Document: NUREG-0800
Document ID: dfad5166-86ba-4d57-a49c-4a918bb0780d
Document Type: srp
Title: and Section 2.4.9, as described in the corresponding SRP sections.
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0701/ML070100647.pdf
Revision Date: 2023-06
Chapter: 2
Section ID: 2.4.7
CFR Part: 
CFR Title: 

Content:
ubstantiated sufficient information pertaining to the local intense precipitation, flooding causal mechanisms, and the controlling flooding mechanism at the proposed site. Section 2.4.2, “Floods,” of NUREG-0800, Standard Review Plan, provides that the site safety analysis report should address the requirements of 10 CFR Parts 52 and 100 as they relate to identifying and evaluating the local intense precipitation, flooding causal mechanisms, and the controlling flooding mechanism in the vicinity of the site and site regions. Further, the applicant considered the most severe natural phenomena that have been historically reported for the site and surrounding area and reasonable combination of these phenomena in establishing design-basis information pertaining to the local intense precipitation, flooding causal mechanisms, and the controlling flooding mechanism, with sufficient margin for the limited accuracy, quantity, and period of time in which the historical data have been accumulated. The staff has generally accepted the methodologies used to determine the severity of the phenomena reflected in these site characteristics, as documented in safety evaluation reports for previous licensing actions. Accordingly, the staff concludes that the use of these methodologies results in site characteristics containing sufficient margin for the limited accuracy, quantity, and period of time in which the data have been accumulated. In view of the above, the site characteristics previously identified are acceptable for use in establishing the design bases for SSCs important to safety, as may be proposed in a COL or CP application. Therefore, the staff concludes that the identification and consideration of the local intense precipitation, flooding causal mechanisms, and the controlling flooding 3 References for PMP estimates, time distribution, etc., are in SRP Section 2.4.3. 2.4.2-15 Revision 4 - March 2007 mechanism set forth above are acceptable and meet the requirements of