Document: NRC Regulatory Guide
Document ID: d1045e85-64b0-4a83-8450-067a4fcd130f
Document Type: regulatory_guide
Title: Atmospheric Dispersion Models for Potential Accident Consequence Assessments at Nuclear Power Plants + HISTORY –HISTORY 04/2014 – Periodic Review of Revision 1 – Reviewed with issues for future consideration 02/1983 – Reissued 02/1983 to correct page 1.145-7 (Rev. 1)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML0037/ML003740205.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.145
CFR Part: 
CFR Title: 

Content:
U.S. NUCLEAR REGULATORY COMMISSION Revision 1 November 1982 REGULATORY GUIDE OFFICE OF NUCLEAR REGULATORY RESEARCH (Reissued February 1983 to correct page 1.145-7) REGULATORY GUIDE 1.145 ATMOSPHERIC DISPERSION MODELS FOR POTENTIAL ACCIDENT CONSEQUENCE ASSESSMENTS AT NUCLEAR POWER PLANTS A. INTRODUCTION Section 100.10 of 10 CFR Part 100, "Reactor Site Criteria," states that meteorological conditions at the site and surrounding area should be considered in determining the acceptability of a site for a power reactor. Section 50.34 of 10 CFR Part 50, "Domestic Licensing of Produc- tion and Utilization Facilities," requires that each applicant for a construction permit or operating license provide an analysis and evaluation of the design and performance of structures, systems, and components of the facility with the objective of assessing the risk to public health and safety resulting from the operation of the facility. Section 50.34 of 10 CFR Part 50 also states that special attention should be directed to the site evaluation factors identified in 10 CFR Part 100 in the assessment of the site. The regulatory positions presented in this guide repre- sent a substantial change from procedures previously used to determine relative concentrations for assessing the potential offsite radiological consequences for a range of postulated accidental releases of radioactive material to the atmosphere. These procedures now include consideration of plume meander, directional dependence of dispersion conditions, and wind frequencies for various locations around actual exclusion area and low population zone (LPZ) boundaries 3 The direction-dependent approach provides an improved basis for relating the Part 100-related review of a proposed reactor to specific site considerations. Accordingly, this guide provides an acceptable methodology for deter- mining site-specific relative concentrations (X/Q) and should be used in determining xJQ values for the evalua- tions discussed in