05000260/LER-2025-003-01, Primary Containment Isolation and Manual Reactor Trip Due to Dual Recirculation Pump Trips
| ML25300A115 | |
| Person / Time | |
|---|---|
| Site: | Browns Ferry  (DPR-052) |
| Issue date: | 10/27/2025 |
| From: | Komm D Tennessee Valley Authority |
| To: | Office of Nuclear Reactor Regulation, Document Control Desk |
| References | |
| LER 2025-003-01 | |
| Download: ML25300A115 (1) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(iv)(A), System Actuation |
| 2602025003R01 - NRC Website | |
text
Post Office Box 2000, Decatur, Alabama 35609-2000 October 27, 2025 10 CFR 50.73 ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, D.C. 20555-0001 Browns Ferry Nuclear Plant, Unit 2 Renewed Facility Operating License No. DPR-52 NRC Docket No. 50-260
Subject:
Licensee Event Report 50-260/2025-003-01
Reference:
Letter from TVA to NRC, License Event Report 50-260/2025-003-00, dated July 29, 2025 (ML25210A472)
The enclosed Licensee Event Report provides details of a Primary Containment Isolation and Manual Reactor Trip Due to Dual Recirculation Pump Trips. The Tennessee Valley Authority is submitting this report in accordance with Title 10 of the Code of Federal Regulations (10 CFR) 50.73(a)(2)(iv)(A), as a manual actuation of the Reactor Protection System and the Primary Containment Isolation System.
There are no new regulatory commitments contained in this letter. Should you have any questions concerning this submittal, please contact David J. Renn, Site Regulatory Compliance Manager, at (256) 729-2636.
Respectfully, Daniel A. Komm Site Vice President Enclosure: Licensee Event Report 50-260/2025-003 Primary Containment Isolation and Manual Reactor Trip Due to Dual Recirculation Pump Trips cc (w/ Enclosure):
NRC Regional Administrator - Region II NRC Senior Resident Inspector - Browns Ferry Nuclear Plant NRC Project Manager - Browns Ferry Nuclear Plant
Browns Ferry Nuclear Plant Unit 2 Licensee Event Report 50-260/2025-003-01 Primary Containment Isolation and Manual Reactor Trip Due to Dual Recirculation Pump Trips See Enclosed
Abstract
On May 30, 2025, Recirculation (Recirc) Pump Variable Frequency Drive (VFD) 2A and 2B 120VAC Auxiliary Power Distribution had a contactor fail to transmit power from the normal source and fail to transfer to the alternate source resulting in the loss of Normal and Alternate power to the VFD Cooling Fans. Subsequently, excessive temperatures in VFD cabinets caused multiple VFD cells to auto bypass which caused automatic trips of both Recirc Pumps and, ultimately, an insertion of a manual reactor scram in accordance with 2-AOI-68-1, Recirc Pump Trip/Core Flow Decrease.
The power loss was caused by an incorrect risk evaluation/preventative maintenance strategy for a contactor. Corrective actions included contactor replacement, which allowed the reactor to restart and sync to the electrical grid on June 6, 2025. Preventative actions include similar contactor replacements, evaluations, and maintenance strategies as well as the future addition of power supply redundancies.
The Tennessee Valley Authority is submitting this report in accordance with Title 10 of the Code of Federal Regulations (10 CFR) 50.73(a)(2)(iv)(A), as any event or condition that resulted in manual or automatic actuation of the Reactor Protection System and the Primary Containment Isolation System.
VII. Previous Similar Events at the Same Site
A search of LERs from BFN, Units 1, 2, and 3 over the last five years identified no similar events.
VIII. Additional Information
There is no additional information.
IX.
Commitments
There are no new commitments.
Energy Industry Identification System (EIIS) codes are identified in the text as [XX].