ML17305A372

Special Rept 2-SR-89-007:on 891002,72 H Limit for Returning Fuel Bldg Ventilation Sys low-range Radioactive Gaseous Effluent Monitor & high-range Monitor to Operable Status Exceeded.Cause Under Investigation

ML17305A372
Person / Time
Site:	Palo Verde
Issue date:	10/31/1989
From:	James M. Levine ARIZONA PUBLIC SERVICE CO. (FORMERLY ARIZONA NUCLEAR
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
192-00545-JML-T, 192-545-JML-T, 2-SR-89-007, 2-SR-89-7, NUDOCS 8911090070
Download: ML17305A372 (6)

Text

ACCELERATED STRIBUTION DEMON~ $A,TION SYSTEM REGULATORY INFORMATION DISTRIBUTION SYSTEM (RIDS)

ACCESSION NBR:8911090070 DOC.DATE: 89/10/31 NOTARIZED: NO FACIL:STN-50-529 Palo Verde Nuclear Station, Unit 2, Arizona Publi DOCKET 05000529 AUTH. NAME AUTHOR AFFILIATION LEVINEiJ.M. Arizona Public Service Co. (formerly Arizona Nuclear Power RECIP.NAME RECIPIENT AFFILIATION Document Control Branch (Document Control Desk)

SUBJECT:

Special Rept 2-SR-89-007:on 891002,72 h limit for returning monitors to operable status exceeded.

DISTRIBUTION CODE: IE22D COPIES RECEIVED:LTR A ENCL TITLE: 50.73/50.9 Licensee Event Report (LER), Incident Rpt, etc.

SIZE:

NOTES:Standardized plant. 05000529 RECIPIENT COPIES RECIPIENT COPIES ID CODE/NAME LTTR ENCL ID CODE/NAME LTTR ENCL PD5 LA 1 1 PD5 PD 1 1 CHAN,T 1 1 DAVIS,M. 1 1 INTERNAL: ACRS MICHELSON 1 1 ACRS MOELLER 2 2 ACRS WYLIE 1 1 AEOD/DOA 1 1 AEOD/DSP/TPAB 1 1 AEOD/ROAB/DSP 2 2 DEDRO 1 1 NRR/DEST/ESB 8D 1 1 NRR/DEST/ICSB 7 1 1 NRR/DEST/MEB 9H 1 1 NRR/DEST/MTB 9H 1 - 1 NRR/DEST/PSB 8D 1 1 NRR/DEST/RS B 8E 1 1 NRR/DEST/SGB 8D 1 1 NRR/DLPQ/HFB 10 1 1, NRR/DLPQ/PEB 10 1 1 NRR/DOEA/EAB 1 1 1 1 NRR/DREP RPB 10 2 2 NUDOCS-ABSTRACT 1 1 1 1 RES/DSIR/EIB j.'

1 1 EXTERNAL: EG&G WILLIAMS,S 4 4 L ST LOBBY WARD 1 1 LPDR 1 1 NRC PDR 1 1 NSIC MAYS,G 1 . 1 NSIC MURPHY,G.A 1 1 NUDOCS FULL TXT 1 1 NOTES: 1 1 NOTE TO ALL "RIDS" RECIPIENTS:

PLEASE HELP US TO REDUCE WASTE! CONTACT THE DOCUMENT CONTROL DESK, ROOM Pl-37 (FXT.?Nl7@ TO ELIMINATEYOUR NAME FROM DISTRIBUTION LISTS FOR DOCUi!ENTS YOU DON'T NEED!

TOTAL NUMBER OF COPIES REQUIRED: LTTR 40 ENCL 40

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Arizona Public Service Company PALO VERDE NUCLEAR GENERATING STATION "P 0 BOX 52034 ~ PHOENIX ARIZONA 85072.2034 192-00545-JML/TOS/RKR October 31, 1989 U. S. Nuc'ear Regulatory Commission NRC Document Control Desk Washington, D.C. 20555

Dear Sirs:

Sub j ect: Palo Verde Nuclear Generating Station (PVNGS)

Unit 2 Docket No. STN 50-529 (License No. NPF-51)

Special Report 2-SR-89-007 File: 89-020-404 Attached please find Special Report 2-SR-89-007 prepared and submitted pursuant to Technical Specification 3.3.3.8 ACTION 42.b and 6.9.2. This report discusses a radiation monitor inoperable for greater than 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.

If you have any questions on this matter, please contact Mr. Timothy Shriver, Compliance Manager at (602) 393-2521.

Very truly yours, J. M. evine ice President Nuclear Production JML/TDS/RKR/kj Attachment cc: W. F. Conway (w/attachment)

J. B. Martin T. J. Polich M. J. Davis A. C. Gehr INPO Records Center

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PALO VERDE NUCLEAR GENERATING STATION 0

Radiation Monitoring Unit Inoperable for Greater Than 72 Hours License No.

NPF-51'ocket No. STN 50-529 Special Report 2-SR-89-007 This Special Report is submitted in accordance with Technical Specifications 3.3.3.8 ACTION 42.b and 6.9.2 to report an event in which the Fuel Building Ventilation System Low Range Radioactive Gaseous Effluent Monitor (RU-145) and High Range Radioactive Gaseous Effluent Monitor (RU-146) were inoperable for greater than 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. The 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> limit for returning the monitors to an operable status was exceeded at approximately 0305 MST on October 2, 1989.

At approximately 0305 MST on September 29, 1989 Palo Verde Unit 2 was in Mode 1 (POWER OPERATION) at approximately 100 percent power when the Fuel Building Ventilation System. Radioactive Gaseous Effluent Monitors (RU-145 'and RU-146) were declared inoperable- due to frequent low flow alarms on the radiation monitor sample flow. The problem was discovered by control room personnel. Pursuant to Technical Specification 3.3.3.8 ACTION 42.a the Preplanned Alternate Sampling Program was initiated to monitor the appropriate parameters.

Monitors RU-145 and RU-146 work as a pair with RU-145 being the low range monitor and RU-146 being the high range monitor'. Normal configuration consists of RU-145 operating and RU-146 in standby. When RU-145 reaches a predetermined level, RU-146 starts and RU-145 goes to standby. Since RU-145 is inoperable, RU-146 must also be declared inoperable.

An authorized work document was issued to troubleshoot and rework or replace components as necessary to correct the low flow alarms. The initial investigation revealed that a majority of the low flow alarms were a result of actual low flow conditions due to the low flow limit switch drifting from its desired position. The limit switch was readjusted in accordance with an approved procedure. The cause of the remaining low flow alarms is still under investigation. Following appropriate corrective action, the Radiation Monitors RU-145 and RU-146 will be returned to an operable status. The plans and schedule for returning the monitor to service has not been determined since the cause and corrective actions have not been determined.

The low flow alarms for the radiation monitor (RU-145) sample flow are being investigated in accordance with an approved work document. The investigation is being conducted to determine and correct the malfunction. The results of this investigation will be reported in a supple'ment to this report which is expected to be submitted by February 1, 1990.

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