ML19326A065

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RO on 720926,two Pumps in Standby Liquid Control Sys Inoperable at Same Time.Caused by racked-out Pump Breaker. Breaker racked-in & Operations Procedures Revised
ML19326A065
Person / Time
Site: Davis Besse, Oyster Creek
Issue date: 10/06/1972
From: Finfrock I
JERSEY CENTRAL POWER & LIGHT CO.
To:
Shared Package
ML19326A046 List:
References
NUDOCS 8001310638
Download: ML19326A065 (2)


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Jersey Central Power & Light Company 0

MADISQN AVENUE AT PUNCN SQW1. RQ AQ e MORRISrCWN. N.J. o796o e 339 611:

October 6,1972 Mr. A. Cia =busso Deputy Director for Reactor Projects Directora:e of Licensing United States A::=le Energy Cc==ission hshingte:., D. C. 20545 9 my w

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Dear Mr. Cia =busso:

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Subject:

Cys:cr Creek S:ation Docket No. 50-219 Inoperable S:andby Liquid Centrol Syste:

'Ihe purpose of this letter is to rapor: to yo'u an inciden:

that occurred a: Oyster Creek en Sep:c=ber 26, 1972 in which 1: was discovered tha: :he two pe=ps in the s:andby liquid control syste=

were inoperable at the sa=e ti=c.

At 10:45 a.=.'on Sep:c=ber 25, 1972, the "A" standby liquid con:rci pu=p was rc=oved frc= service for replace =en: of the pu=p packing. The pu=p was taken ou: of service using Technical Specifica: ion 3.2.C.3 as :he basis.

It s:stes, "If one standby liquid centrol syste= pu= ping circuit becc=es in-operable during the run =cde and specifica:ica 3.2.A is =et,

.the reactor =ay re=ain in opera:ica for a period not :o exceev c,even days, provided the pu=p in the other circui: is dc=on-strated daily to be operable". Specifica:ica 3.2.A is =et, therefore, the "A" pu=p breaker was racked cut and the pu=p secured in accordance with plant safety procedures. The wars was not cc=ple:cd by :he end of the day shift, and the "A" pu=p was left in an inoperable condi:icn. At 4:20 a.=. cn Septe=ber 26, 1972', the "3" liquid con:rol syste= pu=p was to be run to ec= ply with Technical Specification 3.2.C.3.

When the operator depressed the start butten, the pu=p did not start.

An interlock in the starting circuitry prevents vo standby liquid control pu=ps frc= being run s1=ultaneously.

This interlock also preven:s the "3" pu=p frc= star:ing when the "A" pu=p breaker is in :he racked ou: positicn. The interlock is ce=pesed of a nor= ally closed contact in the starting circuit of each pu=p.

This contac: is opera:ed from a relay in the opposite pu=p circuit.

If the "A" standby liquid control pu=p is s:ar:ed either frc= the control roo= with the key lock switch or locally frc= the 8001310

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.. I push button statica, a relay is picked c'p which opens the nor= ally closed con:act in the "3" standby liquid control pu=p starting circuit which preven:s this pu=p frc= opera:ing with the "A" pu=p running. The reverse is truc if :he "3" pu=p is started.

The proble= developed when the breaker for the "A" pu=p was racked out.

It disabled the pu=p and at the sa:e ti=c it physically re=oved the contact in :he s:arting circuitry for the "3" pu=p which si=ula:cd an open cen:ac:. This preven:ed the "B" pu=p from starting.

As soon as the Shif t Fore =an was aware of the inoperability of both pu=ps, he star:ed a nor=al shutdcun of the plan:.

In the meanti=e, he received per=1ssion to clear the =aintenance safety tags and rack the "A" pu=p breaker to its nor=al posi: ion. He then ran a successful operabili:y check on the "3" pup.p.

The load redue:1on was s:opped and the plan: re:urned to full load.

In order c' prevent a recurrence of this event, operating procedures have been changed so that operabili:y :es:s of redundan:

engineered safeguards syste: cc=penen:s vill be =ade i==edia:ely following any action :ha: requires one of the sys:c=s to be inoperable for =ain:enance purposes.

We are enclosing forty copics of this letter.

Very truly yours,

[$7 }. M'l E O IvanR.Finfrock,J;f p

Vice Presiden:

IRF/pk Enclosures cc: Mr. J. P. O.'Rei,lly, Director Directorate of Regula:ory Operations, Region 1

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