ML17305A868

Special Rept 3-SR-90-004:on 900509,radiation Monitoring Unit Inoperable Greater than 72 H.Caused by Inability to Maintain Detector Parameters to Meet Surveillance Testing Acceptance Criteria.Evaluation of New Detectors Being Performed

ML17305A868
Person / Time
Site:	Palo Verde
Issue date:	06/05/1990
From:	James M. Levine ARIZONA PUBLIC SERVICE CO. (FORMERLY ARIZONA NUCLEAR
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
192-00670-JML-T, 192-670-JML-T, 3-SR-90-004, 3-SR-90-4, NUDOCS 9006120212
Download: ML17305A868 (8)

Text

'g ACCELERATED . ISTRIBUTION DEMO NITRATION SYSTEM REGULATORY INFORMATION DISTRIBUTION SYSTEM (RIDS)

ACCESSION NBR:9006120212 DOC.DATE: 90/06/05 NOTARIZED: NO DOCKET FACIL:STN-50-530 Palo Verde Nuclear Station, Unit 3, Arizona Publi 05000530 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 3-SR-90-'04:on 900509,radiation monitoring unit inoperable greater than 72 h.

DISTRIBUTION CODE: IE22D COPIES RECEIVED:LTR ENCL SIZE:

TITLE: 50.73/50.9 Licensee Event Report (LER), ncident Rpt, etc.

NOTES:Standardized plant. 05000530 RECIPIENT COPIES RECIPIENT COPIES ID CODE/NAME LTTR ENCL ID CODE/NAME LTTR ENCL PD5 LA 1 1 PD5 PD 1 1 PETERSON,S. 1 1 CHAN,T 1 1 INTERNAL: ACNW 2 2 ACRS 2 2 AEOD/DOA 1 1 AEOD/DSP/TPAB 1 1 AEOD/ROAB/DSP 2 2 DEDRO 1 1 NRR/DET/ECMB 9H 1 1 NRR/DET/EMEB9H3 1 1 NRR/DLPQ/LHFBll 1 1 NRR/DLPQ/LPEB10 1 '

NRR/DOEA/OEAB11 1 1 NRR/DREP/PRPBll 2 2 NRR/DST/SELB 8D 1 1 NRR/DST/SICB 7E 1 1 N SPLB8D1 1 1 NRR/DST/SRXB 8E 1 1 02 1 1 RES/DSIR/EIB 1 1 RGN5 FILE 01 1 1 EXTERNAL: EG&G STUART,V.A 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 WASTETH CONTACT THE DOCUMENI'ONTROL DESK, ROOM P 1-37 (EXT. 20079) TO ELIMINATEYOUR NAME FROM DISTRIBUTION LISTS FOR DOCUMENTS YOU DON'T NEED!

TOTAL NUMBER OF COPIES REQUIRED: LTTR 38 ENCL 38

Arizona Public Service Company PALO VERDE NUCLEAR GEi IERATING STATION P 0 aOX52024 ~ P~OE>>IX. ~PIZO>>A55072.2cs~

192-00670-JML/TRB/KR June 5, 1990 U. S. Nuclear Regulatory Commission NRC Document Control Desk Washington, D.C. 20555

Dear Sirs:

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

Unit 3 Docket No. STN 50-530 (License No. NPF-74)

Special Report 3-SR-90-004 File'0-020-404 Attached please find Special Report 3-SR-90-004 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 a period 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, please contact T. R. Bradish, Compliance Manager, at (602) 393-2521.

Very truly yours, JML/TRB/KR/t1g Attachment cc: W. F. Conway (all w/attachment)

J. B. Martin T. L. Chan D. H. Coe A. C. Gehr A. H. Gutterman INPO Records Center 9QoAf2o2)2 PDR ADOCK LI5CII.I053O PDC

PALO VERDE NUCLEAR GENERATING STATION UNIT 3 Radiation Monitoring Unit Inoperable Greater Than 72 Hours License No. NPF-74

'ocket No. 50-530 Special Report 3-SR-90-004 Initial Conditions'n May 9, 1990 Palo Verde Unit 3 was in Mode 1 (POWER OPERATION) at approximately 100 percent power.

Descri tion of Event:

This Special Report is being submitted pursuant to Technical Specification 3.3.3.8 ACTION 42b and Technical Specification 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 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> period for returning the monitor to service was exceeded at approximately 0943 MST on May 9, e 1990.

On May 6, 1990 at approximately 0943 MST, Radiation Monitors RU-145 (Fuel Building Ventilation System Low Range Radioactive Effluent Monitor) and RU-146 were removed from service in accordance with an approved work document for scheduled 18 month calibration and surveillance. Radiation Monitors RU-145 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 limit. Since RU-145 and RU-146 work in tandem, RU-146 must be declared inoperable if RU-145 is out of service.

Pursuant to Technical Specification 3.3.3 ' ACTION 42.a, the Preplanned Alternate Sampling Program was initiated to monitor the Fuel Building Ventilation System.

During the performance of the calibration and surveillance, the RU-145 detector wou3.d, not pass the surveillance testing acceptance criteria.

Because the original equipment manufacturer (OEM) of that detector is no longer in business, the same detector provided by a second manufacturer was installed. During installation testing of this detector, it saturated when the check source was activated. Engineering is investigating the problem related to the new detectors being more sensitive to the check source than the OEM detectors.

Special Report 3-SR-90-004 Page 2 Cause of Event The cause of the event is that the detector's parameters (high voltage and counts per minute) could no longer be maintained to meet the surveillance testing acceptance criteria, which is an expected condition at the end of the detector's useful life.

Corrective Actions:

An engineering evaluation of the new detectors being more sensitive to the check source is being performed. Resolution of this issue and return to service of RU-145 and RU-146 are expected by June 15, 1990.