Diablo Canyon: PG&E Secretly Used Wrong Design Data for Key Safety Equipment for 30 Years

SAN FRANCISCO - Pacific Gas & Electric Co. used incorrect earthquake and accident data when building crucial safety equipment for the Diablo Canyon nuclear power plant, according to information released by Senator Barbara Boxer. Friends of the Earth said the revelation suggests that PG&E has acted with gross negligence and that the twin-reactor plant on California’s Central Coast should be immediately shut down pending a public investigation.

Correspondence from the U.S. Nuclear Regulatory Commission -- released by Sen. Boxer in a recent hearing and reported Sunday on Page 1 of the San Francisco Chronicle (PDF) -- shows that since Diablo Canyon’s first reactor came online in 1984, PG&E failed to use updated seismic and loss-of-coolant-accident data, known as LOCA loads, for replacement equipment. Failure of such equipment in an earthquake could lead to a catastrophic release of radiation. PG&E should have used new data after a previously unknown fault, the Hosgri, was discovered during initial construction, but violated its federal operating license by failing to use the updated data in conjunction with loss of cooling accident data in designing and constructing replacement steam generators and reactor vessel heads for the reactors.

In 2011, PG&E notified the NRC of its decades-long negligence, but incredibly, the NRC failed to cite PG&E for any infraction. Instead NRC and PG&E worked together to secretly and illegally alter the plant’s operating license in September 2013. Friends of the Earth has a case pending in the U.S. Court of Appeals asking that the illegal license revision be thrown out and that Diablo Canyon be shut pending public review to determine whether or not the reactors can withstand the forces of newly identified earthquake faults that surround the plant.

Instead of addressing its malfeasance, PG&E launched an internal effort to try to show that despite using the wrong design data, the equipment it had installed was OK. PG&E has asked the California Public Utilities Commission for $133.5 million from ratepayers for what it calls a “Licensing Basis Verification Program.” The utility did not explain that they were asking to bill their customers for a paper exercise to cover up its negligence in the faulty design of well over $1 billion worth of equipment, also paid by customers.

Since the Hosgri Fault was discovered, new research has revealed that at least four faults surrounding Diablo Canyon are capable of causing earthquakes more powerful than the reactors were designed to withstand The plant’s former NRC senior resident inspector, Dr. Michael Peck, warned last year that the increased risks from earthquakes meant that the plant was operating outside of its license and should be shut pending review -- a warning that came before the revelations about PG&E’s use of outdated safety data.

“This shows gross negligence by PG&E and a shameful lack of oversight by federal regulators,” said Damon Moglen, senior strategic advisor to Friends of the Earth. “It’s terrifying to think that for 30 years PG&E used the wrong numbers for vital equipment at the U.S. reactors most at risk from earthquakes.”

“No one would dream of putting nuclear reactors in that location today,” Mogen said. “Diablo Canyon should never have been constructed in the first place, and now it is clear it should not be allowed to operate another day. Diablo Canyon must be shut down now, and there should be both state and federal investigations into PG&E’s negligence.”

Dave Freeman, former head of the federal Tennessee Valley Authority, the Los Angeles Department of Water and Power and the Sacramento Municipal Utility District, said PG&E’s negligence fits the utility’s pattern of cutting corners on safety, which led to the fatal gas pipeline explosion in San Bruno in 2010.

“There they go again,” said Freeman, now senior energy advisor to Friends of the Earth. “Just as with San Bruno, PG&E has again put profits before safety, has misused ratepayers’ money and misled state regulators at the PUC.”