Document: NUREG-0800
Document ID: 3e2b0f8e-404f-49b4-8dde-3452e69e6218
Document Type: srp
Title: PROBABLE MAXIMUM FLOOD (PMF) ON STREAMS AND RIVERS
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070241.pdf
Revision Date: 2023-06
Chapter: 2
Section ID: 2.4.3
CFR Part: 
CFR Title: 

Content:
will summarize the 16 17 applicant's and staff's estimates of the peak PMF runoff rate and water level (including allowance for coincident wind-generated wave activity) at the site. If the applicant's estimates are within the criteria (described in subsection II), staff concurrence will be stated. If the staff's estimates are 5% more conservative than the applicant's estimates, if the flood conditions may adversely affect the proposed plant, and if the applicant has been unable to support his estimates, a statement requiring use of the staff bases will be made. If the flood conditions do not constitute a design basis, the findings will so indicate. For operating license (OL) reviews that have received detailed PMF reviews during the CP 18 review, or a COL reviews that references an early site permit, the CP or early site permit 19 20 conclusions will be referenced. Any flood potential not identified during the CP review will be noted. If Regulatory Guide 1.59, Position 2, is elected by the applicant, a statement describing lesser design bases will be included in the findings with a staff conclusion of adequacy. A sample statement for a CP review follows: The staff concludes that the plant flood design meets the requirements of General Design Criterion 2 and 10 CFR Part 100 and is acceptable. This conclusion is based on the following evaluation: The probable maximum flood (PMF) resulting from the probable maximum precipitation (PMP) on the ABC River drainage basin yielded an estimated maximum stillwater level at the intake structure on the D & E Canal of about 5.0 feet 1.5 m (5.0 ft) MSL, which 21 is about 5 feet 1 m (5 ft) below its design flood level. 22 The PMF resulting from a local PMP storm on the drainage basins for the small streams near the site yielded an estimated maximum stillwater level of about 60 feet 18 m (60 ft) MSL, which is about 20 feet 6 m (20 ft) below plant grade. 23 24 2.4.3-7 DRAFT Rev. 4 - April 1996 The local PMF resulting from the