ML17306A298

Special Rept 2-SR-91-002:on 911107,fuel Bldg Ventilation Sys high-range Radioactive Gaseous Effluent Monitor Inoperable for More than 72 H.Caused by Power Supply Deenergized for Scheduled Maint.Monitor Returned to Svc on 911114

ML17306A298
Person / Time
Site:	Palo Verde
Issue date:	12/05/1991
From:	James M. Levine ARIZONA PUBLIC SERVICE CO. (FORMERLY ARIZONA NUCLEAR
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
192-00760-JML-T, 192-760-JML-T, 2-SR-91-002, 2-SR-91-2, NUDOCS 9112110106
Download: ML17306A298 (7)

Text

ACCELERATED DISTRIBUTION DEMONSTRATION SYSTEM REGULATORY INFORMATION DISTRIBUTION SYSTEM (RIDS)

ACCESSION NBR:9112110106 DOC-DATE: 91/12/05 NOTARIZED: NO DOCKET FACIL:STN-50-529 Palo Verde Nuclear Station, Unit 2, Arizona Publi 05000529 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 2-SR-91-002:on 911107,fuel bldg ventilation sys high-range radioactive gaseous effluent monitor inoperable for more than 72 h.Caused by power supply deenergized for scheduled maint.Monitor returned to svc on 911114. D DISTRIBUTION CODE: IE22D COPIES RECEIVED:LTR Q ENCL SIZE:

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

NOTES:Standardized plant. 05000529 RECIPIENT COPIES RECIPIENT COPIES D ID CODE/NAME LTTR ENCL ID CODE/NAME LTTR ENCL PD5 LA 1 1 PD5 PD 1 1 TRAMMELL,C 1 1 THOMPSON,M 1 1 D

INTERNAL: ACNW 2 '

ACRS 2 2 AEOD/DOA 1 1 AEOD/DSP/TPAB 1 1 AEOD/ROAB/DSP 2 2 NRR/DET/ECMB 9H 1. 1 NRR/DET/EMEB 7E 1 1 NRR/DLPQ/LHFB10 1 1 NRR/DLPQ/LPEB10 1 1 'RR/DOEA/OEAB 1 1 NRR/DREP/PRPB11 2 2 NRR/DST/SELB 8D 1 1 NRR/DST/SICBSH3 1 1 NRR DS+/SP,LBSD. 1 1 NRR/DST/SRXB SE 1 1 REG &XIi~~02$ 1 1 1*

RES/DSIR/EIB 1 1 RGN FILE 01 1 EXTERNAL EG&G BRYCE i J ~ H 3 3 L ST LOBBY WARD 1 1 NRC PDR 1 1 NSIC MURPHYgG A ~ 1 1

NSIC POORE,W. 1 1 NUDOCS FULL TXT 1 1 NOTES: 1 1 D

(gg g-y CI /(5 A

D D

NOTE TO ALL "RIDS" RECIPIENTS:

PLEASE HELP US TO REDUCE i'i"ASTE! CONTACT THE DOCUMENT CONTROL DESK, ROO!i1 Pl-37 (EXT. 20079) TO ELliXIINATEYOUR NAME FROM DISTRIBUTION LISTS FOR DOCUliIENTS YOU DON'T NEED!

TOTAL NUMBER OF COPIES REQUIRED: LTTR 35 ENCL 35

I(

Arizona Public Service Company PALO VERDE NUCLEAR GENERATING STATION P.O. BOX 52034 ~ PHOENIX, ARIZONA 85072-2034 e

192-00760-JNL/TRB/RKR JAMES M. LEVINE VICE PRESIDENT December 5, 1991 NUCLEAR PRODUCTION U. S. Nuclear Regulatory Commission Attention: Document Control Desk Mail Station Pl-37 Washington, D.C. 20555

Subject:

Palo Verde Nuclear Generating Station (PVNGS)

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

Special Report 2-SR-91-002 ile'1-020-404 Attached please find Special Report 2-SR-91-002 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 />. 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 Thomas R. Bradish, Compliance Manager, at (602) 393-2521.

Very truly yours, JML/TRB/RKR/nk Attachment cc: '.

J.

F. Conway B. Martin (all with attachment)

D. H. Coe Hg~i~/P

C PALO VERDE NUCLEAR GENERATING STATION UNIT 2 Radiation Monitoring Unit Inoperable Greater Than 72 Hours License No. NPF-51 Docket No. 50-529 Special Report 2-SR-91-002 t a 0 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 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 1604 MST on November 10, 1991. On November 10, 1991, Palo Verde Unit 2 was in a refueling outage with the core offloaded to the spent fuel pool.

ack ro d 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 in the event of 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 effluent and RU-146 being the high range monitor for post-accident radioactive gaseous effluent. 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 also initiates a Fuel Building Essential Ventilation Actuation Signal (FBEVAS) when the activity exceeds a predetermined setpoint. Since RU-145 and RU-146 work in tandem, RU-146 must be declared inoperable if RU-145 is out of service.

On November 7, 1991, at approximately 1604 MST, the B train class 1E 4160 volt bus (2E-PBB-S04) was deenergized to perform scheduled maintenance during the refueling outage. This bus supplies power to Radiation Monitors RU-145 and RU-146. Therefore, RU-145 and RU-146 were removed from service at approximately 1604 MST on November 7, 1991. 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. RU-145 and RU-146 were returned to service at approximately 1334 MST on November 14, 1991 after the B train class 1E 4160 volt bus (2E-PBB-S04) was reenergized.

NRC Document Control Desk Special Report 2-SR-91-002 Page 2 ause o e o erabilit RU-146 was inoperable because its power supply was deenergized for scheduled maintenance during the refueling outage, as described above.

u o eto Radiation monitors RU-145 and RU-146 were returned to an OPERABLE status following reenergization of the B train class 1E 4160 volt bus (2E-PBB-S04) at approximately 1334 MST on November 14, 1991. The monitors were out of service approximately 6 days 21 hours2.430556e-4 days <br />0.00583 hours <br />3.472222e-5 weeks <br />7.9905e-6 months <br /> 30 minutes.

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