Event Notification Report for February 27, 2010
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
02/26/2010 - 02/27/2010
EVENT NUMBERS
45732
Power Reactor
Event Number: 45732
Facility: BRUNSWICK
Region: 2 State: NC
Unit: [1] [] []
RX Type: [1] GE-4,[2] GE-4
NRC Notified By: JERRY PIERCE
HQ OPS Officer: STEVE SANDIN
Region: 2 State: NC
Unit: [1] [] []
RX Type: [1] GE-4,[2] GE-4
NRC Notified By: JERRY PIERCE
HQ OPS Officer: STEVE SANDIN
Notification Date: 02/27/2010
Notification Time: 07:37 [ET]
Event Date: 02/27/2010
Event Time: 01:58 [EST]
Last Update Date: 02/27/2010
Notification Time: 07:37 [ET]
Event Date: 02/27/2010
Event Time: 01:58 [EST]
Last Update Date: 02/27/2010
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(3)(iv)(A) - VALID SPECIF SYS ACTUATION
10 CFR Section:
50.72(b)(3)(iv)(A) - VALID SPECIF SYS ACTUATION
Person (Organization):
BRIAN BONSER (R2DO)
BRIAN BONSER (R2DO)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 1 | N | N | 0 | Hot Shutdown | 0 | Hot Shutdown |
REACTOR CORE ISOLATION COOLING (RCIC) SYSTEM MANUALLY STARTED TO MAINTAIN REACTOR PRESSURE VESSEL LEVEL FOLLOWING A PRE-PLANNED REACTOR SCRAM
"On February 27, 2010, at 0116 hours, as part of a pre-planned sequence of events, Unit 1 control room operators manually inserted a Reactor Protection system trip to shut down the reactor from approximately 21 percent of rated thermal power to begin a planned refuel outage. At 0158 hours, the Reactor Core Isolation Cooling (RCIC) system was manually started to maintain reactor pressure vessel (RPV) coolant level after the 1A Reactor Feedwater Pump (RFP) was shutdown due to high turbine casing drain level, and the 1B Reactor Feedwater Pump (RFP) had been removed from service and isolated to support maintenance activities. The Reactor Core Isolation Cooling (RCIC) system started and maintained reactor pressure vessel (RPV) coolant level until the 1B Reactor Feedwater Pump (RFP) could be returned to service at 0248 [hours]. The Reactor Core Isolation Cooling (RCIC) system was shutdown at 0306 [hours].
"The safety significance of this occurrence is considered minimal. The RCIC system is designed to operate either automatically or manually following RPV isolation, accompanied by a loss of normal coolant flow from the Reactor Feedwater system, to provide adequate core cooling, and control of the RPV coolant level. The function of the RCIC system is to respond to transient events by providing makeup coolant to the reactor. For this event, the RPV was not isolated, but there was a loss of normal coolant flow from the Reactor Feedwater System. The RCIC system was manually started and successfully controlled RPV coolant level for approximately 68 minutes until Reactor Feedwater system flow could be restored to the RPV. All emergency core cooling systems were operable and ready for use, if needed, during this event. This transient is bounded by the analyses in the Updated Final Safety Analysis Report."
RPV level remained in the normal post-shutdown band of 170-200 inches during the transient. The licensee informed the NRC Resident Inspector.
"On February 27, 2010, at 0116 hours, as part of a pre-planned sequence of events, Unit 1 control room operators manually inserted a Reactor Protection system trip to shut down the reactor from approximately 21 percent of rated thermal power to begin a planned refuel outage. At 0158 hours, the Reactor Core Isolation Cooling (RCIC) system was manually started to maintain reactor pressure vessel (RPV) coolant level after the 1A Reactor Feedwater Pump (RFP) was shutdown due to high turbine casing drain level, and the 1B Reactor Feedwater Pump (RFP) had been removed from service and isolated to support maintenance activities. The Reactor Core Isolation Cooling (RCIC) system started and maintained reactor pressure vessel (RPV) coolant level until the 1B Reactor Feedwater Pump (RFP) could be returned to service at 0248 [hours]. The Reactor Core Isolation Cooling (RCIC) system was shutdown at 0306 [hours].
"The safety significance of this occurrence is considered minimal. The RCIC system is designed to operate either automatically or manually following RPV isolation, accompanied by a loss of normal coolant flow from the Reactor Feedwater system, to provide adequate core cooling, and control of the RPV coolant level. The function of the RCIC system is to respond to transient events by providing makeup coolant to the reactor. For this event, the RPV was not isolated, but there was a loss of normal coolant flow from the Reactor Feedwater System. The RCIC system was manually started and successfully controlled RPV coolant level for approximately 68 minutes until Reactor Feedwater system flow could be restored to the RPV. All emergency core cooling systems were operable and ready for use, if needed, during this event. This transient is bounded by the analyses in the Updated Final Safety Analysis Report."
RPV level remained in the normal post-shutdown band of 170-200 inches during the transient. The licensee informed the NRC Resident Inspector.