ML17291B098

Special Rept:On 951026,RB Effluent Monitoring Sys Inoperable for 72 H Due to Failure of Mid Range Stack Monitor.Cryostat Cooling Assemblies for Mid & High Range Stack Monitors Returned to Vendor for Refurbishment

ML17291B098
Person / Time
Site:	Columbia
Issue date:	11/08/1995
From:	PARRISH J V WASHINGTON PUBLIC POWER SUPPLY SYSTEM
To:	CALLAN L J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
References
GO2-95-238, NUDOCS 9511150163
Download: ML17291B098 (6)

Text

PRIORITY (ACCELERATED RIDS PROCESSING)

REGULATORY INFORMATION DISTRIBUTION SYSTEM (RIDS)ACCESSION NBR:9511150163 DOC.DATE: 95/11/08 NOTARIZED:

NO DOCKET g FACIL:50-397 WPPSS Nuclear Project, Unit 2, Washington Public Powe 05000397 p AUTH.NAME AUTHOR AFFILIA'ZION PARRISH,J.V.

Washington Public Power Supply System RECIP.NAME RECIPIENT AFFILIATION R CALLAN,L.J.

Region 4 (Post 820201)

SUBJECT:

Special rept:on 951026,RB effluent monitoring sys inoperable for 72 h due to failure of mid range stack monitor.Cryostat cooling assemblies for mid&high range stack monitors returned to vendor for refurbishment.

DISTRIBUTION CODE: IEZZD COPIES RECEIVED:LTR I ENCL SIZE: 3 TITLE: 50.73/50.9 Licensee Event Report (LER), Incident Rpt, etc.NOTES: RECIPIENT ID CODE/NAME PD4-2 PD INTERNAL: ACRS AEOD/SPD/RRAB NRR/DE/ECGB NRR/DE/EMEB NRR/DRCH/HICB NRR/DRCH/HQMB NRR/DSSA/SPLB NRR/DSSA/SRXB RGN4 FILE Ol EXTERNAL: L ST LOBBY WARD NOAC MURPHY,G.A NRC PDR COPIES LTTR ENCL RECIPIENT ID CODE/NAME CLIFFORD,J

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ILE CE/DE/EELB NRR/DRCH/HHFB NRR/DRCH/HOLB NRR/DRPM/PECB NRR/DS SA/S PS B/B RES/DSIR/EIB LITCO BRYCE,J H NOAC POORE,W.NUDOCS FULL TXT COPIES LTTR ENCL 0 N NOTE TO ALL"RIDS" RECIPIENTS:

PLEASE HELP US TO REDUCE WASTE!CONTACT THE DOCUMENT CONTROL DESK, ROOM OWFN 5D8 (415-2083)

TO ELIMINATE YOUR NAME FROM DISTRIBUTION LISTS FOR DOCUMENTS YOU DON'T NEED)TOTAL NUMBER OF COPIES REQUIRED: LTTR 27 ENCL 27 I Ej I WASHINGTON PUBLIC POWER SUPPLY SYSTEM i!O.Box 968~3000 George lVashington iVity~Richland, iVashington 99352.0968

~(509)372-5000 November 8, 1995 G02-95-238 Docket No.50-397 L.J.Callan Regional Administrator U.S.Nuclear Regulatory Commission Region IV'11 Ryan Plaza Drive, Suite 400 Arlington, TX 76011-8064

Dear Mr.Callan:

Subject;WNP-2, OPERATING LICENSE NPF-21 SPECIAL REPORT: REACTOR BUILDING EFFLUENT MONITORING SYSTEM This special r'eport is submitted pursuant to the requirements of WNP-2 Technical Specification Section 3.3.7.5,"Accident Monitoring Instrumentation," including Table 3:3.7.5-1, Item 31,"Reactor Building Effluent Monitoring System." Item 31 references Action 81 which states: "With the number of OPERABLE accident monitoring instrumentation channels less than required by the Minimum Channels OPERABLE requirement, either restore the inoperable channel(s) to OPERABLE status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, or:...prepare and submit a Special Report to the Commission pursuant to Specification 6.9.2 within 14 days following the event..." At 0935 hours0.0108 days <br />0.26 hours <br />0.00155 weeks <br />3.557675e-4 months <br /> on October 26, 1995 the Reactor Building Effluent Monitoring System was inoperable for 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> requiring the submittal of this special report.Event De cri tio The 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> Technical Specification Action Statement for the Reactor Building Effluent Radiation Monitoring System was entered at 0935 hours0.0108 days <br />0.26 hours <br />0.00155 weeks <br />3.557675e-4 months <br /> on October 23, 1995 when the mid range stack monitor (PRM-RE-1B) failed, as indicated by actuation of the Main Control Poom"Stack Monitor System Trouble" annunciator.

Subsequently, the high range stack monitor (PRM-RE-1C) failed.These stack monitors are part of the Reactor Building Effluent Monitoring System which is required to be in service during Operational Conditions 1, 2, and 3 in accordance with Technical Specification Table 3.3.7.5-1, Item 31.Both the mid range and high range stack monitors are required for the Reactor Building Effluent Radiation Monitoring System to be operable.I Z~>MM I)9511150163 951108 PDR ADOCK 05000397 8 PDR Page 2 SPECIAL REPORT: REACTOR BUILDING EFFLUENT MONITORING SYSTEM k The Backup Emergency Dose Projection System was verified operable as the preplanned alternate monitoring method in accordance with Table 3.3,7.5-1 Action 81 requirements and initiated at 1356 hours0.0157 days <br />0.377 hours <br />0.00224 weeks <br />5.15958e-4 months <br /> on October 23, 1995.A work request was issued to identify and correct the failures of the mid and high range stack monitors.e of the In era ilit This is another instance of recurring stack monitor failures in 1994 and 1995.An engineering investigation has been initiated to identify the underlying causes of the repeated failures.The investigation involves examination of vendor failure reports as well as consideration of the specific installation details at WNP-2.Inasmuch as the vendor failure report for the current failures will not be available until early December, a schedule for completion of the investigation cannot be finalized at this time.The status of the investigation and a schedule will be communicated to staff by December 11, 1995.WNP-2 will take such long-term action as determined appropriate from the engineering investigation.

In the short term, significant efforts are being made to restore the Reactor Building Effluent Radiation Monitoring System to operability.

Our initial investigation has determined the detector failures occurred because of degraded cooling.As a result, the cryostat cooling assemblies for both monitors were returned to the vendor for refurbishment.

em tatu The refurbished mid range cooling assembly will be available on-site for reinstallation on November 10, 1995.The reinstallation is a lengthy process that requires a controlled cooldown of the detector unit to cryogenic temperatures.

The entire process including installation, off-gassing, cooldown, and thermal stabilization takes approximately 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br />, at which time testing and calibration can be initiated.

Consequently, the unit is scheduled to be returned to service by November 16, 1995.The refurbished high range cooling assembly is expected to be available on-site for re-installation on November 17, 1995.Reinstallation and testing is scheduled to return the unit to service by November 23, 1995, which will restore the Reactor Building Effluent Radiation Monitoring System to operability.

A'I Page 3 SPECIAL REPORT: REACTOR BUILDING EFFLUENT MONITORING SYSTEM Should you have any questions or desire additional information regarding this matter, please call me or D.A.Swank at (509)377-4563.Sincerely, J,s'1 Vice, President, u CSFllam)rop 1023)lear Operations CC: Document Control Desk-NRC KE Perkins, Jr.-NRC RIV, Walnut Creek Field Office NS Reynolds-Winston 8c Strawn JW Clifford-NRC DL Williams-BPA/399 NRC Sr, Resident Inspector-927N