ML20086E639

AO 74-07:on 740509,spike Observed on Plant Stack Gas Recorder,Resulting in Stack Release Peak Greater than Allowed by Tech Specs.Cause Not Stated

ML20086E639
Person / Time
Site:	Vermont Yankee
Issue date:	05/10/1974
From:	Riley B VERMONT YANKEE NUCLEAR POWER CORP.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML20086E638	List: ML20086E636 ML20086E639
References
AO-74-07, AO-74-7, VYV-3269, NUDOCS 8312070465
Download: ML20086E639 (1)

Text

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./ VEIDIONT YANKEE NUCLEAR POWER CORPORATION SCVCNTY SCVCN OROVC STRCCT RUTLAND, VEIO10NT 03701 REPLY TO:

VW3269 P. D. DOX 157 .

VERNON VERMONT c5354 May 10, 1974

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Director Directorate of Regulatory Operations, Region I United States Atomic Energy Commission k f[ h j{

631 Park Avenue 5 y -

King of Prussia, Pennsylvania 19406 { ##- ,

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REFERENCE:

Operating License DPR-28 1

d Docket No. 50-271 '/

Abnormal Occurrence No. A0-74-07 (24 Hour Report)  % TG [

Dear Sir:

l As defined by Technical Specifications for the Vermont Yankee Nuclear Power Station, Section 6.7, we are reporting the following Abnormal Occurrence l nn AO-74-07 and ennfirmino nne talanhnna enmeave n t ina uith ye.:r effi:2, '

At approximately 1212 on May 9, 1974, during a plant cooldown following a reactor manual scram, an apparent spike was observed on the plant stack '

gas recorder which resulted in a stack release peak of 0.450 Ci/sec. This incident was determined to be in violation of Technical Specifications, Section 3.8.C.l.a in that the maximum release rate of gross radioactivity from the plant did exceed 0.08/Ey Ci/sec = (0.257 Ci/sec) for a period of tan seconds. Prior to the apparent spike, the release rate had been decreasing for approximately four minutes and was at a value of 0.135 Ci/sec. Immediately following the peak, the release rate was 0.120 Ci/sec. and continued on a steady downtrend for the following half hour.

The annual average stack release rate since January 1, 1974, and including this transient is 2,252 pCi/sec. which is approximately 1%

of the allowable release rate.

Very truly yours, l s

0 VERMONT YANKEE NUCLEAR POWER CORPORATION O

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BC .

B. W. Riley g

Plant Superintendent WFC/sfw

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