Expert: San Onofre's Leak Problems Run Deep

San Onofre could be on ice for 18 months before technicians finally fix the faulty  generators that , according to a report issued Tuesday by Fairewinds Associates, an energy consulting firm hired by an anti-nuclear group.

"The damaged steam generators ... require major modifications with repair and outage time that could last more than 18 months if [Southern California] Edison and [generator manufacturer] Mitsubishi are even able to repair these faulty designed steam generators," the report states.

The report, commissioned by the environmental group Friends of the Earth, said replacing the steam generators is the only real solution to the problem. Written by Arnie Gundersen of Fairewinds, the analysis also suggested slicing off the tops of the current generators so technicians could access the tubes directly, a process that would cost about $400 million.

(See the attached PDF file to view the full report.)

Installing the now-idled generators was a It cost more than $670 million and was finished in 2010.

The components at issue are heat exchange tubes, one of which burst in January and spewed a small amount of super-heated radioactive steam.

When the plant is working properly, water in the reactors is boiled by the nuclear fuel and sent through the tubes at high pressure in a closed loop. The tubes heat non-radioactive water, which boils to create steam that turns turbines and creates electricity.

After the January leak, , and -- an uncommon amount of wear for steam generators only two years old.

Regulators, Edison and previous reports by Fairewinds have determined that the wear .

The Tuesday report said plans to run the plant at reduced power wouldn't remove the danger of leaks or wear caused by vibration -- and could make the problem worse.

Fairewinds also asserts the design of the new steam generators was changed, but that Edison manipulated paperwork so the Nuclear Regulatory Commission wouldn't inspect the design more thoroughly.

"Edison’s strategic goal was to avoid the process of license amendmen," the report alleges. "Had Edison notified the NRC that the new steam generators at San Onofre were not a like-for-like replacement, a more thorough review ... would have been required."

An NRC spokesman, however, told the Associated Press that Edison followed the rules and submitted all its paperwork about the generator design when it was initially up for approval.

During the NRC's investigation of January's leak and tube wear, the Voice of OC reported that a crucial generator design document was missing. Originally submitted as part of the steam generator planning process, the document was released to the press and NRC on Tuesday, after the Friday Voice report.

The document contains no information about the design changes that Fairewinds asserts would have triggered more intensive review, the Voice reports.

Sen. Barbara Boxer Tuesday asked the Nuclear Regulatory Commission and Southern California Edison to provide the documents related to the design changes and documents related to the NRC's review of them, the Associated Press reports.