RS-22-036, Supplemental Information - Proposed Alternative for Examination of Pressurizer Circumferential and Longitudinal Shell-to-Head Welds and Nozzle-to-Vessel Welds

Supplemental Information - Proposed Alternative for Examination of Pressurizer Circumferential and Longitudinal Shell-to-Head Welds and Nozzle-to-Vessel Welds

ML22069A580
Person / Time
Site:	Byron, Braidwood
Issue date:	03/10/2022
From:	David Gudger Constellation Energy Generation
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
RS-22-036
Download: ML22069A580 (5)

Text

200 Exelon Way Kennett Square, PA 19348 www.constellation.com 10 CFR 50.55a RS-22-036 March 10, 2022 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555-0001 Braidwood Station, Units 1 and 2 Renewed Facility Operating License Nos. NPF-72 and NPF-77 NRC Docket Nos. STN 50-456 and STN 50-457 Byron Station, Units 1 and 2 Renewed Facility Operating License Nos. NPF-37 and NPF-66 NRC Docket Nos. STN 50-454 and STN 50-455

Subject:

Supplemental Information - Proposed Alternative for Examination of Pressurizer Circumferential and Longitudinal Shell-to-Head Welds and Nozzle-to-Vessel Welds

References:

1) Letter from D. Gudger (Exelon Generation Company, LLC) to U.S.

Nuclear Regulatory Commission, Proposed Alternative for Examination of Pressurizer Circumferential and Longitudinal Shell-to-Head Welds and Nozzle-to-Vessel Welds, dated May 12, 2021 (ML21133A297)

2) Email from A. Mayer (U.S. Nuclear Regulatory Commission) to T. Loomis (Exelon Generation Company, LLC), Calvert Cliffs Nuclear Power Plant, Units 1 and 2 - Request for Additional Information re: Proposed Alternative for Pressurizer Circumferential and Longitudinal Shell-to-Head Welds and Nozzle-to-Vessel Welds (EPID L-2021-LLR-0037), dated October 13, 2021 (ML21287A032)

3) Letter from D. Helker (Exelon Generation Company, LLC) to U.S. Nuclear Regulatory Commission, Response to Request for Additional Information

- Proposed Alternative for Examination of Pressurizer Circumferential and Longitudinal Shell-to-Head Welds and Nozzle-to-Vessel Welds, dated November 16, 2021 (ML21320A242)

In the Reference 1 letter, Constellation Energy Generation, LLC (CEG) requested relief from the examination of pressurizer circumferential and longitudinal shell-to-head welds and nozzle-to-vessel welds for Braidwood Station, Units 1 and 2 and Byron Station, Units 1 and

2. Based on concerns identified by the U.S. Nuclear Regulatory Commission, CEG has developed a performance monitoring plan for the welds identified in this proposed

Supplemental Information - Proposed Alternative for Examination of Pressurizer Circumferential and Longitudinal Shell-to-Head Welds and Nozzle-to-Vessel Welds March 10, 2022 Page 2 alternative. As shown in Table 1 of Reference 1, Byron Station, Unit 2 requests the greatest length of time until the next inspection. Category B-B requested an extension of 32.1 years and Category B-D requested an extension of 27.6 years. As part of the performance monitoring plan, CEG will examine one Examination Category B-B, Item B2.11 shell-to-head weld and one Category B-D, B3.110 nozzle-to-vessel weld from the Byron Station, Unit 2 to the maximum extent possible. The components available for examination are provided in the table below for reference. Due to the limited examination volume (1 foot of 1 weld) no Category B-B, Item B2.12 longitudinal welds will be included in the sampling plan. The required examination will be completed by the end of 2034 to ensure that no more than 20 years elapses between the performance of an ASME XI examination for the Category B-B and B-D components at Byron Station, Unit 2. Due to similarities in design and operation strategies between Byron and Braidwood, this sampling plan is applicable to Byron Units 1 and 2 as well as Braidwood Units 1 and 2. Any unacceptable indications identified during these examinations will be evaluated as required by ASME Section XI and the corrective action program. Unacceptable indications may result in an accelerated examination schedule for the components covered by the alternative.

ASME ASME Unit Component ID Component Description Category Item 2 B-B B2.11 2RY-01-S/PC-01 Shell - Bottom Head 2 B-B B2.11 2RY-01-S/PC-05 Shell - Upper Head 2 B-B B2.12 2RY-01-S/PL-01 Lower Longitudinal Weld 2 B-B B2.12 2RY-01-S/PL-04 Upper Longitudinal Weld 2 B-D B3.110 2RY-01-S/PN-01 Surge Nozzle 2 B-D B3.110 2RY-01-S/PN-02 Spray Nozzle 2 B-D B3.110 2RY-01-S/PN-03 Relief Nozzle 2 B-D B3.110 2RY-01-S/PN-04 Safety Nozzle 2 B-D B3.110 2RY-01-S/PN-05 Safety Nozzle 2 B-D B3.110 2RY-01-S/PN-06 Safety Nozzle A regulatory commitment is contained in the attachment.

Should you have any questions concerning this matter, please contact Tom Loomis at (610) 765-5510.

Respectfully, David T. Gudger Sr. Manager - Licensing Constellation Energy Generation, LLC

Attachment:

Summary of Commitments

Supplemental Information - Proposed Alternative for Examination of Pressurizer Circumferential and Longitudinal Shell-to-Head Welds and Nozzle-to-Vessel Welds March 10, 2022 Page 3 cc: Regional Administrator - NRC Region III NRC Senior Resident Inspector - Braidwood Station NRC Senior Resident Inspector - Byron Station NRC Project Manager - Braidwood Station NRC Project Manager - Byron Station Illinois Emergency Management Agency - Division of Nuclear Safety

Attachment Summary of Commitments

Attachment Summary of Commitments The following table identifies commitments made in this document. (Any other actions discussed in the submittal represent intended or planned actions. They are described to the NRC for the NRCs information and are not regulatory commitments.)

COMMITMENT TYPE COMMITTED DATE ONE-TIME COMMITMENT Programmatic OR OUTAGE ACTION (Yes/No)

(Yes/No)

As part of the performance monitoring plan, The required Yes No CEG will examine one Examination examination will be Category B-B, Item B2.11 shell-to-head completed by the weld and one Category B-D, B3.110 nozzle- end of 2034 to to-vessel weld from the Byron Station, Unit 2 ensure that no more to the maximum extent possible. The than 20 years components available for examination are elapses between the provided in the Table below. performance of an ASME XI examination for the Category B-B and B-D components at Byron Station, Unit 2.

ASME ASME Unit Component ID Component Description Category Item 2 B-B B2.11 2RY-01-S/PC-01 Shell - Bottom Head 2 B-B B2.11 2RY-01-S/PC-05 Shell - Upper Head 2 B-B B2.12 2RY-01-S/PL-01 Lower Longitudinal Weld 2 B-B B2.12 2RY-01-S/PL-04 Upper Longitudinal Weld 2 B-D B3.110 2RY-01-S/PN-01 Surge Nozzle 2 B-D B3.110 2RY-01-S/PN-02 Spray Nozzle 2 B-D B3.110 2RY-01-S/PN-03 Relief Nozzle 2 B-D B3.110 2RY-01-S/PN-04 Safety Nozzle 2 B-D B3.110 2RY-01-S/PN-05 Safety Nozzle 2 B-D B3.110 2RY-01-S/PN-06 Safety Nozzle