Document: NRC Regulatory Guide
Document ID: cfc61809-5745-460f-8a26-13c168659924
Document Type: regulatory_guide
Title: Identification and Characterization of Seismic Sources and Determination of Safe Shutdown Earthquake Ground Motion
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML0037/ML003740084.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.165
CFR Part: 
CFR Title: 

Content:
5 and 10 Hz (as stated earlier, the staff used the LLNL meth odology and associated results as documented in Refs. B.1 and B.2). Step 2 Calculate the composite annual probability of ex ceeding the SSE for spectral responses at 5 and 10 Hz using median hazard estimates. The composite annual probability is determined as: Composite probability = 1/2(al) + 1/2(a2) where al and a2 represent median annual probabil ities of exceeding SSE spectral ordinates at 5 and 10 Hz, respectively. The procedure is illustrated in Figure B-1. Step 3 Figure B-2 illustrates the distribution of median probabilities of exceeding the SSEs for the plants in Table B.1 based on the LLNL methodology (Refs. B.1 and B.2). The reference probability is simply the me dian probability of this distribution. For the LLNL methodology, this reference proba bility is 1E-5/yr and, as stated earlier, is also to be used in conjunction with the current EPRI methodology (Ref. B.3) or for sites not in the CEUS. 1.165-12 K Table B.A Plants/Sites Used In Determining Reference Probability Soil Condition Soil Condition Plant/Site Name Primary/Secondary* Plant/Site Name Primary/Secondary* limerick Rock Byron Rock Shearon Harris Sand - S1 Clinton Till - T3 Braidwood Rock Davis Besse Rock River Bend Deep Soil LaSalle Till - T2 Wolf Creek Rock Perry Rock Watts Bar Rock Bellefonte Rock Vogtle Deep Soil Callaway Rock/Sand - S1 Seabrook Rock Comanche Peak Rock Three Mile Is. Rock/Sand - S1 Grand Gulf Deep Soil Catawba Rock/Sand - S1 South Texas Deep Soil Hope Creek Deep Soil Waterfoid Deep Soil McGuire Rock Millstone 3 Rock North Anna Rock/Sand - S1 Nine Mile Point Rock/Sand - S1 Summer Rock/Sand - S1 -Brunswick Sand - S1 Beaver Valley Sand - Si *If two soil conditions are listed, the first is the primary and the second is the secondary soil condition. See Ref. B.1 for a discussion of soil conditions. 1.165-13 al >11 4---• " tW I 5 Hz Spectral Response Median Hazard Curve 10 Hz Spectral Response Median Hazard Curve