The operator of California’s last nuclear power plant, which just got a new lease on life, said that the facility’s system for managing reactor coolant pressure was leaking, according to a recent letter to the Nuclear Regulatory Commission.
During an October refueling outage at Diablo Canyon Power Plant, Pacific Gas & Electric (PG&E) discovered a “through-wall” leak from a faulty weld on one of the plant’s reactor coolant system refill lines, the utility told NRC in a letter dated Dec. 21.
Although there was “no active leak” from the line at the time of discovery, PG&E investigators determined that it was the source of an issue because of the presence of boric acid residue around the weld, the letter said.
The leak “did not adversely affect the health and safety of the public or on-site personnel,” PG&E said, and the faulty weld was repaired Oct. 31. There was no indication of any other leakage, the utility told NRC.
This comes as the Avila Beach, Calif., Diablo Canyon plant is gearing up to operate five years past its initially scheduled shutdown date. Although the plant’s two reactors were set to go dark in 2024 and 2025, respectively, the Department of Energy in November awarded roughly $1.1 billion in funding to the facility as part of the agency’s civil nuclear credits program. The funding, coupled with incentives from the state, should help keep the plant online until 2030 or so.
A sweeping climate bill signed in August by California Gov. Gavin Newsom (D) opened up an additional $1.4 billion in state-stewarded loans to prop up Diablo Canyon for an additional five years.
PG&E, meanwhile, is seeking an NRC license extension for Diablo Canyon. The utility has asked the agency to pick up where it left off on a similar license renewal request filed in 2009 to expedite the process.
