ML20086J354

Telecopy AO 74-14:on 741015,inboard Main Steam Line Sample Isolation Valve Found Not Fully Closed.Cause Unknown.Daily Log of Other Operable Isolation Valve Instituted.Test Conducted to Prove Isolation Capability of Outboard Valve

ML20086J354
Person / Time
Site:	Peach Bottom
Issue date:	10/16/1974
From:	Ullrich W PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC
To:	James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML20086J326	List: ML20086J325 ML20086J342 ML20086J354
References
AO-74-14, NUDOCS 8401230588
Download: ML20086J354 (2)

Text

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ILADELPHIA ELECTRIC COMPANY P ch Bottom Atomic Power Station O

Delta, Pennsylvania 17314 October 16, 1974 Mr. James P. O'Reilly, Director United States Atomic Energy Coenission Directorate of Regulatory Operations 631 Park Avenue King of Prussia, Pennsylvania 19406

Subject:

Abnormal Occurrence 24-Hour Notification Confirming W. T. U11 rich's phone conversation with Mr. Walt Baunack, A.E.C.

Region 1 Regulatory Operationa office on October 16, 1974. . -

Reference:

License Number DPR-56 Technical Specification Reference 3.7.D .

Report No.: 50-278-74-14 Report Date: ,0ctober 16, 1974 Occurrence Date: October 15, 1974 Facility: Peach Botton Atomic Power Station -

R.D.1, Delta, Pennsylvania 17314 ,

4 Identification of Occurrence: Eg . s .=-

Unit 3 inboard main steam line sample isolation valve not fully closed. Q rR;.,h .

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Conditions Prior to Occurrence:

Unit 3 reactor shutdown, reactor pressure approximately 100 psig, ib 8 y %g f

l-reactor temperature approximately 340*F, reactor ready for startup. IffO.i

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Description of Occurrence:

During a routine inspection of the control room panels, an operator

• )[ib noticed that the inboard main steam line sample isolation valve was d; indicating mid-position. The outboard isolation valve vas immediately

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verified to be in the closed position which is the normal position for both isolation valves.

Designation of Apparent Cause of Occurrence:

Unknown at this time. Requires drywell entry to investigate.

Analysis of Occurrence:

At the time of this occurrence, the reactor was shutdown and at reduced temperature and pressure. The other isolation valve in the line was verified '

to be in the closed position and, as described below, tested to verify its isolation capability. Since one valve in the line was closed and leak tight, this occurrence has minimal safety implications.  :

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... t Corrective Action:

As required by the Technical Specifications, a daily log of the other operable isolation valve was immediately instituted, in the form of an established surveillance test which verifies that the position of the other isolation valve, in the same line, is in the closed or isolated condition. A test was conducted to prove the isolation capability of the outboard valve. Flow through the line was established, and when the outboard isolation valve was closed, flow ceased. In addition, the normal plant blocking procedures were applied to the~ outboard valve to ensure ~that the--'-

valve remained in the closed or isolated condition, until the inboard isolation valve was repaired.

Failure Data:

None.

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