05000334/LER-2024-004, Reactor Trip Due to Bypass Feedwater Regulating Valve Failure to Control
| ML24199A242 | |
| Person / Time | |
|---|---|
| Site: | Beaver Valley |
| Issue date: | 07/17/2024 |
| From: | Blair B Vistra Operations Company |
| To: | Office of Nuclear Reactor Regulation, Document Control Desk |
| References | |
| L-24-158 LER 2024-004-00 | |
| Download: ML24199A242 (1) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(iv)(B)(1) 10 CFR 50.73(a)(2)(iv)(B)(6) |
| 3342024004R00 - NRC Website | |
text
L-24-158 July 17, 2024 ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, DC 20555-0001
SUBJECT:
Beaver Valley Power Station, Unit Nos. 1 Docket No. 50-334, License No. DPR-66 LER 2024-004-00 Beaver Valley Powr Station Barry N. Blair Site Vice President P.O. Box4 Shippingport, PA 15077 10 CFR 50.73 Enclosed is Licensee Event Report (LER) 2024-004-00, "Reactor Trip Due to Bypass Feedwater Regulating Valve Failure to Control." This event is being reported in accordance with 10 CFR 50.73(a)(2)(iv)(B)(1) and 10 CFR 50.73(a)(2)(iv)(B)(6).
There are no regulatory commitments contained in this submittal. If there are any questions or if additional information is required, please contact Ms. Hope Gilliam, Manager, Regulatory Compliance, at 724-682-4224.
Beaver Valley Power Station Unit No. 1 L-24-158 Page 2 Enclosure: Beaver Valley Power Station, Unit No. 1 LER 2024-004-00 cc: NRC Region I Administrator NRC Senior Resident Inspector NRC Project Manager INPO Records Center (via INPO Industry Reporting and Information System)
BRP/DEP
Enclosure L-24-158 Beaver Valley Power Station, Unit No. 1 LER 2024-004-00
Abstract
On May 19, 2024, during startup from the twenty-ninth refueling outage (1R29) with Beaver Valley Power Station, Unit No. 1 (BVPS-1) at approximately 14 percent reactor power, operators initiated a manual reactor trip on low steam generator (SG) water level after multiple attempts to establish control of the A SG water level. The cause was excessive air leakage on the actuator for the A train bypass feedwater regulating valve. Corrective actions include repair of the leak prior to restart and a full actuator overhaul planned for prior to the next refueling outage.
This event is reportable as an event that resulted in a manual actuation of the reactor protection system per 10 CFR 50.73(a)(2)(iv)(B)(1) and an automatic actuation of the auxiliary feedwater system per 10 CFR 50.73(a)(2)(iv)(B)(6).
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M120 07 17Page of
- 3. LER NUMBER YEAR SEQUENTIAL NUMBER REV NO.
052 050
CORRECTIVE ACTIONS
The leak was repaired and the actuator was tuned on May 21, 2024.
The actuator will be fully overhauled prior to the next refueling outage.
Assign a designated challenger for any systems described in the Unit 1 SCRAM reduction plan to challenge any decision to not repair a known condition.
PREVIOUS SIMILIAR EVENTS (Past 5 years)
On September 30, 2023 with BVPS-1 at 100 percent power, the A main feedwater regulating valve was not maintaining steam generator level in automatic and was difficult to control in manual. This resulted in reducing reactor power to 28% to repair the A main feedwater regulating valve. The direct cause was a sticking pilot valve in the actuators pneumatic positioner caused by foreign material. The positioner was replaced, the valve returned to service, and the reactor returned to 100 percent power.
On April 16, 2020 with BVPS-1 at 100% power, the C main feedwater regulating valve auto/manual controller failed to transfer back to auto. This resulted in reducing reactor power to 28% to repair the C main feedwater regulating valve.
The direct cause was a failed flow controller. The flow controller was replaced, the valve returned to service, and the reactor returned to 100 percent power.
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Beaver Valley Power Station, Unit 1 334 2024 004 00