ML20118B536

Special Rept:On 920913,auxiliary Bldg Vent Stack wide-range Gas Monitor Declared Inoperable.Caused by Need to Perform Instrument Maint Surveillance Procedure.Nuclear Work Request Generated to Replace Failed Printed Circuit Board

ML20118B536
Person / Time
Site:	Braidwood
Issue date:	09/25/1992
From:	Kofron K COMMONWEALTH EDISON CO.
To:	Davis A NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
References
BW-92-0491, BW-92-491, NUDOCS 9210050041
Download: ML20118B536 (2)

Text

, - - - , . . +_. .- - . ._

i* - *- Commonwealth Edison C . Braidwood Nuclear Power Station Route C, Box 84

-l V O Braceville, Illinois 60407 Talephone 815/458-2801..

September 25,1992.

BW/92 0491 prcmr g, ,

y pw \

- Mr. A. Bert Davis R lonal Administrator Offf / I V "7 F

Y;-

l U. . Nuclear Regulatory Commission Re ion Ill N.y Q a -pld--j 79 Roosevelt Road rarg -

Glen Ellyn, IL 60137

Subject:

Braidwood Sta' ion Unit 2 Auxiliary Building Vent Stack Wide Rangt Noble Gas Monitor inoperability NRC Docket No. 457

Reference:

(a) NUREG-1276, Technical Specifications

Dear M.. Davis:

Braidwood Station Technical Specification 3.3.3.6 Act'on (c) requires that with less than the minimum number of auxilirry building vent stack wide range noble gas monitors operable for more than 7 days a Special Report shall be prepared and submitlea to the Commission within 14 days pursuant to Specification 6.9.2 that provides the actions taken, cause of the inoperability, and plans and schedule for restoring the channel (s) to operable status. Pursuant to these Specifications, the enclosure provides a report regarding the inoperability of the Unit 1 Auxiliary Building Vent Stack Wide Ranga Noble Gas Monitor,1PR30J, initiated September 13,1992 at 0809 hours0.00936 days <br />0.225 hours <br />0.00134 weeks <br />3.078245e-4 months <br />. The inoperability of 1PR30J affects Unit 2 r cident monitoring cc.pabilities.

Please direct any questions regarding this submittal to Harry Pontious.

Braidwood Station Licensing Coordinator, extension 2511.

Very truly.yours,

)s Ly K. L. H afron -

St.-Mon Manager Braidwood Nuclear' Station KLK/HDP/mko 633/ZD85G ,

Enclosure cc: R. Pulsifer - NRR B. Clayton - Rlli l Resident inspector - Braldwood //p NRC Document Control Desk T. Simpkin - NLA '}

10 0? '" 92100S0041 920925 ADOCK0500$7 ;e $

{DR

4 Braidwood Station Unit 2 Auxiliary Building Vent Stack Wide Range Noble Gas Monitor inoperable for Greater Than 7 Days Description On September 13,1992 at 0809 hours0.00936 days <br />0.225 hours <br />0.00134 weeks <br />3.078245e-4 months <br />, the Unit 1 Auxiliary Building Vent Stack Wide Range Noble Gas Monitor,1PR30J, was declared inoperable and removed from service for the performance of Braidwood Instrument Maintenance Surveillance Procedure (BwlS) 3.3.6-211, Surveillance Calibration of Aux Building Wide Range Gas Radiat:on Monitor. BwlS 3.3.6 211 is performed to satisfy the 18 month channel calibration requiremont of Technical Specification Surveillance Requirement (TSSR) 4.3.3.6, Table 4.3-7, Instrument 18. Technical Specification 3.3.3.6 Limiting Condition for Operation Action (c) was entered for Unit 2 since Technical Specification 3.3.3.6 requires one operable wide range noble gas monitor per Auxiliary Building Vent Stack, Gause_oLibelnoputability The cause of the inoperability of 1PR30J was removing the monitor from service in order to perform BwlS 3.3.6-211 Actioulaken During the performance of BwlS 3.3.6-211, the input / output (1/0) printed circuit board failed. A Nuclear Work Request (NWR) was generated to replace the failed I/O printed circuit board. The calibration was halted until the I/O printed circuit board was replaced. Once the I/O printed cccuit board was replaced, those sections of the calibration already completed were perfo med again in order to demonstrate the operability of the new l/O printed circuit board. .\s the calibration of 1PR30J continued, it was discovered that the grab sample timers were out of calibration. An additional NWR has been generated to recalibrate the grab sample timers. Calibration of 1PR30J is on hold pending completion of that work which is currently in progress.

Elari andEched ule_fotBe_ storing .iberhannettoDperable3tatus Following recalibration of the grab sample timers, the calibration of 1PR30J will be resumed. It was expected that the calibration of 1PR30J will be completed and the monitor returned to service no later than October 9,1992.

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