ML20080N339

RO SPR-84-1:on 840106,specific Activity Sample of Reactor Coolant Showed Peak Dose Equivalent I-131 Level Exceeded Tech Spec Limits.Caused by Known Fuel Element Defects in Core.Tech Spec Requirements Implemented

ML20080N339
Person / Time
Site:	Surry
Issue date:	02/13/1984
From:	Joshua Wilson VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:	James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
References
RO-SPR-84-1, NUDOCS 8402220208
Download: ML20080N339 (2)

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vlRGINIA ELECTRIC AND POWER COMPANY 84 f EB 16 A 8,. 5 8 ,,,,,,,_,,,,,,,,

P. O. 8,x 315 Surry, Virginia 23883 FEB 131984 Serial No: SR-84-01 Docket No: 50-280 License No: DPR-32 Mr. James P. O'Reilly Regional Administrator Suite 2900 101 Marietta Street, NW Atlanta, Georgia, 30303

Dear Mr. O'Reilly:

Pursuant to Surry Pcwer Station Technical Specifications, the Virginia Electric and Pcwer Ccrapany hereby suhnits the following Special Report for Surry Unit 1.

Report Number Applicable Technical Specification SPR-84-1 6.6.2.b. (2) & 3.1.D.4 This report has been reviewed by the Staticn Nuclear Safety and Operating Cmmittee and will be reviewed by Safety Evaluation and Control.

Very truly yours, s

J. L. Wilson Staticn Manager Enclosure cc: Document Control Desk, USNRC 016 Phillips Building Washington, D. C., 20555 N khD 0 Dh 8 'dFFICIAL COPY

$36 s*

SmY POWER STATION, UNIT -NO.1 DOCKET NO: 50-280

' REPORT NO: SPR-84-1 EVENT.DATE: 1-6 TITLE OF THE EVENT: SPECI AL REPORT PURSUANT TO T.S.3.1.D.4 DOSE EQUIVALENT I-131 > 1.0'MICROCURIES/cc.

Description of the Event

0n January 6,1984, at 1530, following a unit trip from 100%, the specific activity' sample of the reactor coolant showed a peak dote equivalent I-131 level of 1.57 microcuries/cc. This exceeds the dose equivalent I-131 T.S.3.1.D.2 limit of <- 1.0 micracuries/ce' and is reportable per T.S.6.6.2.b.(2) and the special' reporting requirements of T.S.3.1.D.4.

Probable Consequences and Status of Redundant Equipment The limitations on the specific activity of the primary coolant ensure that the resulting 2 hour2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> doses at the site boundary will not exceed an appropriately small fraction of 10 CFR 100 limits following a postulated steam

. generator tube rupture. Since the dose euqivalent I-131 peak was below the Technical Specification' upper limit of 10 microcuries/ce, the reactor coolant

- gross activity.vas below the value analyzed in the FSAR for a tube rupture and

~-l% f ailed ' fuel.' - Therefore, the health and safety of the public were not affected.

'Cause-The Iodine Spike was caused by known, yet'not specifically located, fuel element defects in the reactor _ core. Post trip conditions enhanced the release of fission products, specifically I-131 which caused an increase in the coolant

-ppecific activity level.

Immediate Corrective Action The immediate corrective action was to implement the actions required by T.S.

Table 4.1.2.B. c Specifically, the level dose equivalent I-131 was monitored every 4' hours entil the level returned to less than- 1.0 microcuries/cc.

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Raport No. SPR-84-1 SUPPLEMENTAL INFORMATION

-The supplemental information required by T.S,3.1.D.4 "Special Report" is included as follows:

1. Reactor Power History 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> prior to the event:

January 4, 1984 - 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> at 100%

January 5, 1984 hours0.023 days <br />0.551 hours <br />0.00328 weeks <br />7.54912e-4 months <br /> at 100%

January. 6, 1984 - 1324 - Reactor Trip from 100%

2. Fuel burnup by core region - as of January 6,1984 Fuel Batch  : S2/6B: 29002 M!1D/MTU 6C: 30371 MWD /MTU 4C: 30709 MWD /MTU 7A: 27788 MWD /MTU 8A: 25216 MWD /MTU 8B: 24717 MRD/MTU 9: 6584 MWD /MTU Cycle ' 7 Burnup : 5766 : MRD/MTU

3. Prior to the reactor trip, the unit had established a normal letdown rate of 107 gpm.

4. No De-Gassing' operations were performed.

~5. Duration of I-131 Spike:

January 6, 1984 - 0035 - Routine Sample .113 microcuries/cc.

1530 - Post' Trip Sample 1.57 microcuries/cc.

1730 - Post Trip Sample 1.32 microcuries/ce.

1930 - Post Trip Sample 1.03 microcuries/cc.

2130 - Post Trip Sample .891 microcuries/cc.

Duration approximately 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.

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