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Edison seeks to fire up San Onofre nuclear reactor

Mark Ralston / AFP - Getty Images

A view of the San Onofre Nuclear Power Plant in north San Diego County is seen in this March 2011 file photo.

The operator of California's troubled San Onofre nuclear power plant proposed Thursday to restart one of the plant's shuttered  reactors, despite an outcry from activists who say doing so could be catastrophic.

Southern California Edison filed the proposal with the Nuclear Regulatory Commission after concluding a reactor could be operated safely despite damage to scores of its tubes that carry radioactive water.

A plan to return even one reactor to service is a milestone for Southern California Edison, which has spent months unraveling what caused excessive tube vibration and friction inside the plant's nearly new steam generators, then determining how it might be fixed.

But the plant is far from returning to robust operation.

Edison must wait for approval from U.S. nuclear regulators before restarting the unit. Nuclear regulators say there's no timetable to restart the plant, and review of the application could take months. "The agency will not permit a restart unless and until we can conclude the reactor can be operated safely," NRC Chairman Allison Macfarlane told Reuters. "Our inspections and review will be painstaking, thorough and will not be rushed."

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The proposal was immediately denounced by environmentalists and anti-nuclear activists who have argued for months that restarting the plant between San Diego and Los Angeles would set the stage for a catastrophe. About 7.4 million Californians live within 50 miles of San Onofre, which can power 1.4 million homes.

"Both these reactors are alike, and neither is safe to operate," said S. David Freeman, a former head of the Los Angeles Department of Water and Power who advises Friends of the Earth. "While Edison may be under financial pressure to get one up and running, operating this badly damaged reactor at reduced power without fixing or replacing these leaky generators is like driving a car with worn-out brakes."

Edison wants to operate Unit 2 at 70 percent power, which company officials predicted would prevent vibration that has caused excessive wear to tubing. Company officials expressed confidence in the proposal, which followed more than 170,000 tube inspections over more than eight months.

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In January, the Unit 3 reactor was shut down as a precaution after a tube leak. Unit 2 was taken offline earlier that month. Neither unit has been operational since. The plant's Unit 1 was shut down permanently in 1992.

Federal regulators examined the plant to determine what happened to Unit 3 and how it could have been prevented. While the Nuclear Regulatory Commission commended the staff for their handling of the leak, they expressed concern over the design flaw that caused it.

Southern California Edison also pointed to the high costs of running the plant as a reason for downsizing its staff. Compared to similar plants, the staffing and costs are much higher. The company will also reduce costs by “improving plant processes while fully maintaining all safety commitments,” they stated in August.

This article includes reporting by NBCLosAngeles.com's Lauren Steussy and Reuters.

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