PNO-III-06-022, Kewaunee Reactor Shutdown and Startup
| ML063180397 | |
| Person / Time | |
|---|---|
| Site: | Kewaunee  |
| Issue date: | 11/14/2006 |
| From: | Michael Kunowski, Louden P Division of Nuclear Materials Safety III |
| To: | |
| References | |
| PNO-III-06-022 | |
| Download: ML063180397 (2) | |
November 14, 2006 PRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE -- PNO-III-06-022 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 Licensee Emergency Classification Kewaunee Notification of Unusual Event Dominion Energy Alert Kewaunee, WI Site Area Emergency Docket: 50-305 General Emergency License: DPR-43 x Not Applicable
SUBJECT:
KEWAUNEE REACTOR SHUTDOWN AND STARTUP DESCRIPTION:
On Friday, November 10, 2006, the Kewaunee Power Station was at about 10 percent power and shutting down to evaluate a bearing associated with the main turbine when an automatic reactor trip occurred. Elevated bearing temperatures were observed over the preceding day, indicating the need for evaluation. At 2:20 p.m., the reactor shut down automatically when one of four power range nuclear instruments failed to operate properly with another of the four instruments already being out-of-service from the previous day (Event Notification 42983).
After the reactor trip, one of the two main feedwater regulating valves failed to fully close.
Reactor operators took appropriate compensatory actions to address the problem and safely shut down the reactor. The licensee inspected the main turbine bearing and cleared an obstruction in a cooling line to the bearing, repaired the two nuclear instruments, and investigated the cause of the feedwater valve not fully closing.
The investigation identified that a metal tube plug had dislodged from a feedwater heater upstream of the valve and become lodged in the valve. The licensee verified that the valve had not been damaged by the plug, verified no other plugs were missing from the heater, and installed a replacement plug in the heater.
On Tuesday, November 14, 2006, the licensee restarted the reactor and will be resuming full power operations.
The NRC resident inspectors are observing the licensees activities.
The State of Wisconsin will be notified.
This information is current as of 7:00 a.m. on November 14, 2006.
The information in this preliminary notification has been reviewed with license management.
CONTACTS:
Patrick Louden Michael Kunowski 630/829-9627 630/829-9618