PNO-III-11-004, A, LaSalle, Unit 1, Restart Following Automatic Reactor Scram and Shutdown Greater than 72 Hours Due to a Main Power Transformer Trip
| ML110450341 | |
| Person / Time | |
|---|---|
| Site: | LaSalle  |
| Issue date: | 02/14/2011 |
| From: | Ramirez F, Nirodh Shah NRC/RGN-III |
| To: | |
| References | |
| PNO-III-11-004A | |
| Download: ML110450341 (1) | |
PRELIMINARY NOTIFICATION - REGION III February 14, 2011 PRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE
This preliminary notification constitutes EARLY notice of events of POSSIBLE safety or public interest significance. Some of the information may not yet be fully verified or evaluated by the Region III staff.
Facility LaSalle Station, Unit 1 Exelon Generation Co. Marseilles, IL Docket: 50-373 License: NPF-11 Licensee Emergency Classification Notification of Unusual Event Alert Site Area Emergency General Emergency X Not Applicable
SUBJECT:
LASALLE UNIT 1 RESTART FOLLOWING AUTOMATIC REACTOR SCRAM AND SHUTDOWN GREATER THAN 72 HOURS DUE TO A MAIN POWER TRANSFORMER TRIP DESCRIPTION:
At 6:15 p.m. (CST) on February 12, 2011, LaSalle Unit 1 was returned to full power operation following a forced outage. The outage began on February 1, following an automatic scram due to a main power transformer trip. The circumstances of the trip were summarized in NRC Event Notice 46582.
During the restart of Unit 1 on February 9, a steam leak was identified from a valve associated with the reactor core isolation cooling system. Unit 1 was subsequently shutdown to repair the leak. The circumstances of the steam leak were described in NRC Event Notice 46605. The licensee repaired the leak on February 10, and subsequently restarted the unit.
The NRC resident inspectors were monitoring the troubleshooting, repair, and restart activities at the plant.
This preliminary notification is issued for information only. State and local officials have been informed. The site issued a press release on February 11, 2011, describing the restart of LaSalle Unit 1.
The information presented herein has been discussed with the licensee, and is current as of 10:00 a.m. (CST), February 14, 2011.
ADAMS Accession Number ML110450341.
CONTACTS: Frances Ramirez Nirodh Shah 815/357-8611 630/829-9821 Frances.Ramirez@nrc.gov Nirodh.Shah@nrc.gov