ML25083A059
| ML25083A059 | |
| Person / Time | |
|---|---|
| Site: | Comanche Peak  |
| Issue date: | 04/03/2025 |
| From: | Dennis Galvin NRC/NRR/DORL/LPL4 |
| To: | Vistra Operations Company |
| Lee, Samson | |
| References | |
| EPID L-2024-LLR-0079 RV-1A | |
| Download: ML25083A059 (1) | |
Text
April 3, 2025 LICENSEE:
Vistra Operations Company, LLC FACILITY:
Comanche Peak Nuclear Power Plant, Unit No. 1
SUBJECT:
SUMMARY
OF FEBRUARY 25, 2025, PUBLIC OBSERVATION MEETING WITH VISTRA OPERATIONS COMPANY LLC ON ALTERNATIVE REQUEST RV-1A FOR EXTENSION OF THERMAL RELIEF VALVE TEST INTERVAL (EPID L-2024-LLR-0079)
On February 25, 2025, the U.S. Nuclear Regulatory Commission (NRC) staff held a public observation virtual meeting with Vistra Operations Company LLC (the licensee). The purpose of the meeting was to discuss the licensees Alternative Request RV-1A, which requests authorization to perform alternate inservice testing activities for certain valves at Comanche Peak Nuclear Power Plant, Unit No. 1. Specifically, the licensee proposed to extend the requirement to test or replace two thermal relief valves in the station service water (SSW) system, which provide overpressure protection for the SSW side of the component cooling water (CCW) heat exchangers. The licensees submittal, dated December 11, 2024, is available in the NRCs Agencywide Documents Access and Management System (ADAMS) at Accession No. ML24346A143. The meeting notice and agenda, dated February 11, 2025, are available in ADAMS at Accession No. ML25055A257. Enclosed is a list of attendees at the meeting. The NRC staff identified five discussion topics for the meeting (ML25029A203). The licensee provided presentation slides on the discussion topics (ML25055A209).
For Topic 1, the licensee stated that Shift Manager Caution Tags will be placed on the CCW heat exchanger isolation valves and vent valves requiring the CCW heat exchangers to be vented upon isolation and to remain vented until the CCW heat exchanger is no longer isolated from the safe shutdown impoundment. The licensee discussed the current process and standard training to ensure plant personnel are aware of the Shift Manager Caution Tags on the isolation and vent valves. The licensee confirmed if plant personnel needed to operate the valve(s), they would be required to read and understand the tag prior to operating each valve.
For Topic 2, the licensee explained that once the replacement thermal relief valves are obtained, then applicable work orders could be added to the forced outage list for management evaluation. The licensee also discussed that the extension request is considered to be of low risk, while an at-power or forced outage valve replacement activity would introduce a safety risk due to the CCW heat exchanger being a means of connection between the reactor vessel and the ultimate heat sink.
For Topic 3, the licensee identified that the extension requested per the December 11, 2024, submittal, would provide an additional 1.5 years; however, the licensee has no record of testing or maintenance, so they estimate that it has been approximately 50 years since the thermal relief valves were last tested. The licensee has a high level of confidence that the thermal relief valves will be able to perform their safety function (remaining closed to maintain the system pressure boundary) based on site operating experience.
In Topic 4, the licensee confirmed that 52 of the 54 thermal relief valves identified in the request submittal dated April 13, 2023, for the previously authorized Alternative Request RV-1 (ML23108A246) have been restored to compliance with the applicable American Society of Mechanical Engineers Code for Operation and Maintenance of Nuclear Power Plants (ASME OM Code). The licensee also clarified that there was a counting error when referring back to Alternative Request RV-1, and the correct count is 17 out of the 19 valves, not 18 of the 20 valves as discussed in the December 11, 2024, submittal.
In Topic 5, the licensee provided a summary of past issues with the 54 thermal relief valves, which included 23 valves which were out of tolerance during testing. The licensee then discussed the impact of a stuck open relief valve, which would have no immediate impact on system operability and explained that plant personnel would troubleshoot to address the issue.
The NRC staff did not make any regulatory decisions at the meeting. Members of the public were not in attendance. Public Meeting Feedback forms were not received.
Please direct any inquiries to Hannah McLatchie, Project Manager, at 301-415-8507 or Hannah.McLatchie@nrc.gov.
/RA/
Dennis Galvin, Project Manager Plant Licensing Branch 4 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-445
Enclosure:
List of Attendees cc: Listserv
Enclosure LIST OF ATTENDEES FEBRUARY 25, 2025, MEETING WITH VISTRA OPERATIONS COMPANY LLC TO DISCUSS ALTERNATIVE REQUEST RV-1A FOR EXTENSION OF THERMAL RELIEF VALVE TEST INTERVAL COMANCHE PEAK NUCLEAR POWER PLANT, UNIT NO. 1 U.S. Nuclear Regulatory Commission Vistra Operations LLC.
Dennis Galvin Coleton Teplicek Gurjendra Bedi Jack Hicks Hannah McLatchie James Barnette Henry Strittmatter Neil Jones John Ellegood Phil Lashley Thomas Scarbrough Tony Nakanishi
Meeting Notice ML25055A257 Meeting Discussion Topics ML25029A203 Meeting Slides ML25055A209 Meeting Summary ML25083A059
- concurrence via email OFFICE NRR/DORL/LPL4/PM NRR/DORL/LPL4/PM* NRR/DORL/LPL4/LA* NRR/DEX/EMIB/BC*
NAME HMcLatchie DGalvin PBlechman SBailey DATE 3/14/2025 3/21/2025 3/26/2025 4/2/2025 OFFICE NRR/DORL/LPL4/BC* NRR/DORL/LPL4/PM*
NAME TNakanishi DGalvin (HMcLatchie for)
DATE 4/3/2025 4/3/2025