05000364/LER-2025-001, Joseph Farley, Unit 2, Containment Isolation Valve Inoperable for Longer than Allowed by Technical Specifications
| ML25036A236 | |
| Person / Time | |
|---|---|
| Site: | Farley  |
| Issue date: | 02/05/2025 |
| From: | Dean E Southern Nuclear Operating Co |
| To: | Office of Nuclear Reactor Regulation, Document Control Desk |
| References | |
| NL-25-0028 LER 2025-001-00 | |
| Download: ML25036A236 (1) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications |
| 3642025001R00 - NRC Website | |
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3/4. Southern Nuclear February 5, 2025 Docket No.:
50-364 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D. C. 20555-0001 Edwin Dean Ill Vice President - Farley Joseph M. Farley Nuclear Plant-Unit 2 Licensee Event Report 2025-001-00 Joseph M. Farley Nuclear Plant 7388 North State Hwy 95 Columbia, Alabama 363 19 334.661.2100 tel 334.661.2512 fax EDDEANI If.<! southernco.com NL-25-0028 Containment Isolation Valve Inoperable for Longer than Allowed by Technical Specifications Ladies and Gentlemen:
In accordance with the requirements of 10 CFR 50.73(a)(2)(i)(B), Southern Nuclear Company is submitting the enclosed Licensee Event Report for Unit 2. The enclosed LER describes a condition which was prohibited by Technical Specifications.
This letter contains no NRC commitments. If you have any questions regarding this submittal, please contact Mandy Ludlam, Licensing Engineer, at (334) 661-2886.
Respectfully submitted, Edwin Dean Ill Vice President-Farley ED/mml/cbg Enclosure: Unit 2 Licensee Event Report 2025-001-00 Cc:
Regional Administrator, Region II NRR Project Manager-Farley Nuclear Plant Senior Resident Inspector - Farley Nuclear Plant RTYPE: CFA04.054
Joseph M. Farley Nuclear Plant - Unit 2 Licensee Event Report 2025-001-00 Containment Isolation Valve Inoperable for Longer than Allowed by Technical Specifications Enclosure Unit 2 Licensee Event Report 2025-001-00
Abstract
At 0423 CDT on October 17, 2023, with Joseph M. Farley Nuclear Plant (FNP) Unit 2 at 0% power level and in Mode 6 (Refueling), it was determined through surveillance testing that containment isolation valve Q2P17HV3067 (HV3067),
Component Cooling Water (CCW) from Excess Letdown/Reactor Coolant Drain Tank Heat Exchangers, did not close on a simulated Safety Injection (SI) signal and was subsequently declared inoperable. Investigation determined that dirty contacts in the handswitch (Q2P17HS3067) caused the switch to supply a continuous "open" signal resulting in HV3067 not changing position. Corrective action included cleaning the handswitch contacts, and the handswitch is scheduled for replacement during the next refueling outage. The surveillance was completed satisfactorily on October 27, 2023, and HV3067 returned to operable status. Since HV3067 last demonstrated that it could perform its safety function during surveillance testing on April 21, 2022, this condition is being reported in accordance with 10 CFR 50.73(a)(2)(i)(B) for the containment isolation valve being inoperable for longer than allowed by Technical Specification 3.6.3, "Containment Isolation Valves." FNP Unit 1 was not affected during this event.
EVENT DESCRIPTION
- 2. DOCKET NUMBER
- 3. LER NUMBER I
364 D
NUMBER NO.
I YEAR SEQUENTIAL REV
~-I 001 1-G At 0423 CDT on October 17, 2023, with Joseph M. Farley Nuclear Plant (FNP) Unit 2 at 0% power level and in Mode 6 (Refueling), with the Reactor Coolant System [EIIS: AB] at atmospheric pressure and 98 degrees Fahrenheit, it was determined through surveillance testing that containment isolation valve [EIIS: ISV] Q2P17HV3067 (HV3067), Component Cooling Water (CCW) [EIIS: CC) from Excess Letdown/Reactor Coolant Drain Tank (RCDT) Heat Exchangers [EIIS: HX],
did not close on a simulated Safety Injection (SI) signal and was subsequently declared inoperable. The surveillance was completed satisfactorily at 0542 CDT on October 27, 2023, and HV3067 returned to operable status.
HV3067 last demonstrated that it could perform its safety function during surveillance testing on April 21, 2022. No additional strokes of HV3067 were identified between surveillance testing on April 21, 2022, and the failure to close on October 17, 2023.
EVENT ANALYSIS
Investigation determined that dirty contacts in handswitch [EIIS: HS] Q2P17HS3067 (Manufacturer: GEMCO, Model:
404S32221-Y-A3A11A3) caused the switch to supply a continuous "open" signal resulting in HV3067 not changing position.
Corrective action included cleaning the handswitch contacts, and handswitch replacement is scheduled for the next refueling outage.
REPORTABILITY AND SAFETY ASSESSMENT
There were no safety consequences since Q2P17HV3443 (HV3443), CCW from Excess Letdown/RCDT Heat Exchanger, was available to perform the same function as HV3067. HV3443 was able to close on an SI signal. Containment isolation from the excess letdown heat exchanger can be performed through either HV3443 (inside containment) or HV3067 (outside containment) due to their redundancy on the same line and both valves closing on a containment isolation actuation signal.
The event was within the analysis of UFSAR Chapter 15 and is reportable per 10 CFR 50. 73(a)(2)(i)(B) for the containment isolation valve being inoperable for longer than allowed by Technical Specification 3.6.3, "Containment Isolation Valves."
FNP Unit 1 was not affected during this event.
CORRECTIVE ACTIONS PLANNED OR COMPLETED
(1) Cleaned handswitch contacts (2) Replace handswitch during next refueling outage
PREVIOUS SIMILAR EVENTS
There were no events from the last ten years with the same or similar cause as this event. Page 2
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