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:
ceed 500 ppsm out to twice the calculated distance at which the 1 rem TEDE is estimated for a major accident with consideration of containment performance during severe accidents is sufficient to meet the requirements of 10 CFR 100.21(h). In the case that an applicant can show that the calculated offsite dose does not exceed 1 rem TEDE for the 30-day exposure period, the siting of a reactor might not be determined by population-density considerations but would instead be governed by the regulatory requirement in 10 CFR 100.21(b) for reactors to be located distant from densely populated centers with more than about 25,000 residents.. However, an advanced reactor with estimated doses below 1 rem at the site boundary over the month following the assumed postulated accident could be sited within towns with populations of no more than approximately 25,000 residents. A-3.3 For Non-LWRs Not Using RG 1.233 and Using Traditional Analysis of a Containment-Type Barrier Non-LWR applicants choosing not to use a methodology like that in RG 1.233 and the related event-specific modeling of mechanistic source terms may use a traditional or deterministic approach to establish the requirements for a containment-type barrier for limiting the release of radionuclides.i Since this approach will be seen as limiting for the required safety analyses compared to a more fully developed mechanistic source term for a range of event sequences, the applicant would need to develop a conservative, design-specific bounding core damage accident source term like that given in RG 1.183 for LWRs. The source term based on an estimate of a mixture of radionuclides breaching barriers upstream of the containment, along with associated energy additions (e.g., accounting for increased temperatures and pressures) from DBAs, is used to confirm or establish performance requirements, including maximum leak rates, for the containment features using the existing criteria for doses at the exclusion area boundary i