New quake risk analysis needed at San Onofre

Japan's nuclear crisis has focused renewed attention on the need to update seismic risks regarding the aging San Onofre power plant in our North County. KUSI's Ed Lenderman takes look at the safety of San Onofre and calls attention to a notice report that came out in late 2008.

When San Onofre was being built forty years ago, it was designed to withstand a major earthquake. That design was based on geologic fault line data at the time. That data indicated the maximum temblor that could strike was of a magnitude 7.0. San Onofre was designed to withstand an even stronger quake.

Four decades later, however, vast improvements have been made in both our understanding of earthquakes and the technology to map such fault structures, including three dimensional seismic imaging.

Two and a half years ago, the California Energy Commission found that San Onofre could experience a quake larger than a 7.0 and with more frequency than first thought. The report received little attention, needless to say, that's changed.

Rochelle Becker is also referring to the Diablo Canyon Plant in San Luis Obispo County.
Based on the Energy Commission's findings, the State Public Utilities Commission ordered the operators of both plants to use the latest technology to assess risks before seeking renewal of their operating licenses. Diablo's operator, PG&E, filed for a renewal anyway, San Onofre's operator, Southern California Edison, filed an initial report, but it lacked 3-D analysis.

Edison's Chief Nuclear Officer, Pete Dietrich, has declined numerous KUSI interview requests. But he told the Union-Tribune, San Onofre is designed to protect the public in the event of a maximum credible earthquake or tsunami.

“If you had asked the Japanese nuclear regulatory people a week ago today, whether or not this could happen in Japan, you'd have the same answer you're getting from Southern California Edison, can't happen here,” said Becker, “we are not trying to cry wolf, saying no no no, we are saying stop right now, do the studies, tell us whether we can continue to operate these plants in the state of California.”

Wednesday, the administrative law judge for the State Public Utilities Commission canceled, without comment, the August hearing on PG&E's funding for its license renewal. Meanwhile,  the chair of the State Senate Energy Committee has announced he'll hold hearings on the safety issue next month.

Categories: KUSI