NRC gives Edison go-ahead to resume moving nuclear waste at San Onofre
Nine months after work came to a screeching halt at San Onofre Nuclear Generating Station, the Nuclear Regulatory Commission on Tuesday, May 21, gave the green light to resume moving nuclear waste from wet fuel pools into safer, dry storage.
“The NRC made its determination following extensive review of technical data submitted by(operator Southern California) Edison regarding the possible effects of scratching on spent fuel canisters during fuel loading operations,” officials said in an announcement.
Detail behind the NRC’s reasoning will be discussed at a “virtual public meeting” from noon to 1 p.m. June 3. People can register for the webinar at nrc.gov, then submit written comments and questions.
The NRC’s announcement “is an important milestone in the ultimate journey to permanent offsite storage of the spent nuclear fuel,” Edison spokesman John Dobken said by email.
Some remain wary.
“It is troubling that the NRC’s decision relied on data provided by Edison, a company with an incentive to resume loading as quickly as possible,” said U.S. Rep. Mike Levin, D-San Juan Capistrano, in a statement.
“The NRC’s decision-making process requires a greater degree of independence to best serve the public interest.”
What happened?
The fuel transfer ceased on Aug. 3 after a 50-ton canister filled with highly radioactive waste got stuck on a rim near the top of the 18-foot-deep vault where it was to be entombed at the shuttered facility. Workers didn’t realize that the slings supporting the canister’s massive weight had gone slack. It hung there, unsupported, for close to an hour, in danger of dropping.
In November, the NRC laid blame squarely at Edison’s feet, saying it “fell asleep at the switch” and that the near-drop resulted from inadequate training, oversight and supervision.
But the NRC also was concerned about scratches the canisters endured as they were lowered into the vaults, and wouldn’t allow work to resume until it understood what, if any, risk scratches pose to the canisters’ integrity.
Edison’s new visual inspection system, and an independent analysis of the maximum depth of scratches, lead to the conclusion that they do not pose a safety concern, officials said.
Scratches can indeed break through the chrome oxide layer that protects stainless steel from pitting and general corrosion. But any new surfaces exposed by wear are quickly — within weeks — covered by a newly formed chrome oxide layer, due the reaction of air with the chrome alloy in stainless steel, Edison said.
As a result, such scratches will not have a significant effect on pitting and general corrosion rates, it concluded.
New checks and balances
Edison has adopted many new checks and balances that will prevent errors of the past from repeating themselves, officials have said.
Along with Holtec International, its waste storage contractor, Edison has created “a more robust program through better procedures, better training, and more intrusive oversight.” Cameras and alarms have been added to machinery so many eyes and ears can monitor loading in real time.
“We have demonstrated these improvements are effective and sustainable through numerous dry runs, regulatory inspections and independent reviews,” Dobken said.
No decision has been made yet on precisely when fuel transfer will resume, but Edison promised “timely updates to the community and our stakeholders as we move through this process,” Dobken said.
David Victor, chairman of the volunteer Community Engagement Panel advising Edison on the plant’s decommissioning, has been expecting this announcement for some time.
“It is why we have focused on Holtec management and the need for it to focus on building confidence in its management process,” Victor said. “The engineering and technology are not the issue.”
Victor and other CEP leaders got into a war of words with Holtec over their concerns about the contractor’s performance.
Critics have many questions.
“It is troubling that the NRC is inviting public comments after they have made their decision,” said Charles Langley, executive director of Public Watchdogs.
“We are so disheartened by the failure of the NRC to enforce the law that we believe it needs to be replaced root and branch by a different agency that is capable of protecting the public and enforcing nuclear safety laws,” he said.
Rep. Levin has launched his own task force to study safety challenges at the plant and wants a full-time NRC inspector there because “Edison proved after the ‘near-miss’ canister incident that we need a higher level of transparency, accountability and oversight.”
The NRC typically stations full-time inspectors at working nuclear plants, not at shuttered ones like San Onofre, which powered down in 2012.
“Until a full-time NRC inspector is in place, I will remain strongly concerned about the loading of spent nuclear fuel at this site,” Levin said.