ML22048B552

LTR-22-0010 Reply to Geoff Gilbert Email Concern About Seabrook Station Concrete Degradation

ML22048B552
Person / Time
Site:	Seabrook
Issue date:	02/17/2022
From:	Matt Young NRC/RGN-I/DORS
To:	Laurie Pinkham NRC Region 1
Shared Package
ML22020A255	List: ML22020A254 ML22048B552
References
LTR-22-0010
Download: ML22048B552 (2)

Text

Pinkham, Laurie ADAMS Accession No: ML22048B552 From: Young, Matt Sent: Thursday, February 17, 2022 1:20 PM To: Pinkham, Laurie

Subject:

FW: Response to Email Dated 1-20-2022 "Seabrook Station Concrete Degradation needed repairs-timeline?"

Attachments: 01-20-22 Mr. G. Gilbert Email.pdf From: Young, Matt <Matt.Young@nrc.gov>

Sent: Thursday, February 17, 2022 1:20 PM To: Geoff Gilbert [email address deleted]

Cc: Young, Matt <Matt.Young@nrc.gov>

Subject:

Response to Email Dated 1202022 "Seabrook Station Concrete Degradation needed repairstimeline?"

Dear Mr. Gilbert,

I am responding to your January 20, 2022, email to NRC Chairman Christopher T. Hanson expressing your concern about the continued safety of Seabrook Station in light of recent inspection findings related to alkali-silica reaction (ASR) in concrete structures at the plant. We understand your concerns.

Let me begin by saying we carry out an extensive inspection and oversight program at each of the nations nuclear plants. We have at least two NRC inspectors based at each site on a full-time basis. Their work is supplemented by inspections by specialist inspectors from the NRCs regional office. As part of our baseline inspection program, we inspect NextEras implementation and oversight of its structural monitoring program.

Our inspections ensure the company identifies, manages, and promptly corrects ASR issues to support the continued safe operation of the plant. Based on oversight and inspection activities, we continue to conclude Seabrook is operating safely, and NextEra is managing identified problems per the site's license requirements. Additional information on the Reactor Oversight Program is available on the NRC website at https://www.nrc.gov/reactors/operating/oversight.html.

The ASR inspection finding discussed in the C-10 blog post was from an NRC inspection report issued in the Fall 2021. The report documented one green, or very low safety significance, finding for NextEras failure to consider ASR growth-rate data on one structure. The specific locations in the structure were in two underground hallways and one wall in the Control and Diesel Generator Building. The issue was determined to be of very low safety significance because the structure remained capable of performing its safety function. While the NRC inspectors found that NextEra was following the NRC-approved methodology for monitoring and evaluating structures affected by ASR, NextEras assessment did not look forward to ensuring the areas would remain functional until the next scheduled inspection, given the increased ASR growth.

Subsequent evaluation by NextEra and reviewed by NRC determined these areas would remain functional. We continue to have confidence in the ASR monitoring and evaluation program.

There was also an ASR-related finding in the most recent Seabrook report, which was issued on February 10, 2022. As weve explained, we continue to inspect NextEras implementation and oversight of its structural monitoring program regarding ASR to ensure issues are identified, managed, and corrected in a timely manner that supports continued safe operation of the plant. During inspections conducted in the fourth quarter of 2021, the resident inspector staff, supported by regional and headquarters specialists, reviewed the companys monitoring and maintenance of the plants containment internal structures, including the reactor cavity pit area, which provides access to the underside of the reactor vessel area. As part of the review, the inspectors 1

conducted multiple independent walkdowns and reviewed the results of previously documented licensee inspections and evaluations.

Our inspectors identified a finding of very low safety significance because NextEra did not document and evaluate conditions observed in 2017 as indicative of ASR impacts in the reactor cavity pit area. The finding was of very low safety significance because an operability evaluation completed by NextEra and reviewed by NRC inspectors provides reasonable assurance that the structure remains operable and capable of performing its safety function. The licensee has commenced a comprehensive evaluation of the structure per the structures monitoring program and also established increased monitoring of the containment internal structures area. This required evaluation will be reviewed by NRC inspectors when completed.

Our website has a page dedicated to our oversight of the ASR issue at Seabrook, https://www.nrc.gov/reactors/operating/ops-experience/concrete-degradation.html#acrs. On it, you will find a summary of the issue and dozens of other relevant documents.

Thank you for expressing your concerns. Based on the results of our inspections to date and the continued application of the structures monitoring plan that NextEra is required to implement per the license, the plant remains safe to operate.

Should you have any further questions, please feel free to contact me.

Sincerely, Matt Young Nuclear Regulatory Commission Region I, Project Branch 2, Chief Oversight of Seabrook, Millstone and Beaver Valley 610-337-5205 2