PNO-III-06-012, Kewaunee, Manual Reactor Shutdown Following Feedwater Pump Trip
| ML061180349 | |
| Person / Time | |
|---|---|
| Site: | Kewaunee  |
| Issue date: | 04/28/2006 |
| From: | Louden P Division of Nuclear Materials Safety III |
| To: | |
| References | |
| PNO-III-06-012 | |
| Download: ML061180349 (1) | |
April 28, 2006 PRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE -- PNO-III-06-0012 This preliminary notification constitutes EARLY notice of events of POSSIBLE safety or public interest significance. The information is as initially received without verification or evaluation, and is basically all that is known by the Region III staff on this date.
Facility Kewaunee Dominion Energy Kewaunee, Inc.
Docket: 50-305 License: DPR-43 Licensee Emergency Classification Notification of Unusual Event x Alert Site Area Emergency General Emergency Not Applicable
SUBJECT:
MANUAL REACTOR SHUTDOWN FOLLOWING FEEDWATER PUMP TRIP DESCRIPTION:
On April 26, 2006, the A feedwater pump tripped while plant operators were reducing power in preparation for a maintenance outage to repair a pipe leak in the service water system. Since the B feedwater pump was already shut down, the tripping of the operating pump should have caused a turbine trip followed by a reactor trip.
When the turbine did not trip, operators took manual action to shut down the reactor, which tripped the turbine. All reactor safety systems functioned as designed during the shutdown. A loss of condenser vacuum removed the normal method for cooling down the reactor, and operators used the power-operated relief valves to release steam to the atmosphere. The auxiliary feedwater system started and provided flow to the steam generators.
The licensee declared an Alert under its emergency plan at 8:49 p.m. CDT because the turbine did not trip automatically after the feedwater pump shut down. The Alert was terminated at 12:24 a.m. on April 27, 2006.
The senior resident inspector responded to the site, and the Headquarters Operation Center and Region III Incident Response Center were staffed to monitor the event.
Region III dispatched a Special Inspection Team to review the circumstances surrounding the event.
The licensee and Region III issued news releases, and Region III responded to news media inquiries. The State of Wisconsin has been informed. The information in this preliminary notification has been reviewed with licensee management.
The licensee notified the NRC Operations Center of this event at 9:39 p.m. CDT on April 26, 2006. This information is current as of 10:00 a.m. on April 28, 2006.
CONTACTS: Patrick Louden 630/829-9627