ML17300A761

Special Rept 1-SR-87-016:on 870303,Tech Spec 3.3.3.6 Action 32 Entered Due to Inoperability of Both Channels of Reactor Vessel Water Level Instrumentation.On 870305,time for Restoring Channels to Svc Exceeded.Cause Unknown

ML17300A761
Person / Time
Site:	Palo Verde
Issue date:	03/30/1987
From:	HAYNES J G ARIZONA PUBLIC SERVICE CO. (FORMERLY ARIZONA NUCLEAR
To:	MARTIN J B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V)
References
1-SR-87-016, 1-SR-87-16, 192-00175-JGH-T, 192-175-JGH-T, NUDOCS 8704210307
Download: ML17300A761 (6)

Text

REGULATOR NFORMATION DISTRIBUTION

ŽEM (RIDS)ACCESSION NBR: 8704210307 DOC.DATE,: 87/03/30 NOTAR I ZED: NO DOCKET¹FACIL: STN-50-528 Palo Verde Nuclear Station~Unit i~Ari zona Publi 05000528 AUTH.NAME-.AUTHOR AFFILIATION HAYNES'.G.Arizona Nuclear Pouer Prospect (formerly Arizona Public Serv RECIP.NAME RECIPIENT AFFILIATION MARTIN>J.B.Region 5i Office of Director j

SUBJECT:

Special rept 1-sr-87-016:

on 870303'ech Spec 3.3.3.6 ACTION 32 entered due to inoperability of both channels of reactor vessel water l eve 1 instrumentation.

On 870305>time f or restoring channels to svc exceeded.Cause unknown.DISTRIBUTION CODE: IE01D COPIES RECEIVED: LTR ENCl SIZE: TITLE: General (50 Dkt)-Insp Rept/Notice of Violation Response NOTES: Standardized plant.M.Davis'RR: 1Cg.05000528 RECIPIENT ID CODE/NAME PD5 LA LICITRA, E INTERNAL: ACRS DEDRO NRR ROE'.L NRR/DOEA DIR NRR/DREP/RPB RR ILRB REG IL R 5 FILE 01 EXTERNAL: LPDR NSIC NOTES: COPIES LTTR ENCL 1 0 1 1 2 2 1 1 1 1 1 1 2 2 1 1 1 1 1 RECIPIENT ID CODE/NAME PD5 PD DAVIS'AEOD ENF LIEBERMAN NRR/ADT NRR/DREP/EPB NRR/DR IS DIR OGC/HDS1 RES SPEISi 7 NRC PDR COP IES LT TR Er,'C L 1 1 1 1 1 1 1 1 1 1 1 1'1 1 1 1 1 TOTAL NUMBER OF COPIES REQUIRED: LTTR 25 ENCL 24 I

Arizona Nuclear Power Project P.o.BOX 52034~PHOENIX.ARIZONA 85072-2034 192-00175-JGH/TRB/JHT March 30, 1987 Mr.John B.Martin, Regional Administrator Office of Inspection and Enforcement U.S.Nuclear Regulatory Commission Region V 1450 Maria Lane, Suite 210 Walnut Creek, CA 94596-5368

Subject:

Palo Verde Nuclear Generating Station Unit 1 Docket No.STN 50-528 (License NPF-41)Special Report 1-SR-87-016 File: 87-020-404

Dear Mr.Martin:

Attached please find'a Special Report 1-SR-87-016 prepared and submitted pursuant to Technical Specifications 3.3.3.6 and 6.9.2.This report discusses the inoperability of both channels of the Reactor Vessel Water Level system for a period of greater than 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br />.If you have any questions, please contact Tom Bradish, Compliance Supervisor at (602)932-5300, Ext.6936.Very tru y yours, J.G.Haynes Vice President Nuclear Production JGH/TRB/JHT/cld Attachment cc: 0.M.DeMichele E.E.Van Brunt, Jr.R.P.Zimmerman R.C.Sorenson E.A.Licitra A.C.Gehr INFO Records Center (all w/a)W Pl A~Pl a'3(C3 8704c~10307 870330 PDR ADOCK 05000528 8 PDR

((I h PALO VERDE NUCLEAR GENERATING, STATION UNIT 1 Both Channels of the Reactor Vessel Water Level System Inoperable License No.NPF-41 Docket No.50-528 Special Report 1-SR-87-016 At 0615 on March 3, 1987, Palo Verde Unit 1 was in Mode 3 (HOT STANDBY)when Technical Specification 3.3.3.6 ACTION 32 was entered due to the inoperability of both channels of the Reactor Vessel Water Level Instrumentation.

ACTION 32 requires restoration of the inoperable channels within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> if repairs are feasible without shutting down, or to initiate an alternate method of monitoring the reactor vessel inventory.

Submittal of a Special Report to the commission is also required within 30 days following the event if the channels are not returned to servi,ce within 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br />.At 0615 on March 5, 1987, the time limit for restoring the channels to service was exceeded.This report is being submitted to fulfill the reporting requirement.

Each channel of the Reactor Vessel Level Indication system utilizes eight (8)heated junction thermocouples (HJTC)to generate the signals for 8 indicated levels.In order for each channel to be operable 4 of the 8 sensors must be functional.

Five sensors in each channel are inoperable which renders both channels of the Reactor Vessel Level Indication System inoperable.

Troubleshooting has been conducted, however, the root cause of the sensor malfunction could not be determined.

Further troubleshooting will be conducted during the first refueling outage when the sensors ,can be removed.The channels will be returned to service at the next scheduled refueling outage in accordance with Technical Specification 3.3.3.6 Table 3.3-10 ACTION 32-3.An alternate method of monitoring the reactor vessel inventory is available to the control room operators.

This method utilizes the thermodynamic condition of the Unheated Junction ThermoCouples in the reactor head to determine if a void is present in the reactor'vessel.This method is detailed in approved plant procedures.