Event Notification Report for March 23, 2012

U.S. Nuclear Regulatory Commission
Operations Center

Event Reports For
03/22/2012 - 03/23/2012

** EVENT NUMBERS **


47760 47764

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Power Reactor Event Number: 47760
Facility: COOPER
Region: 4 State: NE
Unit: [1] [ ] [ ]
RX Type: [1] GE-4
NRC Notified By: ROBERT LECHNER
HQ OPS Officer: PETE SNYDER
Notification Date: 03/22/2012
Notification Time: 11:56 [ET]
Event Date: 03/22/2012
Event Time: 10:34 [CDT]
Last Update Date: 03/22/2012
Emergency Class: UNUSUAL EVENT
10 CFR Section:
50.72(a) (1) (i) - EMERGENCY DECLARED
50.72(b)(2)(xi) - OFFSITE NOTIFICATION
Person (Organization):
MICHAEL HAY (R4DO)
ELMO COLLINS (R4)
BRUCE BOGER (NRR)
JEFFERY GRANT (IRD)

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

NOTICE OF UNUSUAL EVENT - POTENTIALLY HAZARDOUS ATMOSPHERE DUE TO FREON LEAK

At 1034 CDT on 3/22/12, Cooper Nuclear Station declared a Notice of Unusual Event due to a freon leak from a glycol compressor in the sub-basement of their Augmented Radwaste Building. This created a potentially unsafe localized atmosphere in that area per Emergency Action Level HU 3.1.

The licensee made a public address system announcement to avoid the area and sent personnel to guard the area to prevent entry.

The licensee is monitoring the area for any deterioration. Oxygen levels are currently normal. Cooper Nuclear Station personnel plan to isolate the freon leak and ventilate the area to ensure a habitable atmosphere.

There are no safety related systems or components in the affected area. Plant operation is unaffected. As of 1045 CDT, the licensee has notified appropriate state and local governmental agencies.

The licensee notified the NRC Resident Inspector. Notified DHS SWO, DHS NICC, FEMA and Nuclear SSA via email.

* * * UPDATE AT 1320 EDT ON 3/22/12 FROM ROBERT LECHNER TO PETE SNYDER * * *

Cooper Nuclear Station personnel monitored the atmosphere in the affected area for safe entry then entered and isolated the freon leak. They did further extensive monitoring for any pockets of trapped freon gas and further ventilated the area to restore the area to a habitable condition. At 1142 CDT Cooper Nuclear Station exited their Unusual Event condition.

Offisite notifications were made per 10 CFR 50.72 (b)(2)(xi). A press release is planned to inform the public of this onsite event.

Notified DHS SWO, DHS NICC, FEMA and Nuclear SSA via email

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Power Reactor Event Number: 47764
Facility: MCGUIRE
Region: 2 State: NC
Unit: [ ] [2] [ ]
RX Type: [1] W-4-LP,[2] W-4-LP
NRC Notified By: SCOTT WARREN
HQ OPS Officer: PETE SNYDER
Notification Date: 03/22/2012
Notification Time: 22:53 [ET]
Event Date: 03/22/2012
Event Time: 21:30 [EDT]
Last Update Date: 03/22/2012
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(3)(ii)(B) - UNANALYZED CONDITION
Person (Organization):
ROBERT HAAG (R2DO)

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

POTENTIAL FIRE INDUCED SPURIOUS OPERATION OF STEAM GENERATOR BLOCK VALVES

"On February 28, 2005, Duke Energy notified the NRC of McGuire Nuclear Station's (MNS) intent to adopt NFPA 805 in accordance with 10 CFR 50.48(c). On April 18, 2006, Duke Energy notified the NRC that MNS had begun the process of transitioning to NFPA 805. For licensees transitioning to NFPA 805, assuming specific criteria are met, the NRC will exercise enforcement discretion for Appendix R non-compliances identified during the transition process and for existing Appendix R non-compliances that could reasonably be corrected under 10 CFR 50.48(c). As per NRC guidance and policy, enforcement discretion does not relieve the licensee of the requirement to make a required report to the NRC.

"As part of the NFPA 805 transition process, MNS has identified Appendix R related noncompliances which are being evaluated for appropriate dispositioning under NFPA 805. The evaluation of the non-compliances has recently identified a condition which could result in fire induced spurious operation of the block valves for the Unit 2 Steam Generator (SG) Power Operated Relief Valves (PORVs). This spurious operation could potentially damage these valves and render them inoperable. Since these valves are unisolable, they could not be repaired to allow the Unit 2 SGs to be used for Unit cool down if needed.

"This potential condition could adversely affect the ability of the plant to achieve and maintain a cold shutdown of Unit 2. This represents a condition reportable as per the requirements of 10 CFR 50.72(b)(3)(ii)(B). This potential condition is mitigated by existing compensatory measures (i.e. fire watches) which have been in place as part of the NFPA 805 transition.

"The NRC Resident Inspector has been notified."

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