PNO-I-97-049, on 970807,inadvertent Actuation of Halon Sys Occurred Affecting CR & Adjacent Central Alarm Station. Personnel Took Photographs of Panel of Halon Actuation Panel,Prior to Actuation.Root Cause of Actuation Evaluated

PNO-I-97-049:on 970807,inadvertent Actuation of Halon Sys Occurred Affecting CR & Adjacent Central Alarm Station. Personnel Took Photographs of Panel of Halon Actuation Panel,Prior to Actuation.Root Cause of Actuation Evaluated

ML20198F880
Person / Time
Site:	Haddam Neck File:Connecticut Yankee Atomic Power Co icon.png
Issue date:	08/08/1997
From:	Conte R, Raymond W NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
To:
References
PNO-I-97-049, PNO-I-97-49, NUDOCS 9708130174
Download: ML20198F880 (2)

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' August 8, 1997 ERELIMIEABI_KQTH I.93 TION OF EVENT OR' UNUSUAL OCCUPDMNCE-PNO-I-97-049

-This -preliminary: notification constitutes EARLY notice of events of POSSIBLE-

'feafety;or public interest--significance. The information is~as initially recaived without verification or evaluation, and-is basically all that is knowniby-Region I staff in King of Prussia, Pennsylvania on this date.

u Facility _

Licensee Emeroency Classification j Connecticut Yankee Atomic Power Co. X Notification of Unusual-Event j L Haddam Neck.1 Alert-Hartford, Connecticut Site Area Emergency LDockatsif50-213 General Emergency Not 7@plicable

Subject:

L CONTROL ROOM EVACUATION DUE TO INADVERTENT RALON ACTUATION -

MEDIA' INTEREST On' August 7,_1997 at 9:47 a.m., an inadvertent: actuation of the halon

- cystem occurred af fecting the control room- (CR) and the adjacent central alarm station-(CAS). Within 6 minutes, personnel evacuated those areas.

The secondary alarm station (SAS) functioned to fully back up CAS. After-ventilatingithe control room and airiquality was assessed as satisfactory, operators, returned to the CR at about 10:34 a.m. Based on-conservative judgement, the shift manager declared an Unusual-Event at 710:45 a.m.- After-stable conditions.were reverified-in the control room, and in consultation with plant management, plant operators exited from

-.the Unusual Event at 12:35 p.m. There were no injuries.

Just prior to the actuation, personnel were taking photographs of the penal-of the halon actuation panel. After the discharge, the halon bank -

was declared' inoperable and a_ fire watch was initiated in the CR as a by :theilicensee's event -The rootteam.

cause of the actuation is being evaluated compensatory measure.

review LPrior to CR evacuation,-the shift manager confirmed there was no fire.

During the evacuation period, operators gathered in an adjacent room with a-window and were able to observe the control room panels. While operators =were in the adjacent room, the CAS operator re-entered the CAS iniself- contained breathing apparatus (SCBA) by 10:09 a.m._ An operator Lwithout-:'SCBA briefly re-entered the CR at times to respond to-alarms as-they occurred. 'The licensee reported no effect on spent fuel pool

-cooling, service water, electrical distribution and radiation monitoring.

There was no significant equipment-damage.

JTha resident inspector responded to the site. The State of Connecticut

.was. notified by both the licensee and. Region I. The licensee issued a press release. A Commissioner Technical Assistants briefing was conducted at 3:00 p.m.

!Region I initially received notification of the event from the Senior

-Resident Inspector at 10:30-a.m.,-August 7, 1997.  %

9700130174 970008 ' .[L PDR IhE PNO-I-97-049 PDR ,,

L 100080

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The information-_ presented herein has-been discussed with the licensee, cnd-is current as of-4:00 p.m., Thursday, August 7, 1997.

Contcet: RAYMOND,. WILLIAM CONTE, RICHARD (203)267-2571 (610)337-5183 I

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