Environmental groups demand shutdown of Diablo Canyon reactor

September 18, 2023

Diablo Canyon Nuclear Power Plant

Statement from Mothers for Peace and Friends of the Earth

The environmental advocacy groups Mothers for Peace and Friends of the Earth have jointly filed a petition calling on NRC commissioners to order the immediate shutdown of Diablo Canyon Unit 1 for tests and inspections of its pressure vessel that have been delayed for twenty years.

The pressure vessel may be the most important component of the reactor because it encases water on the highly radioactive reactor core. Failure of the reactor vessel could cause a catastrophic meltdown.

That risk is increased by Diablo Canyon’s proximity to a web of earthquake faults if vessel failure were to occur coincidently with a major earthquake that might breach containment. Yet, Pacific Gas and Electric Co. (PG&E) has repeatedly postponed essential metallurgical tests and ultrasound inspections over the past two decades.

The last inspections of the Unit 1 pressure vessel were conducted in 2003-2005. Alarmingly, despite serious indications of embrittlement, PG&E declared key test results “not credible.” They postponed further testing, claiming that the results from tests on what are called “sister” reactors —  those of similar design and materials and that have similar operating characteristics (e.g., maximum operating power, temperature, etc.) — were sufficient to justify continued operation.

Dr. Digby Macdonald, UC Berkeley Professor in Residence, Departments of Nuclear Engineering and Materials Science and Engineering, retained by the groups to evaluate the status of Unit 1, argues in his petition that the Charpy impact fracture test results conducted in 2003-2005 were credible and should have caused PG&E to inquire further rather than postpone the next scheduled inspections.

He dismissed PG&E’s decades-long reliance on data from similar pressure vessels, saying that “even if two nuclear plants are identical in every respect (“sister” nuclear reactors never are), each soon becomes individualized by unique operating conditions and histories.”

Macdonald also pointed out that PG&E was already warned that Unit 1 should be closely watched, given the discovery during reactor construction of defects due to excessive copper and nickel content. These defects “require more, not less, testing,” he said.

“Now we are at a watershed moment where the safety risks created by PG&E’s failure to conduct any surveillance of capsules from the Unit 1 pressure vessels or ultrasound testing of the pressure vessel’s beltline welds are extremely grave,” Macdonald added.

Diane Curran, attorney for Mothers for Peace, said the groups’ extensive investigation had  revealed an unprecedented and persistent pattern of neglect by PG&E and the NRC technical staff of their regulatory responsibilities for the condition of the Unit 1 pressure vessel.”

Curran underscored that the groups were appealing to the Commissioners, as the top officials in the agency, to take charge of the situation, reverse the regulatory lapse of the technical staff, and ensure that the required tests and inspections are conducted immediately. Additionally, Curran asserted that Unit 1 must be shut down immediately and remain closed until PG&E and the NRC technical staff had thoroughly evaluated the condition of the Unit 1 pressure vessel and justified continued operation in a public hearing.

Hallie Templeton, Legal Director for Friends of the Earth, said, “This petition is part of a comprehensive legal strategy to ensure that people and the planet are not put at risk of a nuclear meltdown while PG&E profits in the billions. We will not sit idly by while PG&E cuts corners on Unit 1’s safety and the NRC rubber stamps operation with a dangerously deteriorating pressure vessel.”

Linda Seeley, spokesperson for Mothers for Peace, denounced the NRC’s lack of oversight and transparency over the past decade, leaving San Luis Obispo residents unaware of lurking safety risks. She warned, “The California State legislature, which decided a year ago to extend the operation of Diablo Canyon, should be worried that the federal government agency on which they are relying for the safety of the plant has been complicit in a very serious safety lapse.”

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I’m fine with closing Diablo Canyon just as soon as the NRC authorizes the construction of two small, modern reactors to replace it so we aren’t thrown back into the dark ages by the panties-in-a-twist mob and their yes-clowns in SACTO.

Just remember, even after a retrofit, the Diablocanyon nuclear power plant is only rated to withstand up to a 6.8 earthquake. That’s the fact that a lot of people don’t want you to know. The plants ocean water cooling system is also extremely vulnerable to tsunami‘s.

More money will be brought into San Luis Obispo County to pay for the decommissioning, then will be generated during the same amount of time if the plant operates.

Interesting to note how PG&E is trying to shift liability responsibilities onto the government and the public taxpayers

Hey great news – it will be shutdown in about a week

Better news – it’ll be restarted in about a month

I demand they give up cable and power and natural gas for their homes….

Interesting accusations about Unit 1 pressure vessel, needs to be checked out by the NRC. Good story

How come the Friends of the Earth aren’t demanding that grizzly bears be re-introduced to Los Osos….you know, “the valley of the Bears”? Come on! Let’s embrace Chumash indigenous wisdom & cultural heritage to restore the unique dune and estuarine environment of Los Osos/Baywood to what it once was before being trampled and over-populated with Los Angeles leftist loons. Think how much the bears will thrive in addition to all the electrical energy that would be saved!

Bears and Chumash generally don’t present an existential threat to an entire area as does Diablo, which is situated over the San Andreas fault. Do some research on Fukushima if you don’t think what happened to the Japanese could happen to us.

Perhaps if you did some research, you would learn that Diablo Canyon is not situated over the San Andreas Fault, nor does it represent an existential threat to our area, and, finally, any tsunami big enough to do to Diablo Canyon what happened at Fukushima would have to be so freakishly massive that it would also devastate all or vast tracts of every one of our coastal cities in the county. Most of the power plants vital infrastructure (emergency generators & fuel, batteries, cooling water reservoirs, etc.) are situated 85 feet above sea level or higher. What have you done to prepare our coastal communities for an 85 foot high tsunami?

I said it before and I will repeat it here. Many of these groups will not be happy until we are in a real life episode of naked and afraid. We will be given our machete and two sticks and sent out into the wilderness to be one with the earth!

I’m a taxpaying CITIZEN and demand they keep the power plant open! We all use electric power and there’s NOTHING to replace it!

Hold the phones! Stop the presses! We have a CITIZEN, but not just any citizen, a gosh darn taxpaying (!!!) citizen.

Might be “friends of the earth”… but not friends of the people who live in it.