Southern California Edison announced Thursday that it plans to restart the San Onofre Nuclear Generating Station’s reactors in June, four months after extremely rapid tube wear caused a minor radiation leak.
The company also acknowledged for the first time that design problems might have ultimately caused January’s small radioactive release.
Southern California Edison plans to run the reactors at up to 80 percent power for several months before re-examining them. The utility says its plan would ensure that tube vibration, the ultimate cause of January’s leak, would not take place.
The proposal drew a swift rebuke from environmental advocates, who have argued that restarting the reactor would put the public at risk because the vibration and leak were caused by underlying design flaws.
An outside nuclear expert, hired by an environmental group, has concluded that three key design changes made to replacement steam generators were responsible for the tube wear.
After weeks of not commenting specifically on the leak's cause, the utility now acknowledges that design problems are likely at fault.
“We are thinking that this is probably a design defect,” Edison vice president Stephen Pickett told U-T San Diego. He added that shipping, installation and operation of the generators have been ruled out as causes.
Arnie Gundersen, the outside expert, has also alleged that Edison misled the federal government about the changes to avoid a thorough independent review of their safety risks.
When applying to install the replacement generators, which were brought online in 2010 and 2011, Edison asserted that the design changes posed no additional safety risk, according to the U.S. Nuclear Regulatory Commission.
Edison insists it was completely open about the design changes.
“We notified them of all changes,” utility spokeswoman Jennifer Manfre said in early April.
After several requests, however, both the NRC and Edison have yet to state whether regulators reviewed and approved the three changes cited by Gundersen.
Edison has promised not to restart San Onofre until the leak’s ultimate cause is fully understood.
Also on Thursday, Congressman Dana Rohrabacher declared that the plant should not be relicensed in 2022 unless it upgrades to newer, safer technologies.
Rohrabacher said the basic technology at San Onofre and other nuclear stations across the country is 50 years old. New power-station technologies are available that are much safer and more effective, he said, and San Onofre and other nuclear sites should move to them.
That's the message that Rohrabacher, a senior member of the House Committee on Science, Space and Technology, said he will take back to Washington. …
“We should not be trying to extend their life. When they come to the end of their life, we should move immediately to the new technologies that will eliminate the problem of leftover waste, possible radiation leaks and bomb material being left over."
Asked how long it would take, Rohrabacher said, "I think we could build the first prototype within five years and we should be able to start building them modularly. These are so safe, we could build them and put them together and ... we could have a mass distribution within 10 years."
Rohrabacher cited technologies like high-temperature, gas-cooled reactors and thorium reactors, according to the San Clemente Patch.