NL-20-0816, Response to Request for Clarification Regarding the Refueling Outage 1R29 Steam Generator Tube Inspection Report

Response to Request for Clarification Regarding the Refueling Outage 1R29 Steam Generator Tube Inspection Report

ML20199M369
Person / Time
Site:	Farley
Issue date:	07/17/2020
From:	Gayheart C Southern Nuclear Operating Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
NL-20-0816
Download: ML20199M369 (3)

Text

Cheryl A. Gayheart 3535 Colonnade Parkway Regulatory Affairs Director Birmingham, AL 35243 205 992 5316 cagayhea@southernco.com July 17, 2020 Docket No.: 50-348 NL-20-0816 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D. C. 20555-0001 Joseph M. Farley Nuclear Plant - Unit 1 Response to Request for Clarification Regarding the Refueling Outage 1R29 Steam Generator Tube Inspection Report Ladies and Gentlemen:

In accordance with the requirements of Joseph M. Farley Nuclear Plant Technical Specification 5.6.10, Southern Nuclear Operating Company submitted a report of the steam generator tube inspections performed during the twenty-ninth outage on Unit 1 (1R29) on April 17, 2020.

By email dated June 16, 2020, the NRC provided a request for clarification. The enclosure to this letter responds to that request.

This letter contains no NRC commitments. If you have any questions, please contact Jamie Coleman at 205.992.6611.

Respectfully submitted, Cheryl A. Gayheart Regulatory Affairs Director CAG/was/sm

Enclosure:

Response to Request for Clarification - 1R29 Steam Generator Tube Inspection Report cc: Regional Administrator, Region ll NRR Project Manager - Farley Nuclear Plant Senior Resident Inspector - Farley Nuclear Plant RTYPE: CFA04.054

Joseph M. Farley Nuclear Plant - Unit 1 Response to Request for Clarification Regarding the Refueling Outage 1R29 Steam Generator Tube Inspection Report Enclosure Response to Request for Clarification - 1R29 Steam Generator Tube Inspection Report

Enclosure to NL-20-0816 Response to Request for Clarification - 1R29 Steam Generator Tube Inspection Report NRC Request for Clarification The NRC staff is reviewing the information SNC submitted on April 17, 2020 (ML20108F618), summarizing the results of the fall 2019 steam generator (SG) tube inspections for Farley, Unit 1. The NRC staff requests the following clarification:

Section B (Active Degradation Mechanisms Found) of the report states there were two new tube support plate (TSP) wear indications (and twenty-three previously identified indications in nineteen different tubes). However, in comparing Table 2 of the 2019 report to Table 2 of the 2015 report (ML15302A277), the NRC staff identified three new TSP indications in 2019 (row 3 column 4 in SG A, row 1 column 76 in SG B, and row 1 column 45 in SG C).

Please clarify the number of newly detected TSP indications in 2019 (1R29).

SNC Response:

In the April 17, 2020 SNC submittal, there were three TSP wear indications reported that were not reported prior to the Farley 1R29 inspections. Two indications (SGA Row 3 Column 4 and SGB Row 1 Column 76) were first identified during 1R29 and reported as new in section B of the report under the heading Tube Support Plate (TSP) Wear. The following are the three locations of the indications:

1. SGA Row 3 Column 4 (new)

2. SGB Row 1 Column 76 (new)

3. SGC Row 1 Column 45 This tube was not inspected with Bobbin in 1R26 (2015). Based on the wear reading in 1R29, the data from 1R23 (2010) was reviewed. The 1R23 data showed a low wear signal confirming that it was present in 1R23. However, it was not reported in the 1R23 report, likely due to the low percentage of wear.

Based on the historical data review confirming that the indication existed previously, it was viewed as a previously identified indication and not a new indication.

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