NRC could alter rules for San Onofre restart

The twin reactors between Los Angeles and San Diego haven't produced electricity since January 2012, when a tiny radiation leak led to the discovery of damage to hundreds of tubes that carry radioactive water.

The Nuclear Regulatory Commission last year outlined a series of steps operator Southern California Edison must take before a restart would be allowed, including determining how to stop damage to tubes in the plant's steam generators. Edison last fall year submitted a plan to restart one reactor and run it at reduced power in an effort to halt tube erosion.

But NRC Deputy Regional Administrator Art Howell said in a hearing in Dana Point the agency is considering changing those requirements "as needed." He didn't elaborate.

Meanwhile, the NRC announced it was preparing a fresh round of technical questions for the company about its restart proposal.

Edison spokeswoman Jennifer Manfre said in an email the company "will continue to respond to all questions and requests for information throughout this entire, thorough process."

Last year, federal officials blamed a botched computer analysis for design flaws that they said are largely to blame for unprecedented wear in tubes at the plant. They found a computer analysis by Mitsubishi Heavy Industries, which manufactured the generators, vastly misjudged how water and steam would flow in the reactors.