Event Notification Report for December 23, 2011
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
12/22/2011 - 12/23/2011
Power Reactor
Event Number: 47549
Facility: RIVER BEND
Region: 4 State: LA
Unit: [1] [] []
RX Type: [1] GE-6
NRC Notified By: DOUG HALL
HQ OPS Officer: VINCE KLCO
Region: 4 State: LA
Unit: [1] [] []
RX Type: [1] GE-6
NRC Notified By: DOUG HALL
HQ OPS Officer: VINCE KLCO
Notification Date: 12/23/2011
Notification Time: 10:10 [ET]
Event Date: 12/23/2011
Event Time: 06:10 [CST]
Last Update Date: 12/23/2011
Notification Time: 10:10 [ET]
Event Date: 12/23/2011
Event Time: 06:10 [CST]
Last Update Date: 12/23/2011
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(2)(iv)(B) - RPS ACTUATION - CRITICAL
10 CFR Section:
50.72(b)(2)(iv)(B) - RPS ACTUATION - CRITICAL
Person (Organization):
BOB HAGAR (R4DO)
BOB HAGAR (R4DO)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 1 | A/R | Y | 100 | Power Operation | 0 | Hot Shutdown |
AUTOMATIC REACTOR SCRAM DUE TO A TURBINE TRIP
"At 0610 CST on 12/23/2011 with the reactor at 100% power, River Bend Station experienced an [automatic] reactor scram resulting from a RPS actuation. Following the scram, reactor water level briefly lowered below level 3, resulting in the automatic closure of containment isolation valves in the suppression pool cooling system. This isolation was confirmed to have occurred as designed. The reactor is stable with pressure and temperature being controlled by the feed water system and main steam bypass valves, respectively. The cause of the scram was due to a turbine trip. Initial indications are that the turbine tripped due to a loss speed sensor. All control rods inserted and Reactor Core Isolation Cooling was manually operated for approximately 1 minute and secured,
"The plant is conducting causal investigations to fully understand the cause of the turbine trip. As information becomes available River Bend Station will provide additional information.
"This event is being reported in accordance with 10CFR50.72(b)(iv)(B) as an automatic RPS actuation with the reactor critical."
The safety relief valves momentarily lifted immediately following the scram. The plant electrical distribution system is in a normal shutdown configuration. The scram was uncomplicated.
The licensee notified the NRC Resident Inspector.
"At 0610 CST on 12/23/2011 with the reactor at 100% power, River Bend Station experienced an [automatic] reactor scram resulting from a RPS actuation. Following the scram, reactor water level briefly lowered below level 3, resulting in the automatic closure of containment isolation valves in the suppression pool cooling system. This isolation was confirmed to have occurred as designed. The reactor is stable with pressure and temperature being controlled by the feed water system and main steam bypass valves, respectively. The cause of the scram was due to a turbine trip. Initial indications are that the turbine tripped due to a loss speed sensor. All control rods inserted and Reactor Core Isolation Cooling was manually operated for approximately 1 minute and secured,
"The plant is conducting causal investigations to fully understand the cause of the turbine trip. As information becomes available River Bend Station will provide additional information.
"This event is being reported in accordance with 10CFR50.72(b)(iv)(B) as an automatic RPS actuation with the reactor critical."
The safety relief valves momentarily lifted immediately following the scram. The plant electrical distribution system is in a normal shutdown configuration. The scram was uncomplicated.
The licensee notified the NRC Resident Inspector.
Power Reactor
Event Number: 47550
Facility: SAN ONOFRE
Region: 4 State: CA
Unit: [] [2] []
RX Type: [1] W-3-LP,[2] CE,[3] CE
NRC Notified By: DOUG FOOTE
HQ OPS Officer: DONALD NORWOOD
Region: 4 State: CA
Unit: [] [2] []
RX Type: [1] W-3-LP,[2] CE,[3] CE
NRC Notified By: DOUG FOOTE
HQ OPS Officer: DONALD NORWOOD
Notification Date: 12/23/2011
Notification Time: 15:18 [ET]
Event Date: 12/23/2011
Event Time: 05:00 [PST]
Last Update Date: 12/23/2011
Notification Time: 15:18 [ET]
Event Date: 12/23/2011
Event Time: 05:00 [PST]
Last Update Date: 12/23/2011
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(3)(xiii) - LOSS COMM/ASMT/RESPONSE
10 CFR Section:
50.72(b)(3)(xiii) - LOSS COMM/ASMT/RESPONSE
Person (Organization):
BOB HAGAR (R4DO)
BOB HAGAR (R4DO)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 2 | N | Y | 90 | Power Operation | 90 | Power Operation |
EMERGENCY RESPONSE DATA SYSTEM OUT OF SERVICE
"At 0500 PST 12/23/2011, ERDS communication VPN (Virtual Private Network) link with the NRC was interrupted during an automatic swap between computer servers.
"Restoration of the communication link is expected to be restored by 1430 PST."
The licensee will notify the NRC Resident Inspector.
"At 0500 PST 12/23/2011, ERDS communication VPN (Virtual Private Network) link with the NRC was interrupted during an automatic swap between computer servers.
"Restoration of the communication link is expected to be restored by 1430 PST."
The licensee will notify the NRC Resident Inspector.
Power Reactor
Event Number: 47551
Facility: ROBINSON
Region: 2 State: SC
Unit: [2] [] []
RX Type: [2] W-3-LP
NRC Notified By: JOSEPH TODD
HQ OPS Officer: PETE SNYDER
Region: 2 State: SC
Unit: [2] [] []
RX Type: [2] W-3-LP
NRC Notified By: JOSEPH TODD
HQ OPS Officer: PETE SNYDER
Notification Date: 12/23/2011
Notification Time: 16:54 [ET]
Event Date: 12/23/2011
Event Time: 16:20 [EST]
Last Update Date: 12/23/2011
Notification Time: 16:54 [ET]
Event Date: 12/23/2011
Event Time: 16:20 [EST]
Last Update Date: 12/23/2011
Emergency Class: ALERT
10 CFR Section:
50.72(a) (1) (i) - EMERGENCY DECLARED 50.72(b)(2)(xi) - OFFSITE NOTIFICATION
10 CFR Section:
50.72(a) (1) (i) - EMERGENCY DECLARED 50.72(b)(2)(xi) - OFFSITE NOTIFICATION
Person (Organization):
GERALD MCCOY (R2DO)
JOSEPH GIITTER (NRR)
WILLIAM GOTT (IRD)
CHUCK CASTO (R2)
ERIC LEEDS (NRR)
GERALD MCCOY (R2DO)
JOSEPH GIITTER (NRR)
WILLIAM GOTT (IRD)
CHUCK CASTO (R2)
ERIC LEEDS (NRR)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 2 | N | Y | 100 | Power Operation | 100 | Power Operation |
ALERT DECLARED DUE TO HALON DISCHARGE DURING TESTING
The licensee declared an alert condition based on the inadvertent discharge of Halon gas into their Emergency Bus Room during system testing. Plant operation was unaffected and the unit continued to operate at full power.
There were no injuries or equipment damage due to the event. The licensee observed no fire or flames in the area. The licensee evacuated the area and provided ventilation to disperse the Halon.
The licensee notified the NRC Resident Inspector. Also notified HHS (Jewel Wright).
* * * UPDATE FROM BRIAN WALDSMITH TO DONALD NORWOOD ON 12/23/11 AT 1822 EST * * *
At 1810 EST on 12/23/11, Robinson terminated the Alert condition based on a return to a habitable atmosphere in the Emergency Bus Room. "The cause for the Halon System actuation appears to have been a Human Performance Error. The test/inhibit switch was placed in the incorrect position."
"There were no radiological releases for this event."
The licensee notified state, local and other governmental agencies concerning this event. Notified R2DO (McCoy), NRR EO (Giitter), IR (Gott), DHS SWO (Arnold), FEMA (O'Connell), DOE (Jackson), USDA (Walters), and HHS(Wright).
The licensee declared an alert condition based on the inadvertent discharge of Halon gas into their Emergency Bus Room during system testing. Plant operation was unaffected and the unit continued to operate at full power.
There were no injuries or equipment damage due to the event. The licensee observed no fire or flames in the area. The licensee evacuated the area and provided ventilation to disperse the Halon.
The licensee notified the NRC Resident Inspector. Also notified HHS (Jewel Wright).
* * * UPDATE FROM BRIAN WALDSMITH TO DONALD NORWOOD ON 12/23/11 AT 1822 EST * * *
At 1810 EST on 12/23/11, Robinson terminated the Alert condition based on a return to a habitable atmosphere in the Emergency Bus Room. "The cause for the Halon System actuation appears to have been a Human Performance Error. The test/inhibit switch was placed in the incorrect position."
"There were no radiological releases for this event."
The licensee notified state, local and other governmental agencies concerning this event. Notified R2DO (McCoy), NRR EO (Giitter), IR (Gott), DHS SWO (Arnold), FEMA (O'Connell), DOE (Jackson), USDA (Walters), and HHS(Wright).