SAN DIEGO – A letter from the manufacturer of steam generators at the San Onofre Nuclear Generating Station shows that Southern California Edison believed the systems were safe before they were installed, refuting claims from anti-nuclear activists, the utility announced today.
SCE, the plant’s majority owner and operator, released a statement concerning a letter from Mitsubishi Heavy Industries of Japan to the Nuclear Regulatory Commission.
Opponents of plans to restart a reactor at the plant, which has been shut down for more than a year, contend that the Mitsubishi information reveals that SCE knew of problems with the generators back in 2005, but opted against major alterations in order to avoid a costly license amendment process.
”The anti-nuclear activists have called the MHI report a bombshell, which couldn’t be further from the truth,” Pete Dietrich, SCE senior vice president and chief nuclear officer, said. ”In fact, the MHI letter explains that SCE and MHI rejected the proposed design changes referenced in the evaluation because those changes were either unnecessary, didn’t achieve objectives or would have had adverse safety consequences.”
He said MHI repeatedly reassured SCE that based on their testing, the steam generators met safety requirements and would function for 20 years.
A small leak in one of the plant’s two reactors forced the shutdown in January 2012. No one was hurt.
The other reactor was undergoing scheduled maintenance at the time. SCE wants to start that one back up at 70 percent power.
The NRC has indicated a decision could come on the utility’s restart plan in late April or May.
”As with all engineering evaluations, the MHI letter and report describe a technical evaluation process and need to be read in their entirety to understand the conclusions reached,” Dietrich said. ”The activists are taking portions of paragraphs and sentences out of context, and using them as the basis of their allegations that SCE knew of design defects when the generators were installed, but failed to make changes to avoid licensing requirements. That is untrue.”
SCE, which owns nearly 80 percent of the plant, blames MHI’s use of faulty computer code, which failed to predict conditions in the steam generators.
MHI never suggested to SCE that changes to the specification needed to be made, because their computer modeling didn’t indicate such a modification was necessary or required, the utility said.
Separately today, the NRC announced that three administrative law judges of the Atomic Safety and Licensing Board will hear oral arguments March 22 in Rockville, Md., on a request by the anti-nuclear group Friends of the Earth to convene a hearing on steps laid out by the NRC before the agency can consider allowing a restart.
The commissioners last November asked the ASLB to consider whether a ”Confirmatory Action Letter” outlining the requirements triggers an opportunity for a hearing, and whether FOE has met the legal requirements to participate.