Event Notification Report for April 24, 1999
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
04/23/1999 - 04/24/1999
Power Reactor
Event Number: 35629
Facility: MONTICELLO
Region: 3 State: MN
Unit: [1] [] []
RX Type: [1] GE-3
NRC Notified By: KEVIN PETERSON
HQ OPS Officer: FANGIE JONES
Region: 3 State: MN
Unit: [1] [] []
RX Type: [1] GE-3
NRC Notified By: KEVIN PETERSON
HQ OPS Officer: FANGIE JONES
Notification Date: 04/24/1999
Notification Time: 13:09 [ET]
Event Date: 04/24/1999
Event Time: 00:00 [CDT]
Last Update Date: 04/24/1999
Notification Time: 13:09 [ET]
Event Date: 04/24/1999
Event Time: 00:00 [CDT]
Last Update Date: 04/24/1999
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(2)(iii)(D) - ACCIDENT MITIGATION
10 CFR Section:
50.72(b)(2)(iii)(D) - ACCIDENT MITIGATION
Person (Organization):
MELVYN LEACH (R3)
MELVYN LEACH (R3)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 1 | N | N | 0 | Cold Shutdown | 0 | Cold Shutdown |
REACTOR WATER LEVEL HIGH ENOUGH TO ENTER THE MAIN STEAM LINES (Refer to event numbers 35617 and 35618 for event-related information.)
During an engineering evaluation of the reactor scram that occurred on 04/22/99, it was determined that reactor water level entered the main steam lines. This potentially made reactor core isolation cooling and high pressure coolant injection inoperable. The cause of the high water level condition is under investigation.
The licensee notified the NRC Resident Inspector and intends to notify state and local government agencies.
During an engineering evaluation of the reactor scram that occurred on 04/22/99, it was determined that reactor water level entered the main steam lines. This potentially made reactor core isolation cooling and high pressure coolant injection inoperable. The cause of the high water level condition is under investigation.
The licensee notified the NRC Resident Inspector and intends to notify state and local government agencies.
Power Reactor
Event Number: 35630
Facility: CLINTON
Region: 3 State: IL
Unit: [1] [] []
RX Type: [1] GE-6
NRC Notified By: JIM SCHOTTEL
HQ OPS Officer: FANGIE JONES
Region: 3 State: IL
Unit: [1] [] []
RX Type: [1] GE-6
NRC Notified By: JIM SCHOTTEL
HQ OPS Officer: FANGIE JONES
Notification Date: 04/24/1999
Notification Time: 15:28 [ET]
Event Date: 04/24/1999
Event Time: 14:30 [CDT]
Last Update Date: 04/26/1999
Notification Time: 15:28 [ET]
Event Date: 04/24/1999
Event Time: 14:30 [CDT]
Last Update Date: 04/26/1999
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(1)(v) - OTHER ASMT/COMM INOP
10 CFR Section:
50.72(b)(1)(v) - OTHER ASMT/COMM INOP
Person (Organization):
MELVYN LEACH (R3)
MELVYN LEACH (R3)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 1 | N | N | 0 | Cold Shutdown | 0 | Cold Shutdown |
SAFETY PARAMETER DISPLAY SYSTEM (SPDS) OUT OF SERVICE DUE TO MAINTENANCE.
Planned maintenance on uninterruptible power supply (UPS) bus (1B) for the process computer will disable some points on the SPDS for 48 hours. Operators are taking compensatory measures for monitoring parameters.
The licensee notified the NRC resident inspector.
******************** UPDATE AT 1910 ON 04/26/99 FROM RICH CHEAR TO TROCINE ********************
The following text is a portion of a facsimile received from the licensee:
"On 04/24/99, Clinton Power Station reported that plant [SPDS] was not available during the planned UPS 1B bus outage. During this time, the control room operators monitored other information sources for the information unavailable on SPDS."
"On 04/26/99, the UPS 1B bus [was] returned to service, and the SPDS [was] restored at 1720 [CDT]. The SPDS is now available and operational."
The licensee notified the NRC resident inspector. The NRC operations officer notified the R3DO (Madera).
Planned maintenance on uninterruptible power supply (UPS) bus (1B) for the process computer will disable some points on the SPDS for 48 hours. Operators are taking compensatory measures for monitoring parameters.
The licensee notified the NRC resident inspector.
******************** UPDATE AT 1910 ON 04/26/99 FROM RICH CHEAR TO TROCINE ********************
The following text is a portion of a facsimile received from the licensee:
"On 04/24/99, Clinton Power Station reported that plant [SPDS] was not available during the planned UPS 1B bus outage. During this time, the control room operators monitored other information sources for the information unavailable on SPDS."
"On 04/26/99, the UPS 1B bus [was] returned to service, and the SPDS [was] restored at 1720 [CDT]. The SPDS is now available and operational."
The licensee notified the NRC resident inspector. The NRC operations officer notified the R3DO (Madera).
Power Reactor
Event Number: 35631
Facility: BRAIDWOOD
Region: 3 State: IL
Unit: [] [2] []
RX Type: [1] W-4-LP,[2] W-4-LP
NRC Notified By: MARK ANDREWS
HQ OPS Officer: FANGIE JONES
Region: 3 State: IL
Unit: [] [2] []
RX Type: [1] W-4-LP,[2] W-4-LP
NRC Notified By: MARK ANDREWS
HQ OPS Officer: FANGIE JONES
Notification Date: 04/24/1999
Notification Time: 22:15 [ET]
Event Date: 04/24/1999
Event Time: 19:36 [CDT]
Last Update Date: 04/24/1999
Notification Time: 22:15 [ET]
Event Date: 04/24/1999
Event Time: 19:36 [CDT]
Last Update Date: 04/24/1999
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(2)(ii) - ESF ACTUATION
10 CFR Section:
50.72(b)(2)(ii) - ESF ACTUATION
Person (Organization):
MELVYN LEACH (R3)
MELVYN LEACH (R3)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 2 | N | N | 0 | Cold Shutdown | 0 | Cold Shutdown |
HIGH STEAM GENERATOR LEVEL ESF ACTUATION
During cooldown, after performing a plant shutdown for a refueling outage, narrow range level was noted to be increasing in the '2A' and '2C' steam generators. The feedwater isolation valves were checked closed, and additional manual isolation valves were closed. Steam generator blowdown was in the process of being put in service when level reached the P14 setpoint which caused an engineered safety features actuation (includes main feedwater pump trip and feedwater isolation signal).
Further investigation found auxiliary feedwater valves open that together with the pressure head from the water level in the condensate tank was sufficient to feed the steam generators.
Steam generator level was restored once blowdown was established.
The licensee notified the NRC Resident Inspector.
During cooldown, after performing a plant shutdown for a refueling outage, narrow range level was noted to be increasing in the '2A' and '2C' steam generators. The feedwater isolation valves were checked closed, and additional manual isolation valves were closed. Steam generator blowdown was in the process of being put in service when level reached the P14 setpoint which caused an engineered safety features actuation (includes main feedwater pump trip and feedwater isolation signal).
Further investigation found auxiliary feedwater valves open that together with the pressure head from the water level in the condensate tank was sufficient to feed the steam generators.
Steam generator level was restored once blowdown was established.
The licensee notified the NRC Resident Inspector.
Power Reactor
Event Number: 35627
Facility: NINE MILE POINT
Region: 1 State: NY
Unit: [] [2] []
RX Type: [1] GE-2,[2] GE-5
NRC Notified By: BRIAN WEAVER
HQ OPS Officer: JOHN MacKINNON
Region: 1 State: NY
Unit: [] [2] []
RX Type: [1] GE-2,[2] GE-5
NRC Notified By: BRIAN WEAVER
HQ OPS Officer: JOHN MacKINNON
Notification Date: 04/24/1999
Notification Time: 05:09 [ET]
Event Date: 04/24/1999
Event Time: 04:19 [EDT]
Last Update Date: 04/24/1999
Notification Time: 05:09 [ET]
Event Date: 04/24/1999
Event Time: 04:19 [EDT]
Last Update Date: 04/24/1999
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(1)(i)(A) - PLANT S/D REQD BY TS 50.72(b)(1)(iv) - ECCS INJECTION 50.72(b)(2)(ii) - ESF ACTUATION
10 CFR Section:
50.72(b)(1)(i)(A) - PLANT S/D REQD BY TS 50.72(b)(1)(iv) - ECCS INJECTION 50.72(b)(2)(ii) - ESF ACTUATION
Person (Organization):
MOHAMED SHANBAKY (R1)
WILLIAM BATEMAN (NRR)
JOSEPH GIITTER (IRO)
MOHAMED SHANBAKY (R1)
WILLIAM BATEMAN (NRR)
JOSEPH GIITTER (IRO)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 2 | A/R | Y | 100 | Power Operation | 0 | Hot Shutdown |
REACTOR SCRAM DUE TO UNKNOWN ELECTRICAL TRANSIENT
The reactor scrammed due to an unknown electrical transient. All control rods fully inserted into the core. Both electric-driven reactor feedwater pumps tripped, all three condensate booster pumps tripped, and the recirculation pumps tripped. The plant is in natural circulation with high pressure core spray (HPCS) system injecting and maintaining reactor vessel water level between 160 to 200 inches. (Normal reactor vessel water level is 184 inches, and the top of the active fuel is -18 inches.) Reactor core isolation cooling (RCIC) and HPCS received automatic initiation signals on Level 2, and the Division 3 diesel automatically started but did not load. The RCIC pump failed to come up to speed and has been tripped. The main steam isolation valves are open, and reactor vessel pressure is being maintained at 600 to 700 psig. Uninterruptible power supply (UPS) "3B" tripped and has a blown fuse which prevents resetting of the inboard containment isolation valves. Both Containment Monitoring System(CMS) cabinets 10A and 10B are isolated (leak detection for particulate and gaseous) causing entry into Technical Specification 3.0.3. Due to UPS "3B" being tripped, the licensee has a one-half isolation signal to the main steam isolation valves. UPS "3B" provides logic to the scram system, etc. (UPS "3B" is essentially a major logic power supply for UPS.)
The electrical transient (not sure if the transient was caused from offsite power loss) caused a partial loss of lighting in the control room, a complete loss of lighting to the turbine building (was reported), and a loss of site perimeter lighting for a very short period of time. All UPS went to a battery source of power for a short period of time and then transferred back to normal power source (normally happens on a big electrical transient). All electrical in-house buses powered up, and the plant is stable. A condensate booster pump has been reestablished, and the licensee is starting to investigate what caused the electrical transient, RCIC not coming up to speed (places them in Tech Spec 3.7.4), and what caused the fuse to blow to UPS "3B."
The licensee had not, at the time of this call, checked with Unit 1 to see if it had experienced a power loss for a short period of time.
The NRC resident inspector will be notified of this event by the licensee.
***UPDATE AT 0751 EDT FROM ROY GREEN TAKEN BY MACKINNON***
The licensee updated this event to add the 4-hour notifications under 10 CFR 50.72 (b)(2) for a reactor protection system actuation, engineered safety feature (ESF) actuations, and accident mitigation. The 4-hour notifications were required for the reactor scram and the following ESF actuations: reactor water cleanup system isolation, standby gas initiation, control room special filter train initiation, reactor vessel water Level 2 containment isolations, and Division 3 (HPCS) automatic start on HPCS initiation. The third 4-hour notification was required for accident mitigation due to single train RCIC failure upon initiation.
Plant Status:
The scram has been reset, normal cooldown is in progress via the turbine bypass valves, reactor vessel water level is being maintained in its normal band with normal feedwater system, and UPS-3B remains de-energized preventing containment isolation recovery. Troubleshooting is in progress on UPS-3B and RCIC. (The region of instability on the power to flow map was not entered.)
The licensee plans to place the unit in a Cold Shutdown condition on natural circulation.
The NRC resident inspector was notified of this update by the licensee. The R1DO ( Mohamed Shanbaky) was notified by the NRC operations officer.
The reactor scrammed due to an unknown electrical transient. All control rods fully inserted into the core. Both electric-driven reactor feedwater pumps tripped, all three condensate booster pumps tripped, and the recirculation pumps tripped. The plant is in natural circulation with high pressure core spray (HPCS) system injecting and maintaining reactor vessel water level between 160 to 200 inches. (Normal reactor vessel water level is 184 inches, and the top of the active fuel is -18 inches.) Reactor core isolation cooling (RCIC) and HPCS received automatic initiation signals on Level 2, and the Division 3 diesel automatically started but did not load. The RCIC pump failed to come up to speed and has been tripped. The main steam isolation valves are open, and reactor vessel pressure is being maintained at 600 to 700 psig. Uninterruptible power supply (UPS) "3B" tripped and has a blown fuse which prevents resetting of the inboard containment isolation valves. Both Containment Monitoring System(CMS) cabinets 10A and 10B are isolated (leak detection for particulate and gaseous) causing entry into Technical Specification 3.0.3. Due to UPS "3B" being tripped, the licensee has a one-half isolation signal to the main steam isolation valves. UPS "3B" provides logic to the scram system, etc. (UPS "3B" is essentially a major logic power supply for UPS.)
The electrical transient (not sure if the transient was caused from offsite power loss) caused a partial loss of lighting in the control room, a complete loss of lighting to the turbine building (was reported), and a loss of site perimeter lighting for a very short period of time. All UPS went to a battery source of power for a short period of time and then transferred back to normal power source (normally happens on a big electrical transient). All electrical in-house buses powered up, and the plant is stable. A condensate booster pump has been reestablished, and the licensee is starting to investigate what caused the electrical transient, RCIC not coming up to speed (places them in Tech Spec 3.7.4), and what caused the fuse to blow to UPS "3B."
The licensee had not, at the time of this call, checked with Unit 1 to see if it had experienced a power loss for a short period of time.
The NRC resident inspector will be notified of this event by the licensee.
***UPDATE AT 0751 EDT FROM ROY GREEN TAKEN BY MACKINNON***
The licensee updated this event to add the 4-hour notifications under 10 CFR 50.72 (b)(2) for a reactor protection system actuation, engineered safety feature (ESF) actuations, and accident mitigation. The 4-hour notifications were required for the reactor scram and the following ESF actuations: reactor water cleanup system isolation, standby gas initiation, control room special filter train initiation, reactor vessel water Level 2 containment isolations, and Division 3 (HPCS) automatic start on HPCS initiation. The third 4-hour notification was required for accident mitigation due to single train RCIC failure upon initiation.
Plant Status:
The scram has been reset, normal cooldown is in progress via the turbine bypass valves, reactor vessel water level is being maintained in its normal band with normal feedwater system, and UPS-3B remains de-energized preventing containment isolation recovery. Troubleshooting is in progress on UPS-3B and RCIC. (The region of instability on the power to flow map was not entered.)
The licensee plans to place the unit in a Cold Shutdown condition on natural circulation.
The NRC resident inspector was notified of this update by the licensee. The R1DO ( Mohamed Shanbaky) was notified by the NRC operations officer.