US Nuclear Regulatory Commission

Facility decommissioning could cost billions; Southern California Edison will record a $650-million charge in second quarter.

Southern California Edison (SCE) is closing down its troubled San Onofre Nuclear Generating Station.

The plant’s two reactor units have been shut down since early 2012 after a small leak was detected in a steam generator manufactured by Mitsubishi Heavy Industries.

The Rosemead, Calif.-based utility originally submitted plans to the U.S. Nuclear Regulatory Commission to restart the reactors, but uncertainty about whether the plan would be accepted and the length of time involved during which SCE would need to maintain the plant in a state of readiness led to the decision to retire the plant.

“Looking ahead, we think that our decision to retire the units will eliminate uncertainty and facilitate orderly planning for California’s energy future,” says Ron Litzinger, SCE president, in a statement.

Although the company expects to have adequate power from other sources to meet demand, Litzinger says that generation outages, wildfires or soaring temperatures could test the system.

SCE will record a charge of up to $650 million in the second quarter as a result of the decision, although the utility plans to pursue recovery of damages from Mitsubishi.

Decommissioning is expected to take decades and cost billions of dollars.