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USGS: Increased Likelihood of Megaquake in California
… in the new study, the estimate for the likelihood that California will experience a magnitude 8 or larger earthquake in the next 30 years has increased from about 4.7% for UCERF2 to about 7.0% for UCERF3.

The new likelihoods are due to the inclusion of possible multi-fault ruptures, where earthquakes are no longer confined to separate, individual faults, but can occasionally rupture multiple faults simultaneously,” said lead author and USGS scientist Ned Field. “This is a significant advancement in terms of representing a broader range of earthquakes throughout California’s complex fault system.http://www.usgs.gov/newsroom/article.asp?ID=4146#.VP_kx3-9KSM

Greater or equal to Magnitude 6.7 Probability

Diablo Canyon-San Onofre Nuclear Reactors

They both sit out on the waterfront, making the risk of near-shore tsunami with no warning a special issue.
6.7 M San Onofre-Diablo USGS probability
M 6.7 Quake San Onofre USGS prob.
6.7 or Grter Diablo USGS
http://www.wgcep.org/UCERF3 (2014 Working Group on California Earthquake Probabilities, 2015, UCERF3- USGS)

Increased Risk of M 7.7 or Greater Rupture for UCERF3, compared to UCERF2

The maps appear essentially the same, so apparently risk has doubled for both 5 years and 30 years. The red lines-increased risk clearly impact both San Onofre and Diablo Canyon. San Onofre is no longer operating, but is being “decommissioned” and nuclear waste remains in cooling pools, and will later remain in flimsy Holtec Dry Casks of debatable quality. Some is already in dry casks.

Increased Probability of 7.7 or greater rupture in 5 years
7.7 or Grter Rupture increase Cal 5 years
All M>=7.7 Ruptures, 5 Year Forecast Sub Section Participation Probabilities
http://opensha.usc.edu/ftp/UCERF3-TimeDependentSupplements/m7.7_5yr/SubsectionProbabilityMaps/U3_U2_TimeDep_Ratio.pdf
7.7 or Grter Rupture increase Cal 30 years
http://opensha.usc.edu/ftp/UCERF3-TimeDependentSupplements/m7.7_30yr/SubsectionProbabilityMaps/U3_U2_TimeDep_Ratio.pdf

Locations on map exported from wikipedia: http://en.wikipedia.org/wiki/Diablo_Canyon_Power_Plant
http://en.wikipedia.org/wiki/San_Onofre_Nuclear_Generating_Station

http://pubs.usgs.gov/fs/2015/3009/
http://opensha.usc.edu/ftp/UCERF3-TimeDependentSupplements/m7.7_30yr/SubsectionProbabilityMaps/

We read that this study excludes the Cascadia subduction zone to the north, but cannot find the exact link.