ML20129G314

Summary of Operating Reactors Event Briefing 96-12 on 961016.List of Attendees,Significant Elements of Discussed Events & Reactor Scram Statistics for Wks Ending 960922,29 & 1006 & 13 Encl

ML20129G314
Person / Time
Site:	Oconee
Issue date:	10/23/1996
From:	Chaffee A NRC (Affiliation Not Assigned)
To:	Martin T NRC (Affiliation Not Assigned)
References
OREM-96-12, NUDOCS 9610300061
Download: ML20129G314 (18)

Text

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October 23, 1996 MEMORANDUM T0: Thomas T. Martin. Director Division of Reactor Program Management FROM: Alfred E. Chaffee. Chief [0riginal signed by)

Events Assessment and l Generic Communications Branch Division of Reactor Program Management

SUBJECT:

OPERATING REACTORS EVENTS BRIEFING OCTOBER 16. 1996 - BRIEFING 96-12 On October 16. 1996, we conduct i an Operating Reactors Events Briefing  !

(96-12) to inform senior managei; from offices of the Commission. OE. AE00.

NRR and regional offices of selected events that occurred since our last briefing on September 18. 1996. Attachment I lists the attendees.

Attachment 2 presents the significant elements of the discussed events.

Attachment 3 contains reactor scram statistics for the weeks ending September 22. September 29. October 6. and October 13. 1996. Two significant events were identified for input into the NRC Performance Indicator Program (Attachment 4).

Attachments: As stated (4) l cc w/atts:

See rext page CONTACT: Kathy Gray. NRR (301) 415-1166 4

DISTRIBUTION: (w/atts) qCentral Files. El PUBLIC

/

9 PEB P SED Dpg f; DOCUMENT NAME: G:\KAG\0RTRANS To reconve e copy of tNo document, Indicate in the boa: "C" = Copy without attachment / enclosure *E' = Copy with attachment / enclosure "N" = No copy 0FFICE PECB(6 w 1E PECB ,E PECB g N C/PECB 4, g~ g _7 Ric i //J47 NAME KGray:]kd ' TKoshy& EGoodwinb AChaffedpf# L /cenx i DATE 10/19/96 010/2/196 10/RJ /96 10/g3 /96 0FFICIAL RECORD COPY 4) 9610300061 961023 ORO NRRB Cf(y 'I3[

PDR PDR ,

bh ,

. - - _ _ -. - .--_- - . - . ..-..= - _ - . _ - - . _ . . . - . .

)

4 CC: I F. Miraglia NRR (0-12G18) D. LaBarge. NRR (0-14H25) i F. Gillespie NRR (0-12G18) H. Berkow. NRR (0-14H25)

R. Zimmerman NRR (0-12G18)

A. Thadani. NRR (0-12G18)

B. Sheron. NRR (0-12G18) i S. Varga. NRR (0-14E4) t l J. Zwolinski. NRR (0-14H3)  ;

J. Roe. NRR (0-13E4) s E. Adensam. NRR (0-13E4)

G. Lainas. NRR (0-7026) l' G. Holahan. NRR (0-8E2)

M. Virgilio. NRR (0-8E2) l

D. O'Neal. NRR (0-10E4)  !

}' B. Boger. NRR (0-9E4)

M. Markley ACRS (T-2E26) l E. Jordan. AE0D (T-4D18)

C. Rossi. AE0D (T-4A9)

F. Congel. AE0D (T-4D28)

R. Barrett. AE0D (T-4A43) l l S. Rubin AEOD (T-4028) i

M. Harper. AE0D (T-4A9) '

W. Leschek. AE0D (T-4A9) l V. McCree. ED0 (0-17G21) ,

J. Gilliland PA (0-2G4) '

D. Morrison. RES (T-10F12)

W. Hill. SECY (0-16G15) i H. Miller Region I l R. Cooper. Region I S. Ebneter. Region II E. Herschoff Region II S. Vias. Region II A. Beach Region III ,

J. Caldwell. Acting. Region III J L. Callan. Region IV J. Dyer. Region IV K. Perkins. Region IV/WCF0 G. Fader. INP0 ,

J. Zimmer. DOE l j

. . . -. . _ ~ . . - - - . . - . . - . . - .- . - - - _ . .- .

i' s

LIST OF ATTENDEES OPERATING REACTORS EVENTS FULL BRIEFING (96-12)

OCTOBER 16. 1996  !

s M 0FFICE .NRiE OFFICE S T. Koshy NRR D. Desaulniers NRR A. Chaffee NRR K. Jabbour NRR K. Gray NRR J. Kauffman OE i E. Goodwin NRR J. Sharkey OCM/McGaffigan J. Carter NRR J. Beall OE/McGaffigan T. Martin NRR E. Rossi AE00 G. Hornseth NRR G. Hammer NRR r

R. Wessman NRR '

TELEPHONE ATTENDANCE (AT ROLL CALL) ,

t Recions Resident Insoectors Region I Region II >

Region III Region IV j;

)

!!LL.

T. Peebles, AIT Team Leader ATTACHMENT 1 I

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j OPERATING REACTORS EVENTS BRIEFING 96-12 l LOCATION: 0-10B11, WHITE FLINT l WEDNESDAY, OCTOBER 16, 1996 11:00 A.M.

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OCONEE, UNIT 2 STEAM LINE RUPTURE AND PERSONNEL INJURIES (AIT)

PRESENTED BY:

EVENTS ASSESSMENT AND GENERIC COMMUNICATIONS BRANCH DIVISION OF REACTOR PROGRAM MANAGEMENT, NRR ATTACHMENT 2

i l' 96-12

OCONEE, UNIT 2 STEAM LINE RUPTURE AND PERSONNEL INJURIES I l SEPTEMBER 24, 1996 PROBLEM i M0ISTURE SEPARATOR REHEATER DRAIN PIPE RUPTURE DURING l POWER ASCENSION. STEAM FROM THE RUPTURE CAUSED l SIGNIFICANT INJURY TO SEVEN MEMBERS OF PLANT STAFF.

! CAUSE WATER HAMMER INDUCED PRESSURE TRANSIENT RESULTED IN A

} DUCTILE RUPTURE THAT HAPPENED TO INITIATE AT A PRE-EXISTING BASE METAL FLAW. GE0 METRY OF THE PIPING NEAR THE

, FLAW CAUSED AN AMPLIFICATION OF THE STRESS.

i j SAFETY SIGNIFICANCE PERSONNEL HAZARD l PLANT TRANSIENT

\

l DISCUSSION

! e ON SEPTEMBER 24, 1996 NON-LICENSED OPERATORS AND INSTRUMENT TECHNICIANS WERE REALIGNING M0ISTURE

SEPARATOR REHEATER DRAINS. (OPERATION PERFORMED AT APPR0X. 50% POWER LEVEL)

! e THE REALIGNING WAS TO DIVERT M0ISTURE SEPARATOR DRAIN i TANK WATER FLOW FROM THE MAIN CONDENSER TO THE j FEEDWATER HEATERS BY MANUALLY OPENING HD-94 AND HD-91.

i i CONTACT: T. K0 SHY, NRR/DRPM/PECB AIT: YES

! T. PEEBLES, AIT TEAM LEADER

REFERENCE:

10 CFR 50.72 #31053; SIGEVENT: XES

{! PN29665 l

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!' OCONEE, UNIT 2 96-12 e THE 18-INCH HEADER RUPTURED AT A JUNCTION WITH AN i ABANDONED 45-DEGREE CAPPED STUB. THE HEADER JOINS TWO

! LOOPS OF 12-INCH HEATER DRAIN PIPING.

! e THE RUPTURE OPENED THE STUB TO ITS FULL LENGTH INCLUDING 45 DEGREE OPENING ON THE WELDED CAP. ON THE 18 INCH PIPE IT OPENED ABOUT EIGHT INCHES THROUGH THE l SADDLE PLATE.

i e THE LICENSEE BELIEVES THAT THE LINE THAT CONNECTED THE

! SECOND STAGE REHEATER DRAIN TANKS TO THE FEED WATER l HEATERS HAD WATER AT ROOM TEMPERATURE, AND WATER STEAM j MIXTURES AT LOOP SEALS.

I e WHEN MANUAL VALVES 2HD-94 AND 95 WERE OPENED, FLOW TO l THE CONDENSER THROUGH DIVERT VALVES (2HD 25 AND 26) l ACCELERATED WATER IN LOOP SEALS. WHEN STEAM i SUBSEQUENTLY PASSED THROUGH THE RELATIVELY COLD PIPES i THE STEAM RAPIDLY COLLAPSED, WHICH FURTHER ACCELERATED i THE WATER SLUG BEHIND IT. THE COLLISION 0F THE WATER l SLUG WITH THE UPSTREAM WATER IS HYP0THESIZED TO HAVE j CAUSED A WATER HAMMER.

i e THE RUPTURE COULD HAVE OCCURRED WHEN THE

" WATER-HAMMER-CAUSED" IMPACT FORCE TRAVELED DOWN THE FLUID AND WAS CONCENTRATED BY THE REDUCER AND 45 DEGREE l DEAD LEG.

1 i e H0T WATER AT APPR0XIMATELY 406F / 250psig FLASHED TO

! STEAM, SEVERELY BURNING PERSONNEL IN THE AREA.

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! OCONEE, UNIT 2 96-12

} AIT FINDINGS i e PLANT HAD LONG HISTORY OF WATER HAMMER PROBLEMS.

SUBSTANTIAL CHANGES RECOMMENDED IN NOVEMBER 1995 AND BEFORE BUT NOT IMPLEMENTED WERE AS FOLLOWS:

l INSTALLATION OF CHECK VALVES TO PREVENT BACKFLOW

BETWEEN SECOND STAGE REHEATER DRAINS l IMPROVEMENTS TO M0ISTURE SEPARATOR REHEATER LEVEL i CONTROLS l -

REHEATER STEAM CONTROL VALVE DESIGN CHANGES i

! e A GENERAL PROCEDURE THAT WAS USED ONCE BEFORE WITHOUT A l WATER HAMMER WAS SCHEDULED TO BE CHANGED.

! e WITH SIGNIFICANT ENGINEERING INVOLVEMENT, VALVE l REALIGNMENT WAS SUCCESSFULLY DONE IN JULY. THE MANUAL

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i VALVES WERE CRACKED OPEN AND LEFT FOR 35 MINUTES BEFORE l OPENING THEM FURTHER.

i l e TEMPERATURE DIFFERENCE BETWEEN DRAIN TANKS AND PRESSURES AT VARIOUS LOCATIONS IN THE DRAIN SYSTEM

! WERE MONITORED CLOSELY TO ASSURE THE FLOW WOULD BE l IN THE FORWARD DIRECTION.

! e PRIOR TO THIS EVENT, OPERATORS WERE NOT BRIEFED ON l LESSONS LEARNED FROM THE SUCCESSFUL JULY EVOLUTION

) OTHER THAN TO OPEN THE VALVES SLOWLY. THIS RESULTED IN l AN INITIAL OPENING 0F 1/4 0F THE WAY.

i e THE LICENSEE'S SUBSEQUENT METALLURGICAL EXAMINATIONS

! WERE WELL ORGANIZED. OTHER THROUGH-WALL CRACKS FOUND j ON THE PIPING FROM OTHER LOOP HEATER DRAIN LINES AT l CONNECTION TO THE HEADER.

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OCONEE, UNIT 2 96-12 j e VISUAL AND NON-DESTRUCTIVE EXAMINATIONS AT UNITS 2 & 3 REVEALED MISSING WELD SADDLE PLATES (WHICH HAVE NOT YET  !

BEEN CONFIRMED TO BE REQUIRED BY THE ASME B31.1 CODE),

l AND INDICATIONS IN UNIT 1 0F PIPING AND HANGER l DISCREPANCIES.  !

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! e THE AB0VE FINDINGS PROMPTED THE LICENSEE TO SHUT DOWN l UNITS 1 & 3.

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' e METALLURGICAL EXAMINATION OF THE BREAK RESULTED IN I PRELIMINARY CONCLUSION THAT THE RUPTURE WAS DUE TO 100%

DUCTILE FRACTURE DUE TO OVERPRESSURE, THE MAGNITUDE OF WHICH WOULD HAVE RUPTURED A NEW PIECE OF PIPE. 1 NRC ACTIONS e THE SPECIAL INSPECTION THAT STARTED ON SEPTEMBER 25, 1996 WAS CHANGED TO AN AIT ON SEPTEMBER 28, 1996, BASED ON MANAGEMENT REVIEW 0F THE EVENT.

e NRR & AE0D PROVIDED SPECIALISTS FOR ON-SITE SUPPORT OF THE INSPECTION.

e AN INFORMATION NOTICE IS BEING CONSIDERED TO INCREASE FACILITY AWARENESS OF THE POTENTIAL SERIOUSNESS OF WATER HAMMER EVENTS.

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. REACTOR SCRAM Reporting Period: 10/07/96 to 10/13/96 YTD YTD ,

A80VE BELOW YTD PAI[ PWT 4 WIT 2BER ILP[ $8W$[ COMPLICATIONS j3 jj} g

,/09/96 MINE YAMEE 1 90 SA Maintenance Error No 2 0 2 10/11/96 SEQUDYAN 2 47 SM Equipment Falture NO 1 2 3 Not0: Year To Date (YTD) Totals Include Events Within The Calender Year Indicated By The End Date of The Specified Reporting Period ETS 10 Pe9e:1 10/16/96

. l COMPARISON OF WEEKLY SCRMI STAT!$ TICS WITH INDUSTRY AVERAGES PERI @ ENDING 10/13/96 NUMBER 1996 1995 1994 1993 1992 0F WEKLY WEKLY WEEKLY WEKLY WEEKLY SCRAM CAUSE SCRAMS AVERAGE AVERAGE AVERAGE AVERAGE AVERAGE (YTD)

POWR GREATER TMAN OR E3uAL 70 15%

EOUIPMENT FAILURE 1.51 1.83 1.52 1.83 1

2.62 DESIGN /lNSTALLATION ERROR 0 0.12 0.12 0.08 0.04 -

OPERATING ERROR 0 0.07 0.15 0.21 0.27 0.31 MINTENANCE ERROR 1 0.56 0.38 0.54 0.52 0.50 EXTrRNAL 0 0.17 0.21 0.17 0.13 -

OTHER 0 0.10 0.06 -

0.02 -

$4 total 2 2.53 2.75 2.52 2.81 3.43 POWER LESS TMAN 15%

EQUIPMENT FAILURE O 0.22 0.10 0.27 0.38 0.42 DESIGN / INSTALLATION ERROR 0 0.00 -

0.02 - -

OPERAflWG ERROR 0 0.10 0.13 0.08 0.13 0.15 MAINTENANCE ERROR 0 0.07 0.08 -

0.02 0.08 EXTERNAL 0 0.0J - -

0.04 -

OTHER 0 0.00 - - - -

$4 total 0 0.39 0.31 0.37 0.57 0.65 i

TOTAL 2 2.92 3.06 2.89 3.38 4.08 9

1996 1995 1994 1993 1992 No. OF WEEKLY WEEKLY WEEKLY WEEKLY WEEKLY SCRAM TYPE SCRAMS AVERAGE AVERAGE AVERAGE AVERAGE AVERAGE 4

(YTD)

TOTAL AUTOMATIC SCRAMS 1 1.80 1.92 2.19 2.44 3.06 TOTAL MANUAL SCRAMS 1 1.12 1.13 0.69 0.94 1.02 TOTALS MAY DIFFER BECAUSE OF ROUNDING OFF ETS 14 Page: 1 10/16/96

REACTOR scaAsi Repertins Perled: 09/30/96 ta 10/M/M YTD YTD A80VE BELOW YTD

MK PLAa

T a insif 25BE IIt1 fa K tzarticAficas ja ja Igig 10/06/M PEACN BOTToll 2 88 SA maintenance Error 1

10 0 1 0 1 4

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i Noto Yeer To Date (YTD) Totals include Events Within The Calender Year Indicated By The End Date of The Specified toporting Period ET5 10 Pese:1 10/08 M 1

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, CG PARISON OF W EKLY SCRAM STAT!sTICS WITN I S USTRY AVERAGES PER! 3 E W ING 10/06/96 4

NUMBER 1996 1995 1994 1993 1992 0F WEKLY W EKLY WEKLY WEELY WEKLY SGAN CAUSE SCRAMS AVERAGE AVERAGE AVERAGE AVERAGE AVERAGE (YTO)

POWR GREATER TNAN OR EQUAL TO 15%

i feUIPeENT FAILURE O 1.53 1.83 1.52 1.83 2.62 DESIGN / INSTALLATION ERROR 0 0.13 0.12 0.08 0.04 -

3 OPERATING ERROR D 0.08 0.15 0.21 0.27 0.31 mINTENANCE ERROR 1 0.55 0.38 0.54 0.52 0.50 EXTERNAL 0 0.18 0.21 0.17 0.13 -

OTNER 0 0.10 0.06 -

0.02 -

54 total 1 2.57 2.75 2.52 2.81 3.43 POW R LEss TNAN 15%

EGUIPMENT FAILURE O 0.23 0.10 0.27 0.38 0.42 DESIGN / INSTALLATION ERROR 0 0.00 -

0.02 - -

OPERATING ERROR 0 0.10 0.13 0.08 0.13 0.15 mlNTENANCE ERROR 0 0.08 0.08 -

0.02 0.08 EXTERNAL 0 0.00 - -

0.04 -

OTNER 0 0.00 - - - -

5 4 total 0 0.41 0.31 0.37 0.57 0.65 TOTAL 1 2.98 3.06 2.89 3.38 4.08 1996 1995 1994 1993 1992 NO. OF WEEKLY WEEKLY WEEKLY WEEKLY WEKLY SCRAM TY'f SCRAMS AVERAGE AVERAGE AVERAGE AVERAGE AVERAGE (YTO)

TOTAL AUTOMATIC SCRAMS 1 1.83 1.92 2.19 2.44 3.06 10TAL M NUAL SCRANs 0 1.13 1.13 0.69 0.94 1.02 TOTALS MAY OIFFER BECAUSE OF ROUNDING OFF EVS 14 Page 1 10/08/ %

,.. - == aem m m e w ** e-% ee. ..w s,.,y=u *.w g e e. ape m. .., e m . -=. _

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REACTOR sta411 g.

seporting Perled: 09/Z3/96 to 09/29/96 i

YTD YTD l

ABOW BELOW YTD E MT & WIT g Iggg gg gggyLICAf ttals jg 3 g 09/N/96 OCIulEE 2 60 set DeeIyt or Inetalieti 11 0 1 0 1 4

0 1

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aloto: Year To Date (YTD) Totals Include Events Within The Calender Toer Indicated By The End Date of The specified toporting Period ET5 10 Pope:1 10/03/ %

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• i ClumARIION OF WEKLY StaAN STATISTICS WITN ISUSTRT AVERAGES

] PER!W E W INS 09/29/96 2

NumaER 1996 1995 1996 1993 1992 0F WEKLY WEKLY WEKLY WEKLY WEKLY ERAN CALM SCRANS AVERAGE AVERAEE AVERAGE AWERAGE AVERAGE (YTD)

POWR WEATER TNAN OR EeuAL 70151

EalipeENT FAIList 0 1.56 1.83

' 1.52 1.83 2.62 DESleN/ INSTALLATION ERAGR 1 0.13 0.12 0.08 0.04 -

l OPEaATINS Easot 0 0.08 0.15 0.21 0.27 0.31 i MINTENANCE Enact 0 0.54 0.38 0.54 0.52 0.50 EXTEANAL 0 0.18 0.21 0.17 0.13 -

i OTNER 0 0.10 0.06 - 0.02 -

l S4totet 1 2.59 2.75 2.52 2.81 3.43 PO WR LESS TNAN 151 EQUIMENT FAILLRE O 0.23 0.10 0.27 0.38 0.42 4

DEBl W / INSTALLATION ERROR 0 0.00 -

0.02 - -

OPERATINS kESOR 0 0.10 0.13 0.08 0.13 0.15 NAINTENANCE ERAGR 0 0.08 0.08 -

0.02 0.08 EXTERNAL 0 0.00 - -

0.04 -

i OTNER 0 0.00 - - - -

1 Setotet 0 0.41 0.31 0.37 0.57 0.65 J

TOTAL 1 3.00 3.06 2.89 3.38 4.08 I

d l 1996 1995 1994 1993 1992

No. OF WEKLY WEKLY WEKLY WEKLY WEKLY l SCRAM TYPE SCRAMS AVERAGE AVERAGE AVERAGE AVERAGE AVERAGE (YTD)

J l TOTAL AUTIMATIC SCRAMS 0 1.85 1.92 2.19 2.44 3.06 TOTAL MANUAL SCRAMS 1 1.15 1.13 0.69 0.94 1.02 t

! TOTALS MAY DIFFER BECAUSE OF ROUS ING OFF 4

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,3 MACTS SCRAfl Reporting Perled: 09/16/96 to 09/22/96 l 4

j YTD YTD ABOWE DELtW YTD E PLAET & INIf M 112[ fe g CE N LICATItais jil jH E1 I

09/16/96 FITZPATRIK 1 100 SA Insintenance Error YES 1 1 2 l I

j 09/16/96 BIG to m Po!NT 1 55 SA E gipment Failure NO 1 0 1 ;

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, 09/14/96 CtBIANCNE PEAK 2 100 84 other N0 2 0 2 l l 09/22/96 000K 1 38 SA Other No 2 0 2 4

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Note Year To Date (YTD) Totals Include Events Within The Calender Year Indicated By The End Date of The specified Reporting Period ETS 10 Pose:1 09/23/96

._m.. .,_,- - m_ . . _ _ _ ..

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. MemIPfl0N OF CayLICATICB(S) 09/16/96 TO 09/22/ M i

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1111 31,1 IIBrtICATIMS FIT 2 PATRICK 1 LP Am Fhr TURBINES' RUPTURE DISCS AUPTURED, ALLOWIN STEAN INTO TUtSINE BUILDI N. UNUIUAL EVENT DECLARED.

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b' NOTES i

1. PLANT SPECIFIC DATA BASED ON INITIAL REVIEW OF 50.72 REPORTS FOR THE WEEK OF INTEREST. PERIOD IS MIDNIGHT SUNDAY THROUGH MIDN;tGHT SUNDAY.

SCRAMS ARE DEFINED AS REACTOR PROTECTIVE ACTUATIONS WHICH RESULT IN ROD MOTION, AND EXCLUDE PLANNED TESTS OR SCRAMS AS PART OF PLANNED SHUTDOWN 4

IN ACCORDANCE WITH A PLANT PROCEDURE. THERE ARE 111 REACTORS HOLDING AN OPERATING LICENSE.

! 2. PERSONNEL RELATED PROBLEMS INCLUDE HUMAN ERROR, PROCEDURAL DEFICIENCIES, AND MANUAL STEAM GENERATOR LEVEL CONTROL PROBLEMS.

3.

COMPLICATIONS: RECOVERY COMPLICATED BY EQUIPMENT FAILURES OR PERSONNEL

ERRORS UNRELATED TO CAUSE OF SCRAM.

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

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j OEAB SCRAM DATA i

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M2nual and Automatic Scrams for 1987 ------------------ 435 i M2nual and Automatic Scrams for 1988 ------------------ 291 i Minual and Automatic Scrams for 1989 ------------------ 252

! Manual and Automatic Scrams for 1990 ------------------ 226 M nual and Automatic Scrams for 1991 ------------------ 206

M

nual and Automatic Scrams for 1992 ------------------ 212 M2nual and Automatic Scrams for 1993 ------------------ 175 1

Manual and Automatic Scrams for 1994 ------------------ 150 Manual and Automatic Scrams for 1995 ------------------ 159 i

Manuel and Automatic Scrams for 1996 --(YTD 10/13/96)-- 120 l

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OPERATING REACTC3t PUNTS SIGNIFICANT EVECTS SORT > Event Date OUERY> Event Type SIG & Close out Date >= 05/29/96 & Event T p " "SIE" DATE OF 50.72 OR Cloescui PLANT & ImIT MLE,1 M DESOtIPTION OF EVENT SIGNIFICANCE BRIEFING PRESENTER M ARKANSAS NUCLEAR 1 05/19/9630495 A recctor trip occurred efter motfunctions of main Other - Reector trip with 96-06 BENEDICT R. NIGMLIGNT foodwater pop controls. The "B" OTSG bolted dry complications caused by stuck open efter one of its sein steen safety velves stuck mein steen safety velve.

open.

i NADDAM NECK 1 09/01/96309Y2 Inedvertent introchsetion of nitrogen into the RCS Safety-Related Cootirle System W 11 SENNER E. NIGNLIGNT

& ring shutdoun. Omtstionable transfer of RCS inventory and levet fluct ations.

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