Document: NUREG-0800
Document ID: 65016276-60eb-4e87-829e-1ac16de720b3
Document Type: srp
Title: Probabilistic Seismic Hazard Analysis and Controlling Earthquakes.  For CEUS
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1230/ML12301A010.pdf
Revision Date: 2023-06
Chapter: 2
Section ID: 2.5.2.4
CFR Part: 
CFR Title: 

Content:
sites relying on CEUS-SSC model and data bases, the staff will review the applicant's PSHA, including the underlying assumptions and how the results of the site investigations are used to update the existing sources in the PSHA, how they are used to develop additional sources, or how they are used to develop a new data base. To meet the requirements of 10 CFR 100.23, this subsection is acceptable when adequate information is provided to demonstrate that the PSHA adequately characterizes the regional and local seismic hazard with respect to ground motion and its uncertainty and the controlling earthquakes for the site, as defined in RG 1.208. In addition to seismic sources, the staff will also review the ground motion attenuation models used in the PSHA. For the CEUS, the staff has previously reviewed and accepted ground motion models developed in Electric Power Research Institute (EPRI) Report 1009684. Use of the EPRI ground motion models is acceptable as long as an adequate investigation has been carried out to provide confidence that there are no significant updates or new models that may impact on the results of the PSHA. For sites located in the WUS, the latest attenuation relationships (based on current and extensive strong motion data bases) should be used for the PSHA. Updates or modifications to existing attenuation relationships should be conducted consistent with the methods described in NUREG/CR-6372, “Recommendations for Probabilistic Seismic Hazard Analysis: Guidance on Uncertainty and Use of Experts” and NUREG-2117, “Practical Implementation Guidelines for SSHAC Level 3 and 4 Hazard Studies.” Specifically, the staff will review (1) the rationale for the inclusion of each model, (2) consideration of both aleatory and epistemic uncertainty, (3) model weighting, (4) magnitude conversion, (5) distance measure adjustments, and (6) the model parameters for each spectral frequency. For each PSHA, the staff will also examine how logic trees for seismic