ML17304B407

LER 89-009-00:on 890728,inadvertent Train a Fuel Bldg Essential Ventilation Actuation Signal Initiated on Balance of Plant ESF Actuation Sys.Caused by Personnel Error. Individual counseled.W/890822 Ltr

ML17304B407
Person / Time
Site:	Palo Verde
Issue date:	08/22/1989
From:	Haynes J, Shriver T ARIZONA PUBLIC SERVICE CO. (FORMERLY ARIZONA NUCLEAR
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
192-00510-JGH-T, 192-510-JGH-T, LER-89-009-01, LER-89-9-1, NUDOCS 8908300230
Download: ML17304B407 (18)

Text

AC CK1Z RATED Dl FTKBUTION DZMONSTRKT10N SYSTK-y REGULAT . INFORMATION DISTRIBUTIOh,SYSTEM (RIDS)

ACCESSION NBR':8908300230 . DOC'DATE: 89/08/22 NOTARIZED: NO DOCKET 4 FACZL:STN-50-530 Palo Verde Nuclear Station, Unit 3, -Arizona Publi 05000530 AUTH. NAME AUTHOR AFFILIATION SHRIVER,T.D.. Arizona Public Service Co. (formerly Arizona Nuclear Power HAYNES,J.G. Arizona Public Service Co. (formerly Arizona Nuclear Power RECIP.NAME RECIPIENT AFFILIATION

SUBJECT:

LER 89-009-00:on 890728,inadvertent Train A fuel bldg essential ventilation actuation signal:initiated.

W/8 ltr.

DISTRIBUTION CODE: IE22T COPIES RECEIVED:LTR Q ENCL TITLE: 50.73/50.9 Licensee Event Report (LER), Incident Rpt, etc.

~ SIZE:

NOTES:Standardized plant. 05000530 RECIPIENT COPIES RECIPIENT COPIES ZD CODE/NAME LTTR ENCL ID CODE/NAME LTTR ENCL PD5 LA 1 1 PD5 PD 1 1 DAVIS P M. 1 1 INTERNAL: ACRS MZCHELSON 1 1 ACRS MOELLER 2 2 ACRS WYLZE 1 1 AEOD/DOA 1 1 AEOD/DSP/TPAB 1 1 AEOD/ROAB/DSP 2 2 DEDRO 1 1 IRM/DCTS/DAB 1 1 NRR/DEST/CEB 8H 1 1 NRR/DEST/ESB 8D 1 1 NRR/DEST/ICSB 7 1 1 NRR/DEST/MEB 9H 1 1 NRR/DEST/MTB 9H 1 1 NRR/DEST/PSB 8D 1 1 NRR/DEST/RSB 8E 1 1 NRR/DEST/SGB 8D 1 1 NRR/DLPQ/HFB 10 1 1 NRR/DLPQ/PEB 10 1 1 NRR/DOEA/EAB 11 1 1 P RPB 10 2 2 NUDOCS-ABSTRACT 1 1 REG F LE 02 1 1 RES/DSIR/EZB 1 1 R E 01 1 1 R

EXTERNAL: EG&G WILLIAMSPS L ST LOBBY WARD 4

1 4

1 FORD BLDG HOY,A LPDR 1

1 1

1 I

NRC PDR 1 1 NSZC MAYSPG 1 1 NSIC MURPHYPG.A D 1 1 NOTES: 1 1 D

NCTE ZO ALL '%IEG" BECIFHWIS S

PLEASE. HELP US K) REZQCE HASTE! CDNTACr 'IHE DO(ZMENI'OHZROL DESK, RXN Pl-37 (EXT. 20079) XO EEZMQCQR YOUR ?%HE PBCH DIFHG23UTICH LTST8 FOR DO(X2KNIS YOU DEPT NEED!

FULL TEXT CONVERSION REQUIRED TOTAL NUMBER OF COPIES REQUIRED:'LTTR 41 ENCL 41

0 ~~

Arizona Public Service Company P.O, BOX 53999 PHOENIX, ARIZONA 85072-3999 192-00510-JGH/TDS/DAO August 22, 1989 U. S. Nuclear Regulatory Commission NRC Document Control Desk Washington, D;C. 20555

Subject:

Palo Verde Nuclear Generating Station (PVNGS)

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

Licensee Event Report 89-009-00 File: 89-020-404 Attached please find Licensee Event Report (LER) No. 89-009-00 prepared and submitted pursuant to IOCFR 50.73. In accordance with IOCFR 50.73(d), we are herewith forwarding a copy of the LER to the Regional Administrator of the Region V office.

If you have any questions, please contact T. D. Shriver, Compliance Hanager at (602) 393-2521.

Very trul yours, J. G. Haynes Vice President Nuclear Production JGH/TDS/DAJ/kj Attachment cc: W. F.. Conway (all w/a)

D. B. Karner E. E. Van Brunt, Jr.

J. B. Hartin T. J. Polich H. J. Davis A. C. Gehr INPO Records Center 8908300~30 @908~@

ADQCK 05000530 S PNU

If NRC Form 344 0 UA. NUCLEAR REOULATORY COEMCISSION (SO)3)

APPROVED DMS NO. 3)%04)04 UCENSEE EVENT REPORT LER) EXPIRES: SISIISS FACILITY NAME (II DOCKET NUMBER (1) PA TITLE (CI Palo Verde Unit 3 0 s o o 0 530ioF07 Inadvertent Fuel Building Essential Ventilation ESF Actuation EVENT DATE (5) LER NUMBER (SI REPORT DATE (7I OTHER FACILITIES INVOLVED ISI MONTH DAY YEAR YEAR 4 E 0 O'E NT I A L REVS~ MONTH DAY YEAR FACILITYNAMES DOCKET NUMBER(S)

NUM4ER y.r3 NUMBER N/A i) 0 5 0 0 0 0 728 8 9 8 9 009 000 82 28 9 N/A 0 5 0 0 0 OPE RATINO THIS REPORT IS SUBMITTED PURSUANT TO THE REOUIREMENTS OF 10 CFR )I (Cool onr or moto ol thr Iollornnp) (III MODE ( ~ I 6 20A02(41 20A05(cl 50.73(o) (2) (h) 73.71(41 POWER 20A05( ~ l(1)(il 50.34(cl(ll 50.73(o)(2)hl 73.71(cl LEVEL p p p 20.405(o l)1) iii) 50,34 (c) (2) 50.73 (I I l2) (r W I 'OTHER (Sorrily In Aptttrtt priory onp In Tort, IYIIC Form 20A05( ~ llll(nil 50.73( ~ I(2) (il 50.73( ~ ) (2) (rii (Al SSSAI 20A05(x )(ll(h) 50.73(ol(1) (iil 50.73(o)(2l(riSIIS)

IPPWs. gr'L4@o.: 20A05( ~ )(1)(rl 50.73(o) (2)(iiil 50.73 (4) (2) (xl LICENSEE CONTACT FOR THIS LER (11)

NAME TELEPHONE NUMBER AREA CODE Timothy D. Shriver, Compliance Manager 6 02 39 3- 25 21 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT (13)

CAUSE SYSTEM COMPONENT MANUFAC REPORTABLE MANUFAC. EPORTABLE TURER TO NPRDS COMPONENT ympm, TVRER X V I BK R G1 84 SUPPLEMENTAL REPORT EXPECTED (ICI MONTH DAY YEAR EXPECTED SU 5 M I SS ION YES Ill yH, complot ~ EXPECTED StlpotISSIOII DATEI DATE (15) 1 1 3 0 8 9 ABBTRAc'7 I(,imit to tctx) IprcrL I r., rpproximrtrly Attrrn tinplr corer typrwrittrn lmrd (14)

At approximately 0430 MST .on July 28, 1989, Palo Verde Unit 3 was in Mode 6 (REFUELING) with the Reactor Coolant System. at ambient temperature and core reloading in progress when an inadvertent Train HAH Fuel Building Essential Ventilation Actuation Signal (FBEVAS) was initiated on the Balance of Plant Engineered Safety Feature Actuation System. The Train '"A" FBEVAS resulted in the designed cross-trips of Train "BR FBEVAS and Train "AR and RB" Control Room Essential Filtration Actuation Signals (CREFAS). The actuati.on occurred when a Maintenance individual reset the Spent, Fuel Pool Area Radiation. Monitor (RU-31) Remote Indicating and Control Unit without ensuring that the channel was placed in "bypass." Following the actuation, Control Room Essential Ventilation System Train "BH fan tripped. All other components operated as designed. Radiation Protection personnel verified .that no actual high radiation levels existed in the area of the Spent Fuel Pool Area Monitor.

The root cause of this event was a cognitive personnel error by an APS Maintenance individual who did not ensure that RU-31 was placed in bypass in accordance with approved procedures. As corrective action, the individual has been counseled.

Previous similar events were reported in LER's 528/85-033 and 528/87-026.

NRC farm 344

NRC Felte SSSA I90>l US. NUCLEAR REGULATORY COMMISSION LICENSEE EVENT REPORT'(LER)'TEXT CONTlNUATlON APPROYEO OMS NO 3150-0104 EXPIRE5: 4/31/IEI FACILITY NAME III COCKET NUMSER Ql LER NUMSER IS) PAGE ISI SSQI/SNT/AL REVISION NUMFSA NUMSSR Palo Verde Unit 3 0 s 53 08 0 0 00 02 ttxt /// ee>>e eeeee N NNeeed. ceo ee/eeeee/ ///IC Feee ~ 9/ I 'It) 0 0 0 9 9 QF 0 7 DESCRIPTION OF WHAT OCCURRED:

A. Initial Conditions:

At approximately 0430 HST on July 28, 1989, Palo Verde Unit 3 was in Mode 6 (REFUELING) with the Reactor Coolant System (RCS)(AB) at ambient temperature. Core (AC) reloading was in progress.

B. Reportable Event Description (Including Dates and Approximate Times of Hajor Occurrences):

Event Classification: Engineered Safety Feature Actuation.

At approximately 0430 HST on July 28, 1989, an inadvertent Train "A" Fuel Building Essential Ventilation Actuation Signal (FBEVAS)(VG)(JE) was initiated on the Balance of Plant Engineered Safety Feature Actuation System (BOP ESFAS)(JE). The Train "AU FBEVAS resulted- in the designed cross-trips of Train UBU FBEVAS and Train UA" and "B" Control Room Essential Filtration Actuation Signals (CREFAS)(VI)(JE). The actuations occurred when a maintenance individual (utility, non-licensed) reset the Spent Fuel Pool Area Radiation Honitor (RU-31)(ND)(IL)(RI) Remote Indicating and Control Unit (CPU) without ensuring that the channel was placed in "bypass." Following the actuation, Control Room Essential Ventilation System (VI) Train "B" fan (FAN) tripped. All other

-components operated as designed. Radiation Protection personnel (utility, non-licensed) verified that no actual high radiation levels existed in the area of the Spent Fuel Pool Area Honitor (RU-31).

RU-31 monitors for a release of activity due to a fuel handling accident in the Fuel Building (ND). This monitor provides a HIGH-HIGH dose rate alarm (RA) initiation signal via its Remote Indicating and Control Unit to BOP ESFAS which performs the safety function of isolating the normal ventilation system (VG) and activating the essential ventilation system. To prevent inadvertent ESF actuations during testing, troubleshooting, or calibration activities, it is necessary that the radiation monitor be removed from the on-line mode and placed in the bypass mode ai the BOP ESFAS panel (PNL). The bypass mode allows the operation of the various monitor interlocks (IEL) and trips for functional

.testing, but does not allow the monitor to actively interface with BOP ESFAS. Therefore, trip signals generated as a normal consequence of testing and calibration activities do not result in unnecessary ESF actuations.

Prior to the event, at approximately 0425 HST on July 28, 1989, the Unit 3 Spent Fuel Pool Area Radiation Honitor (RU-31) went off-line (i.e., would not communicate with its Remote Indicating and Control

'lee I /IAM esse 19 4)s

NRC PSIIII 444A I94A US. NUCLEAR REOULATORY COMMIEE1ON LlCENSEE EVENT REPORT (LER) TEXT'CONTlNUATION APPROVEO OME NO 9150~144 EXPIRES: 4/3111EI PACILITY NAME 111 OOCKET NUMEER Ql LER NVMEER 141 ~ ACE LTI YEAR gj?, SEOVENTIAL VVII~ %% ' I AEVISIQN gL HVMOSA Palo Verde Unit TEXT Nt IIIoIS SOoCe It ~. IIm ~ 3 HRC FOnn 3$ 5l LU 1171 o 5 o o o-53 08 Unit). RU-31 was declared inoperable and Fuel Building Essential 9 0 0 9 0 0 0 3 OF 0' Ventilation was initiated pursuant to Technical Specification 3.3.3. 1 ACTION requirements. Radiation Protection personnel (utility, non-licensed) were unsuccessful in attempts to reset the monitor; therefore, they contacted Instrumentation & Control (I&C)

Haintenance personnel (utility, non-licensed) for assistance. A maintenance individual went to the Remote Indicating and Control (RIC) Unit for RU-31 and noted that the RIC was not functioning properly (i.e., locked-up). The individual was aware of an investigation of a ground isolation elsewhere in the plant and believed that this had resulted in power supply (JX) perturbations which would cause RU-31 to Ulock-up" and go off-line.

In order to reset the RIC, it is necessary to momentarily de-energize the Unit by either pressing the reset button or pulling the power supply fuse (FU). However, since a loss of power to the RIC and/or RU-31 will cause a Train "ALv FBEVAS, it is necessary to place Train RAU FBEVAS in bypass prior to de-energizing the RIC to prevent an inadvertent ESF actuation.

At approximately 0430 HST, the individual de-energized the RIC without first contacting Control Room personnel (utility, licensed) and having Train RA" FBEVAS placed in bypass per approved procedures. This resulted in a Train RA" FBEVAS and designed cross trips of Train UBU FBEVAS and Train "A" and UB" CREFAS's. The BOP ESF actuation signals resulted in actuations of the Fuel Building Essential Ventilation System (VG) Trains UAR and "B", the Control Room Essential Ventilation System (VI) Trains UAR and "B", the Essential Chilled Water System (KH) Trains RAU and UB", the Essential Cooling Water System (BI) Trains RAR and UB" and the Essential Spray Pond System (BS) Trains UAU and "BR. Following the actuations, the Train "BR Control Room Essential Ventilation System fan tripped. All other components operated as designed.

The BOP ESF actuations were identified by Control Room personnel (utility, licensed) as a result of main control board (HCBD) annunciations (ANN). There were no operator actions which contributed to the cause of this event. No other ESF actuations occurred and none were necessary. Operations personnel verffied.

that the ESF actuations did not occur as a result of high radiation levels in the Fuel Building.

C. Status of structures, systems, or components that were inoperable at the start of the event that contributed to the event:

Prior to the event, the Spent Fuel Pool Area Radiation Honitor (RU-31) was inoperable as discussed in,Section I.B. No other structures, systems, or components were inoperable at the start of the event which contributed to the event.

~ AC ~ I?A V 944 4 IS 4SI

NRC Po<co SSSA 198) I US. NUCLEAII AECULATOAYCOMMISSIONJ LICENSEE EVENT REPORT (I ER)'TEXT CONTINUATION APPROVED OMS NO SISOMIOC EXPIRES: S/31/SS PACILITY NAME Ill OOCXET NUMSEA QI LER NUMSEII 191 ~ ACE 131 gg SEOUENT/*L AEVcoOcc NVMOOR NVMOPO Palo Verde Unit 3 o s o ohio 53 0 8 9 0 0 9 00 04 oF 0 TEXT ///cocoo cpoco N cooooocL'op ecoooooo/A/RC Focco ~'c/ Illl D. Cause of each component or system failure, if known:

The cause of Control Room Essential Ventilation System Train "B",

fan tripping was an intermittent failure in the fan's power supply breaker (BKR). The cause of the power supply breaker malfunction is under investigation in accordance with the APS root cause evaluation program. The investigation to determine the root cause is expected to be completed by October 31, 1989. The results of the investigation will be reported in a supplement to this LER expected to be submitted by November 30, 1989.

The cause of the Spent Fuel Pool. Area Radiation Monitor (RU-31) communication problem discussed in Section I.B could not be determined. Troubleshooting was conducted in accordance with an approved work authorization document and no problems were discovered. After resetting the monitor, the monitor operated properly and was returned to service't approximately 2151 HST on July 28, 1989.

E. Failure mode, mechanism, and effect of each failed component, if known:

The cause of the intermittent failure in the Control Room Essential Ventilation System Train "B" fan power supply breaker is under investigation as described in Section I.D. The intermittent failure resulted in a loss of power to the Control Room Essential Air Handling Unit fan which resulted in Train "B" Control Room Ventilation not functioning (i.e., no air flow). This did not result in a loss of Control Room Ventilation since the 'A" Train started and operated properly. Each train is designed to provide 100 percent capacity.

The Spent Fuel Pool Area Radiation Monitor (RU-31) problem discussed in Sections I.B and I.D resulted in the inability to remotely access RU-31 indicated radiation levels and the inability of the monitor to initiate a FBEVAS if a HIGH-HIGH alarm condition occurred.

F. For failures of components with multiple functions, list of systems or secondary functions that were also affected:

Not applicable - no component failures occurred which had multiple functions.

G. For failures that rendered a train of a safety system inoperable, estimated time elapsed from the discovery of the failure until the train was returned to service:

Control Room Essential Ventilation System Train UB" was inoperable 4AC /4AM I~ Oo 19 Slc

J HRC Perm 444A US. HUCLEAR AECULATORY COMMIEQOH 19S) I Il LlCENSEE'EVENT REPORT (LER) TEXT CONTINUATlON AI'PROYED OMS HO 4140MISa EXPIRES: SINAI ISS PACILITY HAME Ill DOCKET HUMSEA IEI L'ER HUMSER 141 ~ ACE ISI 4 4 0 V 4 H T I A I. a191 nn4 v n4 no H

~ rvnnaaa nrvMaaa TEXT N'are Pal o Verde Uni aaace H eaareverE nnaa ~t 3 IYIIC fcvm Jul Sl II7) from approximately 0430 0 s HST on 0 0 0 July 28; 5 3 0 1989 until 0 0 it was 9 0 0 returned 05oFO 7.:

to service at approximately 0041 HST.,on August 12, 1989. Train RBR was inoperable approximately 14 days 20 hours2.314815e-4 days <br />0.00556 hours <br />3.306878e-5 weeks <br />7.61e-6 months <br />. During this period of inoperability, RA" Train Control Room Essential Ventilation remained operable.

No other failures occurred which rendered a train of a safety system inoperable; however, the Spent Fuel Pool Area Radiation 0425 HST on July Honitor (RU-31) was inoperable from approximately 28, 1989 until it was returned to service at approximately 2151 HST RU-31 was inoperable approximately 17 hours 26 on July 28, 1989.

minutes.

H. Hethod of discovery of each component or system failure or procedural error:

The intermittent failure in the Control Room Ventilation System Train RBR fan power supply breaker was discovered during troubleshooting conducted after the event. The Spent Fuel Pool discovered Area Radiation Honitor (RU-31) communication problem was annunciation in the Control by Control Room personnel via local Protection Room and subsequent investigation by Radiation personnel. There were no procedural errors discovered.

I. Cause of Event:

The cause of the event was a cognitive personnel error on the part of the APS individual (utility, non-licensed) responsible for resetting the Spent Fuel Pool Area Radiation Honitor (RU-31) Remote Indicating and Control Unit (RIC) without first notifying Control Room personnel and ensuring that the monitor was placed in bypass.

The error was contrary to approved procedural controls and cautionary labeling affixed to the RIC. There were no procedural There were errors or deficiencies that contributed to the event. that directly no unusual characteristics of the work location contributed to the event.

The cause of the equipment malfunctions are described in Section I.D.

J. Safety System Response:

The following automatic safety system responses occurred:

Fuel Building Essential Ventilation Control Room Essential Ventilation Essential Chilled Mater System .-

nna 4 IOann 19 44 ~

NRC fere>> 544A e

19451 US. NUCLEAR RECULATORY COMM1551ON LICENSEE EVENT REPORT ILER) TEXT CONTINUATION APPROYEO OMS RO 5150~145 EXPlRES: Eall&

f ACILI'TYNAME Ill OOCXET NUMEER 12)

LER NUMEER L91 PACK 151 rrLA>> 5KOUKIITIAL "' KVI5ION NUMeee Pre IIUIIeee Palo Verde Unit 3 ohio o o 5 30 89 0 0 9 0 0 '06 oe 0 7; TEXT Ef rrerre eeeee 4 Ieewed. eee ereerrejfeRC hnII JILL'el Ill)

Essential Cooling Mater System "Essential Spray 'Pond System K. Failed Component Information:

The failed breaker is manufactured by Brown Boveri Co. It is a 480 volt Model K-600S.

II. ASSESSMENT OF THE SAFETY CONSE(UENCES AND IMPLICATIONS OF THIS EVENT:

There were no safety consequences or implications resulting from the ESF actuation. The Spent Fuel Pool Area Honitor (RU-31) monitors for a release of activity due to a fuel handling accident in the Fuel.

Building. RU-31 performs the safety function of initiating an isolation of the normal ventilation system and activating the essential ventilation system on a HIGH-HIGH dose rate alarm. As discussed in Section I.B., Fuel Building Essential Ventilation was started by Control Room personnel when RU-31 became inoperable. RU-31 continued to monitor radiation levels at the time of the event initiation and no abnormal radiation levels were detected. Additionally, Radiation Protection personnel verified that no abnormal radiation levels existed. There was no fuel handling accident which initiated this event.

There were no safety consequences resulting from the malfunctioning Train- "B" Control Room Essential Ventilation fan/breaker as Train "A" started properly and provided 100 percent capacity Control Room Essential Ventilation.

I I I. CORRECTIVE ACTIONS:

A. Immediate:

As immediate corrective action, Radiation Protection personnel (utility, non-licensed) verified that no abnormal radiation levels existed and Control Room personnel (utility, licensed) verified that the FBEVAS was not the result .of a fuel handling accident.

B. Action. to Prevent Recurrence:

As corrective action to prevent recurrence, the involved individual was counseled. An 'investigation of this event is being conducted in accordance with the PVNGS Incident Investigation Program and is expected to be completed by August 30, 1989. The results of this investigation will be reported in the supplement to this LER if it would significantly change the reader's perception of the course, significance, implications, or consequences of the event; or if it results in substantial changes to the corrective actions described above.

reC ~ OeM 5eee 19 45I

NRC PAIM 555A U4 NUCLEAR REGULATORY COMMIT/(ON 1S4)1~

LICENSEE EYENT REPORT (LER) TEXT CONTINUATION APPROVEO OME NO 5150&105 EXPIRES: b/lUN PAC1L1TV NAME 111 OOCKET NUMEER Ql LE11 NUMbER PAGE 151 011 SEAR SEQUENTIAL ASVISION

%Y ~ IuMSSA ~ III&4\A Palo Verde Unit s 53 089 0 09 00 07 oF 0 7 TEXT illmCW ance M ~. II>> rdaeenal 3

AIl1C FOIIII ~ bl Ill) o a a o IV., PREVIOUS SIMILAR EVENTS:

'Previous similar events were reported in Unit 1 LER's 328/85-033 and 528/87-026. As discussed in Section I.I, the cause of the event reported in this LER (530/89-009) was a cognitive personnel error.

Cognitive personnel errors are primarily the result of mental lapses and are not normally correctable with revised procedures or additional training. Therefore, the corrective actions for thenoted previous events would not have prevented this event. It should be that corrective actions for previous events were successful in preventing recurrence of the event for approximately two years and that this is the first event of this type which has occurred in Unit 3.

~ IAC 511IIM 555A IS 55I

.~

C