ML17306A222

Special Rept 1-SR-91-001-01:on 910111,fuel Bldg Ventilation Sys High Range Radioactive Gaseous Effluent Monitor Declared Inoperable for Period Greater than 72 H in Order to Perform Scheduled 18-month Surveillance Testing & Maint

ML17306A222
Person / Time
Site:	Palo Verde
Issue date:	10/10/1991
From:	James M. Levine ARIZONA PUBLIC SERVICE CO. (FORMERLY ARIZONA NUCLEAR
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
1-SR-91-001-01, 1-SR-91-1-1, NUDOCS 9110240244
Download: ML17306A222 (7)

Text

ACCELERATED DISTRIBUTION DEMONS~TION SYSTEM REGULATORY INFORMATION DISTRIBUTION SYSTEM (RIDS)ACCESSION NBR:9110240244 DOC~DATE: 91/10/10 NOTARIZED:

NO DOCKET FACIL:STN-50-528 Palo Verde Nuclear Station, Unit 1, Arizona Publi 05000528 AUTH.NAME AUTHOR AFFILIATION LEVINE,J.M.

Arizona Public Service Co.(formerly Arizona Nuclear Power RECIP.NAME RECIPIENT AFFILIATION Document Control Branch (Document Control Desk)

SUBJECT:

Special rept 1-SR-91-001-01:on 910111,fuel bldg ventilation sys high range radioactive gaseous effluent monitor declared inoperable for period greater than 72 h.Inoperable in order to perform scheduled 18-month surveillance testing&maint.DISTRIBUTION CODE: IE22D COPIES RECEIVED:LTR i ENCL L SIZE: TITLE: 50.73/50.9 Licensee Event Report (LER), Incident Rpt, etc.R D NOTES:STANDARDIZED PLANT RECIPIENT ID CODE/NAME PD5 LA TRAMMELL, C INTERNAL: ACNW AEOD/DOA AEOD/ROAB/DS P NRR/DET/EMEB 7E NRR/DLPQ/LPEB10 NRR/DREP/PRPB11 NRR/DST/SICB8H3 NRR/DST/SRXB 8E RES/DSIR/EIB EXTERNAL: EG&G BRYCE,J.H NRC PDR NSIC POORE,W.NOTES: COPIES LTTR ENCL 1 1 1 1 2 2 1 1 2 2 1 1 1 1 2 2 1 1 1 1 1 1 3 3 1 1 1 1 1 1 RECIPIENT ID CODE/NAME PD5 PD THOMPSON,M ACRS AEOD/DSP/TPAB NRR/DET/ECMB 9H NRR/DLPQ/LHFB10 NRR/DOEA/OEAB NRR/DST/SELB 8D NRR/D~S/SP.-X 8D1 RE--0.RGN5 FILE 01 L ST LOBBY WARD NSIC MURPHY,G.A NUDOCS FULL TXT COPIES LTTR ENCL 1 1 1 1 2 2 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 05000528 A D D p g 5'yR.IP~dg D NOTE TO ALL"RIDS" RECIPIENTS:

A D D PLEASE HELP US TO REDUCE WASTE!CONTACT THE DOCUMENT CONTROL DESK, ROOM P 1-37 (EXT.20079)TO ELIMINATE YOUR NAME FROM DISTRIBUTION LISTS FOR DOCUMENTS YOU DON'T NEED!TOTAL NUMBER OF COPIES REQUIRED: LTTR 35 ENCL 35 M

JAMES M.LEVINE VICE PRESIDENT NUCLEAR PRODUCTION Arizona Public Service Company PALO VERDE NUCLEAR GENERATING STATION P.O.BOX 52034~PHOENIX.ARIZONA 85072-2034 192-00745-QML/TRB/KR October 10, 1991 U.ST Nuclear Regulatory Commission Attention:

Document Control Desk Mail Station Pl-37 Washington, D.C.20555

Dear Sirs:

Sub]ect: Palo Verde Nuclear Generating Station (PVNGS)Unit 1 Docket No.STN 50-528 (License No.NPF-41)Special Report 1-SR-91-001-01 File'1-020-404 Attached please find Supplement 1 to Special Report 1-SR-91-001 prepared and submitted pursuant to Technical Specifications 3.3.3.8 ACTION 42(b)and 6.9.2.This report discusses a radiation monitor being inoperable for greater than 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.This supplement is being provided to reformat the information provided and to clarify the circumstances which contributed to the monitor being out of service.We are forwarding a copy of the Special Report to the Regional Administrator of the Region V office.If you have any questions, please contact DE A.Johnson, Compliance Supervisor, at (602)393-3703.Very truly yours, JML/TRB/KR/nk Attachment cc: W.F, Conway J.B.Martin D.H.Coe 9'110240244 911010 PDR ADOCK 05000 28 PDR (all with attachment) g)0 0P I (gal'~

PALO VERDE NUCLEAR GENERATING STATION UNIT 1 Radiation Monitoring Unit Inoperable Greater Than 72 Hours License No.NPF-41 Docket No.50-528 Special Report 1-SR-91-001-01 n tial Co d t o s: This Special Report is being submitted pursuant to Technical Specification (TS)3.3.3.8 ACTION 42(b)and TS 6.9.2 to report an event in which the Fuel Building Ventilation System High Range Radioactive Gaseous Effluent Monitor (RU-146)was inoperable for a period greater than 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.The 72-hour period for returning the monitor to service was exceeded at approximately 1355 MST on January ll, 1991.On January ll, 1991, Palo Verde Unit 1 was in Mode 1 (POWER OPERATION) at approximately 100 percent power.Back rou d I formation:

Radiation Monitors RU-145 (Fuel Building Ventilation System Low Range Radioactive Effluent Monitor)and RU-146 monitor the Fuel Building Ventilation Exhaust for release of radioactivity due to a fuel handling accident.Radiation Monitors RU-145 and RU-146 work as a pair with RU-145 being the low range monitor for normal radioactive gaseous effluents and RU-146 being the high range monitor for post-accident radioactive gaseous effluents.

Normal configuration consists of RU-145 operating and RU-146 in standby.When RU-145 reaches a predetermined setpoint, RU-146 starts and RU-145 goes to standby.RU-145 initiates a Fuel Building Essential Ventilation Actuation Signal (FBEVAS)when the activity exceeds a predetermined setpoint, RU-146 starts and RU-145 goes to standby.RU-145 initiates a Fuel Building Essential Ventilation Actuation Signal (FBEVAS)when the activity exceeds a predetermined limit.Since RU-145 and RU-146 work in tandem, RU-146 must be declared inoperable if RU-145 is out of service.Actions Take On January 8, 1991, at approximately 1355 MST, Radiation Monitors RU-145 and RU-146 were removed from service in accordance with an approved work document for scheduled 18-month calibration and surveillance tests (ST).Alternate sampling was initiated in accordance with the Preplanned Alternate Sampling Program to monitor the Fuel Building Ventilation System fulfilling TS 3.3.3.8 ACTIONS 36, 37, 40 and 42, as applicable.

'ased on Palo Verde experience, the average performance interval for the high and low range effluent monitor 18-month ST is approximately 120 hours0.00139 days <br />0.0333 hours <br />1.984127e-4 weeks <br />4.566e-5 months <br />.Additionally, during the performance of the calibration and surveillance, the RU-145 detector would not pass the surveillance testing acceptance criteria due to a faulty low voltage power supply.While waiting for a replacement power supply, testing began on RU-146.The power supply failure has been addressed in previous root cause of failure (RCF)evaluations.

Based on the RCF, when the power supply malfunction is detected, an upgraded replacement

.0 f 1 1 I i f NRC Document Control Desk Page 2 Special Report 1-SR-91-001-01 power supply is being installed in the monitors.Additional corrective maintenance was also performed to replace a hexadecimal display board for RU-145 which was discovered to be functioning improperly.

Corrective maintenance and the 18-month STs were completed and the monitors were returned to service at approximately 1250 MST on January 13, 1991.Cause of t e no erabilit RU-146 was inoperable in order to perform scheduled 18-month surveillance testing and corrective maintenance, as described above.lans and Schedule for Restorin the S stem to Service: Radiation monitors RU-145 and RU-146 were returned to an OPERABLE status following satisfactory completion of the STs at approximately 1250 MST on January 13, 1991.The monitors were out of service approximately 5 days.