No study of quakes in Diablo Canyon review

Federal officials to look at plant’s effect on the environment

To many critics of the Diablo Canyon nuclear plant on California’s quake-prone Central Coast, no environmental question is more important than whether the facility can survive shaking from nearby faults.

But as federal officials weigh whether to keep Diablo open for another 30 years, their environmental review won’t delve into that question. Even if the plant’s neighbors want it to.

Instead, the review from the Nuclear Regulatory Commission will focus on how renewing Diablo’s operating licenses would affect the local environment, not on how how the environment may affect the plant.

The commission insists that it constantly monitors Diablo’s seismic safety and doesn’t need to duplicate those efforts. The plant near San Luis Obispo is nearly surrounded by fault lines that were discovered only after construction began in 1968.

“Seismic safety — that’s something that is looked at on a continuous basis,” said Michael Wentzel, the commission official in charge of the environment review. “That’s not an issue

for 10 years from now. That’s an issue right now.”

The plant’s opponents, however, say the commission’s review is ignoring the most pressing question raised by the possibility of extending Diablo’s licenses, which are set to expire in 2024 and 2025.

“It’s foolish to tell Californians that they won’t consider the most controversial issue at the last nuclear plant in the state,” said Rochelle Becker, director of the Alliance for Nuclear Responsibility.

Diablo’s owner, Pacific Gas and Electric Co., applied in 2009 to renew the plant’s licenses but put that effort on hold following the 2011 Fukushima nuclear plant meltdown in Japan. The commission, however, recently announced it would restart the relicensing process, saying its staff would need plenty of time to conduct reviews.

PG&E has not yet decided whether to push ahead with securing all the necessary California permits for extending Diablo's operations.

PG&E this spring released its latest seismic analysis showing that the plant was capable of surviving the strongest earthquake likely to hit in 10,000 years. Critics, however, have long accused the company of tweaking its seismic studies to minimize potential dangers. They want earthquake safety to be one of the main considerations for renewing Diablo’s licenses and say it needs to be part of the environmental review.

The mismatch between public expectations and federal procedures surfaced this month when the commission held two public hearings in San Luis Obispo. The hearings were intended to give the plant’s neighbors input into the relicensing effort’s environmental review, suggesting topics that the review should cover.

Time and again, Diablo’s opponents questioned the plant’s seismic safety. They seemed stunned when Wentzel said the review would not study that issue.

“There were a lot of people thinking, ‘You’ve got to be kidding,’ ” Becker said.

Wentzle said seismic hazards do play a role in the environmental review, and in a separate study that evaluates the state of the plant’s structures and equipment. In the environmental review, seismic threats will form the basis of a section that looks at “severe accident mitigation alternatives” — steps that PG&E can take to protect the environment in case of a serious accident at the plant.

But neither the environmental review nor the equipment safety study will address whether Diablo can survive shaking from nearby faults.

“We’re not going to look at what kind of seismic hazard the plant can withstand,” Wentzel said in an interview. “Those issues are looked at as part of our day-today oversight of the plant. That’s actively going on, but that process is separate from license renewal.”