ML20010G326

Forwards LER 81-051/03L-0.Detailed Event Analysis Encl

ML20010G326
Person / Time
Site:	Fort Saint Vrain
Issue date:	08/20/1981
From:	Warembourg D PUBLIC SERVICE CO. OF COLORADO
To:	Seyfrit K NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
Shared Package
ML20010G327	List: ML20010G326 ML20010G337
References
P-81206, NUDOCS 8109150591
Download: ML20010G326 (4)

Text

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• PLATTEV1LLE, COLOR ADO 80651 August 20, 1981 Fort St. Vrain Unit No. 1 .

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S Mr. Karl V. Seyfrit , Director Nuclear Regulatory Commission O Region IV d i

Office of Inspaction and Enforcemnt 611 Ryan Plaza Drive 4[gf Euite 1000 i Arlington, Texas 76012 Re fe rence : Facility Operating License No. DPR-34 Docket No. 50-267 Dea- Mr. Seyf rit:

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) Enclosed please find a copy of Reportable Occurrence Report No. 50-267/ t' i 81-051, Final, submitted per the requiremnts of Technical Specification AC 7.5.2(b)2.

Also, please find enclosed one copy of the Licensee Event Report for i

Reportable Occurrence Report No. 50-267/81-051.

Very cruly yours ,

- WA.uJ Don Warembourg Manager, Nuclear Production DU/cls Enclos ure cc: Director, MIPC

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FAPvRT DATE: August 20, 1981 REPORTABLE OCCURRENCE 81-051 ISSUE O CCCURRENCE DATE: July 21, 1981 Page 1 of 3 FORT ST. VRAIN NUCLEAR GENERATING STATION PUBLIC SERVICE COMPANY OF COLORADO 16805 WELD COUNTY ROAD 19 1/2 PLATTEVILLE, COLORADO 80651 REPORT NO. 50-267/81-051/03-L-0 Final IDENTIFICATION OF OCCURRENCE:

On four occasions, with the plant operating at power, Class I snubbers were taken out of service. This is being interpreted as a degraded mode Of LCO 4.3.10 and reportable per Fort St. Vrain Technical Specification AC 7.5.2(b)2.

EVENT DESCRIPTION:

Event #1 On July 21, 1981, with the plant operating at 16% power, snubber H0$-28 was taken out of service from 0745 hours0.00862 days <br />0.207 hours <br />0.00123 weeks <br />2.834725e-4 months <br /> until 1125 hours0.013 days <br />0.313 hours <br />0.00186 weeks <br />4.280625e-4 months <br /> for structural modifications.

Event #2 On August 5, 1981, with the plant operating at 57% power, snubber BFS-823 wi.s taken out of service from 1045 hours0.0121 days <br />0.29 hours <br />0.00173 weeks <br />3.976225e-4 months <br /> until 1440 hours0.0167 days <br />0.4 hours <br />0.00238 weeks <br />5.4792e-4 months <br /> for structural modifications.

Events #3 and #4 On /.ugust 6, 1931, with, the plant operating at 70% power, snubber BFS-556 was taken cut of service from 0730 hours0.00845 days <br />0.203 hours <br />0.00121 weeks <br />2.77765e-4 months <br /> until 1300 hours0.015 days <br />0.361 hours <br />0.00215 weeks <br />4.9465e-4 months <br />, and snubbers Br$~553-1 and -2 were. taken out of service from 1300 hours0.015 days <br />0.361 hours <br />0.00215 weeks <br />4.9465e-4 months <br /> until 1600 hours0.0185 days <br />0.444 hours <br />0.00265 weeks <br />6.088e-4 months <br /> for structural modifications. .

In all instances, the snubber itself was not inoperable, but was required tc be di; connected to provide accessibility for structural modifications.

CAUSE DESCRIPTIONS:

The snubbers were taken out of service for structural modifications consisting primarily of weld builcuos required by the seismic restraint analysis program.

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REPORTABLE OCCURRENCE 81-051 ISSUE O Page 2 of 3 CORRECTIVE ACTI0ft: ,

The snubbers were returned to service upon completion of the modifications.

No further corrective action is anticipated or required.

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REPORTABLE OCCURRENCE 81-051 ISSUE O Page 3 of 3 Prepared By: M Paul'Moora Technical Services Technician I

Reviewed By: [ c((A /pr A62//4.&M fiilt McBride '

Technical Services Manager

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Edwi&D. Ht1T

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Station Manager l

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Don Warembourg Managee, Nuclear Production t

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