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:
d in subsection II above), staff concurrence will be stated. If the applicant's estimates do not meet the criteria in subsection II above, and the-proposed plant may be adversely affected, a statement requiring use of the staff's estimates for the design basis will be made. If the flood conditions do not constitute a design basis, the statement will so indicate. For operating license (OL) reviews of plants which have received detailed reviews during the CP review, the CP conclusions will be referenced. However, a review will be made to assure that protection against the design-basis water level conditions established in the CP review has been properly implemented. In addition, a review of surge and seiche history since the CP review will be made. Any new information or improvements in predictive models will be noted. If no detailed CP review was undertaken, this fact will be indicated in the OL findings. If Regulatory Guide 1.59, Position 2, is elected by the applicant for protection, a statement describing lesser design bases will be included in the findings with the staff conclusion of adequacy. A sample statement for an OL review follows: The design basis hurricane-induced high and low stillwater levels were established during the CP review at elevations 22.0 feet MSL and -7.5 feet MSL, respectively. These levels are based upon the estimated water levels, exclusive of wave action, that would occur during passages of a probable maximum hurricane (PMH) to the south and north, respectively, of the plant. At the request of the staff, the applicant analyzed the wave conditions on safety-related facilities that could accompany the 22 foot MSL surge level. The results of these analyses indicate the most severe wave action would be restricted to the canal, and that high ground levels would 2.4.5-4 Rev. 2 - July 1981 limit wave heights in the vicinity of exposed safety-related buildings, except the service water intake, to 1.6 feet. For the intake, the applicant has