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Event Notification Report for December 22, 2006

U.S. Nuclear Regulatory Commission
Operations Center

Event Reports For
12/21/2006 - 12/22/2006

** EVENT NUMBERS **


41755 43059 43060

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Power Reactor Event Number: 41755
Facility: SUMMER
Region: 2 State: SC
Unit: [1] [ ] [ ]
RX Type: [1] W-3-LP
NRC Notified By: STEVEN WEBSTER
HQ OPS Officer: BILL HUFFMAN
Notification Date: 06/08/2005
Notification Time: 02:48 [ET]
Event Date: 06/07/2005
Event Time: 20:20 [EDT]
Last Update Date: 12/22/2006
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(3)(xiii) - LOSS COMM/ASMT/RESPONSE
Person (Organization):
KERRY LANDIS (R2)

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

TWENTY-EIGHT EARLY WARNING SIRENS TEMPORARILY INOPERABLE

"On June 7th 2005 at 20:00 hours our EWSS System performed an automated poll of active Early Warning Sirens. Normally this action is completed in 15 to 20 minutes. This polling indicated not all sirens had responded to the automated signal. Emergency planning department personnel were notified and called to site to determine system status. Their attempts to manually poll the active sirens determined that twenty eight (28) sirens were not responding. Our EWSS system consists of one hundred six (106) sirens. A loss of twenty eight (28) sirens left our system at seventy three percent (73%) of its capacity. South Carolina state and the four (4) local counties were notified of the systems condition within one hour as required by our Nuclear Licensing procedure (NL-122). This same procedure requires an eight (8) hour telephone notification to the Nuclear Regulatory Commission. This requirement is based on 10CFR50.72(b)(3)(xiii).

"At 00:15 hours June 8th 2005 our communications department located the faulty siren and disabled its radio transponder, this action restored the other twenty seven (27) sirens to service. This restoration was verified by performing a manual poll of active sirens. The South Carolina state and local counties were notified of system restoration.

"During the evening hours of June 7th 2005 a thunder storm passed through the station's ten (10) mile emergency planning zone. One siren, Fairfield fifty two (F-52) had apparently been struck by lightning and caused its radio transponder to go into a continuous transmit mode. This errant radio signal blocked the polling signal from the other twenty seven (27) sirens. Based on communications department report had the EWSS system been actuated those twenty eight (28) sirens would not have sounded as required."

The licensee has notified State and local authorities as well as the NRC Resident Inspector.

* * * UPDATE FROM SUSAN REESE TO JOE O'HARA ON 12/21/06 AT 1013 * * *

"On June 7th 2005 at 20:00 hours our EWSS System performed an automated poll of active Early Warning Sirens. Normally this action is completed in 15 to 20 minutes. This polling indicated not all sirens had responded to the automated signal. Emergency planning department personnel were notified and called to site to determine system status. Their attempts to manually poll the active sirens determined that twenty eight (28) sirens were not responding. Our EWSS system consists of one hundred six (106) sirens. A loss of twenty eight (28) sirens left our system at seventy three percent (73%) of its capacity. South Carolina state and the four (4) local counties were notified of the systems condition within one hour as required by our Nuclear Licensing procedure (NL-122). This same procedure requires an eight (8) hour telephone notification to the Nuclear Regulatory Commission. This requirement is based on 10CFR50.72(b)(3)(xiii).

"At 00:15 hours June 8th 2005 our communications department located the faulty siren and disabled its radio transponder, this action restored the other twenty seven (27) sirens to service. This restoration was verified by performing a manual poll of active sirens. The South Carolina state and local counties were notified of system restoration.

"During the evening hours of June 7th 2005 a thunder storm passed through the station's ten (10) mile emergency planning zone. One siren, Fairfield fifty two (F-52) had apparently been struck by lightning and caused its radio transponder to go into a continuous transmit mode. This errant radio signal blocked the polling signal from the other twenty seven (27) sirens. Based on the licensee's Communications Department Report, if the EWSS had been actuated, all sirens, except the faulty siren struck by lightning would have activated. However, the siren feedback system may not have been able to determine if all sirens activated."

The licensee notified the NRC Resident Inspector.

Notified R2DO (Munday)

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Power Reactor Event Number: 43059
Facility: MILLSTONE
Region: 1 State: CT
Unit: [ ] [2] [ ]
RX Type: [1] GE-3,[2] CE,[3] W-4-LP
NRC Notified By: FRED NYGARD
HQ OPS Officer: BILL GOTT
Notification Date: 12/21/2006
Notification Time: 09:24 [ET]
Event Date: 12/21/2006
Event Time: 02:05 [EST]
Last Update Date: 12/21/2006
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(3)(v)(D) - ACCIDENT MITIGATION
Person (Organization):
RAY POWELL (R1)

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

Event Text

ACCIDENT MITIGATION - AUXILIARY FEEDWATER SYSTEM

"A condition was identified [at 0205 on 12/21/06] involving improper placement of temporary scaffolding that could have resulted in all three Auxiliary Feedwater (AFW) pumps becoming inoperable during a high energy line break (HELB) in the Turbine-Driven Auxiliary Feedwater (TDAFW) pump room.

"Scaffolding, erected to perform maintenance on the floor above the TDAFW pump room, had two vertical members placed on the high energy line break blowout panel in the TDAFW pump room roof that could potentially have restricted the ability of the panel to lift during a HELB event in the TDAFW pump room. Failure of the panel to lift during the event may cause the structural limit of the walls separating the TDAFW pump room from the motor driven AFW pump room to be exceeded. This could have resulted in all three AFW pumps becoming inoperable.

"At 0530 on 12/21/06, scaffolding removal was complete and AFW operability was restored.

"This condition is being conservatively reported, pending further evaluation, per 10CFR50.72(b)(3)(v) as a condition that at the time of discovery could have prevented the fulfillment of a safety function."

The licensee notified the NRC Resident Inspector.

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Power Reactor Event Number: 43060
Facility: SUSQUEHANNA
Region: 1 State: PA
Unit: [1] [2] [ ]
RX Type: [1] GE-4,[2] GE-4
NRC Notified By: JIM HUFFORD
HQ OPS Officer: BILL HUFFMAN
Notification Date: 12/21/2006
Notification Time: 14:46 [ET]
Event Date: 12/21/2006
Event Time: 14:00 [EST]
Last Update Date: 12/21/2006
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(2)(xi) - OFFSITE NOTIFICATION
Person (Organization):
RAY POWELL (R1)

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

INADVERTENT ACTUATION OF EMERGENCY SIRENS

"A Press Release will be issued for an inadvertent actuation of the Emergency Sirens during testing. This item is reportable under 10CFR50.72(b)(2)(xi) as an offsite notification of an event of public interest."

Following maintenance on a single siren, Columbia County emergency management personnel were requested to test it. The County inadvertently activated all 112 sirens within 10 miles of the plant.

The licensee notified the NRC Resident Inspector and the State.

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