Time to Close Diablo

Nuclear Power Unsafe and Unnecessary for California's Energy Needs

Diablo Canyon Nuclear Power Plant

Wed Jul 19, 2023 | 09:00pm

Today, the Central Coast is faced with a 20-year extension of operations at Diablo Canyon nuclear power plant, in Avila Beach. This is being made possible by a rushed and chaotic governmental approval process that is happening now.

We at San Luis Obispo Mothers for Peace are doing everything we can to show regulators and the public why an extension of Diablo’s license is exactly the wrong thing to do when California needs to accelerate moving to a safe, reliable, all-renewable energy portfolio.

This is what you need to know:

Diablo Canyon’s two nuclear reactors were scheduled to shut down in 2024 and 2025, at the end of their full, 40-year operating life. That was until Governor Newsom was persuaded (by whom? and why?) that California needed the power from Diablo to avoid summer blackouts. Newsom then pushed the California Legislature, in the fall of 2022, to make possible a five-year extension for Diablo through 2030.

For that to happen, a number of California agencies will need to provide permits and licenses as soon as the end of this year.

Pacific Gas and Electric (PG&E), Diablo’s owner, must also get an extension from the U.S. Nuclear Regulatory Commission (NRC). Interestingly, PG&E isn’t asking for a five-year extension. Instead, the corporation is asking for what it says is the NRC’s standard, 20-year renewal. We are deeply concerned that this extension will be granted, since the NRC has never denied a license renewal to any applicant. And armed with that, wouldn’t PG&E immediately start leaning on the state to extend beyond 2030?

In fact, no extension is necessary. Mothers for Peace and numerous environmental groups and energy experts agree that continued power generation at Diablo is not needed in the projected time frame. The plant’s continued operation obstructs the development of other, actual, renewable sources and takes distribution space on the energy grid that is needed right now by renewables.

The approval processes going on at state and federal levels require extensive review of all of the safety risks at this aging plant. That includes the earthquake danger (two of the 13 identified fault lines nearby are considered by the U.S. Geological Survey to be “active” and “major”), the significant embrittlement danger within the reactor vessel of Unit 1, the intractable problem of 6 million pounds of radioactive nuclear waste in storage at the site, and at the most basic level, all of the upkeep of this nuclear facility that was put on hold when it looked like the plant was going to shut on schedule.

All of these safety issues, and the expenses associated with handling them, need to be addressed if permit-issuing agencies are to make informed decisions. Will these agencies get the full information they need? Will it be available by the impossibly tight deadlines in play? Or will there be shortcuts? Will there be pressure to just push this through and worry about the details later?

Mothers for Peace is approaching these critical issues in two ways: We petitioned the NRC to deny PG&E’s license extension on the basis of its violation of the “timely renewal” clause in its own regulations. The NRC denied our petition, and we have filed an appeal in the 9th Circuit Court.

Our second approach is with the California Public Utilities Commission (CPUC), which will make a crucial decision on whether or not the costs of extending are worth it to all of the rate payers (not just PG&E customers) and taxpayers of California. That decision is expected before the end of the year. Mothers for Peace has engaged expert witnesses on seismicity, materials engineering, and renewable energy to address the fundamental issue: why it is not in any way prudent to extend Diablo Canyon’s operating license. In our filings with the CPUC, we have challenged both the need for Diablo’s power and the outrageous costs of refurbishing the nuclear plant and all of its parts to meet safety standards necessary to protect our nearby communities.

Protecting communities near and far was definitely on the mind of the former Prime Minister of Japan Naoto Kan when he wrote to Governor Newsom on May 12, 2022. Mr. Kan was Prime Minister when the Fukushima nuclear reactor meltdown occurred in 2011. When he learned that Newsom was considering extending the operation of Diablo Canyon, he felt compelled to contact the governor. He wrote that until the Fukushima accident occurred, he had never thought that such a meltdown could happen. He added, “Based on my experiences dealing with that disaster, I advise you to shut down the nuclear plant as soon as possible.”

Please, it’s not too late to heed that warning, Governor Newsom.


We all need to speak up. Time is short, but if you find the possibility of an extension extremely alarming, decision-makers need to hear from you. The CPUC will hold a virtual Public Participation Hearing, on Tuesday, July 25. This will be an important opportunity for the public to weigh in. Use this link for more information: cpuc.ca.gov/pph/.


San Luis Obispo Mothers for Peace is a nonprofit group that has been engaged as a Legal Intervenor in all matters concerning safety at the Diablo Canyon nuclear plant since 1973. Here’s our website: https://mothersforpeace.org. Please click on “latest news” to see what we’ve been doing over the past several months, and contact us if you have questions about Diablo Canyon.


Linda Seeley is vice-president and spokesperson for San Luis Obispo Mothers for Peace.

More like this

Exit mobile version