Event Notification Report for January 21, 2001
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
01/20/2001 - 01/21/2001
EVENT NUMBERS
37673
!!!!! THIS EVENT HAS BEEN RETRACTED !!!!!
!!!!! THIS EVENT HAS BEEN RETRACTED !!!!!
Power Reactor
Event Number: 37673
Facility: COOPER
Region: 4 State: NE
Unit: [1] [] []
RX Type: [1] GE-4
NRC Notified By: WILLIAM GREEN
HQ OPS Officer: DOUG WEAVER
Region: 4 State: NE
Unit: [1] [] []
RX Type: [1] GE-4
NRC Notified By: WILLIAM GREEN
HQ OPS Officer: DOUG WEAVER
Notification Date: 01/21/2001
Notification Time: 18:29 [ET]
Event Date: 01/21/2001
Event Time: 15:28 [CST]
Last Update Date: 03/01/2001
Notification Time: 18:29 [ET]
Event Date: 01/21/2001
Event Time: 15:28 [CST]
Last Update Date: 03/01/2001
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):
KRISS KENNEDY (R4)
KRISS KENNEDY (R4)
| Unit | SCRAM Code | RX Crit | Initial PWR | Initial RX Mode | Current PWR | Current RX Mode |
|---|---|---|---|---|---|---|
| 1 | N | Y | 100 | Power Operation | 100 | Power Operation |
CONTROL ROOM EMERGENCY FILTRATION SYSTEM INOPERABLE
At 1528 the Control Room Emergency Filtration System (CREFS) was declared inoperable when fire door H305 was noted to hang open instead of fully closing when personnel passed through the door. BLDG-DOOR-H305 is a Control Room Envelope Door. CREFS is a single train system. When CREFS was determined to be inoperable Technical Specification LCO 3.7.4 condition A was entered. This LCO requires the restoration of CREFS to OPERABLE status within 7 days or be in MODE 3 within 12 hours and MODE 4 within 36 hours.
Following the transfer of CREFS to DIV 1 power at 13:30, it was subsequently noted that the control room blast doors seemed harder to open than normal. The ventilation lineup for the Control Building was verified to be correct. During this verification it was determined that BLDG-DOOR-H305 would not operate properly and the door and CREFS were declared inoperable.
Ventilation flow through other Control Room Boundary Doors appears [to]be abnormal for the present ventilation lineup. A Fire Watch has been stationed at BLDG-DOOR-H305. A Problem Identification Report has been initiated to identify that BLDG-DOOR-H305 will not close by itself from the fully open position. The ventilation lineup has not been changed since the discovery of this condition for evidence preservation. The Ventilation System Engineer is responding to the Site to assist with troubleshooting of the ventilation system.
The licensee notified the NRC resident inspector.
* * * UPDATE 1514EST ON 3/1/01 FROM DAVID VANDERKAMP TO S. SANDIN * * *
The licensee is retracting this report based on the following:
"Basis for Retraction:
"Event Number 37673 reported a condition at Cooper Nuclear Station (CNS) where the Control Room Emergency Filtration System (CREFS) was declared inoperable. This was a result of the control room envelope boundary being declared inoperable due to a fire door not closing automatically when it was opened raising questions about integrity of the envelope.
"On a specific occasion, a fire door that allows access from the control room access hall to the computer room, was unable to close without assistance. This was discovered when an operator passed through the door and it failed to close behind him. He had to manually assist the door closed. The door was declared inoperable as a fire boundary door and a fire watch was posted. Since the door forms part of the control room envelope boundary, that boundary was also declared inoperable due to concerns about the envelope integrity. Therefore, CREFS was declared inoperable.
"Technical Specifications require that the control room envelope be maintained at a positive pressure in the emergency line-up on the control room ventilation system but not in the normal line-up. This should be considered a normal operation of the door for entry and exit per Technical Specification Bases 3.7.4. This states that:
'...in addition, the control room boundary must be maintained, including the integrity of the walls, floors, ceilings, ductwork and access doors, such that the pressurization limit of SR 3.7.4.4 can be met. However, it is acceptable for access doors to be open for normal control room entry and exit, and not consider it to be a failure to meet the LCO.'
"There was no condition present that would challenge the integrity of the Control Room envelope, other than the door not closing automatically. The door was manually closed while being used for access. Signs are posted at doors that should be closed to ensure that doors are closed after they are opened. The operator passing through this door closed the door when it would not close by itself. Not withstanding the fact that the door was
closed as required; a Fire Watch was posted to better ensure that the door was properly closed until the reason for it's not automatically closing was determined. No major components failed.
"The cause of the door not automatically closing was determined to be a mis-positioned, manually operated damper. The mis-positioned damper caused a decreased positive pressure inside the Control Room envelope boundary impacting the automatic door closure. If an accident had occurred while this damper was mis-positioned, the Control Room Emergency Filtration System would have performed its safety function as designed and continued to be operable.
"Based on this updated information, the District has determined that this event is not reportable under the requirements of 10CFR50.72(b)(2)(iii)(D), and as such, event 37673 is retracted."
The licensee will inform the NRC resident inspector. Notified R4DO(Howell).
At 1528 the Control Room Emergency Filtration System (CREFS) was declared inoperable when fire door H305 was noted to hang open instead of fully closing when personnel passed through the door. BLDG-DOOR-H305 is a Control Room Envelope Door. CREFS is a single train system. When CREFS was determined to be inoperable Technical Specification LCO 3.7.4 condition A was entered. This LCO requires the restoration of CREFS to OPERABLE status within 7 days or be in MODE 3 within 12 hours and MODE 4 within 36 hours.
Following the transfer of CREFS to DIV 1 power at 13:30, it was subsequently noted that the control room blast doors seemed harder to open than normal. The ventilation lineup for the Control Building was verified to be correct. During this verification it was determined that BLDG-DOOR-H305 would not operate properly and the door and CREFS were declared inoperable.
Ventilation flow through other Control Room Boundary Doors appears [to]be abnormal for the present ventilation lineup. A Fire Watch has been stationed at BLDG-DOOR-H305. A Problem Identification Report has been initiated to identify that BLDG-DOOR-H305 will not close by itself from the fully open position. The ventilation lineup has not been changed since the discovery of this condition for evidence preservation. The Ventilation System Engineer is responding to the Site to assist with troubleshooting of the ventilation system.
The licensee notified the NRC resident inspector.
* * * UPDATE 1514EST ON 3/1/01 FROM DAVID VANDERKAMP TO S. SANDIN * * *
The licensee is retracting this report based on the following:
"Basis for Retraction:
"Event Number 37673 reported a condition at Cooper Nuclear Station (CNS) where the Control Room Emergency Filtration System (CREFS) was declared inoperable. This was a result of the control room envelope boundary being declared inoperable due to a fire door not closing automatically when it was opened raising questions about integrity of the envelope.
"On a specific occasion, a fire door that allows access from the control room access hall to the computer room, was unable to close without assistance. This was discovered when an operator passed through the door and it failed to close behind him. He had to manually assist the door closed. The door was declared inoperable as a fire boundary door and a fire watch was posted. Since the door forms part of the control room envelope boundary, that boundary was also declared inoperable due to concerns about the envelope integrity. Therefore, CREFS was declared inoperable.
"Technical Specifications require that the control room envelope be maintained at a positive pressure in the emergency line-up on the control room ventilation system but not in the normal line-up. This should be considered a normal operation of the door for entry and exit per Technical Specification Bases 3.7.4. This states that:
'...in addition, the control room boundary must be maintained, including the integrity of the walls, floors, ceilings, ductwork and access doors, such that the pressurization limit of SR 3.7.4.4 can be met. However, it is acceptable for access doors to be open for normal control room entry and exit, and not consider it to be a failure to meet the LCO.'
"There was no condition present that would challenge the integrity of the Control Room envelope, other than the door not closing automatically. The door was manually closed while being used for access. Signs are posted at doors that should be closed to ensure that doors are closed after they are opened. The operator passing through this door closed the door when it would not close by itself. Not withstanding the fact that the door was
closed as required; a Fire Watch was posted to better ensure that the door was properly closed until the reason for it's not automatically closing was determined. No major components failed.
"The cause of the door not automatically closing was determined to be a mis-positioned, manually operated damper. The mis-positioned damper caused a decreased positive pressure inside the Control Room envelope boundary impacting the automatic door closure. If an accident had occurred while this damper was mis-positioned, the Control Room Emergency Filtration System would have performed its safety function as designed and continued to be operable.
"Based on this updated information, the District has determined that this event is not reportable under the requirements of 10CFR50.72(b)(2)(iii)(D), and as such, event 37673 is retracted."
The licensee will inform the NRC resident inspector. Notified R4DO(Howell).