‘Unsettling and Unacceptable’ Negligence Uncovered at Diablo Canyon
By Nick Welsh — March 29, 2022 — The Santa Barbara Independent — www.independent.com
The Office of the Inspector General issued a damning report on a significant failure by nuclear safety inspectors charged with ensuring the safe operation of the Diablo Canyon nuclear power plant in Avila Beach in southern San Luis Obispo County that led to one of the plant’s two reactors being shut down for eight days in July 2020.
A steel pipe that fed water into the backup cooling system for one of the two nuclear reactors sprung a small leak, allowing 3.9 gallons of water to escape a minute through a hole 1/16th of an inch in diameter. The leak occurred because the pipe had become badly corroded from exposure to moisture that had gotten in underneath the pipe’s insulation material. But the real problem highlighted by the Office of Inspector General for the Nuclear Regulatory Commission (NRC) was the failure of on-site safety inspectors with the NRC to detect the corrosion that led to the leak during an inspection of the plant that took place three months prior.
Worse yet, according to the report, inspectors claimed to have inspected the area of the plant in question, when in fact they had not. “The NRC had not inspected the area where the leak occurred even though its inspection report indicated that inspectors had conducted a complete walkdown of the AFW (auxiliary feedwater system) in April 2020,” the report states.