ML22012A057

Issuance of RAIs for Surry Unit 1, Spring 2021 Steam Generator Tube Inspection

ML22012A057
Person / Time
Site:	Surry
Issue date:	01/11/2022
From:	John Klos Plant Licensing Branch II
To:	Geoffrey Miller, Stoddard D Virginia Electric & Power Co (VEPCO)
Klos, J
References
Download: ML22012A057 (2)

Text

From: Klos, John Sent: Tuesday, January 11, 2022 1:48 PM To: gary.d.miller@dominionenergy.com Cc: Klos, John

Subject:

Formal issuance of RAIs for Surry Unit 1, Spring 2021 Stm. Gen. Tube Inspection Importance: High Follow Up Flag: Follow up Due By: Thursday, February 03, 2022 12:00 PM Flag Status: Flagged

Gary, By letter dated August 27, 2021 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML21243A313), Virginia Electric and Power Company (the licensee) submitted information summarizing the results of the spring 2021 steam generator (SG) tube inspections performed at Surry Power Station (Surry), Unit 1. These inspections were performed during refueling outage (RFO) 30.

Title 10 of the Code of Federal Regulations Part 50.36 establishes the requirements for pressurized water reactors to have technical specifications (TS) which include a SG program with specific criteria for the structural and leakage integrity, repair, and inspection of SG tubes.

Specifically, Surrys Technical Specification (TS) 6.6.A.3 requires that a report be submitted within 180 days after Tavg exceeds 200°F following completion of an inspection of the SGs performed in accordance with TS 6.4.Q, Steam Generator (SG) Program. Additionally, these requests for additional information (RAIs) were discussed with your staff and it was determined that a clarification call was not required for these RAIs To complete its review of the inspection report, the U.S. Nuclear Regulatory Commission staff requests the following additional information. This request is now released formally with a 30 day calendar response period; thereby, these RAIs are due on February 10, 2022.

1. Please identify any differences compared to the RFO 29 (Fall 2019) inspections in the sampling strategy for eddy current examination of locations such as tube support plate (TSP) intersections, freespan dings, and bulges. The RFO 29 sampling strategy was described in the request for additional information response dated June 23, 2020 (ADAMS Accession No. ML20181A308). As part of the response, please provide the definitions for dents and dings applied to Surry Unit 1 SG inspections.

2. With respect to the stress corrosion crack indication in SG C,

a. Was the indication located in an anomaly, such as an over-expansion?

b. Discuss the relative performance of the array probe and the +Point probe at the crack location, including the results of any lookbacks from previous inspections for the location with the crack indication.

3. With respect to the secondary-side inspections, please clarify for each SG whether foreign objects or loose parts were removed, and the number and type of objects removed. In addition, please describe any foreign objects or loose parts known to remain in the SGs.

4. The spring 2021 inspection revealed perforations of moisture separator riser barrels in SG C attributed to erosion. Please provide the following additional information:

a. Considering no such degradation was described in the previous inspection reports for SG B (fall 2019, fall 2016), SG C (spring 2018), or SG A (spring 2015), is this considered a new form of degradation or change in trend for previously detected degradation?

b. How is the potential for loose parts from this degradation being managed?

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c. Please describe plans for future inspection of the moisture separators and other steam drum components and structures.

Thanks in advance, John Klos DORL Mcguire, Surry Licensing Project Manager U.S. NRC, Office of Nuclear Reactor Regulation (NRR),

Division of Operating Reactor Licensing (DORL),

NRC/NRR/DORL/LPL21, MS O9E3 Washington, DC 205550001 301.415.5136, John.Klos@NRC.gov 2