ML20206E359

Summary of Operating Reactors Events Meeting 88-44 on 881108.List of Meeting Attendees,Significant Events & Summary of Reactor Scrams Encl.One Significant Event Identified for Input to Performance Indicator Program

ML20206E359
Person / Time
Site:	Limerick, Vermont Yankee, 05000000
Issue date:	11/10/1988
From:	Lanning W Office of Nuclear Reactor Regulation
To:	Rossi C Office of Nuclear Reactor Regulation
References
OREM-88-044, OREM-88-44, NUDOCS 8811180056
Download: ML20206E359 (19)

Text

-. . . _ . _

a NOVis m MEMORANDUM FOR: Charles E. Rossi. Director Division of Operational Events Assessment FROM: Wayne D. Lanning. Chief Events Assessment Branch Division of Operational Events Assessment

SUBJECT:

THE OPERATING REACTORS EVENTS MEETING November 8, 1988 . MEETING 88 44 On November S. 1988, an Operating Reactors Events meeting (88 44) was held to brief senior managers from NRR. AE00. OSP. RES Commission Staff, and Regional Offices on events which occurred since our last meeting on November 1. 1988.

The list of attendees is included as Enclosure 1.

The events discussed and the significant elements of these events are presented in Enclosure 2. Enclosure 3 presents a sumary of reactor scrams. One significant event was identified for input to NRC's performance indicator program.

I Wayne D. Lanning Chief Events Assessment Branch Division of Operational Events Assessment

Enclosures:

As stated cc w/ Encl.:

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1 MEMORANDUM FOR: Charles E. Rossi. Director Division of Operational Events Assesseent FROM: Wayne D. Lanning. Chief Events Assessment 8 ranch Divition of Operational Events Assessment ,

SUBJECT:

THE OPERATING REACTORS EVENTS MEETING November 8. 1988 - MEETING 88-44 On November 8.1988, an Operating Reactors Eveits :'*eting (88 44) was held to  ;

brief senior managers from NRR. AE00. OSP. REST Commission Staff, and Regional Of fices on events which occurred since our ',st sceting on Neverber 1.1988.

The list of attendees is included as Enclosure 1.

The events discussed and the significant eierents of these events are presented in Enclosure 2. Enclosure 3 presents a summary of reactor scrams. One ,

significant event was identified for input to NRC's performance indicator program.

1 i F

Wayne D. Lanning. Chief ,

> Events Assessment Branch j Division of Operational Events Assessment t

Enclosures:

I As stated l

i cc w/ Encl.: t

See Next Page ,

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_v._-__,_-- _ . _ _ . , _ _ _ _ , _ _ _ _ _ , , _ _ _ _ _ _ , __

o ENCLOSURE 1 LIST OF ATTENDEES OPERATING REACTORS EVENTS BRIEFlWG (88-44)

November 8, 1988 NAME ORGANIZATION NAME ORGANIZATION IT~loger NRR/ADRI f.'E7 Rossi NRR/00EA C. Schulten NRR/00EA M.L Reardon NRR/00EA L. Norrholm OCM/KC W. Minners RES/051R J. Dyer NRR/ORIS 0. La Barge NRR/ORP1-1 W. Butler NRR/P01-2 J. Raleigh NRR/00EA L.B. P.arsh NRR/EMEB L. Zerr NRR/00EA H. Fields OSP A. Vietti-Cook OCM/LZ F. Miraglia hRR/ADR V. Benaroya AE00/0$P l R. Wessman NRR/PD1-3 0. Crutchfield NRR/ADP E. Trottier NRR/P01 3 P. Baranowsky NRR/00EA

ENCLOSURE 2 I

DPERATING REACTORS EVENTS BRIEFING 88-44

[y1NIS ASSESSMENT BRANCH LOCATION;__12-B-11 WHITE FilNT TUESDAY, NOVEMBER 8, 1988, 11:00 A.M.

t VERMONT YANKEE SINGLE LOOP EVOLUTION AND SUBSEQUENT REACTOR POWER OSCILLATION LIMERICK UNIT 1 REMOTE SHUTDOWN PANEL DEFICIENCIES LIMERICK UNIT 1 INSTALLATION del'ICIENCY IN FIRE DAMPER ACCESS DOORS e

', 88-44 yfEdONT YANKEE SINGLE LOOP EVOLUTION AND SUBSEQUENT REACTOR POWER OSCILLATION OCTOBER 29, 1988 PEEEd TRIPPINC 0F RECIRCULATION PljMP AT 55% POWER WITH MINIMUM RECIRCULATION FLOW AND AT A GREATER THAP. 80% R0D LINE RESULTED IN POWER OSCILLATIONS WITH A MAXIMUM OSCILLATION OF ABOUT 20% PEAK TO PEAK.

LAllff FAILURE TO IMPLEMENT GE SIL 380 REV. 1 RECOMMENDATIONS TO PREVENT SINGLE LOOP OPERATION Ik POWER TO FLOW REGIONS OF INSTABILITY IS A MAJOR CONTRIBUTOR. ROOT CAUSE NOT KNOWN AT THIS TIME.

SAFETY SIGNIFICANCE OPERATION AT LOW CORE FLOWS AND HIGH R0D LINE PATTERN RESULTS IN UNSTABLE CONDITIONS IN THE CORE. THESE UNSTABLE THERMAL HYDRAULIC CONDITIONS CAN LEAD TO GREATER THAN DESIGNED POWER PEAKING FACTORS, WHICH MAY LEAD TO VIOLATION OF THE MINIMUM CRITICAL POWER RATIO (MrPR)

SAFETY LIMIT AND POSSIBLE CLADDING DAMAGE.

DISCUSSION o 8:25 A.M. ON OCTOBER 29, 1988, PLANT ENTERED A PLANNED EVOLUTION THAT INCLUDED:

- POWER REDUCTION TO 55% VIA MINIMUM FLOW ON BOTH RECIRCULATION PUMPS (RCP),

- PERFORMANCE OF A MSIV FULL CLOSURE SURVEILLANCE TEST,

- WITHDRAWAL OF 4 SYMMETRIC CRD'S FROM POS 40 TO POS 48 IN PREP FOR SCRAM TIME TESTING.

- 1 RIPPING RECIRC PUMP "A" FOR MG SET BRUSH REPLACEMENT.

c UPON TRIP OF RCP "A" POWER OSClLLATIONS OCCURRED, 2-3 0F WHICH HAD AN ',PPR0X PEAK TO PEAR MI,X OF 20%.

o OPERATOR NOTED APRM SWINGS, (N0 LPRM UPSCALE ALARMS GENERATED),

o IN APPROX. 30 SEC. OPERATING RCP "B" WAS BROUGHT UP TO 70% SPEED, STOPPING OSCILLATION.

CONTACT: J. RALEIGH

REFERENCE:

TELECOMMUNICATION WITH REGION I

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ ___________a

88-44 VERMONT. YANKEE .

O APPR0X 3 HRS LATER, SAME EVOLUTION PERFORMED ON SECOND RECIRC PUMP WITHOUT PROBLEMS o LICENSEE MANAGEMENT WAS NOT INFORMED UNTIL OCT 31, 1988, o PRESENT DATA IS BELIEVED TO SHOW UNIFORM, CORE WIDE OSCILLATIONS.

o CHEMI5TRY EVALUATIONS, OFFGAS MONITORING, AND APRM DATA SUGGEST NO FUEL DAMAGE.

o DID NOT IMPLEMENT Tile Sll 380 REY. 1 REC 0KMENDAT10NS OF ESTABLISHING 80% R0D PATTERN BASED ON PAST CPERATING EXPERIENCE.

o BULLETIN 88-07 MAY BE IN NEED OF ADDITIONAL CLARIFICATION.

0 SIMILAR TO TiiE LA SALLE EVENT IN THAT:

- Sll 380 REV. 1, RICSil 006 SUPP. RECOMMENDATIONS NOT INCORPORATED IN PROCEDURES, o WILL AVOID FUTURE OPS (1 AND 2 LOOP) IN REGION 1 AND MINIM 1ZE OPS IN REGION 11.

O LICENSEE DETERMINED EVENT NOT REPORTABLE VIA 50.72, o EAB INFORMED BY TELECOMMUNICAT10tl WITH REGION. ,

_FDLLOWDE 0 REACTOR SYSTEMS BRANCH WILL REVIEW THE POTENTIAL SAFETY IMPLICATl AND PURSUE ANY GENERIC CONCERNS PENDING THE COMPLETION OF THE l

LICENSEES ANALYSIS.

o EAB WILL PREPARE BULLETIN /.NFORMATION NOTICE SUPPLEMENT AS '*PP 1

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VERMONT YANKEE .

1 1st EVOLUTION:

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88-44 LIMERICK UNIT 1 REMOTE SHUTDOWN PANEL DEFICIENCIES OCTOBER 6, 1988 PROBLEM A FIRE COULD RENDER VARIOUS EQUIPMENT NEEDED FOR A REMOTE SAFE SHUTDOWN t

INOPERABLE.

CAUSE DESIGN DEFICIENCY.

SAFETY SIGNIFICANCE SAFETY COULD HAVE BEEN COMPROMISED SINCE THE ABILITY TO SAFELY SHUTDOWN THE PLANT FROM THE REMOTE SHUTDOWN PANEL (RSP) UNDER THESE CIRCUMSTANCES IS IN QUESTION.

DISCU_S_S_ ION o ONG0ING FIRE PROTECTION REVIEW CONDUCTED ON UNIT 1 AS A RESULT OF 50.55(E) DEFICIENCIES ON UNIT 2.

o FIRE IN THE MAIN CONTROL ROOM, CABLE SPREADING ROOM, OR AUXILIARY EQUIPMENT ROOM COULD CAUSE PRESSURE AND LEVEL INSTRUMENTATION TO BE UNAVAILABLE AT THE RSP.

o INSTRUMENTS POWERED FROM ESSENTI AL ' A.C. THROUGH OWN TRANSFORMER, o WITH THE ASSUMED LOSS OF 0FFSITE POWER, DIESELS ARE SUPPLYING ESSENTIAL A.C.

o FIRE CAUSES DAMAGE TO CABLING POWERING VARIOUS ESW VALVES CAUSING HOT SHORTS AND SPURIOUS ACTUATION OF ESW VALVE.

o COOLING WATER IS LOST TO ALL DIESELS AND THEY EVENTUALLY TRIP ON i

HIGH TEMPERATURE.

o PREVIOUSLY FOUND THAT THE FIRE COULD RESULT IN A LOSS OF SUPPRESSION POOL TEMPERATURE INDICATION AT THE REMOTE SHUTDOWN PANEL.

o HAVE AN ANALYSIS WHICH SAYS THEY WILL EXPERIENCE NO ADVERSE t

CONSEQUENCES FOR UP TO 3 HOURS UNDER THESE CONDITIONS.

o IF FIRE OCCURS PRIOR TO TRANSFERRING CONTROL TO THE RSP, DAMAGE TO THE RCIC FLOW CONTROL INSTRUMENTS MAY OCCUR CAUSING RCIC CONTROL TO BE UNAVAILABLE AT THE RSP. j CONTACT: L. ZERR r

REFERENCE:

50.72 # 13637 AND MORNING REPORT 10/07/88 l

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. LiMERICKUN.IT1 88-44 o NOW OUTSIDE THE BOUNDS OF THE 3 HOUR ANALYSIS BUT THEY FEEL THEIR E0P's WOULD HAVE PROVIDED SUFFICIENT GUIDANCE TO SAFELY SHUTDOWN THE PLANT, ,

1 CORRECilVE ACTION o ROOT CAUSE IS STILL UNDER INVESTIGATION l 0 POSTED FIRE WATCHES IN AREAS AFFECTED.

o FINAL CORRECTIVE ACTION IS UNDER REVIEW BUT WILL INCLUDE A DETERMINATION AS TO WHETHER THIS IS A PROGRAMMATIC BREAXDOWN OR AN ISOLATED CASE.

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_ FOLLOWUP o LER AND ANALYSIS TO BE REVIEWED BY PROJECT MANAGER AND PLANT SYSTEMS BRANCH. PLANT SYSTEMS WILL HAVE THE LEAD.

o SUPPLEMENTAL LER WILL BE REVIEWED WHEN SUBMITTED.

o UNIT 2 50.55(E) WILL BE REVIEWED BY THE REGION AND NRR.

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88-44 LIMERICK UNIT 1 INSTALLATION DEFICIENCY IN FIRE DAMPER ACCESS DOORS OCTOBER 6, 1988 PROBLEM '

BECAUSE OF A DESIGN DEFICIENCY IN FIRE DAMPER ACCESS DOORS THE POTENTIAL i

EXISTS FOR RENDERING VARIOUS ECCS SYSTEMS INOPERABLE, CAUSE I

INSTALLATION DEFECT - CAUSED BY THE FAILURE OF THE SUBCONTRACTOR TO TRANSFER A DESIGN CHANGE FROM A/E DRAWINGS TO THE SUBCONTRACTOR  :

INSTALLATION DRAWING.

1 SIGNIFICANCE o A HIGH ENERGY LINE BREAK (HELB) COULD CAUSE STEAM TO PENETRATE  :

SAFETY-RELATED AREAS WHICH HAVE NOT BEEN ANALYZED FOR A HARSH  ;

ENVIRONMENT.  :

o POTENTIAL FOR DEGRADATION OF SAFETY-RELATED EQUIPMENT IN THESE AREAS. j

o THIS EQUIPMENT INCLUDES MOTOR CONTROL CENTERS FOR RCIC, RHR, AND ADS EQUIPMENT.

0 MOTOR OPERATED VALVES FOR THESE SYSTEMS AND FOR HPCI COULD BE [

l i RENDERED INOPERABLE. l

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o ON OCTOBER 6, LIMERICK, UNIT 1 REPORTED THAT THEY HAD BEEN IN AN l

) UNANALY2ED CONDITION PRIOR TO APRIL 19, 1988.  :

o THREE FIRE DAMPER ACCESS DOORS WERE NOT STRUCTURALLY DESIGNED l -

TO WITHSTAND THE STEAM PRESSURE FROM A HELB.

0 FIRE DAMPER ACCESS DOORS ARE LOCATED ON SEPARATE DUCTWORK EXITING l

THE HPCI AND RCIC PUMP ROOMS AND THE RHR PIPE COMPARTMENT. l 0 IN THE EVENT OF A HELB IN ONE OF THESE AREAS, THE FIRE DAMPER t ACCESS DOORS COULD HAVE FAILED. [

o STEAM WOULD PEkETRATE SAFETY-RELATED AREAS OF THE REACTOR j j ENCLOSURE WHICH HAVE NOT BEEN ANALY2ED FOR SUCH AN EVENT. l l  !

CONTACT: L. ZERR

REFERENCE:

50.72 # 13611 l I

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. LIMERI,CK UNIT 1 88-44 0 EQUIPMEriT WHICH COULD BE AFFECTED INCLUDE:

(1) MOTOR CONTROL CENTERS FOR RCIC, RHR, AND ADS EQUIPMENT.

(2) MOTOR OPERATED VALVES FOR HPCI, IN ADDITION TO MOV's IN THE AB0VE SYSTEMS.

o PROBLEM WAS IDENTIFIED ON APRIL 15, 1988 AS A RESULT OF A UNIT 1/

UNIT 2 COMPARIS0N WALKDOWN (DEFICIENCIES DID NOT EXIST AT UNIT 2),

o DEFICIENCY EXISTED ON UNIT 1 SINCE CONSTRUCTION.

O CLAMPlHG ASSEMBLY WAS INSTALLED BY APRIL 19TH.

o REPORTED ON OCTOBER 3, 1988 WHEN SITE MANAGEMENT WAS MADE AWARE OF THE REPORTABILITY OF THE NONCONFORMANCE.

[DRRECTIVE ACTION IMPLEMENTED SPECIAL MODIFICATION WHICH TEMPORARILY SECURED THE STANDARD

- VENDOR SUPPLIED ACCESS DOORS Wi1H A CLAMPlNG ASSEMBLY UNTil PERMANENT, STRUCTURALLY UPGRADED ACCESS D0 ORS ARE INSTALLED AT THE END OF THE NEXT REFUELING OUTAGE.

FOLLOWUP 0 FORMAL EVENT FOLLOW-UP REPORT TO FOLLOW.

o NO OTHER EAB ACTION.

I'i' N8 *- 1 ENCLOSURE 3 41/07/89 -

- FERF: w n:t th:!tatCRs sishir!C ai tytnis FLA4T ha'I EVthi t'.ENTtti:AlFflC4 GTR $164!F!Cah E tait 10/24/99 at!A CCOLERS Ft20!FID F:R ECCS CFEtal!LITY Ih;.itRAILE 0 FCitMf!AL FOR CR A;TCAL tiltat T! 5 FITIFITRI K IECAL'5E CF $1LT != FED!hs CC:llh5 MATER FL:d Cr sartTV tELAft! IG'.'! " thi

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NOTES

1. PLANT SPECIFIC DATA BASED ON INITIAL REVIEW OF 50.72 REPORTS FOR THE WEEK OF INTEREST. PERIOD 15 M10 NIGHT SUNDAY THROUGH MIONIGHT SUNDAY. SCRAMS ARE DCFINED AS REACTOR PROTECTIVE ACTUATIONS WHICH RESULT IN R00 HOTION. AND EXCLUDE PLANNED TESTS OR SCRAMS AS PART OF PLANNED SHUT 00WN IN ACCORDANCE WITH A PLANT PROCEDURE. THERE ARE 109 REACTORS HOLDING AN OPERATING LICENSE.

P. COMPLICATIONS: RECOVERY COMPLICATED BY EQUIPMENT FAILURES OR PERSONNEL ERRORS UNRELATED TO CAUSE OF SCRAM.

3. PERSONNEL RELATED PROBLEMS INCLUDE HUMAN ERROR, PROCEDURAL DEFICIENCIES. AND kANUAL STEAM GENERATOR LEVEL CONTROL PROBLEMS.

4 "GTHER" INCLUDES AUTOMATIC SCRAMS ATTRIBUTED TO ENVIRONMENTAL CAUSES (LIGHTNING). SYSTEM DESIGN, OR UNKNOWN CAUSE.

o .

MEMORANDUM FOR: Charles E. Rossi. Director Division of Operational Events Assessment FROM: Wayne D. Lanning. Chief Events Assessrent Oranch Division of Operational Events Assessment

SUBJECT:

THE OPERATING REACTORS EVENTS MEETING November 8, 1988 MEETING 88 44 On November S.1988, an Operating Reactors Events meeting (68 44) was held to brief senior managers free NRR. AE00. OSP. RES. Commission Staff, and Regional Offices on events which occurred since our last meeting on Noveeber 1. 1988.

The list of attendees is included as Enclosure 1.

The events discussed and the significant elements of these events are presented in Enclosure 2. Enclosure 3 presents a summary of reactor scrams. One significant event was identified for input to NRC's performance indicator program.

Wayne D. Lanning. Chief Events Assessment Branch 01 vision of Operational Events Assessment

Enclosures:

As stated cc w/ Encl.:

See Next Page 015TRIBUT10N Central File EAB Reading File

. Circulating Copy. EAB Staff MLRearden. EAB 00udirot. EAB LKilgore. SECY POR OFC :EAE/ 0 :C:EAS/00EA :  :  :  :  :

...o.:. . ....:............:............:............:............:............:...........

NAME :ML cardon :W0Lanning  :  :  :  :

...o.:o...........:............:............:............:............:............:...........  :

DATE:11/0(/E0 :11/ /88  :  :  :  :

OrrlCIAL RECORD COPY

It&OTCtSCCAP$UMARY bt[L(Ulhi 11/06/88

1. FLA41 $FECIFIC CATA IAT[ $1T[ Uh!! PC815 $16h&L CAUSE CORPti- Y10 Yip YT)

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. NOTES

1. PLANT SPECIFIC OATA BASED ON IhlTIAL REVIEW OF S0.72 REPORTS FOR THE WEEK OF INTEREST. PERIOD IS M10 NIGHT SUNDAY THROUGH M10 NIGHT SUNDAY. SCRAMS ARE DEFlhED AS REACTOR PROTECTIVE ACTUATIONS WHICH RESULT IN R00 HOTION. AND EXCLUDE PLAhhED TESTS OR SCRAMS AS PART OF PLAhhE0 SHUTOOWN IN ACCORDANCE WITH A PLANT PROCEDURE. THERE ARE 109 REACTORS HOL0thG AN OPERATING LICENSE.

2. COMPLICATIONS: RECOVERY COMPLICATED BY EQUlPMENT FAllVRES OR PERSONNEL ERRORS UNRELATED TO CAUSE OF SCRAM.

3. PER$0hhEL RELATED PROBLEMS INCLUDE HUMAN ERROR, FROCEDURAL DEFICIENCIES, AhD KAh0AL STEAM GEhERATOR LEVEL CONTROL PROBLEMS.

4 'OTHER" INCLUDES AUTOMATIC SCRAMS ATTRIBUTED TO ENVIRONMEhTAL CAUSES (LICHTNING). SYSTEM DESIGN, OR UNKNOWN CAUSE.

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