ML20135F332

Special Rept:On 970303,Braidwood Auxiliary Bldg Vent Stack Wide Range Gas Monitor Was Inoperable for Greater than Seven Days.Caused by Removing Monitoring from Operation to Perform 18-month Channel Calibr.Calibr Was Completed

ML20135F332
Person / Time
Site:	Braidwood
Issue date:	03/04/1997
From:	COMMONWEALTH EDISON CO.
To:
Shared Package
ML20135F328	List: ML20135F325 ML20135F332
References
NUDOCS 9703120071
Download: ML20135F332 (2)

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ENCLOSURE BRAIDWOOD AUXILIARY BUILDING VENT STACK WIDE RANGE GAS MONITOR INOPERABLE FOR GREATER THAN SEVEN DAYS REPORT DESCRIPTION OF THE EVENT:

1 The Unit 1 Process Radiation Monitor IPR 301, Auxiliary Building Vent Stack Wide Range  !

Gas Monitor, was taken out of service on February 24,1997 for planned channel calibration.

Procedure BwlS 3.3.6-211, " Surveillance Calibration of Aux Building Vent Stack Wide d

Range Gas Monitor" was used to perform the 18-month channel calibration of the 1PR30J. l The appropriate Technical Specification Action Statements were entered and complied with. l

!.t 0400 hours0.00463 days <br />0.111 hours <br />6.613757e-4 weeks <br />1.522e-4 months <br /> on March 4,1997 the calibmtion procedure was satisfactorily completed and the monitor was returned to operable status. However, the 7-day LCO expired on March 3, l

1997 at 0759 hours0.00878 days <br />0.211 hours <br />0.00125 weeks <br />2.887995e-4 months <br />. This report is being submitted in accordance with Tecimical Specification 3.3.3.6.c, which stipulates that with the number of operable channels for the Auxiliary Building Vent Stack Wide Range Noble Gas Monitor less than the minimum channel operable requirement, restore the inoperable channel to operable status within 7 days or prepare and submit a Special Report to the Conunission pursuant to specification 6.9.2 within 14 days that provides action taken, cause of the inoperability and plans and schedule restoring the channel j to operable status. ]

CAUSE OF THE INOPERABILITY:

The cause of the inoperability was removing the monitoring from operation to perform as required, a regularly scheduled 18-month channel cahbration. The cause for the completion of the calibration exceeding seven days was due to the following:

1. The sample pump for the IPR 30] radiation monitor was not meeting its flow requirements for the calibration. A replacement pump was on site but was awaiting a revised evaluation from the central storage facility in Bolingbrook. This stores item number was not qualified for use on the IPR 30J radia't ion monitor. Substantial time was lost in evaluating the pump for us in the IPR 30J.

2. Several days into the calibration, the input / Output (1/0) card failed A new 1/O card was installed and the calibration of the radiation monitor was continued.

Approximately 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> later, the new I/O card was found to be causing errors in calibration. It was determined that the new I/O board purchased from stores was locking up and was not performing to its acceptance criteria. Another card was installed, and the instrument maintenance department continued with the surveillance.

ACTIONS TAKEN:

After being taken out of service for approximately 7 days and 20 hours2.314815e-4 days <br />0.00556 hours <br />3.306878e-5 weeks <br />7.61e-6 months <br />, the scheduled calibration was satisfactorily completed and the monitor was retumed to operable status.

9703120071 970304 PDR ADOCK 05000456.

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Page 2 - Enclosure March 4,1997 PLANS AND SCHEDULE FOR RESTORING THE CHANNEL TO OPERABLE I STATUS:

1 The Auxiliary Building Vent Stack Wide Range Gas Monitor,1PR30J. was returned to operable status on March 4,1997 at 0400 hours0.00463 days <br />0.111 hours <br />6.613757e-4 weeks <br />1.522e-4 months <br />. The monitor has performed satisfactorily since being returned to service.

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