Event Notification Report for December 10, 2016
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
12/09/2016 - 12/10/2016
EVENT NUMBERS
52425
52425
Power Reactor
Event Number: 52425
Facility: NINE MILE POINT
Region: 1 State: NY
Unit: [1] [] []
RX Type: [1] GE-2,[2] GE-5
NRC Notified By: BENJAMIN ARIOLA
HQ OPS Officer: HOWIE CROUCH
Region: 1 State: NY
Unit: [1] [] []
RX Type: [1] GE-2,[2] GE-5
NRC Notified By: BENJAMIN ARIOLA
HQ OPS Officer: HOWIE CROUCH
Notification Date: 12/10/2016
Notification Time: 12:31 [ET]
Event Date: 12/10/2016
Event Time: 08:48 [EST]
Last Update Date: 12/10/2016
Notification Time: 12:31 [ET]
Event Date: 12/10/2016
Event Time: 08:48 [EST]
Last Update Date: 12/10/2016
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):
ART BURRITT (R1DO)
ART BURRITT (R1DO)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 1 | M/R | Y | 100 | Power Operation | 0 | Hot Shutdown |
MANUAL REACTOR SCRAM DUE TO HIGH MAIN TURBINE VIBRATIONS
"On December 10, 2016 at 0848 EST, [operators at] Nine Mile Point Unit 1 manually scrammed the reactor due to high vibrations on the Main Turbine. Cause of the high vibrations is being investigated.
"Following the scram, the High Pressure Coolant Injection (HPCI) system automatically initiated as expected. At Nine Mile Point Unit 1, a HPCI system actuation signal on low reactor pressure vessel (RPV) level is normally received following a reactor scram, due to level shrink. HPCI is a flow control mode of the normal feedwater system and is not an emergency core cooling system. At 0849, 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. 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 state of New York Public Service Commission and the NRC Resident Inspector.
"On December 10, 2016 at 0848 EST, [operators at] Nine Mile Point Unit 1 manually scrammed the reactor due to high vibrations on the Main Turbine. Cause of the high vibrations is being investigated.
"Following the scram, the High Pressure Coolant Injection (HPCI) system automatically initiated as expected. At Nine Mile Point Unit 1, a HPCI system actuation signal on low reactor pressure vessel (RPV) level is normally received following a reactor scram, due to level shrink. HPCI is a flow control mode of the normal feedwater system and is not an emergency core cooling system. At 0849, 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. 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 state of New York Public Service Commission and the NRC Resident Inspector.