In a letter to the Nuclear Regulatory Commission, Senator Barbara Boxer and Representative Edward Markey of Massachusetts have charged that Southern California Edison (SCE), the operator of the beleaguered San Onofre Nuclear Generating Station, was "aware of serious problems with the design of San Onofre nuclear power plant's replacement steam generators before they were installed." SCE has strongly denied Boxer and Markey's charges.
A leak in a tube in one of those generators forced San Onofre's Unit 3 to shut down in January 2012. Unit 2 had been shuttered for maintenance three weeks before, and the plant has remained offline since.
In the letter, sent February 6 to NRC Chair Allison Macfarlane, Senator Boxer and Representative Markey allege that SCE installed the new generators despite knowing of the flaws, and that the utility then declined to make safety modifications to the generators that would have triggered formal review under the NRC's license amendment process.
Boxer and Markey learned of the alleged failings in SCE practices while reviewing a report on the generator leaks written by Mitsubishi Heavy Industries (MHI), the contractor that supplied the generators. In their letter, Boxer and Markey detail the alleged practices that drew their attention
The Report indicates that Southern California Edison (SCE) and MHI were aware of serious problems with the design of San Onofre nuclear power plant's replacement steam generators before they were installed. Further, the Report asserts that SCE and MHI rejected enhanced safety modifications and avoided triggering a more rigorous license amendment and safety review process.
For example, the Report states that although SCE and MHI accepted some adjustments to the replacement steam generators, further safety modifications were found to have "unacceptable consequences" and were rejected: "Among the difficulties associated with the potential changes was the possibility that making them could impede the ability to justify the RSG [replacement steam generator] design" without the requirement for a license amendment. The Report also indicates that SCE's and MHI's decision to reject additional safety modifications contributed to the faulty steam generators and the shutdown of reactor Units 2 and 3.
Boxer and Markey urge the NRC to investigate fully:
This newly-obtained information concerns us greatly, and we urge the NRC to immediately conduct a thorough investigation into whether SCE and MHI did in fact fail to make needed safety enhancements to avoid the license amendment process. All people in our nation, including the 8.7 million people who live within 50 miles of the San Onofre plant, must have confidence in the NRC's commitment to put safety before any other concern. We believe this alarming Report raises serious concerns about SCE's and MHI's past actions. Safety, not regulatory short cuts, must be the driving factor in the design of nuclear facilities, as well as NRC's determination on whether Units 2 and 3 can be restarted.
For its part, SCE -- which owns the plant along with San Diego Gas and Electric and the City of Riverside -- has denied the allegations in the strongest possible terms. In a public response to Boxer and Markey issued Wednesday, the utility stated that public safety was its foremost concern:
It is simply not accurate to suggest, as the letter does, that when they were installed "SCE and MHI were aware of serious problems with the design of San Onofre nuclear plant's steam generators." Indeed, MHI, the manufacturer of the steam generators, warranted the steam generators to be free from defects for 20 years after installation.
SCE would never, and did not, install steam generators that it believed would not perform safely. SCE, like other utilities seeking to replace its steam generators, sought to purchase replacement steam generators that would meet or improve upon the safety standards and performance of the original steam generators. SCE's design specifications followed industry standards for compliance with NRC processes. In fact, SCE submitted two license amendments during the replacement steam generator review process, which the NRC approved. The plant's unit 2 was taken out of service Jan. 9, 2012, for a planned outage. Unit 3 was safely taken off line Jan. 31, 2012, after station operators detected a small leak in a steam generator tube. Each unit will remain shut down until the NRC is satisfied that the unit is safe to operate.
The factual battle will likely shape up to be a war of words between SCE and MHI, as each firm seeks to avoid liability.
In the meantime, anti-nuclear activists are not pleased with the allegations contained in the MHI report. On Thursday, the environmental group Friends of the Earth (FOE), which has sought to prevent the nuclear plant's re-opening, demanded that the NRC release the entire MHI document to the public, along with any other documents the NRC may have in its possession that may shed light on SCE's alleged foreknowledge of flaws in the generators.
"At stake is not only the NRC's own credibility as the nation's nuclear regulator, but also the right of the millions of Southern Californians who live near these crippled reactors to know the truth about what Edison knew about this dangerously defective equipment," said FOE's Erich Pica. "It is not acceptable for the NRC to suppress these documents pleading that they might contain proprietary information -- when millions of families are at risk it is the right of the public, not the profits of the company, that is most important."