ML17291A978

Special Rept:On 950712,loose Part Detection Sys Channel 4 Failed Due to Electrical Noise During Daily Check.Channel 4 Will Remain Inoperable Until Next Forced or Scheduled Outage When Primary Containment de-inerted for Other Work

ML17291A978
Person / Time
Site:	Columbia
Issue date:	08/18/1995
From:	Parrish J WASHINGTON PUBLIC POWER SUPPLY SYSTEM
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
GO2-95-156, NUDOCS 9508250391
Download: ML17291A978 (3)

Text

PRIORITY 1~(ACCELERATED RZDS PROCESSING) 0 NOTES.REGULATORY INFORMATION DISTRIBUTION SYSTEM (RIDS)ACCESSION NBR:9508250391 DOC.DATE: 95/08/18 NOTARIZED:

NO DOCKET FACXL:50-397 WPPSS Nuclear Project, Unit 2, Washington Public Powe 05000397 p AUTH.NAME AUTHOR AFFILIATION PARRISH,J.V.

Washington Public Power Supply System RECXP.NAME RECIPIENT AFFILIATION Document Control Branch (Document Control Desk)1

SUBJECT:

Special rept:on 950712,failure of loose part detection sys channel.DISTRIBUTION CODE: IE22D COPIES RECEIVED:LTR ENCL SIZE: TITLE: 50.73/50.9 Licensee Event Report (LER), Incident Rpt, etc.RECIPIENT ID CODE/NAME PD4-2 PD INTERNAL: ACRS AEOD/SPD/RRAB NRR/DE/ECGB NRR/DE/EMEB NRR/DRCH/HHFB NRR/DRCH/HOLB NRR/DSSA/SPLB NRR/DSSA/SRXB RGN4 FILE 01 EXTERNAL: L ST LOBBY WARD NOAC MURPHY,G.A NRC PDR COPIES LTTR ENCL RECIPIENT ID CODE/NAME CLIFFORD,J AEOD S CENTE E NRR/DI S P/PI PB NRR/DRCH/HXCB 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 Y,i N NOTE TO ALL"RZDS" RECIPIENTS:

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

TO ELIMINATE YOUR NAME FROM DISTRIBUTION LISTS FOR DOCUMENTS YOU DON'T NEED!TOTAL NUMBER OF COPIES REQUIRED: LTTR 27 ENCL 27 WASHINGTON PUBLIC POWER SUPPLY SYSTEM PO.Box 968~3000 George Washington Way~Richland, Washington 99352-0968

~(509)372-5000 August 18, 1995 G02-95-156 Docket No, 50-397 U.S.Nuclear Regulatory Commission Attn: Document Control Desk Washington, D.C.20555 Gentlemen:

Subject:

WNP-2, OPERATING LICENSE NPF-21 SPECIAL REPORT: LOOSE PART DETECTION SYSTEM CHANNEL FAILURE This special report is submitted pursuant to the requirements of WNP-2 Technical Specification 3.3.7.10,"Loose-Part Detection System", which requires that the Loose Part Detection System (LPDS)be operable during Modes 1 and 2.The associated Action statement requires that a Special Report be submitted if one or more LPDS channels are inoperable for more than 30 days.One of the ten channels of the LPDS has been inoperable since July 12, 1995.The LPDS monitors the reactor pressure vessel (RPV)for internal loose parts per Regulatory Guide 1.133.Ten permanently mounted accelerometers are installed in various locations in the RPV and connected piping.A signal of twice normal background for any accelerometer will generate an alarm in the Main Control Room.Technical Specification 3.3.7.10 requires performance of a daily functional check of each of the ten channels to verify operability of the system.During the daily check on July 12, 1995, LPDS Channel Number 4 which monitors one of the Reactor Feedwater lines failed due to electrical"noise," requiring that the channel be declared inoperable.

The other nine channels were tested with satisfactory results.The investigation determined that the failure is intermittent and not in wiring or equipment accessible during reactor operation.

The probable cause is an intermittent fault in the equipment or cabling located inside Primary Containment.

9508250391 950818 PDR ADOCK 05000397 PDR t.'./~p g Page 2 SPECIAL REPORT: LOOSE PART DETECTION SYSTEM CHANNEL FAILURE Although the ability to detect loose parts in the affected feedwater line is impaired, the remaining nine channels are not impacted.Therefore, WNP-2 will continue to monitor these LPDS channels and perform the required surveillance tests.Channel Number 4 will remain inoperable until the next forced or scheduled outage when the Primary Containment is de-inerted for other work.Should LPDS Channel Number 4 repairs not be completed prior to completion of the next forced outage, repair efforts will continue when the Primary Containment is accessible during subsequent outages.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.V.Parris (Mail Drop 1023)Vice President, Nuclear Operations CJF/ml CC: LJ Callan-NRC RIV KE Perkins, Jr.-NRC RIV, Walnut Creek Field Office NS Reynolds-Winston&Strawn JW Clifford-NRC DL Williams-BPA/399 NRC Sr.Resident Inspector-927N