Senate to look at earthquake risks at California nuke plant
LOS ANGELES — The Nuclear Regulatory Commission is failing to protect public safety, California Sen. Barbara Boxer charged on Monday, announcing that the Senate committee she chairs will hold hearings on how regulators have assessed earthquake risks at California's last operating nuclear power plant.
Boxer, a Democrat, announced the hearings as The Associated Press disclosed that a federal expert has been urging the NRC to shut the Diablo Canyon plant until regulators can determine whether its reactors can withstand shaking from nearby earthquake faults.
Boxer, chair of the Environment and Public Works Committee, says she is alarmed that the recommendation by Michael Peck, the NRC's former lead inspector at the plant, was made a year ago and that the agency hasn't acted.
The NRC and plant owner Pacific Gas and Electric Co. say the facility is safe.
Peck, who for five years was Diablo Canyon's lead on-site inspector, says in a 42-page, confidential report that the NRC is not applying the safety rules it set out for the plant's operation.
The document, which was obtained and verified by the Associated Press, does not say the plant is unsafe. Instead, Peck's analysis concludes that no one knows whether the facility's key equipment can withstand strong shaking from those faults — the potential for which was realized decades after the facility was built.
Continuing to run the reactors, Peck writes, “challenges the presumption of nuclear safety.”
Peck's July 2013 filing is part of an agency review in which employees can appeal a supervisor's or agency ruling — a process that normally takes 60 to 120 days but can be extended. The NRC, however, has not ruled. Spokeswoman Lara Uselding said in emails that the agency would have no comment on the document.
The NRC, which oversees the nation's commercial nuclear power industry, and Diablo Canyon owner Pacific Gas and Electric Co., say that the nearly three-decade-old facility, whose reactors produce enough electricity for more than 3 million people annually, complies with its operating license, including earthquake safety standards.
PG&E spokesman Blair Jones said the NRC has exhaustively analyzed earthquake threats for Diablo Canyon and demonstrated that it “is seismically safe.” Jones said in an email that the core issue involving earthquake ground motion was resolved in the late 1970s with seismic retrofitting of the plant.
The disaster preparedness of the world's nuclear plants came into sharp focus in 2011. The coastal Fukushima Dai-ichi plant in Japan suffered multiple meltdowns when an earthquake and tsunami destroyed its power and cooling systems. The magnitude-9 earthquake was far larger than had been believed possible. The NRC subsequently directed U.S. nuclear plants to re-evaluate seismic risks, and those studies are due by March.
The importance of such an analysis was underscored on Sunday when a magnitude-6.0 earthquake struck in Northern California's wine country, injuring scores of residents, knocking out power to thousands and toppling wine bottles at vineyards.
U.S. Rep. Lois Capps, a California Democrat whose district includes the plant, said she would push for tough oversight and more studies.
Environmentalists have long depicted Diablo Canyon — the state's last nuclear plant since the 2013 closure of the San Onofre reactors in Southern California — as a nuclear catastrophe in waiting. In many ways, the history of the plant, halfway between Los Angeles and San Francisco on the Pacific coast and within 50 miles of 500,000 people, has been a costly fight against nature.
According to Peck's filing, PG&E research in 2011 determined that any of three nearby faults is capable of producing significantly more ground motion during an earthquake than was accounted for in the design of plant equipment.
The agency should shut the facility until it is proven that piping, reactor cooling and other systems can meet higher stress levels, or approve exemptions that would allow the plant to continue to operate, according to Peck's analysis.
Peck, a senior instructor at the NRC's Technical Training Center in Tennessee, disagreed with his supervisors' decision to let the plant operate without assessing the findings.