Press Release-22-019, NRC Responds to Inspector General'S Diablo Canyon Event Inquiry

Press Release-22-019: NRC Responds to Inspector General'S Diablo Canyon Event Inquiry

ML22131A140
Person / Time
Site:	Diablo Canyon
Issue date:	05/03/2022
From:	Office of Public Affairs
To:
References
Press Release-22-019
Download: ML22131A140 (1)

Text

No: 22-019 May 3, 2022 CONTACT: Office of Public Affairs, 301-415-8200 NRC Responds to Inspector Generals Diablo Canyon Event Inquiry The Nuclear Regulatory Commission today released a response to an NRC Inspector General Report published last month critical of an agency inspection at the Diablo Canyon nuclear power plant in California.

Ordered by NRC Executive Director for Operations Dan Dorman, the response highlights a number of factual errors and takes issue with several portions of the IG report.

After reviewing the Inspector Generals event inquiry, our technical staff determined that the Reactor Oversight Program and its associated inspection program continue to provide reasonable assurance of adequate protection of public health and safety, said Dorman. Resident inspectors are vital to the NRC safety mission. I have full confidence in the qualification, abilities, and professionalism of the inspectors involved in this event inquiry as well as all of our inspectors.

Among the findings outlined in the response:

• The leak in the auxiliary feedwater system did not cause the plant to shut down as stated by the IG, nor did it compromise plant safety. The Diablo Canyon plant has operated safely and continues to do so.

• The staff found no evidence that the auxiliary feedwater pipe corrosion hidden under metal jacketed insulation should have been identified by NRC inspectors before the leak occurred. The resident inspectors then assigned to Diablo Canyon followed appropriate guidance during their inspection of the system and regional and headquarters management appropriately determined that the leak had very low safety significance.

Corrosion under insulation, which caused this leak, is known to the industry and the NRC.

• The agency remains confident in the effectiveness of its inspection program, which is one of many ways in which it verifies nuclear power plant safety. Other methods include Reactor Oversight Program performance indicators, rigorous plant licensing requirements, robust design margins for every plant, redundant safety systems that provide defense in depth, and operator and training requirements to enable plant operators to respond to equipment malfunctions and unexpected events.

Included in the NRC response is acknowledgement that the IG identified opportunities to improve the NRCs programs and processes and strengthen its inspection program.