ML20207L819

Special Rept:On 880913,high Range Noble Gas Effluent Monitor Detector Failed Due to Water Intrusion Into Detector Well. on 880915,spare Detector Installed & Tested,Resulting in Discovery That Source Check Circuit Not Operating Properly

ML20207L819
Person / Time
Site:	Big Rock Point File:Consumers Energy icon.png
Issue date:	10/12/1988
From:	Marbaugh K CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.)
To:	NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM)
References
NUDOCS 8810170477
Download: ML20207L819 (3)

Text

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Consumers power pewsmus nioGNEAN5 PROGRESE General officoe: 1945 West Parnell Road, Jock.on, MI 49201 . (517) 788 0550 ,

October 12, 1980 i

l

! Nuclear Regulatory Commission Document Control Desk  !

Washington, DC 20555 I f

i DOCKET 50-155 - LICENSE DPR BIG ROCK POINT PLANT -

I '

TECHNICAL SPECIFICATION 13.1.1 SPECIAL REPORT - RADI0 ACTIVE EFFLUENT l

MONITORING INSTRUMENTATION OPERABILITY AND SURVEILLANCE REQUIREMENTS l 1

Consumers Power Company's Big Rock Point Technical Specificaticn 13.1.1 l requires that the Hi Range Noble Gas Effluent Monitor be in service at all times. Sheuld the channel fail the following actions are required:

i With the channel inoperable, initiate the preplanned alternate inethod of monitoring the appropriate parameter (s), within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, and:

1. either restore the inoperable channel (s) to Operable status within 7 days of the event, or

, 2. prepare and submit a Special Report to the Commission pursuant to i Specification 6.9.3 within 30 days following the event outlining the 4

action taken, the esuse of the inoperability and the plans and

)

sc.hedule for restoring the system to operable status.

l In accordance with this requitement, a Special Report is attached explaining

.i an incident ir. which the Hi Range Noble Gas Effluent Monitor was inoperable in excess of 7 days.

4 l

XKenneth L dE Marbaughe da a Gg<

. Plant Licensing Engineer 1

CC Adminictrator, Region III. NRC l NRC Resident ?.nspector - Big Rock Point '

Attachment  ;

l OC1080-0167-NLO2 8810170477 GG1012

, PDR ADOCK 050001'55

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-_ _ - _ - _ . - - -_--__-._m.

1 l ATTACHMENT Consumers Power Company Big Rock Point Plant ,

Docket 50-155 SPECIAL REPORT PER TECHNICAL SPECIFICATION 13.1.1 October 12, 1988 1

i 1 Page f OC1088-0167-NLO2

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BIG ROCK POINT PLANT SPECIAL REPORT PER TECHNICAL SPECIFICATION 13.1.1 Description of Occurrence on September 13, 1988 at 2000 hours0.0231 days <br />0.556 hours <br />0.00331 weeks <br />7.61e-4 months <br />, the Hi Range Noble Gas Effluent Monitor detector failed due to water intrusion into the detector well. Immediate actions were taken to provide an alternate method of monitoring the effluent pathway as required by the Technical Specification and was operable on September 14 at 1420 hours0.0164 days <br />0.394 hours <br />0.00235 weeks <br />5.4031e-4 months <br />, well within the 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> requirement. i on September 15, 1988 the spare detector was installed and tested when it was discovered that although the replacement detector was functional, the source check circuit was not operating correctly. After extensive troubleshooting efforts, the vendor, Victoreen Corporation, was contacted for assistance.

On September 20, 1988 Victoreen identified that the replacement detector was an upgrade model from the detector originally installed in tl'e system and a modification consisting of minor witing changes to the check source circuitry were required to permit the source check circuit to function properly.

On September 23, 1988 Victoreen Corporation supplied the necessary drawings and instructions to complete the wiring changes and following completion of the modification and calibration, the monitor was returned to service.

On September 26, 1988 following review of the modification work activity and required testing per Plant Administrative Procedures, the system was declared operable at 1310 hours0.0152 days <br />0.364 hours <br />0.00217 weeks <br />4.98455e-4 months <br />.

Cause The Radioactive Cas Effluent Monitoring System was installed at Big Fcck Point ,

in 1982. Following installation, spare parts were obtained from Victoreen and placed into stock. Apparently, betwean initial delivery of the system and spare parts procurement, Victoreen modified the design of the detector to improve performance. Ilowever, Victoreen did not identify nor supply the i

drawings which would have indicsted that a system eodification was necessary

, prior to our effortn in using the in-stock spare. Since the need for the system redification was not discovered untti after the failure additional time was required to receive the information and process the design change which extended the out-of-service period beyond seven days.

Action To Prevent Recurrence The failed detector has been returned to Victoreen Corporation to be repaired and modified to the new design. This will pernit preept installation should another detector fail without wiring changes. If the failed detector cannot be repaired, a new detector will be shipped in its place to be used as a upare.

OC1088-0167-NLO2