ML25113A282
| ML25113A282 | |
| Person / Time | |
|---|---|
| Site: | Brunswick  |
| Issue date: | 04/17/2025 |
| From: | Natreon Jordan Plant Licensing Branch II |
| To: | Duc J, Treadway R Duke Energy Progress |
| Purnell, B | |
| References | |
| EPID L-2025-LLR-0038 | |
| Download: ML25113A282 (3) | |
Text
From:
Natreon Jordan To:
Joshua.Duc@duke-energy.com; Treadway, Ryan I Cc:
Subject:
FINAL Brunswick U1 RAI Reducer Alternative Date:
Thursday, April 17, 2025 11:46:42 AM Attachments:
FINAL Brunswick U1 RAI Reducer Alternative.docx Good Morning,
On April 14, 2025, the U.S. Nuclear Regulatory Commission (NRC) staff issued draft Requests for Additional Information (RAIs) to Duke Energy Progress, LLC (the licensee). The RAIs are related to the licensees submittal, dated March 21, 2025 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML25080A235), requesting a proposed alternative to certain requirements in Title 10 of the Code of Federal Regulations (10 CFR) Section 50.55a, Codes and standards, for Brunswick Steam Electric Plant, Unit 1. Specifically, the licensee proposed to use subarticle NB-3200, Design by Analysis, of the 2007 Edition with 2008 Addenda of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (ASME Code),Section III, for demonstration of the structural integrity and acceptance of the through-wall flaw in the reducer small end transition zone of service water system until the next scheduled refueling outage without repair or replacement.
To monitor the flaw growth and leakage, the licensee proposed frequent periodic examinations of the degraded reducer.
A clarification call was held on April 16, 2025, between the licensee and NRC staff to ensure that the information requested was clearly understood. At the conclusion of the call, the licensee specified that no additional clarification regarding the RAIs was necessary. A publicly available version of the FINAL RAIs (with the term DRAFT removed) will be placed in the NRCs Agencywide Documents Access and Management System (ADAMS). The NRC staff request your response to the RAIs within 30 days of the date of this email. If you do not believe that you can meet the response date, please provide an acceptable alternate date and justification for extending the response date.
If you have any questions, please contact either Blake Purnell at Blake.Purnell@nrc.gov or myself at Natreon.Jordan@nrc.gov.
- Thanks,
-Nate
REQUEST FOR ADDITIONAL INFORMATION PROPOSED ALTERNATIVE FOR ACCEPTANCE OF THROUGH-WALL FLAW IN A REDUCER SMALL END TRANSITION ZONE DUKE ENERGY PROGRESS, LLC BRUNSWICK STEAM ELECTRIC PLANT, UNIT 1 DOCKET NO. 50-325 By letter dated March 21, 2025 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML25080A235), Duke Energy Progress, LLC (the licensee) submitted a request for a proposed alternative to certain requirements in Title 10 of the Code of Federal Regulations (10 CFR) Section 50.55a, Codes and standards, for Brunswick Steam Electric Plant, Unit 1. Specifically, the licensee proposed to use subarticle NB-3200, Design by Analysis, of the 2007 Edition with 2008 Addenda of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (ASME Code),Section III, for demonstration of the structural integrity and acceptance of the through-wall flaw in the reducer small end transition zone of service water system until the next scheduled refueling outage without repair or replacement. To monitor the flaw growth and leakage, the licensee proposed frequent periodic examinations of the degraded reducer.
Pursuant to 10 CFR 50.55a(g)(4), ASME Code Class 1, 2, and 3 components must meet the requirements, except the design and access provisions and the pre-service examination requirements, set forth in Section XI of editions and addenda of the ASME Code that are incorporated by reference in 10 CFR 50.55a(a)(1)(ii). The regulations in 10 CFR 50.55a(z) state, in part, that alternatives to the requirements in paragraphs (b) through (h) of 10 CFR 50.55a may be authorized by the U.S. Nuclear Regulatory Commission (NRC) if the licensee demonstrates that: (1) the proposed alternative provides an acceptable level of quality and safety, or (2) compliance with the specified requirements would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety.
The NRC staff has reviewed the application and determined that the information below is needed to complete its review.
- 1. Confirm that a flooding analysis to evaluate the impact of the leakage at the allowable leak rate on the safety-related structures, systems, and components in the room and/or vicinity of the leaking pipe has been completed and summarize its conclusions. Provide a leak rate limit (or corresponding hole size), based on the flooding analysis, beyond which corrective action (e.g., repair or replacement) must be taken or confirm that this limit would correspond to a hole size larger than the 10-inch by 10-inch hole considered in the structural integrity evaluation.
- 2. Section 1.0 of Attachment 3 to the proposed alternative states that the interior surface of the degraded pipe has a cement lining.
- a. Discuss whether the cement lining provides any structural support of pipe loads.
- b. Discuss whether the cement lining is modeled in the finite element model or provide justification for not modeling.
- c. Discuss whether the weight of cement lining is included in the deadweight of pipe as part of the stress analysis or provide justification for not including.
- d. Provide the average thickness of the cement lining.