Senator Barbara Boxer wants the U.S. Justice Department to investigate Southern California Edison and its statements to federal regulators about swapping out generators at the San Onofre Nuclear Power Plant.
Three months after asking the Nuclear Regulatory Commission to look into the shutdown of the plant located north of Oceanside, Boxer announced she wants federal and state officials to investigate whether the utility company "engaged in willful wrongdoing."
The new request for a criminal probe centers on a 2004 letter written by a senior Southern California Edison (SCE) executive to Mitsubishi Heavy Industries, manufacturers of the generators.
The San Onofre plant's power generators -- Unit 2 and Unit 3 -- were deactivated in January 2012. Unit 2 was taken off-line for planned maintenance. Unit 3 was shut down after a leak was detected in one of its steam generator tubes.
The small radiation leak led to the discovery of unusually rapid wear inside hundreds of tubes that carry radioactive water in the nearly new generators.
Edison replaced $670 million worth of new generators in 2009 and 2010 without any review because it met a federal test of being largely the same parts.
But the Nov. 30, 2004 letter from SCE Vice President Dwight E. Nunn states that "although the old and new steam generators will be similar in many respects they aren't like-for-like replacements."
Boxer said the letter "leads me to believe that Edison intentionally misled the public and regulators" to avoid a potentially long and costly review of four replacement steam generators before they went into service.
On Monday, SCE said the differences were insufficient and the letter was meant to be a precautionary letter of what was expected of Mitsubishi Heavy Industries.
"SCE would never, and did not, install steam generators that it believed would impact public safety or impair reliability," said Pete Dietrich, SCE senior vice president and chief nuclear officer.
Nuclear Regulatory Commission spokesman Eliot Brenner declined comment.
The plant, located north of Oceanside, has been shut down since January 2012. Before it was closed, San Onofre produced enough power for 1.4 million homes. Costs for the long-running shutdown have topped $553 million according to the Associated Press.
SCE is seeking federal permission to restart the Unit 2 reactor and run it at reduced power in an effort to halt tube damage.