A seismic hazard update is currently being conducted for the Diablo Canyon Power Plant (DCPP) Site under the Senior Seismic Hazard Analysis Committee (SSHAC) Level 3 process. The SSHAC Level 3 process is a formal, structured procedure for developing Seismic Source Characterizations (SSC) and Ground Motion Characterizations (GMC), and has been identified in Nuclear Regulatory Commission regulatory guidance (RG 1.208) as an acceptable method for use in performing probabilistic seismic hazard analysis (PSHA) for nuclear sites.
The SSC and GMC for the DCPP site will involve complex assessments due to the location of the site within an active tectonic region of the United States. The seismic safety issues at DCPP will be subject to significant public and regulatory scrutiny. The SSHAC Level 3 update will re-examine parameters of the GMC and SSC in light of recent and ongoing studies with the objective of developing updated models that capture the center, body, and range (CBR) of the technically defensible interpretations (TDI).