Federal report details inspection failures at Diablo Canyon Nuclear Power Plant
A new report on safety inspections at Diablo Canyon Nuclear Power Plant in San Luis Obispo County is out today, and while it found that Diablo Canyon is currently operating safely, it also identified failures by Nuclear Regulatory Commission (NRC) inspectors to appropriately identify several issues at the facility.
The Office of the Inspector General for the NRC, who conducted the investigation and released the Event Inquiry Report, began an investigation after the plant’s auxiliary feedwater (AFW) system failed and led to an 8-day shutdown of one of the nuclear reactors in July 2020. The AFW system is a “backup water supply that can be used to cool the reactor if normal feedwater is out of service,” according to the report.
Specifically, the OIG found that inspectors “failed to identify piping insulation on the AFW system that had long been in a degraded condition, and that led to a leak.”
The report said that the investigation revealed that the NRC “had not inspected the area where the leak occurred, even though its inspection report indicated that the inspectors had conducted a complete walkdown of the AFW system in April 2020, three months prior to the leak and shutdown.”
In addition to that, the investigation also found that “the number of hours NRC staff spent directly inspecting both reactors’ AFW systems for the complete walkdown in April 2020 was fewer than recommended in the applicable NRC inspection procedures.”
The Office of the Inspector General pointed out, however, that the AFW system has since been improved by licensee PG&E and meets regulatory requirements, stressing that the power plant continues to operate safely.
Central Coast Congressman Salud Carbajal reacted to the report Monday, saying in a statement: “The findings released today by the NRC’s Inspector General are unsettling and unacceptable. The safety and wellbeing of the entire San Luis Obispo community relies on federal inspectors adhering to those safety protocols, and the negligence detailed in this report will erode the public trust in those who are tasked with keeping us safe.”
Carbajal also urged the NRC to hold its inspectors accountable for “breaking protocol” and rebuild confidence in their operations at the power plant. He also said he will formally ask NRC leaders in the coming days to detail what went wrong during the inspections and how they will enforce safety regulations until Diablo Canyon closes.
The plant’s operator, PG&E, plans to close Diablo Canyon completely by 2025.