ML20099K294

Ro:On 920807,auxiliary Bldg Vent Stack wide-range Noble Gas Monitor Declared Inoperable Due to Inability to Pass Source Check.Caused by Failure of High Voltage Power Supply. Original Detector Reinstalled After Addl Failure

ML20099K294
Person / Time
Site:	Braidwood
Issue date:	08/18/1992
From:	Kofron K COMMONWEALTH EDISON CO.
To:	Davis A NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
References
BW-92-0444, BW-92-444, NUDOCS 9208260024
Download: ML20099K294 (2)

Text

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. August 18, 1992 BW/92-0444 Mr. A. Dert Davis Regional Administra;or

'J . S. Nuclear Regulatory Commission Region III 799 Roosevoit Road Glen Ellyn, Illinois 60137

Subject:

Braidwood Station Units 1 and 2

-Auxiliary Building Vent Stack Wide Range Noble Gas Monitor Inoperability HRC Docket Noe. 456 and 457 References (a) NUREG-1276, Technical Specifications Dear Mr. Davist Braidwood Station Technical Specification 3.3.J.6 Action (c) requires that with less than the minimum number of auxiliary building vent stack wide range noble gas monitors operable for more than 7 days, a 3pecial Report

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shall be prepared and submitted to the Commia lon within 14 days pursuant to Specification 6.9.2 that provides the actions taken, cause o' the ir. operability, and plans and schodule for restoring +Le channel (s) to operable statua. Pursuant to these Specifications, the enclosure provides a report regarding the inoperability of the Unit 2 Auxiliary Building Vent Stack Wide Range Noble Ga Monitor, 2PR30J, initisted August 7, 1992 at 1100 hours0.0127 days <br />0.306 hours <br />0.00182 weeks <br />4.1855e-4 months <br />. The inoperability of 2PR30J af fects both Braidwood Units 1 and 2.

Please direct any questions regarding th!s submittal to Harry Pontious, Braidwood Station Licensing Coordinator, extension 2511.

Very truly yours, I

t s

ti e l .

e K. L. Kofron Station Manager l- Braidwood Nuclear Station l

4 LLK/HDP/dla l 20ZCREG i

Enclosure cc R. Pulsifer - NRR i B. Cinyton - RIII

-Resident Inspector Braidwood

.NRC Document Control' Desk I T. Simpkin - NLA 2500n' 9208260024 DR woeieADOCK PDR 00000457 [g'22.-

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Braidwood Station Units 1 and 2 l Auxiliary Building Vent Stack j

.- Wide Range Noble Gas Monitor Inoperable for Greater than 7 Days DRE.CLipilDu

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On August 7, 1992 at 1100 hours0.0127 days <br />0.306 hours <br />0.00182 weeks <br />4.1855e-4 months <br />, the Unit 2 Auxiliary Building Vent Stack Wide Range Noble Gas Msaltor, 2PR30J, was declared inoperable due to I its inability to pass a source check. Technical Specification 3.3.3.6 Limiting Condition for Operation Action (c) was enter (J for both units since Technical Specification 3.3.3.6 requires one on rable wide range noble gas

,nitor per Auxiliary Building Vent Stack.

Canse_nt.1he_lngpe r ability The cause.of the inoperability was determined to be the failure of the high voltage power supply.

Action _Taken Nuclear Work Request (NWR) A56228 was. initiated on August 7, 1992 to repair 2PR30J. After 1r.itial troubleshooting in the field, the high voltage power supply and detector for the 2PR30J were replaced, but the problem perolsted. Continued troubleshooting in the field indicated that the new detector was bad; however, there were no more detectors in stock. The equipment was taken to the Instrument Maintenance D7partment shop where continued troubleshooting determined that it was the new high voltage power supply that was bad. The high voltage power supply was replaced for the second time, and then the equipment performed satisfactorily. The original detector was reinstalled and the equipment continued to perform satisfactorily. The difficulty in identifying the failed component caused the repair to exceed the 7 day allowed outage time.

During the period of time, 2PR30J was inoperable, the Unit 2 Auxiliary Building Vent Stack flow was continuously monitored by the Unit 2 Auxiliary Dullding Vent Stack Effluent Monitor, 2PR28J.

Elann_and Schedule _CoLFentoI.in2_the Channel _to_Q2cIAble Status 2PR30J was restored to aperable status August 17, 1992 at 2130 hours0.0247 days <br />0.592 hours <br />0.00352 weeks <br />8.10465e-4 months <br />.

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