Event Notification Report for August 22, 2002
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
08/21/2002 - 08/22/2002
Power Reactor
Event Number: 39144
Facility: MILLSTONE
Region: 1 State: CT
Unit: [] [] [3]
RX Type: [1] GE-3,[2] CE,[3] W-4-LP
NRC Notified By: MICHAEL MARTELL
HQ OPS Officer: FANGIE JONES
Region: 1 State: CT
Unit: [] [] [3]
RX Type: [1] GE-3,[2] CE,[3] W-4-LP
NRC Notified By: MICHAEL MARTELL
HQ OPS Officer: FANGIE JONES
Notification Date: 08/22/2002
Notification Time: 17:06 [ET]
Event Date: 08/22/2002
Event Time: 16:33 [EDT]
Last Update Date: 08/23/2002
Notification Time: 17:06 [ET]
Event Date: 08/22/2002
Event Time: 16:33 [EDT]
Last Update Date: 08/23/2002
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(3)(ii)(B) - UNANALYZED CONDITION
10 CFR Section:
50.72(b)(3)(ii)(B) - UNANALYZED CONDITION
Person (Organization):
CLIFFORD ANDERSON (R1)
CLIFFORD ANDERSON (R1)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 3 | N | Y | 95 | Power Operation | 95 | Power Operation |
UNANALYZED CONDITION CONCERNING STEAM GENERATOR ATMOSPHERIC RELIEF VALVE BYPASS VALVES
Historical analysis deficiencies associated with the steam generator atmospheric dump bypass valves, a condition that during a fire could cause seriously degrade the safety of the plant.
"The system affected is main steam, there are no actuation signals. The cause is historical analysis deficiencies. There are no affects on the plant. There are no actions taken or planned at this time and there is no additional information. The NRC Resident Inspector was notified. The State and Local Authorities have been notified."
* * * UPDATE 1605EDT ON 8/23/02 FROM MICHAEL MARTELL TO S. SANDIN * * *
The following information from Millstone Condition Report CR-02-08666 was provided by the licensee as an update:
"On August 22, 2002, with Millstone Unit 3 in Mode 1, and as a result of transient analysis of the fire shutdown scenarios, the potential for spurious operation associated with the Main Steam atmospheric dump valve bypass motor operated valves (3MS*MOV74A thru D) from a hot short was found to result in non-compliance with the BTP 9.5-1 performance criteria. The Millstone Unit 3 licensing basis regarding BTP 9.5-1 performance criteria provides that a fire in an alternate shutdown area shall pose a transient no more severe than a reactor trip due to loss of normal power and that pressurizer level remain in the indicating range. Spurious operation of plant components due to credible hot shorts must be postulated and have methods for mitigation that do not require the use of any other component potentially affected by the fire. The current BTP 9.5-1 compliance report and shutdown methods address the spurious opening of the Main Steam atmospheric dump valve bypass motor operated valves. Fire safe shutdown procedures provide methods for mitigating this spurious actuation.
"On-going effort to validate assumptions used in the fire safe shutdown analysis concluded that insufficient operator response time was available to support mitigation of this transient. It has been determined that spurious opening of one of the dump valves could cause pressurizer level to go below the indicating range in a time frame shorter than originally assumed. This condition is being reported as an unanalyzed condition that significantly degrades plant safety, pursuant to 50.72 (b)(3)(ii)(B).
"It should be noted that, consistent with the Licensing Basis, this analysis assumes a fire of sufficient magnitude to result in an instantaneous hot short. Such fires are viewed to be very low probability events. The fire areas of concern are the control room and cable spreading area. The control room is continuously manned, and currently a continuous compensatory fire watch is required in the cable spreading room for other conditions. No additional compensatory actions are judged to be necessary at this time. Corrective actions are under evaluation in accordance with the Millstone corrective action program."
The licensee informed the NRC Resident Inspector. Notified R1DO(Noggle).
Historical analysis deficiencies associated with the steam generator atmospheric dump bypass valves, a condition that during a fire could cause seriously degrade the safety of the plant.
"The system affected is main steam, there are no actuation signals. The cause is historical analysis deficiencies. There are no affects on the plant. There are no actions taken or planned at this time and there is no additional information. The NRC Resident Inspector was notified. The State and Local Authorities have been notified."
* * * UPDATE 1605EDT ON 8/23/02 FROM MICHAEL MARTELL TO S. SANDIN * * *
The following information from Millstone Condition Report CR-02-08666 was provided by the licensee as an update:
"On August 22, 2002, with Millstone Unit 3 in Mode 1, and as a result of transient analysis of the fire shutdown scenarios, the potential for spurious operation associated with the Main Steam atmospheric dump valve bypass motor operated valves (3MS*MOV74A thru D) from a hot short was found to result in non-compliance with the BTP 9.5-1 performance criteria. The Millstone Unit 3 licensing basis regarding BTP 9.5-1 performance criteria provides that a fire in an alternate shutdown area shall pose a transient no more severe than a reactor trip due to loss of normal power and that pressurizer level remain in the indicating range. Spurious operation of plant components due to credible hot shorts must be postulated and have methods for mitigation that do not require the use of any other component potentially affected by the fire. The current BTP 9.5-1 compliance report and shutdown methods address the spurious opening of the Main Steam atmospheric dump valve bypass motor operated valves. Fire safe shutdown procedures provide methods for mitigating this spurious actuation.
"On-going effort to validate assumptions used in the fire safe shutdown analysis concluded that insufficient operator response time was available to support mitigation of this transient. It has been determined that spurious opening of one of the dump valves could cause pressurizer level to go below the indicating range in a time frame shorter than originally assumed. This condition is being reported as an unanalyzed condition that significantly degrades plant safety, pursuant to 50.72 (b)(3)(ii)(B).
"It should be noted that, consistent with the Licensing Basis, this analysis assumes a fire of sufficient magnitude to result in an instantaneous hot short. Such fires are viewed to be very low probability events. The fire areas of concern are the control room and cable spreading area. The control room is continuously manned, and currently a continuous compensatory fire watch is required in the cable spreading room for other conditions. No additional compensatory actions are judged to be necessary at this time. Corrective actions are under evaluation in accordance with the Millstone corrective action program."
The licensee informed the NRC Resident Inspector. Notified R1DO(Noggle).
Power Reactor
Event Number: 39145
Facility: MCGUIRE
Region: 2 State: NC
Unit: [] [2] []
RX Type: [1] W-4-LP,[2] W-4-LP
NRC Notified By: DENNIS MOORE
HQ OPS Officer: STEVE SANDIN
Region: 2 State: NC
Unit: [] [2] []
RX Type: [1] W-4-LP,[2] W-4-LP
NRC Notified By: DENNIS MOORE
HQ OPS Officer: STEVE SANDIN
Notification Date: 08/22/2002
Notification Time: 17:25 [ET]
Event Date: 08/22/2002
Event Time: 16:50 [EDT]
Last Update Date: 08/22/2002
Notification Time: 17:25 [ET]
Event Date: 08/22/2002
Event Time: 16:50 [EDT]
Last Update Date: 08/22/2002
Emergency Class: UNUSUAL EVENT
10 CFR Section:
50.72(a) (1) (i) - EMERGENCY DECLARED 50.72(b)(2)(xi) - OFFSITE NOTIFICATION 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)(xi) - OFFSITE NOTIFICATION 50.72(b)(2)(iv)(B) - RPS ACTUATION - CRITICAL 50.72(b)(3)(iv)(A) - VALID SPECIF SYS ACTUATION
Person (Organization):
KEN BARR (R2)
JOHN HANNON (NRR)
JOSEPH HOLONICH (IRO)
KEN CIBOCH (FEMA)
KEN BARR (R2)
JOHN HANNON (NRR)
JOSEPH HOLONICH (IRO)
KEN CIBOCH (FEMA)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 2 | M/R | Y | 100 | Power Operation | 0 | Hot Standby |
UNIT 2 DECLARED AN UNUSUAL EVENT DUE TO A FIRE IN THE TURBINE BUILDING
"Fire in Turbine Building at H2 Dryer lasting for greater than 15 minutes. Fire out at 1655 [hours]. Fire reported at 1633 [hours]."
The Fire Brigade responded and extinguished the fire. The Hydrogen Dryer has been isolated. Offsite assistance was not requested. There were no injuries reported. A preliminary assessment revealed extensive damage to the Hydrogen Dryer as a result of the fire. The cause of the fire is under investigation. There were no maintenance activities, e.g., welding, in progress at the time.
Operators manually tripped Unit 2. All rods fully inserted. The plant responded as expected. No secondary reliefs lifted. Auxiliary Feedwater autostarted to maintain Steam Generator water levels. The Main Condenser is in-service removing decay heat via the main steam dumps. Cooldown limits were not exceeded during the transient. Unit 2 will remain in mode 3 pending completion of the investigation.
The licensee informed state/local agencies and the NRC Resident Inspector.
* * * UPDATED AT 1855 EDT ON 8/22/02 BY DENNIS MOORE TO FANGIE JONES * * *
Unusual Event terminated at 1830 EDT. The fire extinguished when the hydrogen isolation valve was closed, automatic sprinkler system actuated which allowed personnel access to the isolation valve.
The licensee notified the NRC Resident Inspector. Notified the R2DO (Ken Barr), NRR EO (John Hannon), IRO (Joe Holonich), and FEMA (David Barden).
* * * UPDATED AT 2023EDT ON 8/22/02 BY WAYNE HOYLE TO S. SANDIN * * *
The licensee furnished the following additional information:
"On August 22, 2002 at 1636 hours, a manual reactor trip was initiated on McGuire Unit 2 in response to a fire in a hydrogen dryer in the hydrogen supply to the Unit 2 Turbine Generator. As a result of the fire, the hydrogen supply to the turbine generator experienced a low pressure condition and plant operators manually tripped the reactor (RPS Actuation) to prevent damage to the turbine generator. Following the trip, the Unit 2 Auxiliary Feedwater Pumps started due to loss of Unit 2 Main Feedwater Pumps (Auxiliary Feedwater System Actuation). Subsequent to the start of the Unit 2 Auxiliary Feedwater Pumps, the 2C Steam Generator experienced a HI-HI water level. Level was restored and the water level in all four Steam Generators is currently in the normal band for existing plant conditions.
"The fire in the Unit 2 hydrogen dryer has been extinguished. Plant equipment necessary to safely shutdown Unit 2 operated correctly and the Unit is stable and in Mode 3. The Unit 2 Auxiliary Feedwater Pumps are still running supplying the Steam Generators. An investigation into the cause of the fire is in progress.
"The NRC Resident Inspector has been notified."
Notified R2DO(Barr).
"Fire in Turbine Building at H2 Dryer lasting for greater than 15 minutes. Fire out at 1655 [hours]. Fire reported at 1633 [hours]."
The Fire Brigade responded and extinguished the fire. The Hydrogen Dryer has been isolated. Offsite assistance was not requested. There were no injuries reported. A preliminary assessment revealed extensive damage to the Hydrogen Dryer as a result of the fire. The cause of the fire is under investigation. There were no maintenance activities, e.g., welding, in progress at the time.
Operators manually tripped Unit 2. All rods fully inserted. The plant responded as expected. No secondary reliefs lifted. Auxiliary Feedwater autostarted to maintain Steam Generator water levels. The Main Condenser is in-service removing decay heat via the main steam dumps. Cooldown limits were not exceeded during the transient. Unit 2 will remain in mode 3 pending completion of the investigation.
The licensee informed state/local agencies and the NRC Resident Inspector.
* * * UPDATED AT 1855 EDT ON 8/22/02 BY DENNIS MOORE TO FANGIE JONES * * *
Unusual Event terminated at 1830 EDT. The fire extinguished when the hydrogen isolation valve was closed, automatic sprinkler system actuated which allowed personnel access to the isolation valve.
The licensee notified the NRC Resident Inspector. Notified the R2DO (Ken Barr), NRR EO (John Hannon), IRO (Joe Holonich), and FEMA (David Barden).
* * * UPDATED AT 2023EDT ON 8/22/02 BY WAYNE HOYLE TO S. SANDIN * * *
The licensee furnished the following additional information:
"On August 22, 2002 at 1636 hours, a manual reactor trip was initiated on McGuire Unit 2 in response to a fire in a hydrogen dryer in the hydrogen supply to the Unit 2 Turbine Generator. As a result of the fire, the hydrogen supply to the turbine generator experienced a low pressure condition and plant operators manually tripped the reactor (RPS Actuation) to prevent damage to the turbine generator. Following the trip, the Unit 2 Auxiliary Feedwater Pumps started due to loss of Unit 2 Main Feedwater Pumps (Auxiliary Feedwater System Actuation). Subsequent to the start of the Unit 2 Auxiliary Feedwater Pumps, the 2C Steam Generator experienced a HI-HI water level. Level was restored and the water level in all four Steam Generators is currently in the normal band for existing plant conditions.
"The fire in the Unit 2 hydrogen dryer has been extinguished. Plant equipment necessary to safely shutdown Unit 2 operated correctly and the Unit is stable and in Mode 3. The Unit 2 Auxiliary Feedwater Pumps are still running supplying the Steam Generators. An investigation into the cause of the fire is in progress.
"The NRC Resident Inspector has been notified."
Notified R2DO(Barr).