A nuclear watchdog group presented arguments Wednesday that operators of the San Onofre power plant improperly avoided a full government review of redesigned generators installed in recent years. Problems with those generators have idled the facility for nearly a year.
The coastal plant, located in northern San Diego County, suffered a radiation leak on Jan. 31 that was traced to a steam-generator tube leak. Further inspections turned up rapid degradation of tubing within generators that were replaced in 2010 and 2011.
Friends of the Earth, an international environmental and nuclear safety group, said the plant operator — Southern California Edison — should have recognized the true risks of several design changes to the generators. It also said Edison violated regulations by not having its plans undergo a more thorough license amendment review by the Nuclear Regulatory Commission.
Instead, the group said, Edison took steps to make sure prior government approval was not needed, starting with contract provisions signed by generator manufacturer Mitsubishi Heavy Industries.
“The licensee (Edison) must determine that the proposed change is safe and effective through appropriate engineering and technical evaluations,” said Arnie Gundersen, a Vermont-based nuclear consultant, on behalf of Friends of the Earth. “That’s not what happened at San Onofre.”
Edison has defended its evaluation of generator design changes. Company spokeswoman Maureen Brown said the generator replacements resulted in changes to some plant specifications that underwent a more thorough, license-amendment review.
The Rosemead-based utility has traced the generator problems to faulty computer modeling of steam velocities in the design phase and some manufacturing issues.
Friends of the Earth attorney Richard Ayers acknowledged the group has limited knowledge of Edison’s evaluation of the generators under so-called “50.59” regulatory provisions for changes, tests and experiments. He said the group has been unable to access the evaluation documents through proceedings or a request under the federal Freedom of Information Act, despite assurance it would protect sensitive or proprietary information from public release.
An Edison representative would not immediately comment on that issue.
Doug Broaddus of the nuclear commission said only Edison maintains documentation of its analysis of the generator design modifications.
“It’s something that the licensee (Edison) has control over,” said Broaddus, chief of the San Onofre special projects branch. “It is something that is reviewed during inspections by our inspectors. … It is not something that has been submitted to us, that we could make available.”
Dan Hirsch, a nuclear activist and lecturer at the University of California Santa Cruz, criticized regulators for putting the burden of proof on Friends of the Earth without providing access to those records.
“It seems to me that your system is completely broken if you allow the licensee (Edison) to make the determination whether or not they have to come to you for a license amendment, and then you keep that secret from the public,” Hirsch told the petition review panel by phone during a public comment session.
Friends of the Earth wants Edison’s operating license to be suspended. A response by a nuclear commission review board in Rockville, Md., is at least two weeks away.
In separate proceedings, Friends of the Earth also is pushing for a more thorough, semi-judicial review of Edison’s proposal to restart San Onofre’s Unit 2 reactor at partial power for five months.
Source: UT San Diego