PNO-II-07-004, NRC Resident Inspector - Automatic Reactor Trip/ Plant Shutdown Greater than 72 Hours
| ML071150433 | |
| Person / Time | |
|---|---|
| Site: | Vogtle  |
| Issue date: | 04/25/2007 |
| From: | Scott Shaeffer NRC/RGN-II |
| To: | |
| S. M. Shaeffer,404-562-4521 | |
| References | |
| PNO-II-07-004 | |
| Download: ML071150433 (1) | |
April 25, 2007 PRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE PNO-II-07-004 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 Region II staff (Atlanta, Georgia) on this date.
Facility Licensee Emergency Classification Vogtle Nuclear Plant Notification of Unusual Event Unit 2 Alert Waynesboro, GA Site Area Emergency Dockets/License: 50-0425 General Emergency X Not Applicable
Subject:
AUTOMATIC REACTOR TRIP / PLANT SHUTDOWN GREATER THAN 72 HOURS On April 23, 2007 at approximately 10:25 a.m., Vogtle Unit 2 tripped from 53% power due to a turbine trip /
reactor trip caused by Reactor Protection System (RPS) actuation during power ascension following completion of a refueling outage. Initial investigation indicates that a generator neutral ground relay actuated causing an automatic main generator trip. No significant visual damage is apparent on any plant equipment.
All safety systems responded as expected. All control rods fully inserted upon (RPS) actuation, the steam generator atmospheric relief valves lifted momentarily and reseated as expected, and no safety valves lifted.
After the trip, steam generator level was maintained with the auxiliary feed pumps and steam was being dumped to the condenser. The plant was placed in the normal shutdown electrical lineup. The unit remains in Mode 3 at normal system operating temperature and pressure. The plant shutdown is expected to last greater than 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.
The NRC Resident Inspector was onsite and reported to the control room to monitor plant and personnel response to the trip.
Unit 1 was not affected by this issue and is currently operating at 100% power.
The facts contained within this PN were verified with the licensee. This information is current as of 11:00 a.m.
EDT on April 25, 2007.
The state of Georgia will be informed.
CONTACT: Scott M. Shaeffer 404-562-4521