Event Notification Report for February 23, 2019
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
02/22/2019 - 02/23/2019
Power Reactor
Event Number: 53893
Facility: HATCH
Region: 2 State: GA
Unit: [] [2] []
RX Type: [1] GE-4,[2] GE-4
NRC Notified By: ANDREW BELCHER
HQ OPS Officer: ANDREW WAUGH
Region: 2 State: GA
Unit: [] [2] []
RX Type: [1] GE-4,[2] GE-4
NRC Notified By: ANDREW BELCHER
HQ OPS Officer: ANDREW WAUGH
Notification Date: 02/23/2019
Notification Time: 09:13 [ET]
Event Date: 02/23/2019
Event Time: 02:12 [EST]
Last Update Date: 02/23/2019
Notification Time: 09:13 [ET]
Event Date: 02/23/2019
Event Time: 02:12 [EST]
Last Update Date: 02/23/2019
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):
RANDY MUSSER (R2DO)
RANDY MUSSER (R2DO)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 2 | N | N | 0 | Refueling | 0 | Refueling |
AUTOMATIC ACTUATION OF 2C EMERGENCY DIESEL GENERATOR
"At 0212 EST on February 23, 2019, with Unit 2 in Mode 5, an actuation signal for the 2C Emergency Diesel Generator (EDG) was received during the Loss of Coolant Accident / Loss of Offsite Power logic system functional test. The 2C EDG was running and tied onto the 2G 4160 emergency bus when the alternate supply breaker was closed as required per the test procedure. Immediately upon closing the alternate supply breaker, both the alternate supply breaker and 2C EDG output breaker tripped open. The 2C EDG output breaker reclosed once the 2G 4160 bus undervoltage relays sensed a deenergized bus. When the 2C EDG tied to the 2G 4160 bus, the bus voltage was noted as being high, and the 2C EDG was secured. Investigation is ongoing to determine the cause of the initial bus undervoltage and the subsequent bus excessive voltage.
"This event is being reported in accordance with 10 CFR 50.72(b)(3)(iv)(A) as an event that results in a valid actuation of the emergency AC power system.
"There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified."
This event puts Unit 1 in a 72 hour Limiting Condition for Operation for the 1C Startup Transformer being out of service.
"At 0212 EST on February 23, 2019, with Unit 2 in Mode 5, an actuation signal for the 2C Emergency Diesel Generator (EDG) was received during the Loss of Coolant Accident / Loss of Offsite Power logic system functional test. The 2C EDG was running and tied onto the 2G 4160 emergency bus when the alternate supply breaker was closed as required per the test procedure. Immediately upon closing the alternate supply breaker, both the alternate supply breaker and 2C EDG output breaker tripped open. The 2C EDG output breaker reclosed once the 2G 4160 bus undervoltage relays sensed a deenergized bus. When the 2C EDG tied to the 2G 4160 bus, the bus voltage was noted as being high, and the 2C EDG was secured. Investigation is ongoing to determine the cause of the initial bus undervoltage and the subsequent bus excessive voltage.
"This event is being reported in accordance with 10 CFR 50.72(b)(3)(iv)(A) as an event that results in a valid actuation of the emergency AC power system.
"There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector has been notified."
This event puts Unit 1 in a 72 hour Limiting Condition for Operation for the 1C Startup Transformer being out of service.
Power Reactor
Event Number: 53894
Facility: GRAND GULF
Region: 4 State: MS
Unit: [1] [] []
RX Type: [1] GE-6
NRC Notified By: GABRIEL HARGROVE
HQ OPS Officer: MARK ABRAMOVITZ
Region: 4 State: MS
Unit: [1] [] []
RX Type: [1] GE-6
NRC Notified By: GABRIEL HARGROVE
HQ OPS Officer: MARK ABRAMOVITZ
Notification Date: 02/23/2019
Notification Time: 19:05 [ET]
Event Date: 02/23/2019
Event Time: 14:58 [CST]
Last Update Date: 02/23/2019
Notification Time: 19:05 [ET]
Event Date: 02/23/2019
Event Time: 14:58 [CST]
Last Update Date: 02/23/2019
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):
RICK DEESE (R4DO)
RICK DEESE (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 AFTER TURBINE CONTROL VALVE FAST CLOSURE
"Actuation of RPS [Reactor Protection System] with the reactor critical. Reactor scram occurred at 1458 [CST] on 2/23/2019 from 100% power. The cause of the scram was due to Turbine Control Valve Fast Closure.
"All control rods are fully inserted. Currently reactor water level is being maintained by the Condensate Feedwater System in normal band and reactor pressure is being controlled via Main Turbine Bypass valves to the main condenser. No ECCS [Emergency Core Cooling System] initiation signals were reached and no ECCS or Diesel Generator initiation occurred.
"The Low-Low Set function of the Safety Relief Valves actuated upon turbine trip. This was reset when pressure was established on main turbine bypass valves.
"The cause of the turbine trip is still under investigation.
"There were no complications with scram response."
The licensee notified the NRC Resident Inspector.
There was no maintenance occurring on the main turbine at the time of the scram.
"Actuation of RPS [Reactor Protection System] with the reactor critical. Reactor scram occurred at 1458 [CST] on 2/23/2019 from 100% power. The cause of the scram was due to Turbine Control Valve Fast Closure.
"All control rods are fully inserted. Currently reactor water level is being maintained by the Condensate Feedwater System in normal band and reactor pressure is being controlled via Main Turbine Bypass valves to the main condenser. No ECCS [Emergency Core Cooling System] initiation signals were reached and no ECCS or Diesel Generator initiation occurred.
"The Low-Low Set function of the Safety Relief Valves actuated upon turbine trip. This was reset when pressure was established on main turbine bypass valves.
"The cause of the turbine trip is still under investigation.
"There were no complications with scram response."
The licensee notified the NRC Resident Inspector.
There was no maintenance occurring on the main turbine at the time of the scram.