Event Notification Report for November 03, 2012
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
11/02/2012 - 11/03/2012
EVENT NUMBERS
48477
Power Reactor
Event Number: 48477
Facility: NINE MILE POINT
Region: 1 State: NY
Unit: [1] [] []
RX Type: [1] GE-2,[2] GE-5
NRC Notified By: MATTHEW BUSCH
HQ OPS Officer: JOHN KNOKE
Region: 1 State: NY
Unit: [1] [] []
RX Type: [1] GE-2,[2] GE-5
NRC Notified By: MATTHEW BUSCH
HQ OPS Officer: JOHN KNOKE
Notification Date: 11/03/2012
Notification Time: 11:50 [ET]
Event Date: 11/03/2012
Event Time: 08:23 [EDT]
Last Update Date: 11/03/2012
Notification Time: 11:50 [ET]
Event Date: 11/03/2012
Event Time: 08:23 [EDT]
Last Update Date: 11/03/2012
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):
JAMES NOGGLE (R1DO)
JAMES NOGGLE (R1DO)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 1 | A/R | Y | 24 | Power Operation | 0 | Hot Shutdown |
AUTOMATIC SCRAM ON LOW REACTOR WATER LEVEL
"On November 3, 2012 at 0823 EDT, Nine Mile Point Unit 1 experienced an automatic reactor scram on low reactor water level. All control rods fully inserted and all plant systems responded per design following the scram. Prior to the automatic scram, an unexpected high Reactor Pressure Vessel (RPV) water level was experienced, followed by a turbine trip and subsequent lowering of RPV water level to the RPV low level scram set point. The cause of the water level transient is unknown.
"Following the automatic scram, the High Pressure Coolant Injection (HPCI) System automatically initiated as expected. HPCI is a flow control mode of the normal feedwater systems, and is not an Emergency Core Cooling System. At 0824 EDT, RPV level was restored above the HPCI System low level actuation set point and the HPCI System initiation signal was reset. Pressure control was established on the Turbine Bypass Valves, the preferred system. No Electromatic Relief Valves actuated due to this scram.
"Nine Mile Point Unit 1 is currently in Hot Shutdown, with reactor water level and pressure maintained within normal bands. Since the scram, there have been no anomalies observed with feedwater system operation. Decay heat is being removed via steam to the main condenser using the bypass valves. The offsite grid is stable with no grid restrictions or warnings in effect. The unit is currently implementing post scram recovery procedures.
"The licensee has notified the NRC Resident Inspector."
Unit 2 was not affected during this event.
"On November 3, 2012 at 0823 EDT, Nine Mile Point Unit 1 experienced an automatic reactor scram on low reactor water level. All control rods fully inserted and all plant systems responded per design following the scram. Prior to the automatic scram, an unexpected high Reactor Pressure Vessel (RPV) water level was experienced, followed by a turbine trip and subsequent lowering of RPV water level to the RPV low level scram set point. The cause of the water level transient is unknown.
"Following the automatic scram, the High Pressure Coolant Injection (HPCI) System automatically initiated as expected. HPCI is a flow control mode of the normal feedwater systems, and is not an Emergency Core Cooling System. At 0824 EDT, RPV level was restored above the HPCI System low level actuation set point and the HPCI System initiation signal was reset. Pressure control was established on the Turbine Bypass Valves, the preferred system. No Electromatic Relief Valves actuated due to this scram.
"Nine Mile Point Unit 1 is currently in Hot Shutdown, with reactor water level and pressure maintained within normal bands. Since the scram, there have been no anomalies observed with feedwater system operation. Decay heat is being removed via steam to the main condenser using the bypass valves. The offsite grid is stable with no grid restrictions or warnings in effect. The unit is currently implementing post scram recovery procedures.
"The licensee has notified the NRC Resident Inspector."
Unit 2 was not affected during this event.