RA-20-0087, Response to Request for Additional Information Regarding Request for Alternative in Accordance with 10CFR 50.55a(z)(1) to Delay the Update of the ASME Code of Record for the First Inspection Period

Response to Request for Additional Information Regarding Request for Alternative in Accordance with 10CFR 50.55a(z)(1) to Delay the Update of the ASME Code of Record for the First Inspection Period

ML20097A026
Person / Time
Site:	McGuire
Issue date:	04/02/2020
From:	Teresa Ray Duke Energy Carolinas
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
RA-20-0087
Download: ML20097A026 (6)

Text

Tom Ray Vice President McGuire Nuclear Station Duke Energy MG01VP 112700 Hagers Feny Rd.

Huntersville, NC 28078 704.946.2305 Tom.Ra:,@duke-energy.com Serial: RA-20-0087 10 CFR 50.55a April 02, 2020 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 MCGUIRE NUCLEAR STATION, UNIT NO. 1 DOCKET NO. 50-369

SUBJECT:

Response to Request for Additional Information Regarding Request for Alternative in Accordance with 10 CFR 50.55a (z)(1) to Delay the Update of the ASME Code of Record for the First Inspection Period

REFERENCES:

1. RA-19-0341, Request for Alternative in Accordance with 10 CFR 50.SSa (z)(1) to Delay the Update of the ASME Code of Record for the First Inspection Period, December 19, 2019 [ML19353C619]

2. RA-20-0031, Revision to Request for Alternative in Accordance with 10 CFR 50.55a (z)(1) to Delay the Update of the ASME Code of Record for the First Inspection Period, January 23, 2020 [ML20023A272]

3. Email from Gregory Croon to Chet Sigmon: Request for Additional Information - McGuire Nuclear Station Unit 1 Delay in Update of the Code of Record for In Service Inspections, March 05, 2020 [ML20071O096]

Ladies and Gentlemen, On December 19, 2019 Duke Energy Carolinas, LLC (Duke Energy) submitted RA-19-0341, Request for Alternative in Accordance with 10 CFR 50.55a (z)(1) to delay the update of the ASME code of record for the first inspection period of the fifth interval for McGuire Nuclear Station Unit 1 (Reference 1). On January 23, 2020, Duke Energy submitted RA-20-0031 as a revision which superseded the original submittal (Reference 2). By letter dated March 05, 2020 the NRC requested additional information needed to complete review of the *Relief Request (Reference 3).

Enclosure 1 provides Duke Energy's response to the Requests for Additional Information. If you have questions concerning this request, please contact Art Zaremba, Manager - Fleet Licensing, at (980) 373-2062.

_:Ji>>,J Tom Ray Vice President McGuire Nuclear Station NRC FORM 366 (04-2017)

U.S. Nuclear Regulatory Commission RA-20-0087 Page 2

Enclosure:

1. Response to Requests for Additional Information cc : (all with Enclosure)

L. Dudes, Regional Administrator USNRC Region II Andy Hutto, USNRC Senior Resident Inspector - MNS M. Mahoney, NRR Project Manager - MNS

RA-20-0087 Enclosure 1 Page 1 of 4 Enclosure 1 Response to Requests for Additional Information

RA-20-0087 Enclosure 1 Page 2 of 4

RAI-01

Confirm that, with the NRC approval of Relief Request RA-20-0031, the length of McGuire, Unit, 1 fourth and fifth 10-year ISI intervals will not be affected and that the fourth ISI interval will still be scheduled to end on November 30, 2021, and the fifth ISI interval will be scheduled to start on December 1, 2021 and end on November 30, 2031.

Response to RAI-01 Duke Energy confirms the length of McGuire, Unit 1, fourth and fifth 10-year ISI intervals will not be affected by the approval of Relief Request RA-20-0031 and the fourth ISI interval remains scheduled to end on November 30, 2021, and the fifth ISI interval is scheduled to start on December 1, 2021 and scheduled to end on November 30, 2031.

RAI-02

Given the licensees statement on page 3 of its January 23, 2020 submittal:

The proposed alternative includes continued use of relief requests submitted and approved for McGuire Unit 1 in the 2nd and 3rd periods of the fourth 10-year Interval, during the 1st period of the fifth 10-year Interval.

a. Provide a list (with ADAMS Accession numbers), of relief requests that were previously approved by the NRC for use in the second and third periods of the fourth 10-year ISI interval of McGuire, Unit 1, that are requested by the licensee for continued use in the first inspection period of the fifth 10-year ISI interval.

Response to RAI-02a Date Submitted / Date SER Approved Serial Nos Description ML Listing / ML Listing Use of Risk Informed Inservice Inspection Program for the 8/13/2013 7/14/2014 13-MN-002 Fourth Inspection Interval, using (ML13234A069) (ML14188C348)

ASME Code Case N-716, (no revision).

RPV Flange Ligament exams 03/29/2017 12/26/2017 17-GO-001 based on EPRI Report (ML17088A846) (ML17331A086) 3002007626 Alternative to the Depth Sizing Qualification Requirement of 09/06/2018 06/20/2019 18-GO-001 Appendix VIII, Supplements 2 (ML18249A008) (ML19128A326) and 10 Use of encoded Phased Array UT (PAUT) in lieu of RT to 05/20/2019 09/17/2019 19-GO-001 perform required examinations (ML19143A072) (ML19254A620) of welds replaced in accordance with ASME Section XI, IWA-4000

RA-20-0087 Enclosure 1 Page 3 of 4

b. For the identified relief requests in above item a, address whether any NRC actions have been taken (e.g., endorsement, with or without conditions, of an ASME Code Case upon which a prior relief request was based) after NRC approval.

Response to RAI-02b The NRC listed Code Case N-716 (no revision) in Table 2 of Regulatory Guide 1.193, ASME Code Cases Not Approved for Use, but provided authorization for McGuire Unit 1 to use Code Case N-716 (no revision) via Relief Request 13-MN-002 (ML14188C348) for the 4th 10-year interval. McGuire Unit 1 plans to continue using Code Case N-716 (no revision) during the 1st Period of the 5th 10-year interval via extended use of Relief Request 13-MN-002 as described in RAI-02(a). Revision 19 of Regulatory Guide 1.147 allows the use of Code Case N-716-1 without conditions; therefore, it is expected no Relief Request will be needed to use this Code Case after the 1st Period of the 5th 10-year interval.

NRC actions taken (e.g.,

Serial Nos Description endorsement, with or without conditions, of an ASME Code Case upon which a prior relief request was based)

ASME Code Case N-716, (No Revision), Alternative Piping Classification and Examination Requirements,Section XI, Division 1, is Use of Risk Informed Inservice superseded by N-716-1.

Inspection Program for the Fourth ASME Code Case N-716-1, Alternative 13-MN-002 Inspection Interval, using ASME Piping Classification and Examination Code Case N-716, (No Revision) Requirements,Section XI, Division 1, is approved for unconditional use in Regulatory Guideline 1.147, Revision 19.

RPV Flange Ligament exams None.

17-GO-001 based on EPRI Report 3002007626 Alternative to the Depth Sizing None.

Qualification Requirement of 18-GO-001 Appendix VIII, Supplements 2 and 10 Use of encoded Phased Array UT in ASME Code Case N-831, Ultrasonic lieu of RT to perform required Examination in Lieu of Radiography examinations of welds replaced in for Welds in Ferritic Pipe Section XI, 19-GO-001 accordance with ASME Section XI, Division 1, is approved with conditions IWA-4000 for use in Regulatory Guideline 1.147, Revision 19.

RA-20-0087 Enclosure 1 Page 4 of 4

c. Clarify whether it is the licensees intent that the continued use of the identified relief requests (in above item a), for the first period of the fifth 10-year ISI interval is justified by the information provided in the prior licensee submittals for these relief requests, or, for each relief request, provide justifications for continued use in the first inspection period of the fifth 10-year ISI interval.

Response to RAI-02c Relief Request 13-MN-002 Risk Informed program was created to identify high safety significant (HSS) piping, to determine the locations to be inspected within the identified piping, and to identify appropriate inspection methods. This program uses an alternative to the risk-informed process described in NRC-approved EPRI-TR-112657. The implementation strategy, modified as described in its submittal, satisfies the guidelines established in RG 1.174 and is consistent with the guidance provided in RG 1.178. Therefore, the continued use of this alternative during the first period of the fifth interval will continue to provide an acceptable level of quality and safety.

Relief Request 17-GO-001 provides an acceptable level of quality and safety because the EPRI Technical Report No. 3002007626, as referenced in the request, determined the RPV threads in flange examination could safely be eliminated. Duke has demonstrated that the deterministic stress analysis and flaw tolerance evaluation in the EPRI Report are bounding for the RPV flange. Therefore, continued use of this relief request for the first period of the fifth interval of Unit 1 continues to provide an acceptable level of quality and safety.

Relief Request 18-GO-001 provides reasonable assurance of the structural integrity and leak tightness of the subject welds because the proposed RMS error provides reasonable assurance that the ultrasonic examination has been qualified to measure the depth of flaws with a reasonable accuracy and Duke uses qualified ultrasonic examination techniques in accordance with Code Cases N-695-1 and N- 696-1. Therefore, continued use of this relief request for the first period of the fifth interval of Unit 1 continues to provide an acceptable level of quality and safety.

Relief Request 19-GO-001 continues to provide reasonable assurance of the structural integrity and leak tightness based on the studies provided as referenced in the relief request. There is sufficient technical basis for the use of encoded PAUT in lieu of RT for repair/replacement inspection of the ferritic steel or austenitic stainless steel piping welds. The encoded PAUT, as compared to RT, was shown to be an effective technique for both detection and characterization of fabrication flaws in the repaired/replaced ferritic steel or austenitic stainless steel piping welds. Therefore, continued use of this relief request for the first period of the fifth interval of Unit 1 continues to provide an acceptable level of quality and safety.