Document: NUREG-0800
Document ID: 3921f96a-d11f-4926-8200-7a9d08ba29cc
Document Type: srp
Title: PROBABLE MAXIMUM SURGE AND SEICHE FLOODING
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0523/ML052340539.pdf
Revision Date: 2023-06
Chapter: 2
Section ID: 2.4.5
CFR Part: 
CFR Title: 

Content:
nd waves that may be critical to plant design are considered, and adequate information is supplied to allow a determination that no adverse combinations have been omitted. 7. If Regulatory Guide 1.59, Position 2, is elected by the applicant, the design basis for flood protection of all safety-related facilities identi- fied in Regulatory Guide 1.29 must be shown to be adequate in terms of time required for implementation of any emergency procedures. The applicant must also demonstrate that all potential flood situations that could negate the time and capability to initiate flood emergency procedures are provided for in the less severe design basis selected. This section of the SAR may also state with justification that surge and seiche flooding estimates are not necessary to identify the flood design basis (e.g., the site is not near a large body of water). Hydrometeorological estimates and criteria for development of probable maximum hurricanes for east and Gulf coast sites, squall lines for the Great Lakes, and severe cyclonic wind storms for all lake sites by the Corps of Engineers, National Oceanic and Atmospheric Administration (NOAA), and the staff are used for evaluating the conservatism of the applicant's estimates of severe windstorm conditions, as discussed in Regulatory Guide 1.59. The Corps of Engineers and NOAA criteria require variation of the basic meteorological parameters within given limits to determine the most severe combination that could result. The applicant's hydrometeorological analysis should be based on the most critical combination of these parameters. Data from publications of NOAA, the Corps of Engineers, and other.sources (such as tide tables, tide records, and historical lake level records) are used to substantiate antecedent water levels. These antecedent water levels must be as high as the "10% exceedence" monthly spring high tide plus a sea level anomaly based on the maximum difference between recorded and predicted average water