ML19316A611

Unusual Event 270/75-13:on 750731,one Train of Reactor Bldg Spray Removed from Svc.Caused by Insufficient Trainee Supervision.Proper Identification of Components Emphasized & Trainee Supervision Discussed W/Personnel

ML19316A611
Person / Time
Site:	Oconee
Issue date:	08/27/1975
From:	DUKE POWER CO.
To:
Shared Package
ML19316A609	List: ML19316A608 ML19316A611
References
RO-270-75-13, NUDOCS 8001130123
Download: ML19316A611 (1)

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1 DUKE POWER COMPANY i OCONEE UNIT 2 ,

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! l 1 Report No.: UE-270/75-13 Report Date:' August 27, 1975 1

i Event Date: ; July 31, 1975 Facility:_ Oconec Unit 2, Seneca, South Carolina l Identification of Event: One train of Reactor Building Spray inadvertently taken out of service .

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Conditions Prior to Event: Unit at 100 percent full power i

f I Description of Event:

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On July 31, 1975, the Reactor Building Spray Engineered Safeguards Test was performed on Oconec Unit 1. In the performance of the test, the l

Control Operator instructed the Utility Operator to open the breaker for valve 1BS-2. A Utility Operator's trainee inadvertently opened the Unit 2  !

breaker for valve 2BS-2, thereby removing one train of Reactor Building 4

l The breaker to 2BS-2 was opened l f

spray from service on an operating unit. '

approximately 20 seconds until the Utility Operator acknowledged a Unit 2 l alarm and had the trainee close the breaker for valve 2BS-2.

Designation of Apparent Cause of_ Event:

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The apparent cause of this event was operator error in that the trainee The was not adequately supervised and operated the breaker on the wrong unit.

breakers were clearly identified as to valve number and unit number.

Analysis of Event:

This incident resulted in one train of Reactor Building spray being inoperable <

for approximately 20 so. nds. The redundant train of building spray and the

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j entire Reactor Building Cooling System were operabic during this time and would have furttioned properly is needed. It 13 concluded that the health >

and safety of the public was not affected.

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Corrective Action:

The personnel involved in this incident have been reminded of the importance of assuring that they properly identify components prior to operation. The I

Shift Supervisor is discussed with personnel the necessity for proper comst. ". cations and proper supervision of trainees to avoid future occurrences.

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4 8001130 g )

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