Event Notification Report for August 09, 2008
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
08/08/2008 - 08/09/2008
EVENT NUMBERS
44402
Power Reactor
Event Number: 44402
Facility: COOPER
Region: 4 State: NE
Unit: [1] [] []
RX Type: [1] GE-4
NRC Notified By: ROY GILES
HQ OPS Officer: BILL HUFFMAN
Region: 4 State: NE
Unit: [1] [] []
RX Type: [1] GE-4
NRC Notified By: ROY GILES
HQ OPS Officer: BILL HUFFMAN
Notification Date: 08/09/2008
Notification Time: 05:24 [ET]
Event Date: 08/09/2008
Event Time: 02:04 [CDT]
Last Update Date: 08/09/2008
Notification Time: 05:24 [ET]
Event Date: 08/09/2008
Event Time: 02:04 [CDT]
Last Update Date: 08/09/2008
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(2)(iv)(B) - RPS ACTUATION - CRITICAL 50.72(b)(3)(iv)(A) - VALID SPECIF SYS ACTUATION
10 CFR Section:
50.72(b)(2)(iv)(B) - RPS ACTUATION - CRITICAL 50.72(b)(3)(iv)(A) - VALID SPECIF SYS ACTUATION
Person (Organization):
MICHAEL SHANNON (R4)
MICHAEL SHANNON (R4)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 1 | M/R | Y | 69 | Power Operation | 0 | Hot Shutdown |
MANUAL REACTOR SCRAM DUE TO FAILURE OF REHEAT STOP VALVE TO OPEN DURING TURBINE VALVE TESTING
"While performing main turbine reheat stop valve surveillance testing, Reheat Stop Valve 1RV 1A failed to reopen simultaneously with a Moisture Separator C high level alarm. Plant alarm response procedures require a reactor scram in this situation. Operating crew inserted a manual scram at 0204 CDT. Immediately after the scram, RPV level responded as expected and dropped below the Group 2 containment isolation setpoint. All rods inserted fully. RPV level is being controlled with RFP A and the startup valves. RPV pressure is being controlled on the bypass valves. The Group 2 isolation was complete with no anomalies.
"This report is being submitted pursuant to 50.72(b)(2) for RPS actuation (4 hour report) and 50.72(b)(3) for a valid Group 2 isolation (8 hour report)."
The scram was characterized as uncomplicated. The lowest reactor vessel water level reached was - 20 inches. No safeties lifted during the transient and all systems functioned as required. The cause of the reheat stop valve failure to reopen is under investigation.
The NRC Resident Inspector has been notified.
"While performing main turbine reheat stop valve surveillance testing, Reheat Stop Valve 1RV 1A failed to reopen simultaneously with a Moisture Separator C high level alarm. Plant alarm response procedures require a reactor scram in this situation. Operating crew inserted a manual scram at 0204 CDT. Immediately after the scram, RPV level responded as expected and dropped below the Group 2 containment isolation setpoint. All rods inserted fully. RPV level is being controlled with RFP A and the startup valves. RPV pressure is being controlled on the bypass valves. The Group 2 isolation was complete with no anomalies.
"This report is being submitted pursuant to 50.72(b)(2) for RPS actuation (4 hour report) and 50.72(b)(3) for a valid Group 2 isolation (8 hour report)."
The scram was characterized as uncomplicated. The lowest reactor vessel water level reached was - 20 inches. No safeties lifted during the transient and all systems functioned as required. The cause of the reheat stop valve failure to reopen is under investigation.
The NRC Resident Inspector has been notified.