By Jim Shilander
Southern California Edison says an engineering assessment of the San Onofre Nuclear Generating Station states that the utility could operate Unit 2 at full power for 11 months at full tube integrity.
As part of the Nuclear Regulatory Commission’s investigation into steam generator tube integrity at SONGS, the commission had asked the utility whether it might be possible to operate at full capacity. Edison is proposing restarting Unit 2 at 70 percent capacity and running for five months to assess tube wear. Unit 2 has remained shut down after tube wear caused a rupture in a steam generator tube in Unit 3 last January, while Unit 2 was down for refueling. Tube wear was subsequently discovered in the steam generator tubes of Unit 2, but not to the same level as had taken place in Unit 3.
An Edison news release stated that the assessment was performed by Sunnyvale firm Intertek APTECH, which it said performed similar assessments for nuclear plants across the country.
“This evaluation confirms the structural integrity of the Unit 2 steam generators at 100 percent power, as requested by the NRC,” Pete Dietrich, Edison senior vice president and chief nuclear officer said in the release.
“While we have no intent to restart Unit 2 at full power, this demonstrates the amount of safety margin we have built into our analyses.”
San Clemente Green founder Gary Headrick, who opposes the plant restart, said in a news release that the finding only means that a rupture could take place if the company operated the plant beyond 11 months.
“It is obvious at this point that Edison will say or do anything to avoid the scrutiny of a license amendment hearing,” Headrick stated.
A final decision on the restart proposal at 70 percent is expected by May or June, to allow the NRC to review the final information sent by Edison. The NRC has stated that an additional public meeting will be held in Southern California before a decision is made.