ML26026A187
| ML26026A187 | |
| Person / Time | |
|---|---|
| Site: | Calvert Cliffs, Dresden, Peach Bottom, Nine Mile Point, Byron, Braidwood, Limerick, Ginna, Clinton, Quad Cities, FitzPatrick, LaSalle  |
| Issue date: | 01/26/2026 |
| From: | Scott Wall Plant Licensing Branch III |
| To: | Jonathan Brown Constellation Energy Generation |
| Wall, SP | |
| References | |
| EPID L-2025-LLR-0060 | |
| Download: ML26026A187 (0) | |
Text
From:
Scott Wall To:
Brown, Jesse S: (Constellation Nuclear)
Cc:
Knowles, Justin W:(Constellation Nuclear)
Subject:
Final RAI - Constellation Energy Generation, LLC - Fleet Request - Proposed Alternative for Reactor Vessel Close Stud Examinations (L-2025-LLR-0060)
Date:
Monday, January 26, 2026 11:43:51 AM
Dear Mr. Brown,
By letter dated June 16, 2025 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML25167A176), Constellation Energy Generation, LLC (CEG, the licensee) requested to a proposed alternative to the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code, Section Xl (BVP Code), at the following units:
Braidwood Station, Unit 1 Byron Station, Units 1 and 2 Calvert Cliffs Nuclear Power Plant, Units 1 and 2 Clinton Power Station, Unit 1 James A. FitzPatrick Nuclear Power Plant LaSalle County Station, Units 1 and 2 Limerick Generating Station, Units 1 and 2 Nine Mile Point Nuclear Station, Units 1 and 2 Peach Bottom Atomic Power Station, Units 2 and 3
Specifically, the proposed alternative requests to extend the inspection interval for the ASME Code,Section XI, Table IWB-2500-1, Examination Category B-G-1, Item Number B6.20 examinations for the remainder of the currently licensed operating periods and through the Sixth Inservice Inspection (ISI) interval for Peach Bottom Atomic Power Station. The proposed alternative is also requested for the remainder of the currently licensed operating periods for Braidwood Station, Unit 1, Byron Station, Units 1 and 2, Calvert Cliffs Nuclear Power Plant, Units 1 and 2, Clinton Power Station, Unit 1, James A. FitzPatrick Nuclear Power Plant, LaSalle County Station, Units 1 and 2, Limerick Generating Station, Units 1 and 2, and Nine Mile Point Nuclear Station, Units 1 and 2, and through the Sixth ISI interval for Peach Bottom Atomic Power Station, Units 2 and 3.
The U.S. Nuclear Regulatory Commission (NRC) staff has reviewed the submittal and determined that additional information is needed to complete its review. The specific question is found in the enclosed request for additional information (RAI). On January 26, 2026, the CEG staff indicated that a response to the RAIs would be provided by February 27, 2026.
If you have questions, please contact me at 301-415-2855 or via e mail at Scott.Wall@nrc.gov.
Scott P. Wall Senior Project Manager Plant Licensing Branch III Division of Operating Reactor Licensing
Office of Nuclear Reactor Regulation 301.415.2855 Scott.Wall@nrc.gov
Docket Nos.: STN 50-456, STN 50-454, STN 50-455, 50-317, 50-318, 50-461, 50-333, 50-373, 50-374, 50-352, 50-353, 50-220, 50-410, 50-277, and 50-278
Enclosure:
Request for Additional Information
cc: Listserv
RAI (Reactor Vessel Close Stud Examinations)
REQUEST FOR ADDITIONAL INFORMATION
ALTERNATIVE REQUEST FOR REACTOR VESSEL CLOSURE STUD EXAMINATIONS
CONSTELLATION ENERGY GENERATION, LLC
BRAIDWOOD STATION, UNIT 1
BYRON STATION, UNITS 1 AND 2
CALVERT CLIFFS NUCLEAR POWER PLANT, UNITS 1 AND 2
CLINTON POWER STATION, UNIT 1
JAMES A. FITZPATRICK NUCLEAR POWER PLANT
LASALLE COUNTY STATION, UNITS 1 AND 2
LIMERICK GENERATING STATION, UNITS 1 AND 2
NINE MILE POINT NUCLEAR STATION, UNITS 1 AND 2
PEACH BOTTOM ATOMIC POWER STATION, UNITS 2 AND 3
DOCKETNOS.STN 50-456, STN 50-454, STN 50-455, 50-317, 50-318, 50-461,
50-333, 50-373, 50-374, 50-352, 50-353, 50-220, 50-410, 50-277, AND 50-278
By letter dated June 16, 2025 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML25167A176), Constellation Energy Generation, LLC (CEG, the licensee) requested to a proposed alternative to the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code, Section Xl (BVP Code), at the following units:
Braidwood Station, Unit 1 Byron Station, Units 1 and 2 Calvert Cliffs Nuclear Power Plant, Units 1 and 2 Clinton Power Station, Unit 1 James A. FitzPatrick Nuclear Power Plant LaSalle County Station, Units 1 and 2 Limerick Generating Station, Units 1 and 2 Nine Mile Point Nuclear Station, Units 1 and 2 Peach Bottom Atomic Power Station, Units 2 and 3
Specifically, the proposed alternative requests to extend the inspection interval for the ASME Code,Section XI, Table IWB-2500-1, Examination Category B-G-1, Item Number B6.20 examinations for the remainder of the currently licensed operating periods and through the Sixth Inservice Inspection (ISI) interval for Peach Bottom Atomic Power Station. The proposed alternative is also requested for the remainder of the currently licensed operating periods for Braidwood Station, Unit 1, Byron Station, Units 1 and 2, Calvert Cliffs Nuclear Power Plant, Units 1 and 2, Clinton Power Station, Unit 1, James A. FitzPatrick Nuclear Power Plant, LaSalle County Station, Units 1 and 2, Limerick Generating Station, Units 1 and 2, and Nine Mile Point Nuclear Station, Units 1 and 2, and through the Sixth ISI interval for Peach Bottom Atomic Power Station, Units 2 and 3.
The U.S. Nuclear Regulatory Commission (NRC) staff determined that the following information is needed to complete its review.
Vessels and Internals Testing Branch (NVIB) Request for Additional Information (RAI)
NVIB-RAI-1
Regulatory Requirements
The NRC regulations in 10 CFR 50.55a(z), Alternatives to codes and standards requirements, state the following:
Alternatives to the requirements of paragraphs (b) through (h) of this section or portions thereof may be used when authorized by the Director, Office of Nuclear Reactor Regulation. A proposed alternative must be submitted and authorized prior to implementation. The applicant or licensee must demonstrate that:
(1) Acceptable level of quality and safety. The proposed alternative would provide an acceptable level of quality and safety; or
(2) Hardship without a compensating increase in quality and safety.
Compliance with the specified requirements of this section would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety.
Issue
The submittal states that as part of the proposed performance monitoring plan, the ASME Code,Section XI ISI examinations on the Reactor Pressure Vessel (RPV) closure studs at the following units of the CEG fleet - Braidwood Unit 2, Dresden Units 2 and 3, Ginna, and Quad Cities Units 1 and 2 - will continue to be performed.
There is no information in the submittal regarding the timing of the performance monitoring examinations of the RPVH closure studs of the above CEG fleet units with regard to how they map to the proposed extended alternative periods (Table 2 of the enclosure to the submittal). The NRC staff needs this information to determine whether the proposed performance monitoring examinations would provide sufficient distribution of examination data over the proposed extended alternative periods to support reasonable assurance of continued adequate structural integrity of the subject RPVH closure studs.
The NRC staff noted that CEG provided a graphical representation of the timing of the performance monitoring examinations for the steam generator alternative examination request submitted to the NRC by letters dated October 10, 2023, and October 11, 2023 (ML23283A003 and ML23284A259, respectfully). The NRC staff approved this request by letter dated July 23, 2024 (ML24179A326).
Request
Clarify the timing of the ASME Code Section XI examinations of the RPV closure studs of the CEG fleet units proposed for performance monitoring relative to the proposed extended alternative periods, to demonstrate that sufficient distribution of examination data would be obtained over those periods to support reasonable assurance of continued adequate structural integrity of the subject RPV closure studs.