NRC Probing Edison Unit’s Documents on Nuclear Plant

The U.S. Nuclear Regulatory Commission is investigating information that an Edison International unit provided to the agency about two shuttered reactors at the company’s San Onofre plant in California.

The probe, which began Sept. 28, is looking into the “completeness and accuracy” of information from Southern California Edison regarding steam generators at the plant, agency Chairman Allison Macfarlane said yesterday in a letter to Senator Barbara Boxer, a California Democrat. Boxer’s office released the letter.

“This investigation is a critical factor in determining whether it is safe to restart the San Onofre reactor’s Units 2 and 3,” Boxer said in a statement.

The San Onofre plant’s two reactors have been out of service since January 2012, after investigators found unusual wear on steam generator tubes. Boxer, chairman of the Senate’s environment and public works committee, and Representative Edward Markey of Massachusetts, the top Democrat on the House’s natural resources panel, have said the plant should stay closed until the NRC ensures that it can operate safely.

The lawmakers asked Macfarlane on Feb. 6 to investigate whether the utility and the supplier of the tubes, Tokyo-based Mitsubishi Heavy Industries Ltd., knew about problems with the equipment’s design before it was installed. They cited a Mitsubishi report that has not been publicly released.

Macfarlane said in her letter yesterday that the NRC is also examining the report.

Southern California Edison “takes very seriously all requests from the NRC related to the operation of the station,” Jennifer Manfre, a company spokeswoman, said in a statement. “The plant has provided voluminous records, data information and other accurate reports as requested in the months since the plant was safely shut down.”

Manfre said the Rosemead, California-based company “will continue to provide any and all relevant, factual material requested by the NRC and provide any clarifications necessary.”