Decommissioning contractors for the San Onofre Nuclear Generating Station (SONGS) are readying for removal of large components from the plant’s two reactors, according to a recent update.
SONGS majority owner Southern California Edison (SCE) laid out its decommissioning schedule during an Aug. 20 meeting of the site’s Community Engagement Panel (CEP).
Right now, SCE and its contractors are enlarging the openings to the containment domes of reactor Units 2 and 3 to allow huge pieces of equipment to go through, said Doug Bauder, the utility’s vice president for decommissioning and chief nuclear officer at SONGS.
Workers are also removing asbestos from the domes, collecting and studying data on radiation, and delivering containers for tools and wastes to the domes.
“The major things that we’re going after right now are inside containment and getting ready for reactor vessel cut-up,” SONGS Plant Manager Lou Bosch said during a separate Aug. 11 online conference organized by the American Nuclear Society.
The preparations to move and the actual removal of major pieces of equipment from the domes will last from now through 2024, Vince Bilovsky, SCE’s deputy decommissioning officer, told the Community Engagement Panel. Smaller electrical and mechanical components will be handled in 2025. Components from the turbine buildings will be removed from 2021 to 2024. The buildings are scheduled to be torn down in 2026.
The final surveys for radioactivity before declaring decommissioning is complete will occur in 2027. At the end of the project, radiation levels must be reduced to the level at which the property can be put to other uses, per federal regulations.
Within eight years, all that will remain of the facility on the oceanside grounds of Marine Corps Base Camp Pendleton in San Diego County will be the spent-fuel storage pad, seawall, and switchyard, Bosch said. “Everything else goes back to the beach.”
The projected $4.4 billion decommissioning began in earnest in February, managed by SONGS Decommissioning Solutions, a joint venture of Los Angeles-based infrastructure specialist AECOM and Salt Lake City-based nuclear services firm EnergySolutions. AECOM plans to sell its stake in the contractor, but stakeholders have remained mum regarding the potential buyer.
Decommissioning is expected to produce roughly 285,000 tons of Class A low-level waste, to be shipped by rail to EnergySolutions’ disposal facility in Clive, Utah. Roughly 35 tons of Class B and C low-level wastes are expected to be shipping by truck to the Waste Control Specialists disposal operation in Andrews County, Texas. Another 125 tons of wastes expected to be classified as Greater-Than-Class C (GTCC) level will be stored at SONGS alongside spent reactor fuel until some off-site storage or disposal option is available.
All of the B and C wastes and 83% of the Greater-Than-Class C waste will be parts of the reactors. The remaining 17% of the GTCC waste will be metals from the spent fuel pools in the two reactors. The Class A wastes will be everything else in the containment domes.
San Onofre had three power reactors, all now retired. Unit 1 closed in 1992 and has been mostly decommissioned. Its pressure vessel was shipped to EnergySolutions’ Utah facility earlier this summer.
Units 2 and 3 were permanently shuttered in 2013 after they were equipped with faulty steam generators.
This month’s meetings came only days after Southern California Edison announced it had on Aug. 7 completed the transfer of spent fuel rods from Units 2 and 3 from their cooling pools into the site’s expanded independent spent fuel storage installation (ISFSI). Including the spent fuel from Unit 1, the storage pad holds about 3.5 million pounds of radioactive spent fuel.
Fifty canisters store material from all three reactors. Contractor Holtec International conducted the latest offload, encompassing 73 canisters of used fuel from Units 2 and 3. The spent-fuel transfer began in 2018, then was halted for nearly a year following a mishap in August of that year in which one canister was left at risk for nearly an hour of an 18-foot drop into its storage slot. That led to a special inspection and $116,000 fine from the Nuclear Regulatory Commission. Operations resumed in July 2019, under what SCE said were improved procedures and oversight.
The canisters are stored roughly 100 feet from the Pacific Ocean, raising concerns about rising sea levels from global warming and flooding from tsunamis. Edison expects to have a master plan mapped out by early 2021 on options for off-site relocation of the used fuel, under the terms of a 2017 settlement in a lawsuit that had challenged the expansion of the used-fuel pad to take the material from Units 2 and 3.
The Community Engagement Panel plans to return to the spent-fuel issue in depth at its Nov. 19 meeting.
“We want to become more focused on this after the (November) election on how to get this fuel off-site. How do we make a political push?” said CEP Chairman David Victor.
Southern California Edison has about 110 employees remaining at SONGS following the latest round of layoffs earlier this month, according to Bosch.
The utility transitioned the site to an ISFSI-only property on Aug. 10, he noted during the American Nuclear Society event. The day ended with the scheduled layoffs of about 150 SCE employees, Bosch said.
SONGS had roughly 1,500 workers at the time of its permanent closure in 2013. From that point, SCE has reduced staffing at several points as it has shifted from operations to oversight of the facility, spokesman John Dobken said Tuesday.
“As we neared completion of fuel transfer operations, we began planning a reduction in force that reflects our next transition, to an organization solely focused on safely managing the dry cask storage system and decommissioning oversight,” he wrote in response to questions from RadWaste Monitor. “Employees at San Onofre were well aware of these upcoming changes.”
Impacted departments included operations, engineering, security, and support services, Dobken stated.
The Aug. 10 transition to the ISFSI-only status “essentially means the nuclear focus is reduced to the ISFSI where the spent nuclear fuel is stored,” he wrote. “The majority of San Onofre becomes an industrial deconstruction site, with critical functions, including oversight, focused on the safe dismantlement of plant structures. Resources such as security are re-focused on the dry storage facility and protection of the spent nuclear fuel.”
Editor’s Note: This article has been updated to clarify that 50 older storage canisters hold used fuel from all three of SONGS’ reactors.
