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


Inline Feedbacks
View all comments

“On March 11, 2011, a 9.0-magnitude earthquake struck Japan and was followed by a 45-foot tsunami, resulting in extensive damage to the nuclear power reactors at the Fukushima Dai-ichi facility. The NRC has taken significant action to enhance the safety of reactors in the United States based on the lessons learned from this accident”.

U.S.NRC September 2013

Really? Like allowing a reactor, Diablo Canyon, to operate in dangerously close proximity of the Los Osos, Hosgri, San Andreas and recently discovered Shoreline faults?! Explain to me what “significant action” could be taken other than to close it down, dismantle it and do whatever it takes to “contain” the waste?

Besides, wasn’t the construction safety questioned in the first place when it was found out In 1981 that added structural supports to reinforce stability in case of earthquake were needed? And that these supports were shown in a single set of blueprints where workers were supposed to reverse the blueprints when switching to the second reactor, but didn’t?! Didn’t this leave some structural supports that needed reinforcing unchanged? Yes, that did happen! In 1982 the NRC decided not to reverse, let alone review, its 1978 decision approving the plant’s safety, despite these and many other design errors (if this has been addressed,and these structures reinforced, please provide me with a source as I cannot find anything to the contrary).

And now any of you want to question the validity and or motivation of the UCS? Good God! You had better hope that more than your head is buried in the sand when, and I mean when, Diablo gets hit by a significant earthquake and whatever part of your body you haven’t buried gets torched!

Just sayin’….

There’s a REASON the top boss for Diablo Canyon Nuclear Power Plant lives HUNDREDS OF MILES away.

Nuclear Power might be acceptable if the power plants are top notch, utilizing the best available technology, AND they are managed by a reputable company. Unfortunately, at Diablo Canyon we have neither.

If PG&E was a good steward it would make sure Diablo was meeting higher standards.

It seems corporate culture at many of the companies that run nuclear plants has devolved over the years and there are too many compromises of public safety in order to make sure a lot of people who work there get stunningly rich on the backs of the ratepayers.

Employees at the plant need to start coming forward. It’s the right thing to do.

Those of you who choose to turn a blind eye to the Fukushima disaster will some day suffer the wrath of Mother Nature and all her fury. By then, it may be too late.

While I partially agree with you, we also have to remember that “tree huggers” have been crying doom and dreaming of mother earth exacting her revenge for decades. Still, there are some valuable lessons with Fukushima, more even than Chernobyl gave us (and it’s has serious problems to this day).


Tree Huggers? Don’t you mean Environmental Activists? Or are you just another

ill-informed “tree killer” using a term to demonize and marginalize something you don’t agree with, understand or have one iota of informed information on?

The “doom” you speak of is happening everyday, every single day! Just because it isn’t blowing up in your face doesn’t mean that “mother earth” isn’t taking out its revenge. Climate change, man driven climate change, is a reality! The stripping of our planet of its natural resources without regard to its consequences is a reality! Pollution at a scale that has already reached a point of no return in some places is a reality! Over fishing our oceans is a reality! What more do you need? Maybe Diablo Canyon gettin’ shook to pieces and irradiating the entire coast line? You’d probably still be sayin’ its all a hoax even when you’re set aglow….

And what of mother earths revenge? No, it doesn’t have to blow up to prove its point; maybe not being able to support us as a species is revenge enough. Yea, I know; it’s doin’ just fine right now, right? Maybe, just maybe the “tree killer” should be a bit more far sighted and consider the planet he’s leaving to his kids, grand kids, great grand kids and all the others who come after them.

Ah Hell, rOy! Hug a tree just once! Maybe you’ll get hugged back! Ya never know!

Just sayin’…

How? With all this doom “happening everyday, ever single day” I now fear leaving my bunker. Apparently, we’re all hanging on by just a thread. Once all the humans have been removed from the planet, it will be safe for me to come out and hug trees.

Right on cue, here come the indignant replies from the peanut gallery (slobird, catdude – hey, you two should get together!). Did you even take 30 seconds to look into who the Union of Concerned Scientists is and what they do? I nominate the two of you to head the Union of Uneducated Ignoramuses!

I did check into it and you still don’t think the Mothers for Peace has their fingerprints on this? Who might need to head the UUI?

UCS often has hangers-on for many of their criticisms. In fact, they only put out criticisms, that is their job it seems. Squeaky wheel and all. That said, David Lochbaum is a pretty stand-up guy, coming from the Nuclear Industry and having real concerns over the safety of the plants, etc. He is a decent watchdog that I do not mind having look over the shoulder of the NRC or other government agency.

As for Mothers for Peace, well, they’ll stand with anything that they feel aligns with their agenda – whether the UCS wants their support or not.

In the end, we’re asking more questions of the NRC now because of UCS, so that is good. It is good to ask serious, and probing questions – especially when Nuclear power plant safety is the topic.

Mothers for Peace? What do they have to do with it? Their name isn’t even in the story. Anyway, where are the fingerprints you claim are on “this”? Would be nice if you could back up your claim with some hard evidence.

Actually, I have a B.S. in engineering and make my living with a hi-tech business I started myself 27 years ago. I actually have the ability to think critically, unlike many of the posters here. Just because you do not like the Union of Concerned Scientists does not negate their opinion. And your qualifications? You probably think a “jet fuel” (kerosine!) fire can cause a building to implode in a controlled demolition… LOL

“I actually have the ability to think critically, unlike many of the posters here.”



From one peanut gallery participant to another… SHUT UP!

We are all in this “peanut gallery” don’t you know… Kept in the dark by the powers in charge as not to be able to come out of the galleries and on to the main floor to participate in the debate. And when one of us does take that step down, UCS in this case, there is always someone like you that wants to keep them in the gallery to keep your Uneducated Ignoramus Ass company.

Even though I don’t always agree with science, i.e. Big Bang Theory, Darwinism, Evolution and a few other things, I do recognize its importance in keeping the scales balanced. I value its input because without it we would be even more ignorant than what the powers in charge would like us to be.

Just sayin’…

I see, don’t refute any statements, just attack the messenger. Brilliant. Your credibility? Zero!

How about Shake n’ Bake, another reason to stop the stock-piling of unspent fuel.

Really, “Union of Concerned Scientists”, you mean Mothers for Peace here. Reading behind a “group” bears no credibility for me, not worth reading!


The most dangerous two buildings in California sitting directly on top of a known fault line and they don’t have to pass muster.

What are we supposed to do, pray that an 8.0 doesn’t hit?