ML25161A264

OEDO-24-00083 - Directors Decision Regarding Seismic Core Damage Frequency for Diablo Canyon Nuclear Power Plant, Units 1 and 2 (EPID L-2024-CRS-0000) - Attachment

ML25161A264
Person / Time
Site:	Diablo Canyon
Issue date:	06/26/2025
From:	Dennis Galvin NRC/NRR/DORL/LPL4
To:
References
EPID L-2024-CRS-0000, OEDO-24-00083
Download: ML25161A264 (1)

Text

Figure 1 Location of Diablo Canyon relative to major regional active fault systems that contribute the most to the hazard. (NUREG/KM-017 (ML21344A126))

Noto Pacific Eurasia Oshkosh Yangtze Okinawa Amur Figure 2 Location of the Noto Peninsula relative to the Amur and Oshkosh microplates.

(Wikipedia commons:

https://commons.wikimedia.org/wiki/File:Tectonic_plates_boundaries_detailed-en.svg)

Figure 3 USGS modeled slip distribution for 2024 Noto earthquake (https://earthquake.usgs.gov/earthquakes/eventpage/us6000m0xl/finite-fault)

Figure 4 Geologic map showing a triangular region bounding the California Coast Range with many NW striking faults that cut through Ceneozoic Era (66 Mya) sedimentary rocks that overlie older Mesozoic Era (252-66 Mya) basement rocks.*

• Langenheim, V. E., R. C. Jachens, R. W. Graymer, J. P. Colgan, C. M. Wentworth, and R. G. Stanley, Fault geometry and cumulative offsets in the central Coast Ranges, California: Evidence for northward increasing slip along the San Gregorio-San Simeon-Hosgri fault, Lithosphere, 5(1), 29-48, 2013.

Figure 5 Focal mechanisms of earthquakes near Diablo Canyon (NUREG/KM-017 (ML21344A126))

Figure 6 Locations of historical earthquakes in Central Coastal California from PG&Es SSC model SSHAC report. Modified to show location of Diablo Canyon site and 50 km radius.

(ML15071A046)

Diablo Canyon 50 km radius from Diablo Canyon Figure 7 from the NRC staffs confirmatory analysis of PG&Es hazard models shows the Hosgri, Shoreline, Los Osos, San Luis Bay, and the 18 virtual faults as dashed lines (ML16341C057).

Los Osos Fault San Luis Bay Fault Shoreline Fault Hosgri Fault Figure 8 Petitioner modified PG&E cross section with petitioners interpretation of subsurface fault geometry. Slide is from petitioner presentation (ML24198A105).

• Langenheim, V. E., R. C. Jachens, R. W. Graymer, J. P. Colgan, C. M. Wentworth, and R. G. Stanley, Fault geometry and cumulative offsets in the central Coast Ranges, California: Evidence for northward increasing slip along the San Gregorio-San Simeon-Hosgri fault, Lithosphere, 5(1), 29-48, 2013.

Figure 9. Profile taken from Langenheim et al.,* across the Irish Hills showing the magnetic and gravity data and model fits along with a geologic cross section that provides the modeled density and magnetic susceptibility values.