ML24296A065
| ML24296A065 | |
| Person / Time | |
|---|---|
| Site: | Arkansas Nuclear  |
| Issue date: | 10/22/2024 |
| From: | Mahesh Chawla NRC/NRR/DORL/LPL4 |
| To: | Keele R Entergy Nuclear Operations |
| References | |
| L-2024-LLR-0065 | |
| Download: ML24296A065 (5) | |
Text
From:
Mahesh Chawla Sent:
Tuesday, October 22, 2024 10:04 AM To:
Keele Jr, Riley D Cc:
Jennie Rankin; Matthew Mitchell; Jay Collins; Omar Khan NRR; Karen Sida; John Dixon; Alfred Sanchez; Brian Tindell; Timothy DeBey; Erin Tinger
Subject:
RE: Arkansas Nuclear One, Unit 2 - Verbal Authorization of Relief Request ANO2-RR (EPID L-2024-LLR-0065)
Attachments:
ANO-2 Verbal Script Half-Nozzle Repair CEDM 71.docx By telephone conversation on October 21, 2024, the U.S. Nuclear Regulatory Commission (NRC) staff provided a verbal authorization to Entergy Operations, Inc. (the licensee) for the proposed alternative ANO2-RR-24-001 for Arkansas Nuclear One, Unit 2 (ANO-2). By letter dated October 21, 2024 (Agencywide Documents Access and Management System (ADAMS)
Package Accession No. ML24295A119), the licensee submitted proposed alternative ANO2-RR-24-001 for Arkansas Nuclear One, Unit 2 (ANO-2). In ANO2-RR-24-001, the licensee stated that a flaw located in Reactor Vessel Closure Head Penetration Nozzle #71 was determined to be unacceptable based on requirements of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code). To address the flaw, the licensee stated it will perform a half-nozzle repair of Nozzle #71. The specific ASME Code requirements for which the licensee has requested NRC approval of an alternative are identified in the licensees letter dated October 21, 2024. 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 #71 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 Jennivine Rankin - Chief, Plant Licensing Branch IV (LPL4)
Matthew Mitchell - Chief, Piping and Head Penetrations Branch (NPHP)
Jay Collins - Senior Materials Engineer, NPHP Omar Khan - Materials Engineer, NPHP Mahesh Chawla - Project Manager, LPL4 Entergy Riley Keele Manager, Regulatory Assurance - ANO Bob Clark Senior Licensing Specialist - ANO Gary Sullins Engineering Director - ANO Frank Rutledge Project Manager - Entergy Andy Nettles Central Programs Senior Lead Engineer - Entergy Jason Oliver Superintendent Project Management - Entergy Ed Blackard Responsible Engineer - ANO Josh Jones Operations Director - ANO Chris Johnson Engineering Supervisor - ANO Hannah McDaniel Engineer - GGNS Please contact me if you have any questions.
Mahesh(Mac) Chawla, Project Manager Licensing Branch LPL4 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Phone: (301) 415-8371 Email: Mahesh.Chawla@nrc.gov OFFICE DORL/LPL4/PM DORL/LPL4/BC NAME MChawla JRankin DATE 10/22/24 10/22/24
Hearing Identifier:
NRR_DRMA Email Number:
2627 Mail Envelope Properties (SJ0PR09MB1040513B47D509E0F49DCA5E5F14C2)
Subject:
RE Arkansas Nuclear One, Unit 2 - Verbal Authorization of Relief Request ANO2-RR (EPID L-2024-LLR-0065)
Sent Date:
10/22/2024 10:04:10 AM Received Date:
10/22/2024 10:04:00 AM From:
Mahesh Chawla Created By:
Mahesh.Chawla@nrc.gov Recipients:
"Jennie Rankin" <Jennivine.Rankin@nrc.gov>
Tracking Status: None "Matthew Mitchell" <Matthew.Mitchell@nrc.gov>
Tracking Status: None "Jay Collins" <Jay.Collins@nrc.gov>
Tracking Status: None "Omar Khan NRR" <Omar.Khan2@nrc.gov>
Tracking Status: None "Karen Sida" <Karen.Sida@nrc.gov>
Tracking Status: None "John Dixon" <John.Dixon@nrc.gov>
Tracking Status: None "Alfred Sanchez" <Alfred.Sanchez@nrc.gov>
Tracking Status: None "Brian Tindell" <Brian.Tindell@nrc.gov>
Tracking Status: None "Timothy DeBey" <Timothy.DeBey@nrc.gov>
Tracking Status: None "Erin Tinger" <erin.tinger@nrc.gov>
Tracking Status: None "Keele Jr, Riley D" <rkeele@entergy.com>
Tracking Status: None Post Office:
SJ0PR09MB10405.namprd09.prod.outlook.com Files Size Date & Time MESSAGE 2504 10/22/2024 10:04:00 AM ANO-2 Verbal Script Half-Nozzle Repair CEDM 71.docx 33013 Options Priority:
Normal Return Notification:
No Reply Requested:
No Sensitivity:
Normal Expiration Date:
VERBAL AUTHORIZATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION FOR PROPOSED ALTERNATIVE ANO2-RR-24-001 HALF-NOZZLE REPAIR OF REACTOR VESSEL CLOSURE HEAD PENETRATION NOZZLE NUMBER 71 ENTERGY OPERATIONS, INC.
ARKANSAS NUCLEAR ONE, UNIT 2 DOCKET NO. 50-368 OCTOBER 21, 2024 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 October 21, 2024 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML24295A119), Entergy Operations, Inc. (the licensee) submitted proposed alternative ANO2-RR-24-001 for Arkansas Nuclear One, Unit 2 (ANO-2). In ANO2-RR-24-001, the licensee stated that a flaw located in Reactor Vessel Closure Head Penetration Nozzle #71 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 Penetration Nozzle #71. The specific ASME Code requirements for which the licensee has requested Nuclear Regulatory Commission (NRC) approval of an alternative are identified in the licensees October 21, 2024, 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 Penetration Nozzle #71 for one cycle of operation at ANO-2.
The NRC staff reviewed: (1) licensees proposed repair methodology, including welding methods and nondestructive examination methods and acceptance criteria; (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 and (3) the licensees analysis of a hypothetical flaw to address not performing stress mitigation of the remaining Alloy 600 penetration nozzle. The NRC staff finds that the proposed modifications to the 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 Penetration Nozzle #71 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 #71 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).
NRC Staff Conclusion Read by Jennie Rankin, 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-24-001 will provide an acceptable level of quality and safety for the Reactor Vessel Closure Head and repaired Penetration Nozzle
- 71. 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 October 21, 2024, the NRC authorizes proposed alternative ANO2-RR-24-001 for one cycle of operation at ANO-2, which is scheduled to end in the Spring of 2026.
All other requirements of the ASME Code and 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.