Event Notification Report for October 08, 2016
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
10/07/2016 - 10/08/2016
Power Reactor
Event Number: 52290
Facility: ROBINSON
Region: 2 State: SC
Unit: [2] [] []
RX Type: [2] W-3-LP
NRC Notified By: MARTIN BOWSKILL
HQ OPS Officer: DANIEL MILLS
Region: 2 State: SC
Unit: [2] [] []
RX Type: [2] W-3-LP
NRC Notified By: MARTIN BOWSKILL
HQ OPS Officer: DANIEL MILLS
Notification Date: 10/08/2016
Notification Time: 13:44 [ET]
Event Date: 10/08/2016
Event Time: 13:17 [EDT]
Last Update Date: 10/09/2016
Notification Time: 13:44 [ET]
Event Date: 10/08/2016
Event Time: 13:17 [EDT]
Last Update Date: 10/09/2016
Emergency Class: UNUSUAL EVENT
10 CFR Section:
50.72(a) (1) (i) - EMERGENCY DECLARED 50.72(b)(2)(iv)(B) - RPS ACTUATION - CRITICAL 50.72(b)(3)(iv)(A) - VALID SPECIF SYS ACTUATION
10 CFR Section:
50.72(a) (1) (i) - EMERGENCY DECLARED 50.72(b)(2)(iv)(B) - RPS ACTUATION - CRITICAL 50.72(b)(3)(iv)(A) - VALID SPECIF SYS ACTUATION
Person (Organization):
BRIAN BONSER (R2DO)
JEFFERY GRANT (IRD)
CATHY HANEY (R2RA)
BRIAN McDERMOTT (NRR)
BRIAN BONSER (R2DO)
JEFFERY GRANT (IRD)
CATHY HANEY (R2RA)
BRIAN McDERMOTT (NRR)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 2 | A/R | Y | 100 | Power Operation | 0 | Hot Standby |
UNUSUAL EVENT DECLARED DUE TO LOSS OF OFFSITE POWER
"UE SU1.1 declared due to momentary loss of power from the qualified off-site source. Both Emergency Diesel Generators started and loaded to supply power to both of the Emergency Buses.
"'A' Service Water Pump did not start on Blackout sequencer. Sufficient Service Water flow is available from the other three operating pumps. All other systems operated as designed."
At 1304 EDT Robinson Unit 2 experienced a momentary grid voltage drop that lowered the 4kV bus voltage and initiated an automatic reactor trip. All rods inserted and decay heat is being removed by steam generator PORVs. In response to the reduced bus voltage, the Emergency Diesel Generators (EDGs) automatically started and loaded onto the emergency busses. At 1317 EDT, the licensee declared an Unusual Event (EAL SU1.1) due to the loss of offsite power. The licensee is currently investigating the cause of the grid voltage instability. The emergency busses will continue to be powered by the EDGs until the licensee has determined the cause for the voltage drop. All offsite power sources and all equipment is available. The licensee has notified the state government and Darlington County. The NRC Resident Inspector has been notified.
Notified DHS SWO, FEMA OPS Center, FEMA National Watch (email only), DHS NICC, Nuclear SSA (email only).
* * * UPDATE FROM ALEX CURLINGTON TO DANIEL MILLS AT 1658 EDT on 10/08/16 * * *
"At 1303 EDT on 10/08/2016, a reactor trip occurred. The cause was under voltage to the plant 4kV buses due to an offsite grid disturbance. The cause of the disturbance is under investigation. Following the reactor trip, the Auxiliary Feedwater System actuated as expected on low steam generator level. At the time of the trip, the plant was in Mode 1. Currently, the Plant is in Mode 3. The current RCS Temperature is 550 degrees F (Average), and the Steam Generator Levels are in the range of 42 to 53% (normal range) with levels controlled by the Auxiliary Feedwater System. Decay heat removal is being controlled by the steam generator PORVs. 'A' Service Water Pump did not start on Blackout sequencer. Sufficient Service Water flow is available from the other three operating service water pumps 'B', 'C', and 'D'. All other systems operated as designed.
"Due to the Automatic Actuation of the Reactor Protection System, this event is being reported as a 4-hour Non-Emergency per 10 CFR 50.72(b)(2)(iv)(B). Due to the valid actuation of Auxiliary Feedwater System, this event is also being reported as an 8-hour Non-Emergency per 10 CFR 50.72(b)(3)(iv)(A)(B)(6). At no time during this occurrence was the public or plant staff at risk as a result of this event.
"The Resident Inspector has been notified."
* * * UPDATE FROM BOBBY STUCKEY TO DANIEL MILLS AT 2347 EDT on 10/08/16 * * *
"At 2323 [EDT] Emergency Bus E-2 powered from off-site power."
The NRC Resident Inspector will be notified.
Notified R2DO (Bonser), IRD (Grant), NRR EO (Miller).
* * * UPDATE FROM BOBBY STUCKEY TO JOHN SHOEMAKER AT 0028 EDT ON 10/09/16 * * *
"At 0011 [EDT] Robinson Nuclear Plant has terminated the Unusual Event."
Basis for the Unusual Event termination was restoration of power to Emergency Bus E-2 from off-site power.
The licensee has notified the NRC Resident Inspector.
Notified R2DO (Bonser), NRR EO (Miller), IRD (Grant), DHS SWO, FEMA OPS Center, FEMA National Watch (email only), DHS NICC, Nuclear SSA (email only).
* * * UPDATE FROM GEORGE CURTIS TO JOHN SHOEMAKER AT 0253 EDT ON 10/09/16 * * *
"At approximately 2323 EDT on 10/08/2016, an auto-start of the Auxiliary Feedwater (AFW) Motor-Driven pumps occurred during the transfer of Emergency Bus power from the 'B' Emergency Diesel Generator (EDG) to offsite power. AFW system auto-start logic associated with Main Feed Pump (MFP) breakers being open is defeated when the EDG output breaker is closed. As such, when the EDG output breaker was opened during the power transfer while the MFP breakers were open, the auto-start logic was thereby met causing the AFW auto-start.
"Due to the valid actuation of the AFW System, this event is being reported as an 8-hour Non-Emergency per 10 CFR 50.72(b)(3)(iv)(A). At no time did this occurrence pose undue risk to the health and safety of the public.
"The NRC Senior Resident Inspector has been notified of this event."
H.B. Robinson Unit 2 was in Mode 3 during this event. Notified R2DO (Bonser).
"UE SU1.1 declared due to momentary loss of power from the qualified off-site source. Both Emergency Diesel Generators started and loaded to supply power to both of the Emergency Buses.
"'A' Service Water Pump did not start on Blackout sequencer. Sufficient Service Water flow is available from the other three operating pumps. All other systems operated as designed."
At 1304 EDT Robinson Unit 2 experienced a momentary grid voltage drop that lowered the 4kV bus voltage and initiated an automatic reactor trip. All rods inserted and decay heat is being removed by steam generator PORVs. In response to the reduced bus voltage, the Emergency Diesel Generators (EDGs) automatically started and loaded onto the emergency busses. At 1317 EDT, the licensee declared an Unusual Event (EAL SU1.1) due to the loss of offsite power. The licensee is currently investigating the cause of the grid voltage instability. The emergency busses will continue to be powered by the EDGs until the licensee has determined the cause for the voltage drop. All offsite power sources and all equipment is available. The licensee has notified the state government and Darlington County. The NRC Resident Inspector has been notified.
Notified DHS SWO, FEMA OPS Center, FEMA National Watch (email only), DHS NICC, Nuclear SSA (email only).
* * * UPDATE FROM ALEX CURLINGTON TO DANIEL MILLS AT 1658 EDT on 10/08/16 * * *
"At 1303 EDT on 10/08/2016, a reactor trip occurred. The cause was under voltage to the plant 4kV buses due to an offsite grid disturbance. The cause of the disturbance is under investigation. Following the reactor trip, the Auxiliary Feedwater System actuated as expected on low steam generator level. At the time of the trip, the plant was in Mode 1. Currently, the Plant is in Mode 3. The current RCS Temperature is 550 degrees F (Average), and the Steam Generator Levels are in the range of 42 to 53% (normal range) with levels controlled by the Auxiliary Feedwater System. Decay heat removal is being controlled by the steam generator PORVs. 'A' Service Water Pump did not start on Blackout sequencer. Sufficient Service Water flow is available from the other three operating service water pumps 'B', 'C', and 'D'. All other systems operated as designed.
"Due to the Automatic Actuation of the Reactor Protection System, this event is being reported as a 4-hour Non-Emergency per 10 CFR 50.72(b)(2)(iv)(B). Due to the valid actuation of Auxiliary Feedwater System, this event is also being reported as an 8-hour Non-Emergency per 10 CFR 50.72(b)(3)(iv)(A)(B)(6). At no time during this occurrence was the public or plant staff at risk as a result of this event.
"The Resident Inspector has been notified."
* * * UPDATE FROM BOBBY STUCKEY TO DANIEL MILLS AT 2347 EDT on 10/08/16 * * *
"At 2323 [EDT] Emergency Bus E-2 powered from off-site power."
The NRC Resident Inspector will be notified.
Notified R2DO (Bonser), IRD (Grant), NRR EO (Miller).
* * * UPDATE FROM BOBBY STUCKEY TO JOHN SHOEMAKER AT 0028 EDT ON 10/09/16 * * *
"At 0011 [EDT] Robinson Nuclear Plant has terminated the Unusual Event."
Basis for the Unusual Event termination was restoration of power to Emergency Bus E-2 from off-site power.
The licensee has notified the NRC Resident Inspector.
Notified R2DO (Bonser), NRR EO (Miller), IRD (Grant), DHS SWO, FEMA OPS Center, FEMA National Watch (email only), DHS NICC, Nuclear SSA (email only).
* * * UPDATE FROM GEORGE CURTIS TO JOHN SHOEMAKER AT 0253 EDT ON 10/09/16 * * *
"At approximately 2323 EDT on 10/08/2016, an auto-start of the Auxiliary Feedwater (AFW) Motor-Driven pumps occurred during the transfer of Emergency Bus power from the 'B' Emergency Diesel Generator (EDG) to offsite power. AFW system auto-start logic associated with Main Feed Pump (MFP) breakers being open is defeated when the EDG output breaker is closed. As such, when the EDG output breaker was opened during the power transfer while the MFP breakers were open, the auto-start logic was thereby met causing the AFW auto-start.
"Due to the valid actuation of the AFW System, this event is being reported as an 8-hour Non-Emergency per 10 CFR 50.72(b)(3)(iv)(A). At no time did this occurrence pose undue risk to the health and safety of the public.
"The NRC Senior Resident Inspector has been notified of this event."
H.B. Robinson Unit 2 was in Mode 3 during this event. Notified R2DO (Bonser).
Power Reactor
Event Number: 52291
Facility: HARRIS
Region: 2 State: NC
Unit: [1] [] []
RX Type: [1] W-3-LP
NRC Notified By: JOEL DUHON
HQ OPS Officer: DANIEL MILLS
Region: 2 State: NC
Unit: [1] [] []
RX Type: [1] W-3-LP
NRC Notified By: JOEL DUHON
HQ OPS Officer: DANIEL MILLS
Notification Date: 10/08/2016
Notification Time: 14:23 [ET]
Event Date: 10/08/2016
Event Time: 13:28 [EDT]
Last Update Date: 10/10/2016
Notification Time: 14:23 [ET]
Event Date: 10/08/2016
Event Time: 13:28 [EDT]
Last Update Date: 10/10/2016
Emergency Class: UNUSUAL EVENT
10 CFR Section:
50.72(a) (1) (i) - EMERGENCY DECLARED 50.72(b)(3)(iv)(A) - VALID SPECIF SYS ACTUATION 50.72(b)(3)(xiii) - LOSS COMM/ASMT/RESPONSE 50.72(b)(3)(v)(D) - ACCIDENT MITIGATION
10 CFR Section:
50.72(a) (1) (i) - EMERGENCY DECLARED 50.72(b)(3)(iv)(A) - VALID SPECIF SYS ACTUATION 50.72(b)(3)(xiii) - LOSS COMM/ASMT/RESPONSE 50.72(b)(3)(v)(D) - ACCIDENT MITIGATION
Person (Organization):
BRIAN BONSER (R2DO)
JEFFERY GRANT (IRD)
CATHY HANEY (R2RA)
BRIAN McDERMOTT (NRR)
BRIAN BONSER (R2DO)
JEFFERY GRANT (IRD)
CATHY HANEY (R2RA)
BRIAN McDERMOTT (NRR)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 1 | N | N | 0 | Hot Shutdown | 0 | Hot Shutdown |
UNUSUAL EVENT DECLARED DUE TO LOSS OF OFFSITE POWER
"Loss of all offsite power capability, Table S-5, to 6.9kV emergency buses 1A-SA and 1B-SB for greater than or equal to 15 minutes."
At 1328 EDT, while shutdown in Mode 4 (Hot Shutdown), Harris declared an Unusual Event due to a loss of offsite power. Following the loss of offsite power (LOOP), the Emergency Diesel Generators started and loaded onto their respective emergency buses. The reactor remains stable and shutdown in Mode 4. The licensee is currently investigating the cause of the LOOP and the emergency buses will continue to be powered by the EDGs until the licensee has determined the cause for the LOOP. Offsite power is currently available into the switchyard. The licensee notified the state government, the local government, and the NRC Resident Inspector.
Notified DHS SWO, FEMA OPS Center, FEMA National Watch (email only), DHS NICC, Nuclear SSA (email only).
* * * UPDATE FROM RALPH DOWNEY TO DONALD NORWOOD AT 1658 EDT ON 10/8/16 * * *
"The cause [of the LOOP] is not known. Duke Energy Control Center has evaluated the grid and is comfortable with Harris connecting emergency buses back to the grid. Harris Plant is evaluating restoration. Faults were validated on the 115kV Cape Fear North and South supply lines into the Harris switchyard.
"This notification also addresses various valid actuations of safety systems, including the Emergency Diesel Generators, as well as, potential loss of Emergency Assessment Capabilities due to the LOOP impacting Emergency Planning equipment."
The licensee notified the NRC Resident Inspector.
Notified R2DO (Bonser), IRD (Grant), and NRR EO (King).
* * * UPDATE FROM RALPH DOWNEY TO DONALD NORWOOD AT 1755 EDT ON 10/8/16 * * *
The cause of the LOOP has been determined to be a momentary electricity loss on the 115kV Cape Fear North and South supply lines into the Harris switchyard.
"This event notification also addresses the loss of safety function of the offsite power system which occurred as a result of grid perturbations."
The licensee notified the NRC Resident Inspector.
Notified R2DO (Bonser), IRD (Grant), and NRR EO (King).
* * * UPDATE FROM DUSTIN MARTIN TO DONALD NORWOOD AT 2055 EDT ON 10/8/16 * * *
Based on the grid being stable and the 115kV Cape Fear North and South lines being available, the licensee terminated the Unusual Event at 2049 EDT on 10/8/16.
The licensee notified the NRC Resident Inspector.
Notified R2DO (Bonser), IRD (Grant), and NRR EO (King). Notified DHS SWO, FEMA OPS Center, FEMA National Watch (email only), DHS NICC, Nuclear SSA (email only).
* * * UPDATE FROM SARAH McDANIEL TO DONALD NORWOOD AT 1330 EDT ON 10/9/16 * * *
10 CFR 50.72(b)(2)(XI) - OFFSITE NOTIFICATION
"At approximately 1305 EDT on October 9, 2016, Duke Energy personnel notified the North Carolina Department of Environment and Natural Resources of a spill of untreated sanitary wastewater. During a significant rainfall event associated with Hurricane Matthew, wastewater was released from the overflow of a lift station that did not function as a result of a power outage. The untreated sanitary wastewater entered the plant's storm drain system. The release has been stopped and the lift station power is restored. An investigation is in progress to further determine the cause and additional corrective actions.
"There is no impact to public health and safety or the environment due to this incident.
"This event is reportable per 10 CFR 50.72(b)(2)(xi), an event related to protection of the environment for which a notification to other government agencies has been made.
"The NRC Resident Inspector has been notified."
Notified R2DO (Bonser).
"Loss of all offsite power capability, Table S-5, to 6.9kV emergency buses 1A-SA and 1B-SB for greater than or equal to 15 minutes."
At 1328 EDT, while shutdown in Mode 4 (Hot Shutdown), Harris declared an Unusual Event due to a loss of offsite power. Following the loss of offsite power (LOOP), the Emergency Diesel Generators started and loaded onto their respective emergency buses. The reactor remains stable and shutdown in Mode 4. The licensee is currently investigating the cause of the LOOP and the emergency buses will continue to be powered by the EDGs until the licensee has determined the cause for the LOOP. Offsite power is currently available into the switchyard. The licensee notified the state government, the local government, and the NRC Resident Inspector.
Notified DHS SWO, FEMA OPS Center, FEMA National Watch (email only), DHS NICC, Nuclear SSA (email only).
* * * UPDATE FROM RALPH DOWNEY TO DONALD NORWOOD AT 1658 EDT ON 10/8/16 * * *
"The cause [of the LOOP] is not known. Duke Energy Control Center has evaluated the grid and is comfortable with Harris connecting emergency buses back to the grid. Harris Plant is evaluating restoration. Faults were validated on the 115kV Cape Fear North and South supply lines into the Harris switchyard.
"This notification also addresses various valid actuations of safety systems, including the Emergency Diesel Generators, as well as, potential loss of Emergency Assessment Capabilities due to the LOOP impacting Emergency Planning equipment."
The licensee notified the NRC Resident Inspector.
Notified R2DO (Bonser), IRD (Grant), and NRR EO (King).
* * * UPDATE FROM RALPH DOWNEY TO DONALD NORWOOD AT 1755 EDT ON 10/8/16 * * *
The cause of the LOOP has been determined to be a momentary electricity loss on the 115kV Cape Fear North and South supply lines into the Harris switchyard.
"This event notification also addresses the loss of safety function of the offsite power system which occurred as a result of grid perturbations."
The licensee notified the NRC Resident Inspector.
Notified R2DO (Bonser), IRD (Grant), and NRR EO (King).
* * * UPDATE FROM DUSTIN MARTIN TO DONALD NORWOOD AT 2055 EDT ON 10/8/16 * * *
Based on the grid being stable and the 115kV Cape Fear North and South lines being available, the licensee terminated the Unusual Event at 2049 EDT on 10/8/16.
The licensee notified the NRC Resident Inspector.
Notified R2DO (Bonser), IRD (Grant), and NRR EO (King). Notified DHS SWO, FEMA OPS Center, FEMA National Watch (email only), DHS NICC, Nuclear SSA (email only).
* * * UPDATE FROM SARAH McDANIEL TO DONALD NORWOOD AT 1330 EDT ON 10/9/16 * * *
10 CFR 50.72(b)(2)(XI) - OFFSITE NOTIFICATION
"At approximately 1305 EDT on October 9, 2016, Duke Energy personnel notified the North Carolina Department of Environment and Natural Resources of a spill of untreated sanitary wastewater. During a significant rainfall event associated with Hurricane Matthew, wastewater was released from the overflow of a lift station that did not function as a result of a power outage. The untreated sanitary wastewater entered the plant's storm drain system. The release has been stopped and the lift station power is restored. An investigation is in progress to further determine the cause and additional corrective actions.
"There is no impact to public health and safety or the environment due to this incident.
"This event is reportable per 10 CFR 50.72(b)(2)(xi), an event related to protection of the environment for which a notification to other government agencies has been made.
"The NRC Resident Inspector has been notified."
Notified R2DO (Bonser).
Power Reactor
Event Number: 52289
Facility: HARRIS
Region: 2 State: NC
Unit: [1] [] []
RX Type: [1] W-3-LP
NRC Notified By: JOHN CAVES
HQ OPS Officer: JOHN SHOEMAKER
Region: 2 State: NC
Unit: [1] [] []
RX Type: [1] W-3-LP
NRC Notified By: JOHN CAVES
HQ OPS Officer: JOHN SHOEMAKER
Notification Date: 10/08/2016
Notification Time: 05:47 [ET]
Event Date: 10/08/2016
Event Time: 01:50 [EDT]
Last Update Date: 10/08/2016
Notification Time: 05:47 [ET]
Event Date: 10/08/2016
Event Time: 01:50 [EDT]
Last Update Date: 10/08/2016
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(2)(iv)(A) - ECCS INJECTION 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)(A) - ECCS INJECTION 50.72(b)(2)(iv)(B) - RPS ACTUATION - CRITICAL 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 | A/R | Y | 7 | Power Operation | 0 | Hot Standby |
UNPLANNED REACTOR TRIP AND SAFETY INJECTION DUE TO TURBINE CONTROL VALVE TRANSIENT
"On October 8, 2016, while reducing power for a planned refueling outage, the unit was taken offline by opening the main generator output breakers. With the reactor at approximately 7 percent power in MODE 1, an unplanned actuation of the reactor protection system occurred. At 0150 [EDT], an unexpected steam valve transient occurred while main turbine valve control was being transferred from throttle valve to governor valves during main turbine overspeed testing. This resulted in an automatic low steamline pressure Safety Injection and Reactor Trip. All safety systems functioned as expected. The operations staff responded to the event in accordance with applicable plant procedures. The plant stabilized at normal operating no-load reactor coolant system (RCS) temperature and pressure following the reactor trip, with decay heat being removed using steam generator power operated relief valves. Steam generator water levels are being maintained using auxiliary feedwater. All emergency core cooling system (ECCS) equipment is available.
"The cause of the steam valve transient is under investigation. This condition is being reported as an ECCS discharge to RCS, an unplanned reactor protection system actuation, and a specified system actuation in accordance with 10 CFR 50.72(b)(2)(iv)(A), 10 CFR 50.72(b)(2)(iv)(B). and 10 CFR 50.72(b)(3)(iv)(A).
"This condition does not affect the health and safety of the public or station employees. The NRC Resident Inspector has been notified."
The Safety Injection occurred for approximately 6 minutes and Pressurizer level increased to approximately 71%. The Main Steam Isolation Valves closed as a result of the Safety Injection and Decay Heat is being removed using the Steam Generator Atmospheric Relief Valves. There is no known primary to secondary leakage.
"On October 8, 2016, while reducing power for a planned refueling outage, the unit was taken offline by opening the main generator output breakers. With the reactor at approximately 7 percent power in MODE 1, an unplanned actuation of the reactor protection system occurred. At 0150 [EDT], an unexpected steam valve transient occurred while main turbine valve control was being transferred from throttle valve to governor valves during main turbine overspeed testing. This resulted in an automatic low steamline pressure Safety Injection and Reactor Trip. All safety systems functioned as expected. The operations staff responded to the event in accordance with applicable plant procedures. The plant stabilized at normal operating no-load reactor coolant system (RCS) temperature and pressure following the reactor trip, with decay heat being removed using steam generator power operated relief valves. Steam generator water levels are being maintained using auxiliary feedwater. All emergency core cooling system (ECCS) equipment is available.
"The cause of the steam valve transient is under investigation. This condition is being reported as an ECCS discharge to RCS, an unplanned reactor protection system actuation, and a specified system actuation in accordance with 10 CFR 50.72(b)(2)(iv)(A), 10 CFR 50.72(b)(2)(iv)(B). and 10 CFR 50.72(b)(3)(iv)(A).
"This condition does not affect the health and safety of the public or station employees. The NRC Resident Inspector has been notified."
The Safety Injection occurred for approximately 6 minutes and Pressurizer level increased to approximately 71%. The Main Steam Isolation Valves closed as a result of the Safety Injection and Decay Heat is being removed using the Steam Generator Atmospheric Relief Valves. There is no known primary to secondary leakage.