WASHINGTON - Friends of the Earth has petitioned (pdf) the U.S. Court of Appeals to overturn a secret decision by the Nuclear Regulatory Commission to illegally alter the operating license for the Diablo Canyon nuclear power plant allowing Pacific Gas and Electric to hide the fact that the reactors are vulnerable to earthquakes stronger than it was meant to withstand.

The secret revision of Diablo Canyon’s license was revealed in NRC documents rejecting a dissent by the plant’s former senior resident inspector. The inspector, Dr. Michael Peck, defied his superiors in saying that Diablo Canyon was operating in violation of its license and should be shut down unless and until new seismic information was addressed.

In a July 2013 formal dissent, which the NRC suppressed for more than a year, Dr. Peck argued that newly discovered faults could produce earthquakes far more destructive than the plant was designed, built and licensed to withstand. Last month, in rejecting the dissent, the NRC revealed that in September 2013 it had changed the way the risk of earthquakes at the plant are assessed -- in effect, rewriting history and science to make the threat of more powerful earthquakes go away, without requiring any safety upgrades by PG&E.

The amendment was added in secret, unknown beyond the highest levels of PG&E and the NRC. Today Friends of the Earth petitioned the U.S. Court of Appeals for the D.C. circuit to review the amendment, overturn it and order a public license amendment proceeding as required by federal law.

“PG&E’s new seismic study reveals that the earthquake threat at Diablo -- if measured by its original license -- could be far greater than that for which the reactors were designed.  So PG&E and the NRC secretly amended the license to relax the safety requirements,” said David Freeman, former head of the Tennessee Valley Authority, Los Angeles Department of Water and Power and the Sacramento Municipal Utility District. “This is not only illegal, it’s an outrage.”

PG&E has enough trouble on its hands from the San Bruno explosion, where they had also claimed they had put safety first,” said Freeman,  senior advisor to Friends of the Earth. “This secret action shows they don’t put safety first.  Thank goodness there are courts in America that can give us an independent decision.”

Under federal law and NRC regulations, changing the way seismic risk or reactor durability is assessed requires a public license amendment review. Instead, in consultation with PG&E, the NRC inserted a secret revision to the plant’s license, which changed both the scientific calculations for assessing earthquake risks and retroactively declaring that the reactors were strong enough to withstand far greater seismic activity.

“At Diablo, it is now clear that these outdated 1960s-era reactors are not built to withstand the earthquake risks that surround the plant,” said Damon Moglen of Friends of the Earth.  “But instead of making them address these safety issues, the NRC worked with  PG&E to change the rules. It’s a scandal of the first order, and frankly very scary.”

A PG&E report released last month revealed that a newly discovered fault, located just 650 yards from the plant, is twice as long as the utility had maintained since 2011. The report also acknowledged one of Michael Peck’s most troubling concerns; that the new fault is connected to two others and together the three are capable of producing much stronger shaking than the plant was designed and licensed to withstand.

In the aftermath of the Fukushima nuclear disaster, a 2011 NRC study indicated that Diablo Canyon is the nuclear power plant in the U.S. most likely to fail in response to an earthquake larger than it was designed to withstand.