ML21314A121
| ML21314A121 | |
| Person / Time | |
|---|---|
| Site: | Arkansas Nuclear  |
| Issue date: | 11/09/2021 |
| From: | Thomas Wengert Plant Licensing Branch IV |
| To: | Keele R Entergy Operations |
| Wengert T | |
| References | |
| EPID L-2021-LLR-0084 | |
| Download: ML21314A121 (4) | |
Text
1 From:
Wengert, Thomas Sent:
Tuesday, November 09, 2021 3:03 PM To:
Keele Jr, Riley D Cc:
Clark, Robert; Dixon-Herrity, Jennifer; Mitchell, Matthew
Subject:
Arkansas Nuclear One, Unit 2 - Verbal Authorization of Relief Request ANO2-RR-21-002 (EPID L-2021-LLR-0084)
Attachments:
Verbal Authorization of Relief Request ANO2-RR-21-002 dated 11-9-21.pdf By telephone conversation on November 9, 2021, the U.S. Nuclear Regulatory Commission (NRC) staff provided a verbal authorization to Entergy Operations, Inc. (the licensee) for the proposed alternative ANO2-RR-21-002 for Arkansas Nuclear One, Unit 2 (ANO-2). By letter dated November 5, 2021 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML21309A007), as supplemented by letter dated November 7, 2021 (ADAMS Accession No. ML21312A017),
the licensee submitted proposed alternative ANO2-RR-21-002 for Arkansas Nuclear One, Unit 2 (ANO-2). In ANO2-RR-21-002, the licensee stated that a flaw located in Reactor Vessel Closure Head Penetration Nozzle
- 46 was determined to be unacceptable based on requirements of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code). In order to address the flaw, the licensee stated it will perform a half-nozzle repair of Nozzle #46. The specific ASME Code requirements for which the licensee has requested NRC approval of an alternative are identified in the licensees November 5, 2021 letter. The licensee made this request pursuant to Title 10 of the Code of Federal Regulations (10 CFR) 50.55a(z)(1),
Acceptable level of quality and safety, to ensure structural integrity of Nozzle #46 for one cycle of operation at ANO-2.
The NRC staffs evaluation and verbal authorization is repeated in the attachment to this e-mail.
The following NRC and licensee personnel participated in the conference call:
NRC Jennifer Dixon-Herrity - Chief, Plant Licensing Branch IV (LPL4)
Matthew Mitchell - Chief, Piping and Head Penetrations Branch (NPHP)
Nick Taylor - Chief, Region 4, Engineering Branch 2 Fred Sanchez - Sr. Project Engineer, Region 4, Division of Reactor Projects Branch D (DRP D)
Jay Collins - Senior Materials Engineer (NPHP)
Seung Min - Materials Engineer (NPHP)
Russ Bywater - ANO Senior Resident Inspector Tom Wengert - Senior Project Manager (LPL4)
Entergy Ron Gaston Phil Couture Riley Keele Bob Clark Barry Davis Grant Flynn Joe Weicks Andy Nettles Blake Hogue Justin Morris Melissa Franco Andy Justice Joe DeVault
2 Robert Allen
Please contact me if you have any questions.
Tom Wengert Project Manager - Arkansas Nuclear One U.S. Nuclear Regulatory Commission Division of Operating Reactor Licensing Plant Licensing Branch IV Thomas.Wengert@nrc.gov
1 VERBAL AUTHORIZATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION FOR PROPOSED ALTERNATIVE ANO2-RR-21-002 HALF-NOZZLE REPAIR OF REACTOR VESSEL CLOSURE HEAD PENETRATION NOZZLE NUMBER 46 ENTERGY OPERATIONS, INC.
ARKANSAS NUCLEAR ONE, UNIT 2 DOCKET NO. 50-368 NOVEMBER 9, 2021 Technical Evaluation Read by Matthew Mitchell, Branch Chief, Piping and Head Penetrations Branch, Division of New and Renewed Licenses, Office of Nuclear Reactor Regulation By letter dated November 5, 2021 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML21309A007), as supplemented by letter dated November 7, 2021 (ADAMS Accession No. ML21312A017), Entergy Operations, Inc. (the licensee) submitted proposed alternative ANO2-RR-21-002 for Arkansas Nuclear One, Unit 2 (ANO-2). In ANO2-RR-21-002, the licensee stated that a flaw located in Reactor Vessel Closure Head Penetration Nozzle #46 was determined to be unacceptable based on requirements of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code). In order to address the flaw, the licensee stated it will perform a half-nozzle repair of Nozzle #46.
The specific ASME Code requirements for which the licensee has requested Nuclear Regulatory Commission (NRC) approval of an alternative are identified in the licensees November 5, 2021 letter. The licensee made this request in accordance with Title 10 of the Code of Federal Regulations (10 CFR) 50.55a(z)(1), Acceptable level of quality and safety, to ensure structural integrity of Nozzle #46 for one cycle of operation at ANO-2.
The U.S. Nuclear Regulatory Commission (NRC) staff reviewed: (1) licensees proposed repair methodology, including welding methods and nondestructive examination methods and acceptance criteria; and (2) the licensees qualitative flaw analyses of the flaw in the j-groove weld and anomalies at the upper and lower triple points created by the repair. The NRC staff finds that the proposed modifications to nondestructive evaluation methods, examination areas and acceptance criteria are acceptable because the proposed alternative examinations will ensure the quality and integrity of the as-installed half-nozzle repair. The NRC staff finds that the Inside Diameter Temper Bead welding method, which will be used in the fabrication of the half-nozzle repair, has been demonstrated to maintain the structural integrity of the reactor coolant pressure boundary. The NRC staff also finds that the licensees qualitative flaw analyses provide reasonable assurance that the integrity of the Reactor Vessel Closure Head and Nozzle #46 will be maintained for one cycle of operation.
Therefore, the NRC staff finds that the licensees proposed alternative provides reasonable assurance of the structural integrity of the Reactor Vessel Closure Head and repaired penetration Nozzle #46 for the next operating cycle at ANO-2. As such, the NRC staff concludes the licensees proposed alternative provides an acceptable level of quality and safety in accordance with 10 CFR 50.55a(z)(1).
2 NRC Staff Conclusion Read by Jennifer Dixon-Herrity, Chief of Plant Licensing Branch IV, Division of Operating Reactor Licensing, Office of Nuclear Reactor Regulation As Chief of Plant Licensing Branch IV, I concur with the Piping and Head Penetrations Branchs determinations.
The NRC staff concludes that proposed alternative ANO2-RR-21-002 will provide an acceptable level of quality and safety for the Reactor Vessel Closure Head and repaired penetration Nozzle
- 46. Accordingly, the NRC staff concludes that the licensee has adequately addressed all of the regulatory requirements set forth in 10 CFR 50.55a(z)(1) and is in compliance with the requirements of the ASME Code,Section XI. Therefore, as of November 9, 2021, the NRC authorizes proposed alternative ANO2-RR-21-002 for one cycle of operation at ANO-2, which is scheduled to end in the spring of 2023.
All other requirements of the ASME Code or 10 CFR 50.55a for which an alternative was not specifically requested and authorized by the NRC staff remain applicable, including the third party review by the Authorized Nuclear Inservice Inspector.
This verbal authorization does not preclude the NRC staff from requesting additional clarification information regarding the licensees proposed alternative while preparing the subsequent written safety evaluation.