Senator Boxer requests documents on changes made at San Onofre nuclear plant

A new report claims operating the San Onofre nuclear power plant on reduced power will not solve ongoing problems with steam generators.

The latest report is from a Friends of the Earth-commissioned report produced by Vermont-based Fairewinds Associates. The report also reasserts that modifications made by plant operator Southern California Edison (SCE) has caused damage to generator tubes. Those problems have kept the plant shut down since January 31.

California Senator Barbara Boxer has written federal regulators about the problems. Boxer has requested the Nuclear Regulatory Commission provide the documentation for design changes made to the San Onofre nuclear plant’s generators when they were installed in 2009 and 2010. She also wants to see how the federal regulator reviewed the modifications.

Boxer also wrote a letter to SCE's parent company, Edison International, requesting the same documents.

A report, by Vermont-based Fairewinds Associates and commissioned by Friends of the Earth, claims changes made by SCE are the reason hundreds of steam generator tubes are wearing at an accelerated rate. The group says modifications made by SCE should have gone through a more rigorous review by federal regulators.

SCE and the Nuclear Regulatory Commission refute the claims made in the report.

The report also suggested SCE did not properly notify federal regulators or misled them about design changes. The Nuclear Regulatory Commission and SCE have said those claims are false.

A radioactive steam leak from one of the thousands of tubes inside one of the generators caused the shutdown of one of the plant's two units three months ago.

The other unit was already shut down for scheduled maintenance, but when inspectors looked at that unit, they found the same problems with tubes.

Earlier this month, SCE suggested it could restart the plant at reduced power as a way to ease the vibrations causing the unusual tube wear. Another Fairewinds report, issued this week, says that is not going to solve the problem.

The plant’s four generators each have nearly 10,000 tubes which carry radioactive water. The tubes are one of the primary barriers preventing the release of radioactive steam into the atmosphere, which is what happened last January.

Federal regulators have said there’s no timetable to restart the reactors at the nuclear plant.

In the meantime, a gas-fired power plant in Huntington Beach has been “unretired” as a backup power source should the nuclear plant remain offline during the summer when power demand peaks.

In a statement, Edison officials said the company has provided “open and transparent information to the Nuclear Regulatory Commission” from the steam generator replacement through the ongoing shutdown. The statement said Edison welcomes the opportunity to share information about the San Onofre Nuclear Generating Station with Senator Boxer.

This story has been updated.