ML25069A472
| ML25069A472 | |
| Person / Time | |
|---|---|
| Site: | Wolf Creek, Peach Bottom  |
| Issue date: | 03/10/2025 |
| From: | Hamman D Wolf Creek |
| To: | Office of Nuclear Material Safety and Safeguards, Office of Nuclear Reactor Regulation, Document Control Desk |
| References | |
| 000878 | |
| Download: ML25069A472 (1) | |
Text
P.O. Box 411 l Burlington, KS 66839 l 620-364-8831 Dustin T. Hamman Director Nuclear and Regulatory Affairs March 10, 2025 000878 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001
Subject:
Docket No. 50-482 and 72-79: Wolf Creek Generating Station 50.59 and 72.48 Evaluation Report Commissioners and Staff:
In accordance with 10 CFR 50.59(d)(2) and 10 CFR 72.48(d)(2), this letter transmits a report that summarizes the 10 CFR 50.59 and 10 CFR 72.48 evaluations for changes, tests, and experiments implemented within their respective reporting periods for activities at Wolf Creek Generating Station.
This report covers all 10 CFR 50.59 evaluations that were approved by the Plant Safety Review Committee and implemented between January 1, 2023, to December 31, 2024.
This report is also intended to cover all 10 CFR 72.48 evaluations implemented for the period of January 1, 2024, to December 31, 2024. However, there were no changes, tests or experiments that required a 10 CFR 72.48 evaluation during this period of time.
This letter contains no commitments. If you have any questions concerning this matter, please contact me at (620) 364-4204.
Sincerely, Dustin T. Hamman DTH/jkt
000878 Page 2 of 2
Attachment:
Wolf Creek Generating Station Biennial 50.59 and 72.48 Evaluation Report cc:
A. N. Agrawal (NRC), w/a S. S. Lee (NRC), w/a J. D. Monninger (NRC), w/a Senior Resident Inspector (NRC), w/a WC Licensing Correspondence - RA 25-000878, w/a
Attachment to 000878 Page 1 of 3 WOLF CREEK NUCLEAR OPERATING CORPORATION Wolf Creek Generating Station Docket No: 50.482 and 72-79 Facility Operating License No. NPF-42 BIENNIAL 50.59 AND 72.48 EVALUATION REPORT Report No.: 29 10 CFR 50.59 Reporting Period: January 1, 2023, through December 31, 2024 10 CFR 72.48 Reporting Period: January 1, 2024, through December 31, 2024
Attachment to 000878 Page 2 of 3
SUMMARY
In accordance with 10 CFR 50.59(d)(2) and 10 CFR 72.48(d)(2), a summary report has been prepared which provides summaries of the 10 CFR 50.59 and 10 CFR 72.48 evaluations of changes, tests, and experiments implemented for activities at Wolf Creek Generating Station (WCGS). All 10 CFR 50.59 and 10 CFR 72.48 evaluations have been approved by the Plant Safety Review Committee (PSRC) prior to implementation.
This report covers all 10 CFR 50.59 evaluations for changes, tests, and experiments that were implemented from January 1, 2023, through December 31, 2024. Based on the 10 CFR 50.59 evaluations performed, none of the activities described in this report required a license amendment.
Additionally, this report is intended to cover all 10 CFR 72.48 evaluations for changes, tests, and experiments that were implemented from January 1, 2024, through December 31, 2024, for the independent spent fuel storage installation (ISFSI) at WCGS. However, during this period there were no changes, tests, or experiments implemented that required a 10 CFR 72.48 evaluation.
Attachment to 000878 Page 3 of 3 Evaluation Number: 59 2023-0001
Title:
System Descriptions M-10BN and M-10EN Update Note: WCGS System Designators BN - Borated Refueling Water Storage System EN - Containment Spray System Activity
Description:
Condition Reports (CRs) 10014808, 10015262, 10017090, and 10017620 identified issues with calculations BN-20, BN-M-013, FL-18, and EN-33. To resolve the issues, revisions to calculations BN-20, BN-M-013, and FL-18, a Calculation Change Notice (CCN) to calculation EN-33, and revisions to system descriptions M-10BN and M-10EN and EQSD-1 are required. The Updated Safety Analysis Report (USAR) will also need to be updated to reflect the changes.
The 50.59 screening identified three adverse changes to USAR described design functions. The adverse changes are as follows:
The minimum volume of water delivered to containment from the Refueling Water Storage Tank (RWST) decreased for all values (LOCA and MSLB, ECCS switchover, containment spray switchover, and long-term recirculation). This is based on calculation BN-20, where the starting point for the injection volume was revised from the LOLO setpoint to the Technical Specification minimum volume for the RWST. This results in a decrease to the total minimum water volume delivered to containment. This incorporates an additional small change due to the reduction in the minimum volume of water delivered by the accumulator tanks due to including instrument uncertainty to the tank level measurement in calculation FL-18. It also includes a reduction in the shortest injection mode operating time before Emergency Core Cooling System (ECCS) swapover from 13.0 to 12.18 minutes.
The minimum operator time available for accomplishing the alignment of ECCS pumps suctions to containment recirculation sumps with two train operation and postulated single active component failure decreased from 8.25 minutes to 8.17 minutes. This is a result of a slight change to calculation BN-M-013, where a valve stroke time was adjusted (i.e.,
increased) by 8 seconds.
The available net positive suction head (NPSH) for the containment spray pumps when operating in recirculation mode (i.e., taking suction from the containment recirculation sumps) decreased to 19.62 ft. This is a result of calculation change notice EN-33-002-CN002, which revised the NPSH analysis to be aligned with the licensing basis.
50.59 Evaluation:
The activity does not alter anything physically in the plant. There is margin available in the minimum time for the RWST to drain down to recirculation mode and in the available net positive suction head for the containment spray pumps taking suction from the containment recirculation sumps. Operators are able to successfully complete the switchover of the ECCS pumps with the allowed time. The design functions of the ECCS, containment spray, and RWST will continue to be met as required.