NRC fails to apply standard earthquake protocols to Diablo Canyon Nuclear Plant

November 13, 2013


The Nuclear Regulatory Commission is not holding the Diablo Canyon nuclear plant in California to the same standards it requires of every other nuclear facility to address potential earthquake hazards, according to a report released today by the Union of Concerned Scientists. UCS prepared the report, “Seismic Shift: Diablo Canyon Literally and Figuratively on Shaky Ground,” for the Alliance for Nuclear Responsibility.

“This is a dangerous double standard,” said David Lochbaum, director of UCS’s Nuclear Safety Project and author of the report. “At other facilities, the NRC enforced its safety regulations and protected Americans from earthquake threats. Today, in the case of Diablo Canyon, the NRC is ignoring its regulations, unfairly exposing millions of Americans to undue risk.”

It is widely known that Diablo Canyon sits near earthquake fault lines. In late 2008, the plant’s owner, Pacific Gas & Electric (PG&E), informed the NRC about a previously unknown earthquake fault line running as close as 2,000 feet from Diablo Canyon’s two reactors that could cause more ground motion during an earthquake than the plant was designed to withstand. Since this new fault was discovered, the NRC has not demonstrated that the reactors meet agency safety regulations.

When similar concerns surfaced at nuclear facilities in California, Maine, New York, Pennsylvania and Virginia, the NRC did not allow the plants to continue to operate until the agency determined they met safety regulations. In particular, the NRC needed to be sure that a number of devices, including “shock absorbers” on piping and other components, would limit earthquake damage. In contrast, the NRC has allowed PG&E to continue to operate Diablo Canyon’s reactors despite this known threat.

For example, in March 1979, the NRC ordered Beaver Valley Unit 1 in Pennsylvania, FitzPatrick in New York, Maine Yankee, and Surry Units 1 and 2 in Virginia to shut down after it discovered an error in the computer code that analyzed earthquakes and associated protective features of these plants. The agency did not allow the five reactors to resume operating until plant owners reevaluated earthquake hazards, input proper computer codes, and installed or upgraded protection devices to better protect the plants from earthquakes. The burden of proof was on each of these facilities to demonstrate compliance with federal safety regulations.

“Despite solid evidence that Diablo Canyon does not comply with federal safety requirements, the NRC continues to allow the plant to operate,” said Rochelle Becker, executive director of the Alliance for Nuclear Responsibility. “The NRC should enforce its safety regulations at Diablo Canyon.”

The Union of Concerned Scientists puts rigorous, independent science to work to solve our planet’s most pressing problems. Joining with citizens across the country, we combine technical analysis and effective advocacy to create innovative, practical solutions for a healthy, safe and sustainable future. For more information, go to


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This should be a HUGE wake up call, especially for folks who work at the plant.

These concerned and knowledgable scientists don’t even live around here but feel the issue is so important, the danger so acute, putting the lives of so many people at risk, that they are going out of their way to publish their concerns and BACK UP those concerns with FACTS, for the sake of you and I and all the others who live on the Central Coast.

Then we have the fools who don’t know or care about the facts, who urge everyone to disregard these fair and responsible warnings. They try to turn it into some political or ideological debate when in reality it is nothing of the kind. It is a matter of simple public safety and responsibility that transcends petty politics.

Those who have “dislike”ed your comments are simply wingnut fools.

After doing some research on the UCSUSA website, looking at their financial reports (following the money), this is a basic global non-profit science advocacy group (global warming). Nothing wrong with that is that is what you support.

I am always suspicious of a financial report that does not post or break out salaries under their expenses but hide it on their annual financial statements. Not a good sign.