Document: NUREG-0800
Document ID: 3cdcec35-dda1-49ce-a003-60e7a1c58ced
Document Type: srp
Title: LOCAL METEOROLOGY
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0707/ML070730395.pdf
Revision Date: 2023-06
Chapter: 2
Section ID: 2.3.2
CFR Part: 
CFR Title: 

Content:
d whether the technical specifications reflect consideration of any identified unique conditions. These review procedures are based on the identified SRP acceptance criteria. For deviations from these acceptance criteria, the staff should review the applicant’s evaluation of how the proposed alternatives provide an acceptable method of complying with the relevant NRC requirements identified in Subsection II. 1. The summaries listed in Section 2.3.2.1 of Regulatory Guide 1.70 and Section 2.3.2.1 of RG 1.206 are reviewed for completeness and adequacy of basic data. The wind and atmospheric stability data should be based on onsite data, because airflow and vertical temperature structure, which can vary substantially from one location to another, are necessary for assessment of atmospheric diffusion conditions at the site. The other summaries should be based on data from nearby representative stations (e.g., within 80 km (50 miles)) with long periods of record because the locally measured values are not likely to provide reliable estimates of the intensity or frequency of extremes. Extreme values are compared to design basis values presented in the safety assessment and are used by other branches to determine whether the meteorological conditions are limiting conditions for design and emergency procedures. When offsite data are used, a determination is made of how well the data represent site conditions and whether more representative data are available. Determinations should be based on distance from the site, surrounding topography, elevation, land use (e.g., urban versus rural), nearby 2.3.2-5 Revision 3 - March 2007 bodies of water, and data collection procedures. National Oceanic and Atmospheric Administration (NOAA) National Climatic Data Center summaries (Refs. 7 and 8) and other standard climatological summaries related to structural design (e.g., Refs. 9 and 10) are used by the reviewer to evaluate the representativeness of stations and periods of record. The