The U.S. Nuclear Regulatory Commission from July to October conducted 10 unannounced inspections of spent fuel transfer operations at the San Onofre Nuclear Generating Station (SONGS) in California.
The inspections are part of the agency’s response to several problems in the project, notably an August 2018 incident in which a canister was put at risk of a nearly 20-foot drop into its storage slot alongside the Pacific Ocean. That mishap led to a nearly yearlong suspension of fuel loading and a $116,000 fine from the NRC on plant majority owner Southern California Edison.
The unannounced, mostly multi-day inspections were conducted between July 1 and Oct. 25, according to information sent on Dec. 6 by NRC Chairman Kristine Svinicki to U.S. Rep. Mike Levin (D-Calif.), whose congressional district covers SONGS.
During the visits, agency inspectors monitored the loading of used-fuel assemblies into storage canisters, the transport of the canisters to the plant’s dry-storage pad, and their installation into underground slots.
“Specifically, NRC inspections looked at (1) licensee practice runs; (2) training for personnel to perform the fuel loading campaign; (3) transfer and downloading of three canisters from the spent fuel pool into the UMAX [independent spent fuel storage installation]; (4) canister flushing activities on site; (5) loading of a fuel canister containing damaged fuel and (6) activities related to four additional canisters including processing, welding, and preparing to move them,” according to the NRC.
Agency inspectors also conducted a quarterly decommissioning inspection at the plant from Aug. 26-29.
Southern California Edison closed SONGS’ final two operational reactors in 2013 after they were installed with faulty steam generators. It hired energy technology firm Holtec International the following year to move the reactors’ spent fuel from wet storage to dry storage.
As of last week, 43 of 73 spent-fuel canisters had been placed into storage. Southern California Edison expects to complete the offload by the middle of 2020. At that point, about 3.5 million pounds of spent fuel from SONGS’ three reactors will be in dry storage.
