Review of plan to restart San Onofre reactor could take months

The darkened San Onofre power plant will not restart even one of its two reactors for months, the head of the U.S. Nuclear Regulatory Commission said Wednesday.

In the meantime, anti-nuclear advocates stepped up pressure to keep the plant shut down, with the release of an analysis showing the issues with San Onofre’s steam generators are among the worst in the industry.

The plant has been shuttered since Jan. 31, when a tube in one of the plant’s newly replaced steam generators leaked, releasing a small amount of radioactive steam, and leading to the discovery that hundreds of other tubes were wearing out more rapidly than expected.

NRC Chairwoman Allison Macfarlane said at a U.S. Senate committee hearing on nuclear safety that Southern California Edison, the operator of the troubled nuclear plant, has told the agency it plans to submit an analysis of the problems and a restart plan for one of the plant’s two reactors, Unit 2, by the end of the first week in October.

Once that happens, she said, NRC staff will review the plan in a process that “will be longer than days and weeks — it will be on the order of months.”

Edison has no immediate plans to submit a restart plan for the second reactor, Unit 3, which had more tubes with damage overall and more of a particularly unusual type of damage caused by tubes rubbing against other tubes.

The company has said that unit may not be able to fire up again without extensive repairs and has announced plans to remove fuel from the reactor.

Sen. Barbara Boxer drilled NRC commissioners at the hearing on their plans for San Onofre and suggested making regulatory changes that would require more extensive review of future projects, such as the costly steam generator replacement.

An initial NRC review of the issues blamed faulty computer modeling by steam generator manufacturer Mitsubishi Heavy Industries for the problems, but some have argued that the problems could have been avoided if design changes in the new steam generators had received a full NRC review.

NRC officials have said that Edison informed them of the design changes, but the company was not required to go through a license amendment process.

Also Wednesday, the anti-nuclear group Committee to Bridge the Gap released a report with data compiled from steam generator tube inspection reports submitted to the NRC by all nuclear plants with similar replacement steam generators. The NRC does not compile the tube wear data in a central location, and the Electric Power Research Institute, which maintains a database of information reported by the utilities, says their data is proprietary.

“The conclusion is clear: San Onofre Unit 2 and Unit 3 are both very ill nuclear plants.... They are far, far outside the norm of national experience. And Unit 2 cannot be said to be acceptable for restart, any more than Unit 3,” the report’s authors wrote.

NRC spokesman Victor Dricks said the agency had not had a chance to review the report Wednesday.

Edison spokeswoman Jennifer Manfre said the company had not been able to review the data in the report for accuracy but called its presentation of the information misleading.

abby.sewell@latimes.com