ML20086D317

AO 75-018:on 750901,steam Supply Valve 13-15 Failed to Close When Control Switch Placed in Closed Position.After Repeated Attempts,Valve 13-15 Responded & Cycled Closed.Valve Stroked,Timed to Ensure Operability & Declared Inoperable

ML20086D317
Person / Time
Site:	Vermont Yankee
Issue date:	09/02/1975
From:	Riley B VERMONT YANKEE NUCLEAR POWER CORP.
To:	James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML20086D315	List: ML20086D317
References
AO-75-018, AO-75-18, VYV-3982, NUDOCS 8312010147
Download: ML20086D317 (1)

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, September 2, 1975 United States Nuclear Regulatory Cominnion Office of Inspection and Enforcement Region I .

631 Park Avenue -

King of Prucaia, PA 19406 ATIENTION: J5mos P. O'Re131y, Director

REFERENCE:

Operating License DPR-28 '

Docket No. 50-271 Abnormal Occurrence No. AO-75-18 (24 Hour Report)

Dear Sir Ao defined by Technical Specifications for the Vermont Yankee Nucicar

- Power Station, Section 6.7. we are roporting the following Abnorma) Occur-rence an AO-75-18 and confirming our conversation with your office.

At approximarcly 0256 on September 1, 1975. While performing routino surveillat 'o on the RCIC System, Steam Supply Valve 3 3-15 failed to close when the control switch was placed in the CLOSE position. Thia valvo also perforns a primary containment isolation function and therefore the operator's imediato action was to clone Valve 13-16 in accordanco with Technle.21 Spec-ification 3.7.D.2. Valve 13-16 closed in response to the control cuitch being placed in the CLOSE position, however, the valve position indicator lights in the Control Room indicated that the valve was- cycling from full OPEK I

to full CLOSED and back to full OPEN. The operator then opened the electrical breaker to Valve 13-16 when the 11Rhtn indicated that van CLOSED.,This action rendered the ECIC System inoperable. The HPCIitSystem .

was then tested and 4.5.G.2.demonstrated to be operable in accordance with Technical Specification At approximately 1000 on September 1, Valve 13-15 responded and was cycled CLOSED.1975, af ter repeated attempts, and timed neveral times to ensure ita operability This valve was then stroked l operable at that time. and was declared fully 1 Work is presently in progrecs to repair Valve 13-36.

1 plant The plant van andgradually was at being increased in power in accordance with I

procedures i

this incident. approximately 63% of rated power. at the time of 1

1 Very truly urs, kk$ DOC O *

- - I s Bradford W.

WPM / cam - iley %M cc: 1.18.2 Plant Superintendent V i - -

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