ML17303A483

Special Rept 2-SR-87-020:on 870619,inoperable Containment Bldg Atmosphere Pressure Monitor RU-1 Exceeded 72 H Limit. Caused by Need to Replace Channel 2 Detector.Radiation Monitoring Unit Task Force Established to Review Occurrence

ML17303A483
Person / Time
Site:	Palo Verde
Issue date:	07/10/1987
From:	Haynes J ARIZONA PUBLIC SERVICE CO. (FORMERLY ARIZONA NUCLEAR
To:	NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM)
References
192-00238-JGH-T, 192-238-JGH-T, 2-SR-87-020, 2-SR-87-20, NUDOCS 8707200019
Download: ML17303A483 (4)

Text

REGULA ~. Y INFORMATION DISTR IBUTIOI YSTEM (RIDS)

ACCESSION NBR: 870720001.9 DOC. DATE: 87/07/10 NOTARIZED: NO DOCKET 0 FACIL: STN-50-529 Palo Verde Nuclear Stations Unit 2i Arizona Publi 05000529 AUTH. NAME AUTHOR AFFILIATION HAYNES> J. G, Arizona Nuclear Poeer Prospect (formerly Arizona Public Serv REC IP. NAME RECIPIENT AFFILIATION Document Control Branch (Document Control Desk)

SUBJECT:

Special Rept 2-SR-87-020: on 870616'ow channel reading discovered on containment bldg atmosphere process monitor RU-1 during performance of 18-month calibr test. Caused bg light leak around seal ring holder. Detector replaced.

DISTRIBUTION CODE: IE22D COPIES RECEIVED: LTR ~ ENCL TITLE: 50. 73 Licensee Event Report (LER)i Incident Rpti

+etc.SIZE:

NOTES: Standardized plant. M. Davisi NRR: iCg. 05000529 REC IP IENT. COPIES RECIPIENT. COPIES ID CODE/NAME LTTR ENCL ID CODE/NAME LTTR ENCL PD5 LA 1 1 PD5 PD 1 1 LICITRA> E 1 DAVIS' 1 INTERNAL: ACRS MICHELSON 1 1 ACRS MOELLER 2 AEOD/DOA 1 1 *EOD/DSP/ROAB 2 2 AEOD/DSP/TP*B 1 1 DEDRO 1 1 NRR/DEST/*DE 1 0 NRR/DEST/ADS '0 NRR/DEST/CEB 1 1 NRR/DEST/ELB 1 NRR/DEBT/ICSB 1 1 NRR/DEST/MEB i 1 NRR/DEST/MTB 1 1 NRR/DEST/PSB 1 1 NRR/DEST/RSB 1 NRR/DEST/SGB 1 NRR/DLPQ/HFB 1 1 NRR/DLPG/GAB 1 NRR/DOEA/EAB 1 1 NRR/DREP/RAB 1 1 NRR/DREP/RPB NRR/PM*S/ ILRB 1 1 NRR/PMAS/PTSB 1 1 02 1 1 RES DEPY GI 1 RES TELFORDi J 1 1 RES/DE/EIB 1 1 RGN5 FILE 01 1 1 EXTERNAL: EGSG GROHi M 5 5 H ST LOBBY WARD 1 1 LPDR 1 1 NRC PDR 1 .1 NSIC HARRIS' 1 1 NSIC MAYSa G 1 NOTES: 1 1 TOTAL NUMBER OF COPIES REQUIRED: LTTR 46 ENCL 44

Arizona Nuclear Power Project P.o. BOX 52034 ~ PHOENIX. ARIZONA 85072-2034 192-00238-JGH-TRB/ESP July 10, 19S7 U.S. Nuclear Regulatory Commission NRC Document Control Desk Washington, D.C. 20555

Subject:

Palo Verde Nuclear Generating Station (PVNGS)

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

Special Report 2-SR-87-020 File: 87-020-404

Dear Sirs:

Attached please find a Special Report 2-SR-87-020 prepared and submitted pursuant to Technical Specifications 3.1.1.1 and 6.9.2. This report discusses a radiation monitoring unit inoperable f"r greater than 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.

Tf you have any questions, please contact T. R. Bradish, Compliance Supervisor at (602) 393-5000, Ext. 6936.

Very tru y yours, J. G. Haynes Vice President Nuclear Production JGH/TRB/ESP/cld Attachment cc: 0. M. DeMichele (all w/a)

E. E. Van Brunt, Jr.

J. B. Martin R. P. Zimmerman R. C. Sorenson E. A. Licitra A. C. Gehr INPO Records Center 87072000i9 870710 PDR ADOCK 05000529 S PDR

PALO VERDE NUCLEAR GENERATING STATION RADIATION MONITOR INOPERABLE FOR GREATER THAN 72 HOURS License No. NPF-51 Docket No. STN 50-529 Special Report No. 2-SR-87-020 This Special Report is being submitted pursuant to Technical Specification (T.S.) 3.3.3.1 ACTION 27 and T.S. 6.9.2 to report an event in which the Containment Building Atmosphere Process Monitor (RU-1) was 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 operability was exceeded at approximately 1127 MST on June 19, 1987. Pursuant to T,.S. 3.3.3.1 ACTION 27b the moveable air monitor (RU-53) was placed in line.

At approximately 1127 MST on June 16, 1987, Palo Verde Unit 2 was in Mode 1 (POMER OPERATION) when RU-1 was taken out of service to allow the performance of the scheduled 18 month calibration test.

During calibration testing the detectors are removed from the monitor and placed into a Calibration fixture. At that time it was discovered that Channel 2 was reading lower than acceptable by the Surveillance Test. A work authorizing document was issued to troubleshoot the monitor. Troubleshooting revealed that the detector for Channel 2 could not be adjusted to specifications. As an immediate corrective action, the detector was replaced.

Additionally, during placement of the Channel 3 detector into the calibration fixture high background readings were observed. A work authorizing document was issued to determine the cause of increased readings when exposed to light.

Troubleshooting determined that light was leaking around the seal ring holder; no evidence of damage or wear was discovered. Since the tube is located in an environment devoid of light, and the readings prior to testing were in calibration this channel was considered operable. However, as a prudent action, the detector was replaced.

Upon completion of the work order and appropriate surveillance test, RU-1 was restored to an operable status on July 3, 1987 at 0839. The monitor was out of service for 17 days, 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> and 46 minutes.

A Radiation Monitoring Unit task force has been, established to address the root cause of detector failures and an expedient method to restore the monitors to operablility within the required time.

i,