Event Notification Report for May 26, 2017
U.S. Nuclear Regulatory Commission
Operations Center
EVENT REPORTS FOR
05/25/2017 - 05/26/2017
EVENT NUMBERS
52771
Power Reactor
Event Number: 52771
Facility: COOPER
Region: 4 State: NE
Unit: [1] [] []
RX Type: [1] GE-4
NRC Notified By: RANDY KOUBA
HQ OPS Officer: HOWIE CROUCH
Region: 4 State: NE
Unit: [1] [] []
RX Type: [1] GE-4
NRC Notified By: RANDY KOUBA
HQ OPS Officer: HOWIE CROUCH
Notification Date: 05/26/2017
Notification Time: 12:11 [ET]
Event Date: 05/26/2017
Event Time: 03:21 [CDT]
Last Update Date: 05/26/2017
Notification Time: 12:11 [ET]
Event Date: 05/26/2017
Event Time: 03:21 [CDT]
Last Update Date: 05/26/2017
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(3)(v)(D) - ACCIDENT MITIGATION
10 CFR Section:
50.72(b)(3)(v)(D) - ACCIDENT MITIGATION
Person (Organization):
JEREMY GROOM (R4DO)
JEREMY GROOM (R4DO)
| 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
"On May 26, 2017 at 0321 [CDT], Control Room staff questioned air flow and differential pressure in the Main Control Room. The CREFS [control room emergency filtration system] booster fan discharges to the Control Room supply fan suctions. With supply fan flows questionable, reasonable assurance that CREFS would fulfill its safety function could not be established. Engineering confirmed CREFS system flow rate by testing and determined the actual flow was 802 cfm, below the required flow of 810 cfm. Based on this information, CREFS was declared inoperable.
"CREFS is a single train system. Per 10CFR50.72(b)(3)(v)(D), an 8-hour report is required due to the fact that, at the time of discovery, this condition could have prevented the fulfillment of the safety function of an SSC that is required to mitigate the consequences of an accident.
"The NRC Senior Resident Inspector will be informed."
CREFS being out of service places the plant in a 7-day LCO shutdown action statement.
"On May 26, 2017 at 0321 [CDT], Control Room staff questioned air flow and differential pressure in the Main Control Room. The CREFS [control room emergency filtration system] booster fan discharges to the Control Room supply fan suctions. With supply fan flows questionable, reasonable assurance that CREFS would fulfill its safety function could not be established. Engineering confirmed CREFS system flow rate by testing and determined the actual flow was 802 cfm, below the required flow of 810 cfm. Based on this information, CREFS was declared inoperable.
"CREFS is a single train system. Per 10CFR50.72(b)(3)(v)(D), an 8-hour report is required due to the fact that, at the time of discovery, this condition could have prevented the fulfillment of the safety function of an SSC that is required to mitigate the consequences of an accident.
"The NRC Senior Resident Inspector will be informed."
CREFS being out of service places the plant in a 7-day LCO shutdown action statement.