ML21342A090

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Summary of December 7, 2021, Public Meeting with Duke Energy Carolinas, LLC, Regarding Pre-Application Meeting to Discuss Reactor Vessel Closure Head Nozzle Repair for Catawba Nuclear Station, Unit 2
ML21342A090
Person / Time
Site: Catawba Duke Energy icon.png
Issue date: 12/14/2021
From: Stone Z
NRC/NRR/DORL/LPL2-1
To:
Zack Stone (301) 415-0615
References
EPID L-2021-LRM-0110
Download: ML21342A090 (4)


Text

December 14, 2021 LICENSEE:

Duke Energy Carolinas, LLC FACILITY:

Catawba Nuclear Station, Unit 2

SUBJECT:

SUMMARY

OF DECEMBER 7, 2021, PUBLIC MEETING WITH DUKE ENERGY CAROLINAS, LLC, REGARDING PRE-APPLICATION MEETING TO DISCUSS REACTOR VESSEL CLOSURE HEAD NOZZLE REPAIR (EPID L-2021-LRM-0110)

On December 7, 2021, an Observation public meeting was held between the U.S. Nuclear Regulatory Commission (NRC) and representatives of Duke Energy Carolinas, LLC (Duke Energy, the licensee). The purpose of the meeting was for Duke Energy to discuss a proposed relief request, for Catawba Nuclear Station, Unit 2, to extend the NRC-approved period of time beyond the current cycle (Cycle 25) of the weld overlay performed on the reactor vessel closure head (RVCH) penetration #74.

The meeting notice and agenda, dated October 25, 2021, are available in the Agencywide Documents Access and Management System (ADAMS) at Accession No. ML21298A035, and the licensees presentation is available in ADAMS as Accession No. ML21336A142. A list of the meetings attendees is provided as an enclosure to this letter.

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Background===

During the Catawba Nuclear Station, Unit 2, refueling outage, the licensee identified a relevant indication in the RVCH penetration #74 J-groove weld. Based on the licensees assessment and examination of the indication, the licensee determined that the repair of the J-groove weld was required during the refueling outage. By letter dated April 23, 2021 (ADAMS Accession No. ML21113A215), as supplemented by letter dated April 24, 2021 (ADAMS Accession No. ML21114A000), the licensee proposed to repair the J-grove weld of RVCH penetration #74 using an embedded flaw repair process as an alternative to the defect removal and weld repair provisions of American Society of Mechanical Engineers (ASME)Section XI, IWA-4000 and ASME Section III, NB-4450. On April 24, 2021 (ADAMS Accession No. ML21117A129), the U.S. Nuclear Regulatory Commission (NRC) verbally authorized the proposed alternative RA-21-0145 for one cycle of operation at Catawba Nuclear Station, Unit 2, until the end of Cycle 25 that is scheduled to end in the fall 2022. On September 20, 2021 (ADAMS Accession No. ML21253A082), the NRC authorized the use of proposed alternative RA-21-0145 at Catawba Nuclear Station, Unit 2, for one cycle of operation that will end in fall 2022.

Teleconference During the teleconference, Duke Energy discussed the presentation as written.

Duke Energy is proposing to use the RVCH penetration #74 embedded flaw repair (EFR) through the remaining licensed plant life (December 5, 2043) as an alternative to the defect removal and weld repair provisions of the ASME code. Duke Energy is proposing to submit a site-specific fracture mechanics analysis to justify the proposed duration is bounded by the service life of the repair.

NRC Questions to Duke Energy The NRC staff stated that the site-specific fracture mechanics analysis should contain sufficient detail for NRC staff to perform an independent assessment to conclude the alternative provides an acceptable level of quality and safety.

The NRC staff questioned if the licensee requested approval date of September 10, 2022, was adequate for outage planning purposes because the current approval expires at the end of Cycle 25, which is scheduled to end in the fall of 2022. The licensee stated they would follow up with the NRC staff.

Public Questions to NRC No members of the public were in attendance.

Closing No regulatory decisions or commitments were made during the meeting. Public Meeting Feedback forms were available, but no comments were received.

Please direct any inquiries to me at 301-415-0615, or Zackary.stone@nrc.gov.

Zackary R. Stone, Project Manager Plant Licensing Branch, II-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-414

Enclosures:

List of Attendees cc: Listserv Zackary R.

Stone Digitally signed by Zackary R. Stone Date: 2021.12.14 13:47:37 -05'00'

Enclosure LIST OF ATTENDEES DECEMBER 7, 2021, PUBLIC MEETING WITH DUKE ENERGY CAROLINAS REGARDING A PRE-APPLICATION MEETING TO DISCUSS REACTOR VESSEL CLOSURE HEAD NOZZLE REPAIR CATAWBA NUCLEAR STATION, UNIT 2 Nuclear Regulatory Commission Staff Zackary Stone Shawn Williams Michael Markley Ali Rezai Duke Energy Carolinas/Westinghouse Participants Lee Grzeck Chet Sigmon Mark Honeycutt Scott Karriker Sherry Andrews Anees Udyawar Steve Marlette Maria Rizzilli Geoffrey Loy Stephen Feder Jason Pulliam David Burton Wayne Gibson Mandy Hare Lisa Gerken Lynn Patterson

Package: ML21342A131 Meeting Summary: ML21342A090 Meeting Notice: ML21298A03 Handouts: ML21336A142 OFFICE NRR/DORL/LPL2-1/PM NRR/DORL/LPL2-1/LA NRR/DNRL/NPHP/BC NAME ZStone KGoldstein MMitchell DATE 12/07/2021 12/08/2021 12/07/2021 OFFICE NRR/DORL/LPL2-1/BC NRR/DORL/LPL2-1/PM NAME MMarkley ZStone DATE 12/14/2021 12/14/2021