ML20090E041

AO 50-220/75-05:on 750401,during Routine Surveillance Testing,Emergency Vent Sys Failed to Function When Sys Inlet Ventilation Valve Bv 202-36 Failed to Open.Caused by Broken Stem in Solenoid Valve.Solenoids Will Be Replaced

ML20090E041
Person / Time
Site:	Nine Mile Point
Issue date:	04/02/1975
From:	NIAGARA MOHAWK POWER CORP.
To:	James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML20090E038	List: ML20090E041
References
AO-50-220-75-5, NUDOCS 8303110442
Download: ML20090E041 (2)

Text

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N6 AGAMA MOHAWK POWER CORPORATION

. NIAGAn4 MOHWWE a

DATEt- April 2. M75

SUBJECT:

Abnormal Occurrence Report No. 50-220 75- 5 (24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> Kotification) 1he enclosed preliminary AOR is being submitted in accordance with Technical specification Section 6 Cbnfirming C. Stuart phone conversatica with April 1,1975 AEC RO:I office on 102 James P O'Rei!2y -

- Directorate of Regulatory Operations s- Rsgion 1 631 Park Avenue King of' Prussia, Pa. 19406 Pit 3f: Niagste Fbhawk Power Corporation Nine Nils Point - James A. FitzPatrick Site P.O. Box #32 f,ycoming,, New York 13095 Docket No. 50 _ 220 REFERENCEL License DPR- 63 Report No,t 50- m /75- S Report Date 4-2-75 Occurrence Date 4-I-75 -

Pacility: NY te!P-I .

g Identification of Occurrance:

Failure er the Emergency Venti 2ation Systems to ibnctierr as designed genen initiated during routine- surveillmace testing.

t 8303110442 750414 gDRADOCK 05000220 PDR

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PAGE 2 o Conditions Prior to Occurrence: 94.51L Steady State Power Routine Shutdown Rat Stundby Cold Shutdown Rad Changes

~ Refueling Shutdbwa Routina Startup other-Description of the Occurrer.ce:.

He Dnergency Ventilation System is a standby system designed to operate to mitigate the consequences of high radiation levels in the normal ventilation system. During routine operater surveillance (Tech Spec;. 4.4.4 aner Tables. 3.6r.2J f 4.6.2j). H e system inlet ventilation valve (B.V 202-36} f&iled to open.. due to a broken stem in one RPS solenoid valve and metal filings- in the other

(% Iogic).

Aphrarent Cause of the occurrence:

Design Procedure Manufacture Unusual Service Condities Installatica/

Coast.

Operator I Camrponent Failure Analysis of Occurrence:

he system was inmediately restored to service and thus would have performed its intended function. Even without system operation under the worst condition,. the site boundary doses- would have been less than required by 10' CFR.100*. Herefore, no hazard was to the general public. He RPS solenoids will be replaced. presented

Corrective Actions.

he blocking valve- 202-35 was immediately cp.-d (=====11y) thus satisfying the requirements of Tech Spec 3.4~.4.

has been- ordered; by SORC te evaluate operaties- withAn Engineering 202-36 normallyReview of the system open and. the related RPS ihneticos.

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Failure Pata: ,

ASCO Yhlve SN'831639-a.

• FE&R Supplement t VI.It' ,,

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