Senator Blakeslee Testifies At US Senate Hearing on Seismic Risks At California’s Nuclear Power Plants
Today Senator Sam Blakeslee provided the following testimony to the United States Senate Committee on Environment
and Public Works. The hearing was focused upon the nuclear crisis in Japan and the possible implications for the nation’s nuclear power plants.
Senator Blakeslee was invited by Senator Barbara Boxer, Chair of the Committee, to testify on Diablo Canyon nuclear power plant’s seismic
setting and his call for robust 3D seismic studies of the newly discovered offshore fault system located in close proximity to the facility.
Senator Blakeslee, a geophysicist with a Ph.D. in earthquake studies, called for 3D seismic studies in February 2005 after reviewing the existing
geophysical data. The California Energy Commission called for 3D seismic studies in pursuant to Senator Blakeslee’s legislation, AB 1632.
The Shoreline fault was discovered some hundreds of meters from the facility in November 2008. Following the discovery of the Shoreline fault,
Senator Blakeslee authored AB 42 in 2009, requiring 3D seismic studies to be performed at Diablo Canyon. AB 42 was unanimously passed the
California State Legislature, but vetoed by Governor Schwarzenegger.
Testimony is as follows:
My name is Sam Blakeslee, a California state senator, I am a former research scientist who earned a Ph.D. for California earthquake studies
from UC Santa Barbara. A geophysicist I worked a number of years in the oil and gas industry for Exxon, in Houston Texas.
I now live with my wife and two young daughters in San Luis Obispo, 10 miles from Diablo Canyon, one of two operating nuclear power plants in the state of California.
The seismic setting of the Diablo Canyon site has been a source of well-documented controversy for more than four decades.
In 1967, the operator of Diablo Canyon, PG&E stated in their initial permit application the site had only "insignificant faults that
have shown no movement for at least 100,000 and possibly millions of years."
Four years later, using oil industry seismic data, researchers discovered the Hosgri fault only three miles offshore,
which the USGS estimates is capable of a magnitude 7.3 earthquake.
In the end, it took 15 years, major retrofits, and more than $4.4 billion in cost overruns before the plant was operational.
Upon being elected to the California legislature in 2005 I called on PG&E to use more sophisticated oil and gas 3D seismic
imaging technology to assess the complex seismic setting off the coast.
PG&E’s response to my call was a column written by a PG&E vice president stating, “Freshman Assemblyman Sam Blakeslee’s proposed
legislation to conduct another seismic study of Diablo Canyon… is unnecessary and bad policy for our California customers”.
In 2006, Governor Schwarzenegger signed my legislation directing the Energy Commission to perform an independent review the data to
assess the potential seismic vulnerability of the state’s nuclear plants and to provide recommendations.
That same year PG&E moved to initiate the process to relicense Diablo, though there was no compelling need
to rush the process as their current licenses last through 2024 and 2025.
In 2007, while the Energy Commission study was being performed, a Magnitude 6.8 earthquake struck Japan and the largest
nuclear power plant in the world was damaged with 3 of its reactors still shutdown.
In 2008, the Energy Commission issued their report, stating that the uncertainties did in fact exist near the Diablo Canyon Plant,
and that 3D seismic studies were recommended. PG&E’s written response to the Commission was, I quote, [we] “believe there is no uncertainty regarding the seismic setting and hazard at the Diablo Canyon Site”.
Mere weeks later, the USGS discovered the active Shoreline fault running within some hundreds of yards offshore from PG&E’s
nuclear power plant and with an orientation that could potentially intersect with the powerful Hosgri fault.
Within days, PG&E rushed to declare, “We don’t see anything that exceeds the plant’s design basis.”
This statement was made before collecting the data necessary to determine the precise location, length, and relationship
of the Shoreline Fault to the nearby and dangerous Hosgri fault.
Fast forward to the events of just one month ago, when a Magnitude 9.0 earthquake struck offshore Japan on a fault system
believed capable of only a Magnitude 7.9 quake. Like the 2007 earthquake, the 2011 earthquake far exceeded both the Japanese
utility’s seismic and engineering assumptions.
Three weeks ago at a California Senate hearing on the issue I asked PG&E if they continued to maintain their previous
assertion that there was no uncertainty in the seismic setting near the plant. PG&E responded by saying that although
there is always some uncertainty they were, “not concerned about the uncertainty.”
I then asked PG&E to suspend or withdraw its license application with the NRC until the seismic data is in hand to allow
regulators to make informed decisions – because, although they were not concerned about the seismic uncertainty, my community
was very concerned. Yesterday, one day before this hearing, PG&E agreed to take such an action.
After six years of calls for seismic studies, state legislation, recommendations from the Energy Commission,
direction from the California Public Utilities Commission, two devastating Japanese earthquakes, and now a nuclear
disaster of Chernobyl proportions, the utility is finally willing to slow its relicensing effort to collect long overdue
In closing, I have two questions for federal regulators:
First: Now in the aftermath of the Japan crisis, will the NRC strengthen its earthquake hazard review procedures for the two
nuclear facilities that the NRC itself has identified as being located in the nation’s HIGHEST seismic hazard area?
Second: Given the reluctance of PG&E to accept even the need for these studies, what procedures will the NRC put in place for an
objective peer review analysis of the studies to ensure that accurate scientifically robust conclusions are drawn rather than simply
relying upon assurances provided by the utility and in-house NRC staff?
Thank you for this opportunity to testify before you.