characteristics at a site are an important consideration in evaluating the dispersion of radioactive effluents from both postulated accidents and routine releases in gaseous effluents. Radiation doses associated with airborne radioactive materials from routine releases and anticipated operational occurrences must be ALARA and must comply with effluent concentration limits. In