The future of the Diablo Canyon nuclear power plant lies at a crucial tipping point. In 2022, the California Legislature passed Senate Bill 846, delaying Diablo’s scheduled closure by five years—provided that certain conditions are met and it could be shown that keeping the plant open is both prudent and cost effective. Will Diablo be able to meet these standards?
Seeking to determine that, Sen. John Laird asked the California Senate Energy, Utilities, and Communications Committee’s August 2025 panel of PG&E executives and energy agency heads about an apparent $300 million shortfall in the expected repayment of a $1.4 billion forgivable state loan to PG&E to keep Diablo Canyon open. PG&E was only awarded $1.1 billion from the federal grant intended to repay its $1.4 billion state loan. So Laird asked two state agency representatives, “What’s on the bottom line to make sure that [PG&E’s full loan repayment is] actually happening?”
Laird eventually received an answer: There is “no guarantee” that the missing $300 million difference won’t come from our deficit-riddled state budget and overburdened California taxpayers.
(Since an additional $359 million from the $1.1 billion federal grant was “conditional” and not guaranteed, the next Senate oversight hearing should ask PG&E if California taxpayers could be left holding the bag for a total of $659 million.)
Sen. Laird asked about seismic safety studies, and the PG&E representative replied that the Diablo Canyon Independent Safety Committee has reviewed PG&E’s latest seismic study and “deemed Diablo seismically safe, and there are no additional requirements or modifications needed at the plant.”
However, the seismic safety report is not complete yet, so this conclusion is premature. Per the Alliance for Nuclear Responsibility, the Diablo Canyon Independent Peer Review Panel (IPRP) is still drafting its final evaluation of the seismic studies. A seismic safety review that does not incorporate the IPRP’s evaluation and recommendations, as required by SB 846, is by definition incomplete.
Therefore, the next Senate oversight hearing should ask the IPRP for its evaluation and recommendations and ensure that its feedback is incorporated, prior to making any final conclusions.
Sen. Laird also asked about the ongoing practice of storing Diablo’s spent fuel rods in pools despite the common misconception that all Diablo’s current and future spent fuel will be transferred to concrete casks. The PG&E rep replied that there was no difference in safety between the two methods of storing nuclear waste.
“If I had more time, I would pursue that,” Laird replied.
In the hearing’s most surreal moment, Laird asked the PG&E rep about the reactor vessel test they agreed to perform due to potentially defective welds and embrittlement of the vessel. The test will not be completed until April 2026. However, well before that date, the PG&E rep made a premature assumption about the reactor vessel safety by saying, “the capsule that we pulled from Unit One … is going to be used as a re-verification, confirmation of already determined [sic] that Diablo Canyon reactor vessels are safe for 60 years.”
“If I had more time, I would explore that more,” Laird replied, also observing that “it seems premature to declare that everything’s great, and then there’s one piece of it that’s still being tested.”
Clearly this issue needs a dedicated hearing so the topic can receive the time it requires to address questions and any inconsistencies.
The August hearing alone should not be deemed the final word on this matter. It lacked ratepayer and other non-agency experts on energy demand and reliability who could deliver real-time fact-checks and clarify the jargon and spin that tended to flow over the dais.
Separate hearings of the Senate Energy and Budget committees are needed to address all the issues around Diablo’s continued operation. Do we still need the energy that Diablo Canyon generates despite the state’s massive gains in renewable energy over the last five years? Can we afford what it costs? (And what exactly is that cost?) And in answering both those questions, can we see a direct comparison between the cost of the energy generated by the nuclear plant and the cost of energy generated by California’s renewable resources and battery storage?
Sen. Laird is asking the tough questions we need answered. However, he also needs to have the time and additional expertise in the room to drill down and get real answers to questions about Diablo’s safety, necessity, and affordability, starting with the first question Laird asked at the August hearing: “Where are we on replacing Diablo?” ∆
Gianna Patchen is chapter coordinator for the Santa Lucia Chapter of the Sierra Club. Andrew Christie served as chapter director from 2004 to 2023. Send a letter for publication to letters@newtimesslo.com.
This article appears in Student Guide 2025.
The ratepayers and taxpayers need real answers to Senator Laird’s questions, answers filled with hard data and facts. The questions remain. When will we get the answers?
I thank Gianna and Andrew for their well-informed article showing the absurdity of extending the operation of Diablo Canyon nuclear plant. It’s costly and poses great potential harm: seismic risk; aging systems and components; storage of even more high-level radioactive waste (in an active seismic area); damage to the marine environment due to the once-through cooling system; and oversight by the Nuclear Regulatory Commission has been severely curtailed by the current administration. Shut it down NOW!
Thank you Gianna Patchen and Andrew Christie for this excellent article, and also thank you to Senator John Laird for his questions to PG&E.
The responses from the PG&E Rep were incomplete, vague and lacking at best. And from those response, it makes it more clear that Diablo Canyon Nuclear Power Plant needs to be shut down ASAP!
PG&E and certain people who support them and the people who enable the nuclear-industry-captured NRC are not telling the truth or have come to believe there own falsehoods and rationalizations regarding the dangerous technology called nuclear power. They will support Diablo Canyon as long as they can make a buck out of it, and are the first to duck and run to avoid Diablo’s negative consequences, leaving ratepayers with the mess they have already created.
It is up to us, brave and determined friends, to close down down a facility that should never have been built. Shut it down! We can conserve and use less energy. We have the warm power of the sun.