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San Onofre closure: Federal regulators defend SoCal Edison

An aerial shot shows the San Onofre nuclear power plant in this undated file photo.

July 19, 2012 12:00:00 AM PDT
Federal regulators have stepped up to defend the operator of the San Onofre nuclear power plant.

In a new report, investigators say Southern California Edison didn't try and mislead the government about the cause of the plant's problems.

Regulators say a faulty computer study led to steam generator breakdowns and tube damage that forced officials to shut San Onofre down in January.

Environmental activists have suggested that Edison duped the government about changes it made prior to the shutdown.

It's not known when the plant will be back on line.