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Event Notification Report for July 18, 2006

U.S. Nuclear Regulatory Commission
Operations Center

Event Reports For
07/17/2006 - 07/18/2006

** EVENT NUMBERS **


42711 42712

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Power Reactor Event Number: 42711
Facility: COOPER
Region: 4 State: NE
Unit: [1] [ ] [ ]
RX Type: [1] GE-4
NRC Notified By: ANDREW OHRABLO
HQ OPS Officer: PETE SNYDER
Notification Date: 07/17/2006
Notification Time: 21:38 [ET]
Event Date: 07/17/2006
Event Time: 15:47 [CDT]
Last Update Date: 07/17/2006
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(3)(v)(D) - ACCIDENT MITIGATION
Person (Organization):
VIVIAN CAMPBELL (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

Event Text

CONTROL ROOM VENTILATION FLOW BELOW LIMITS

"During review of instrumentation calibration, it was determined that a faulty flow instrument was used for determination of CREFS (Control Room Emergency Filtration System) flow. Due to the error of the flow instrumentation previous test results were deemed to be high outside acceptance criteria. These tests were performed in October of 2005. The CREFS was declared inoperable and preparation was made to rerun the surveillance. At 1900 the surveillance was completed. The results of the surveillance determined that CREFS flow was below the allowable limit. The minimum flow for CREFS is a requirement for post DBA dose calculation for Control Room personnel. With minimum flow not maintained, the Control Room post accident dose calculations may be violated.

"CREFS remains inoperable pending adjustments of ventilation dampers and successful performance of surveillance testing.

"Resident inspector has been notified."

The licensee has entered Technical Specification LCO 3.7.4, Condition A, which is a 7 day LCO.

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Power Reactor Event Number: 42712
Facility: BYRON
Region: 3 State: IL
Unit: [1] [2] [ ]
RX Type: [1] W-4-LP,[2] W-4-LP
NRC Notified By: KELLY FERNEAU
HQ OPS Officer: MIKE RIPLEY
Notification Date: 07/17/2006
Notification Time: 23:56 [ET]
Event Date: 07/17/2006
Event Time: 21:46 [CDT]
Last Update Date: 07/18/2006
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(3)(xiii) - LOSS COMM/ASMT/RESPONSE
Person (Organization):
JAMNES CAMERON (R3)

Unit SCRAM Code RX CRIT Initial PWR Initial RX Mode Current PWR Current RX Mode
1 N Y 100 Power Operation 100 Power Operation
2 N Y 100 Power Operation 100 Power Operation

Event Text

EMERGENCY EVACUATION SIREN FAILURES DUE TO THUNDERSTORMS

"Greater than 25% of the emergency sirens have failed due to a severe thunderstorm in the area."

The licensee stated that 30 sirens had failed and that restoration activities were currently in progress. The licensee will notify the NRC Resident Inspector.

* * * UPDATE FROM J. KOEPLIN TO M. RIPLEY 0503 ET 07/18/06 * * *

As of 2317 CDT 07/18/06, the number of inoperable sirens fell below 25% of all sirens with 23 failed sirens not restored to service. Restoration activities remain in progress. The licensee will notify the NRC Resident Inspector.

Notified R3 DO (Cameron)

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Friday, March 30, 2012