Diablo Canyon Nuclear Power Plant, San Luis Obispo County, CA. Photo: Diablo Canyon Decommissioning Panel.
Environmental groups concerned about cost and safety issues at the Diablo Canyon nuclear plant in San Luis Obispo County on California’s central coast thought they’d scored a big win in 2018 when a Joint Proposal was approved by the California Public Utilities Commission (CPUC) to retire the aging plant by 2025. But like a zombie, Diablo Canyon’s operating life was resurrected until at least 2030 this past summer when California Governor Gavin Newsom rammed a last-minute bill through the California legislature to keep the plant going.
Michael Peck – Diablo Canyon’s senior resident safety inspector from 2007-2012 – tells me the plant should’ve been shut down years ago due to a faulty licensing process that disregarded crucial seismic data indicating the plant is vulnerable to a Fukushima type of nightmare.
Japan’s Fukushima nuclear plant suffered a catastrophic triple meltdown and radiation release in 2011 when a magnitude 9.0 earthquake triggered a tsunami that topped protective sea walls and overwhelmed the reactors. 150,000 people were evacuated as radioactivity spewed into the air and ocean. The catastrophe – deemed a man-made disaster due to regulatory collusion – was the direct cause of nearly 4,000 deaths and remains an ongoing calamity; disposal of vast quantities of radioactive wastewater stored onsite remains an intractable problem.
More than 170 organizations objected to using federal subsidies to delay the closure of Diablo Canyon, which opened in 1984-85. But that didn’t stop the Department of Energy from recently awarding California a $1.1 billion subsidy to resuscitate Diablo Canyon. The writing was on the wall in the spring when Newsom voiced “worst case scenario” concerns about rolling blackouts that put Diablo Canyon back “on the table as an option”. Senator Dianne Feinstein followed with a predictably like-minded editorial in the Sacramento Bee, claiming California wasn’t yet ready to achieve its renewable energy goals as planned.
Mainstream media coverage of Diablo Canyon’s operating extension in 2022 has largely glossed over questions about the plant’s ability to withstand strong earthquakes. But with Newsom and allies in the nuclear industry reaching to extend the aging nuclear plant’s life, the seismic safety issues warrant renewed scrutiny.
Concern about seismic threats to the plant arose even before construction was completed in 1973. Originally designed to withstand a quake of magnitude 6.75, Diablo was discovered in 1971 to be just a few miles from the underwater Hosgri Fault. It was upgraded to allegedly withstand a 7.5 quake (the 1906 San Francisco earthquake registered at 7.8). Then came the 2008 discovery of the Shoreline Fault, just 2,000 feet from the reactors, which further complicated the seismic debate.
Michael Peck’s objections regarding how the NRC and PG&E fudged the license amendment process in 2012 to get around the newly identified seismic issues were the subject of a story by this reporter in 2015. Now retired, Peck remains dismayed at the “circular logic” which he says the NRC used to overrule his report that dissented on how the newly identified fault lines were addressed.
“My issue was with PG&E’s failure to… preserve engineering margins. Federal Regulation required PG&E to apply for and the NRC to approve an Amendment to their Operating License based upon the new seismic analysis, but… NRC’s Diablo Canyon project manager directed PG&E to change their license without the Amendment,” Peck explains.
Peck claims the licensing amendment violation wasn’t just reckless, but that it was criminal. He points to a 2012 letter from NRC’s Diablo Canyon project manager Joseph Sebrosky to PG&E Senior VP & Chief Nuclear Officer Edward Halpin as “a smoking gun.” Peck says it reveals how NRC’s Sebrosky directed PG&E to use a methodology that had been rejected in 2011, in order to get around the new seismic data with regulatory language Peck compares to “a shell game”.
“These are all rhetoric games that PG&E used and that the NRC bought into in order to justify continued operation outside the design basis,” Peck says. “PG&E and NRC failed to use legally binding requirements to amend the Operating License with these new methodologies…I suspect this path was chosen because outside experts and NRC technical reviewers would not agree with PG&E and NRC management’s conclusions. Which, in accordance with the existing Operating License, would require the plant to shut down.”
In 2013, Dave Lochbaum, then-Director of Nuclear Safety at the Union of Concerned Scientists took Peck’s dissent into account in his professional analysis: “The NRC is betting that the big one won’t make Diablo Canyon the next nuclear nightmare. When the stakes involve tens of thousands of Californians, the NRC should stop wagering and resume regulating.” Lochbaum calculated a 1 in 6 chance – “a toss of a die” – that a quake stronger than the reactors are designed for would occur in Diablo’s lifetime.
Nuclear policy expert Daniel Hirsch also highlighted Peck’s concerns in his testimony before an oversight hearing of the U.S. Senate’s Committee on Environment and Public Works, chaired by Senator Barbara Boxer at the end of 2014: “The problem is that nature may not go along with the regulatory fictions… As at Fukushima, an earthquake larger than the plant can withstand could occur at any moment. And as at Fukushima, it will not be an act of nature, but a man-made disaster, caused by the failure of our institutions.”
Peck outlined his concerns in a detailed letter to Boxer in 2015, who then pressured the NRC on multiple issues at Diablo Canyon. The NRC’s Inspector General opened an investigation, for which Peck was interviewed multiple times. I recently used FOIA to liberate the NRC OIG’s report on that investigation. The report concluded that there was no regulatory collusion between NRC and PG&E, but Peck says it’s filled with holes and red herrings.
One of the report’s most egregious fallacies is the claim from NRC’s then-Executive Director for OperationsMark Satorius that Peck told him “he was not raising a safety issue, ”but rather only a “regulatory compliance matter.” Peck says he only agreed that his dissent wasn’t over an “immediate safety issue”, not that he had no safety concerns at all. Another big hole in the NRC’s decision to close the investigation was the reasoning that “NRC individuals involved are no longer employed by the federal government,” as if that was a logical rationale for failure to consider a potentially catastrophic safety risk at a nuclear power plant in a state with a population of almost 40 million!
“In my 28 years as a senior nuclear inspector, I’ve never seen such a disregard for nuclear safety requirements as I saw at Diablo Canyon,” Peck laments.
Then there’s nuclear engineer Arnie Gundersen of Fairewinds Associates, who says the danger at Diablo Canyon is even worse than Peck thinks. He testified to CPUC in 2017, arguing the plant should be closed ASAP because it likely wouldn’t even survive the 7.5 quake that the NRC says it could, much less the stronger one that worries Peck.
Friends of the Earth (FOE) found the seismic concerns alarming enough to file a legal action against the NRC over the lack of public hearings required with the amending of Diablo Canyon’s license. But the organization dropped its litigation in 2018 as part of the deal that was reached to close Diablo Canyon. FOE is now weighing its legal options again.
“I am deeply worried about whether we are looking at this extension underneath the context that this reactor could be operating for another 20 years,” FOE President Erich Pica explained in a recent interview. “We just saw the governor of California tear through a fairly solid agreement, he just politically muscled his way around it. So, there are no guarantees – now that he’s been able to pick Pandora’s Box – that the next governor or next operator of PG&E wouldn’t want to continue operating that reactor. The deep fear I have is that we could get stuck in these five-year incremental renewals that don’t look at the entire lifecycle of the reactor.”
In extending Diablo Canyon’s lifetime to give himself political cover from “worst case scenario” blackouts, Gov. Newsom is putting his faith in PG&E and NRC to acknowledge seismic issues that would cost hundreds of millions of dollars or more to remedy. Is this the same Gavin Newsom who ripped PG&E in 2019 for the utility’s greed and mismanagement following two years of wildfires and rolling blackouts? Is he now willing to gamble that this same utility will value safety over profits at Diablo Canyon? PG&E’s sordid history suggests that’s a dangerous bet.