LOS ANGELES (CBS/AP) — California Sen. Barbara Boxer wants the Justice Department to investigate if the operator of the troubled San Onofre nuclear power plant intentionally misled federal regulators.

The plant between Los Angeles and San Diego hasn’t produced electricity since January 2012, after a small radiation leak led to the discovery of excessive wear on tubes carrying radioactive water.

The Democrat who chairs the Senate Environment and Public Works Committee has uncovered a 2004 internal letter that she says leads her to believe that Southern California Edison deceived the Nuclear Regulatory Commission about design changes to the plant’s steam generators.

Boxer says in a statement Monday she wants the Justice Department to determine if Edison “engaged in willful wrongdoing.”

NRC spokesman Eliot Brenner declined comment.

Edison did not respond to requests for comment.

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