Event Notification Report for November 27, 2008
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
11/26/2008 - 11/27/2008
EVENT NUMBERS
44791
Power Reactor
Event Number: 44791
Facility: GRAND GULF
Region: 4 State: MS
Unit: [1] [] []
RX Type: [1] GE-6
NRC Notified By: MICHAEL J. LARSON
HQ OPS Officer: DONALD NORWOOD
Region: 4 State: MS
Unit: [1] [] []
RX Type: [1] GE-6
NRC Notified By: MICHAEL J. LARSON
HQ OPS Officer: DONALD NORWOOD
Notification Date: 01/20/2009
Notification Time: 15:01 [ET]
Event Date: 11/27/2008
Event Time: 10:16 [CST]
Last Update Date: 01/20/2009
Notification Time: 15:01 [ET]
Event Date: 11/27/2008
Event Time: 10:16 [CST]
Last Update Date: 01/20/2009
Emergency Class: NON EMERGENCY
10 CFR Section:
50.73(a)(1) - INVALID SPECIF SYSTEM ACTUATION
10 CFR Section:
50.73(a)(1) - INVALID SPECIF SYSTEM ACTUATION
Person (Organization):
THOMAS FARNHOLTZ (R4)
THOMAS FARNHOLTZ (R4)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 1 | N | Y | 100 | Power Operation | 100 | Power Operation |
INVALID ACTUATION OF CONTAINMENT ISOLATION FUNCTION
"On November 27, 2008 at 10:16 Central Standard Time, while operating at 100 percent power, Grand Gulf Nuclear Station experienced an invalid actuation resulting in isolation of containment isolation valves for two different systems. A failed temperature monitoring relay resulted in the invalid actuation of the isolation logic for the Reactor Core Isolation Cooling (RCIC) and Residual Heat Removal (RHR) 'A' systems. The RCIC system was declared inoperable. RHR 'A' system operability was not affected. Appropriate procedures and Technical Specification Limiting Condition for Operations (LCOs) were entered and implemented. There were no abnormal temperatures found during the initial investigations by plant operators for the affected rooms and systems, therefore the actuation was considered invalid. The actuation was considered a complete actuation of Division 1, Group 3 and Group 4 isolation valves. Corrective actions were taken to replace the failed temperature relay. This report is made under 10CFR50.73(a)(2)(iv)(A)."
The licensee notified the NRC Resident Inspector.
"On November 27, 2008 at 10:16 Central Standard Time, while operating at 100 percent power, Grand Gulf Nuclear Station experienced an invalid actuation resulting in isolation of containment isolation valves for two different systems. A failed temperature monitoring relay resulted in the invalid actuation of the isolation logic for the Reactor Core Isolation Cooling (RCIC) and Residual Heat Removal (RHR) 'A' systems. The RCIC system was declared inoperable. RHR 'A' system operability was not affected. Appropriate procedures and Technical Specification Limiting Condition for Operations (LCOs) were entered and implemented. There were no abnormal temperatures found during the initial investigations by plant operators for the affected rooms and systems, therefore the actuation was considered invalid. The actuation was considered a complete actuation of Division 1, Group 3 and Group 4 isolation valves. Corrective actions were taken to replace the failed temperature relay. This report is made under 10CFR50.73(a)(2)(iv)(A)."
The licensee notified the NRC Resident Inspector.