ML20056D666

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Summary of Operating Reactors Events Briefing 93-19 on 930526
ML20056D666
Person / Time
Site: Mcguire, Arkansas Nuclear, Farley, McGuire  Southern Nuclear icon.png
Issue date: 06/01/1993
From: Chaffee A
Office of Nuclear Reactor Regulation
To: Grimes B
Office of Nuclear Reactor Regulation
References
IEIN-92-80, OREM-93-019, OREM-93-19, NUDOCS 9308170301
Download: ML20056D666 (22)


Text

e p Cyl June 1,.1993 Q MEMORANDUM FOR: Brian K. Grimes, Director  :

Division of Operating Reactor Support t

FROM: Alfred E. Chaffee, Chief  ;

Eveints Assessment Branch '

Division of Operating Reactor Support

SUBJECT:

OPERATING REACTORS EVENTS BRIEFING MAY 26, 1993 - BRIEFING 93-19 On May 26, 1993, we conducted an Operating Reactors Events Briefing (93-19) to inform senior managers from offices of the l Commission, ACRS, NRR, RES, AEOD, and regional offices of  !

selected events that occurred since our last briefing on May 19, 1993. Enclosure 1 lists the attendees. Enclosure 2 presents the significant elements of the discussed events.

Enclosure 3 contains reactor scram statistics for the week ending May 23, 1993. No significant events were identified for input into the NRC performance indicator program.

- original signed by Edward F. Goodwin for -

Alfred E. Chaffee, Chief  ;

Events Assessment Branch '

Division of Operating Reactor Support ,

Enclosures:

As stated DISTRIBUTION:

1 Central, Files; cc w/ attachments: PDR See next page LKilgore, SECY EAB R/F

- KGray RDennig EGoodwin DSkeen U \

'AB/ DORS .B E EAB/ DORS EAB/ DORS KGray EMurphy EGoodwin AChaffee

[/p/93 ( /l /93 //)/93 [/)/93 OFFICIAL RECORD COPY DOCUMENT NAME: ORTRANS.KAG (G:KAG) '

9308170301 930601

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T Murley, NRR (12G18) E. Murphy (EMCB)_

F. Miraglia, NRR (12G18) J.-Strosnider (EMCB)- i F._Gillespie, NRR (12G18)

  • J.~Partlow, NRR (12G18)

S. Varga, NRR (14E4)

J. Calvo, NRR (14A4) '

G. Lainas, NRR (14H3) i J. Roe, NRR (13E4)

J. Zwolinski, NRR (13H24) i E. Adensam, NRR (13E4)

W. Russell, NRR (12G18)

J. Richardson, 10U1 (7D26) t A. Thadani, NRR (BE2) '

S. Rosenberg, NRR (10E4)

C. Rossi, NRR (9A2)

B. Boger, NRR (10H3)

F. Congel, NRR (10E2)

D. Crutchfield, NRR (11H21)

W. Travers, NRR (11B19) -

D. Coe, ACRS (P-315)  ;

E. Jordan, AEOD (MN-3701)

G. Holahan, AEOD (MN-9112) ,

L. Spessard, AEOD (MN-3701)

K. Brockman, AEOD (MN-3206)

  • S. Rubin, AEOD-(MN-5219)

~

M. Harper, AEOD (MN-9112)

G. Grant EDO (17G21)-

R. Newl ,

GPA (2GS)

E. Beck;ord, RES (NLS-007) '

A. Bates, SECY (16G15)

G. Rammling, OCM (16G15)

T. Martin,-Region I W. Kane, Region I C. Hehl, Region I S. Ebneter, Region II E. Herschoff, Region II S. Vias, Region II  :

J. Martin, Region III E. Greenman, Region III J. Milhoan, Region IV B. Beach, Region IV_

l B. Paulkenberry, Region V K. Perkins, Region V

-bec: Mr. Sam Newton, Manager Events Analysis Department Institute of Nuclear Power Operations I 700 Galleria Parkway.

Atlanta, GA '30339-5957 L. m

L  : O O ENCLOSURE 1 LIST OF ATTENDEES OPERATING REACTORS EVENTS FULL BRIEFING (93-19)

MAY 26, 1993 NAME OFFICE NAME OFFICE A. CHAFFEE NRR G. MARCUS NRR R. DENNIG NRR J. HANNON NRR K. GRAY NRR G. ZECH NRR

[

E. MURPHY NRR G. JOHNSON NRR  ;

E. GOODWIN NRR J. STROSNIDER NRR t B. GRIMES NRR M. VIRGILIO NRR  :

T. ALEXION NRR J. ROE NRR T. KIM NRR W. DEAN NRR.

M. WILLIAMS NRR E. BENNER NRR M. SHUAIBI NRR/RIII J. RICHARDSON NRR D. CARTER NRR D. COE ACRS T. CHAN NRR J. SCARBOROUGH OCM/KR T. TJADER NRR G. BURDICK RES j W. LYON NRR V. BENAROYA AEOD  :

7 TELEPHONE ATTENDANCE' l (AT ROLL CALL) i f

Recions -Resident Inspectors f Region I Palo Verde  !

Region II j Region III Region IV ,

Region V  !

IIT/AIT Team Leaders Misc.

Technical Training Center f

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ENCLOSURE-2.-

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.i OPERATING REACTORS EVENTS BRIEFING 93-19 LOCATION: 10 B11, WHITE FLINT i WEDNESDAY, MAY~26, 1993, 11:00 A.M. ll; l1 i

VARIOUS PLANTS RECENT EXPERIENCE WITH l STEAM. GENERATOR TUBES l

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1 PRESENTED-BY:

EVENTS ASSESSMENT BRANCH l DIVISION 0F OPERATING REACTOR  ;

SUPPORT, NRR-  !

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, .O RECENT EXPERIENCE WITH STEAM GENERATOR TUBES l t

l, OPERATING REACTOR EVENTS BRIEFING-93-19 MAY 26, 1993 EMMETT MURPHY MATERIALS AND: CHEMICAL ENGINEERING BRANCH

-DIVISION OF ENGINEERING, NRR

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.. OUTLINE: :j i

e INTRODUCTION  !

o -SG TUBE DEGRADATION MECHANISMS -

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e GENERAL HISTORICAL TRENDS l 1

.i e .RECENT TRENDS OF CONCERN j ,

e SGTR EVENT AT PALO VERDE 2 j i

o CIRCUMFERENTIAL CRACKS AT ANO-2 1

-o LARGE-VOLTAGE INDICATIONS AT SUMMER-l

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. EXPERIENCE - PWR STEAM GENERATORS i

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ei STEAM GENERATOR' TUBE DEGRADATION PROBLEMS-ARE si 1

WIDESPREAD THROUGHOUT-THE INDUSTRY l

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- 7 SGTR EVENTS :j

- NUMEROUS FORCED OUTAGES .!

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- EXTENSIVE TUBE REPAIRS AND OUTAGE EXTENSIONS l t L,i

- SG REPLACEMENT AT ELEVEN PLANTS TO DATE (ABOUT 1' PLANT- I PER YEAR SINCE 1980) j t

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- SIGNIFICANT RADIATION EXPOSURE-TO-WORKERS i e

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THERE IS NO END IN SIGHT TO THESE PROBLEMS FOR-PLANTS OPERATING WITH THEIR ORIGINAL ~ STEAM' GENERATORS j h

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O O: eartriuG 932, DRAWING 1 of 5-  !

EXAMPLES OF SG TUBE DEGRADATION l MECHANISMS  !

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RECENT TRENDS OF CONCERN e SCC IS DOMINANT DEGRADATION MECHANISM AFFECTING SGS

- 40% THROUGH WALL CRACKS CANNOT BE RELIABLY DETECTED

- CRACKS CAN BE RELIABLY DETECTED BEFORE TUBE INTEGRITY IS IMPAIRED, BUT ONLY IF THE LICENSEE USES THE ,

APPROPRIATE TEST EQUIPMENT (INCLUDING PROBES), TEST

~ PROCEDURES, AND DATA ANALYSIS PROCEDURES AND IF THE '

ANALYSTS HAVE BEEN ADEQUATELY TRAINED AND TESTED ON THESE PROCEDURES

- THERE HAVE BEEN WIDESPREAD DEFICIENCIES IN INSPECTION PROGRAMS THROUGHOUT THE INDUSTRY (SEE INFORMATION NOTICES 92-80, ETC.)

- APPARENT CRACK GROWTH RATES CAN BE HIGH; MID-CYCLE INSPECTIONS ARE SOMETIMES NECESSARY (E.G., MCGUIRE 1 AND 2, ANO-2) e SCC IN FREESPAN IS BECOMING MORE PREVALENT E.G., MCGUIRE 1 AND 2, PALO VERDE 2, FARLEY l

- CAUSED THE TWO MOST RECENT RUPTURES (MCGUIRE 1, PALO VERDE 2)

- EXTRAORDINARY MEASURES TO ENSURE A QUALITY INSPECTION HAVE BEEN NECESSARY TO PROVIDE ASSURANCE OF. TUBE INTEGRITY AT MCGUIRE AND PALO VERDE l

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1r CIRCUMFERENTIAL SCC IS BECOMING MORE PREVALENT '(SEE IN.

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- ~HIGH TUBE INTEGRITY SIGNIFICANCE 'i l

- CAN ONLY BE DETECTED IF LICENSEES USE-RPC PROBES AT -i SUSCEPTIBLE LOCATIONS j i

e -SINCE BEGINNING OF 1992, AT LEAST 4' PLANTS EXPERIENCED. y PERIODS DURING WHICH'1 OR MORE TUBES.HAD INSUFFICIENTE l MARGINS PER RG 1.121 TO SUSTAIN MSLB PRESSURE

- MCGUIRE 1, 2 (1 TUBE EACH) 3

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--ANO-2 (AT LEAST 3 TUBES) l

- PALO VERDE 2 (POSSIBLY 4 TUBES)-

l o EXPERIENCE SHOWS1THAT TUBES WITH FREESPANL AXIAL U

CRACKING OR WITH CIRCUMFERENTIAL CRACKING MAY BECOME ]

VULNERABLE TO RUPTURE WITHOUT SIGNIFICANT: PRECURSOR- j LEAKAGE i q

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a e  ;SGTR EVENT PALO VERDE UNIT 2 j q

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- max LEAK RATE: ABOUT 240 GPM "

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- PRECURSOR LEAKAGE: 5 TO 15 GPD  !

o SGS ARE CE SYSTEM 80, 2 LOOPS, 11000 TUBES PER SG  :

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- HOT LEG TEMPERATURE:- 621 DEGREES F  ;

q e RUPTURE LOCATION: R117C44 IN SG B,.BELOW 09H EGG. CRATE 'l IN FREESPAN l e RUPTURE DESCRIPTION:  !

- AXIAL FISHMOUTH, 2-1/2 INCHES LONG

- EDDY CURRENT INDICATES TOTAL CRACK LENGTH OF 8 INCHES BELOW 09H 1'

e NO EC INDICATION AT PREVIOUS INSPECTION' l.

-e AXIAL FREESPAN INDICATION WAS OBSERVED IN 1991 j

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- MEASURED 1.1 INCHES LONG, 76% DEEP, ABOVE 09H; TUBE PLUGGED  !

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.* 100% BOBBIN-INSPECTION PERFORMED FULL' LENGTH j 1

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- 45 INDICATIONS (38 TUBES) IDENTIFIED WHICH WERE'FOUND' TO AXIAL BY MRPC l e SUPPLEMENTAL INSPECTIONS WITH MRPC  !

- 13 AXIAL INDICATIONS FOUND WHICH WERE-NOT FOUND BY l BOBBIN l

- MRPC SCOPE HAS BEEN EXPANDED  !

o VIDEO CAMERA INSPECTIONS INDICATE VERY HEAVY DEPOSITS j

.ON TUBES e RESINS FOUND ABOVE TUBE BUNDLE t

e EIGHT TUBES PULLED.FROM SG TO EVALUATE:  !

' CRACK MORPHOLOGY l

- CAUSAL MECHANISMS l

- EC EFFECTIVENESS j

  • PLANT STARTUP SCHEDULED : FOR END OF JUNE .

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- NEED FOR CAL UNDER CONSIDERATION ,

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i e1 . ISSUES: ] 4

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- ADEQUACY OF INSPECTIONS ij

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SCOPE  !

-t FAILURE CAUSE; POTENTIAL MITIGATING ACTIONS ,

CRACK GROWTH RATES LEAK RATE LIMITS / MONITORING PROCEDURES -!

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() BRIEFING 93-19 DRAWING 3 of 5 PVNGS SYSTEM DESCRIPTION MANUAL Page 117 of139 -

TITLE REACTOR CODIANT SYSTEM IDENTD1ER RC RCS \ j REvtstON O LEADDISCDUNE Mechanical Figure RC RCS 15 SIG DETAILED DIAGRAM STE AM DRYER _

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MOISTURE -

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FIGURE 11. CE STEAM GENERATOR EGG CRATE b8E SUPPORT PLATE DESIGN j .

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.. . O O CIRCUMFERENTIAL CRACKS AT ANO-2 e SHUT DOWN IN MARCH 1992 DUE TO 0.25 GPM LEAK

- DUE TO CIRCUMFERENTIAL CRACKING AT EXPANSION TRANSITION AT TOP OF TUBESHEET

- THREE TUBES HAD CRACKS EXTENDING 360 DEGREES AROUND TUBE CIRCUMFERENCE WITH AVERAGE DEPTHS BETWEEN 88 AND 94% OF TUBE WALL THICKNESS 1

INADEQUATE MARGINS TO SUSTAIN MSLB

- THESE CIRCUMFERENTIAL CRACKS HAD NOT BEEN DETECTED PREVIOUSLY IN 1991 BECAUSE OF:

USE OF INAPPROPRIATE PROBE (I.E., BOBBIN)

INADEQUATE EC TEST PROCEDURES

- SUBJECT OF IN 92-80 o 100% MRPC INSPECTION PERFORMED IN MARCH 1992 WITH IMPROVED PROCEDURES '

o ANO-2 OPERATED FOR ABOUT 4 MONTHS PRIOR TO THE REFUELING OUTAGE INSPECTION IN SEPT 1992

- 100% MRPC INSPECTION 9

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- --J25'CIRCUMFERENTIAL INDICATIONS

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WORST MEASURED 87% THROUGH WALL'0VER 239 DEGREES'OR-  !

AVERAGE ~OF'58%-0VER 360 DEGREES j; a

WORST TUBE WAS PULLED; 360 DEGREE AVERAGE CRACK-DEPTH WAS 65%

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ALLOWABLE 360' DEGREE CRACK DEPTH IS 79%, CONSISTENT:

WITH RG 1.121 l L 1 L e RESULTS INDICATED POTENT!?.LLY HIGH CRACK GROWTH RATES l j

t AND/OR INABILITY TO DETECT CRACKS-UNTIL THEY ARE DEEP I

e ACCORDINGLY, LICENSEE COMMITTED A MID-CYCLE INSPECTION '

L o- OTHER-ACTIONS AT THAT TIME INCLUDED: ;j

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- I(HOT) REDUCTION; FROM 607 TO 599 DEGREES F.  !

- ADMINISTRATIVE LEAKAGE LIMIT: 0.1 GPM 1

. - N-16-MONITORS .

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-i L - 100%-MRPC EXAMINATION 1

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RESULTS FROM MID-CYCLE INSPECTION IN SPRING 1993: gi

- 48 CIRCUMFERENTIAL' INDICATIONS 1 i I

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-- r - RANGING TO A MAXIMUM OF: b 252 DEGREES AROUND THE CIRCUMFERENCE l

-i 95% MAX THROUGH WALL 360 DEGREE AVERAGE WALL LOSS OF 51% i e PLANT RESTARTED IN MAY 1993 l

  • LICENSEE WILL MEET WITH STAFF IN JUNE 1993.TO JUSTIFY I OPERATION FOR THE BALANCE OF THE CURRENT CYCLE (ABOUT 9 .

MONTHS) PRIOR TO PERFORMING THE NEXT SG INSPECTION n

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.. . O O LARGE VOLTAGE INDICATIONS AT SUMMER e SUMMER HAS WESTINGHOUSE MODEL D3 STEAM GENERATORS e THE SUMMER SGS ARE SCHEDULED FOR REPLACEMENT AT THE END OF THE CURRENT OPERATING CYCLE e ODSCC AT THE TUBE SUPPORT PLATES (TSPS) IS AMONG SUMMER'S DEGRADATION PROBLEMS

- SUMMER HAD REQUESTED A 1 VOLT IPC FOR THE JUST COMPLETED SPRING 1993 REFUELING OUTAGE, BUT WITHDREW THE REQUEST e SEVERAL INDICATIONS RANGING FROM 7 TO 22 VOLTS WERE FOUND DURING THE SPRING 1993 INSPECTION AT THE FLOW DISTRIBUTION BAFFLE PLATES

- THESE RESULTS WERE NELL BEYOND THE ENVELOPE OF DOMESTIC INDUSTRY EXPERIENCE; LARGEST INDICATIONS HAVE NOT EXCEEDED ABOUT 5 VOLTS

. - PREVIOUS INSPECTIONS FOR THESE LOCATIONS INDICATED NO OR VERY LOW LEVEL INDICATIONS SUGGESTS HIGH VOLTAGE GROWTH RATE AND POSSIBLY HIGH CRACK GROWTH RATE

- EXISTING DATA INDICATES THAT BURST PRESSURES CORRESPONDING TO 22 VOLTS-RANGE BETWEEN 2000 AND 6000 PSI 12

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e _ TUBE SPECIMENS WITH9THE LARGE VOLTAGE INDICATIONS'HAVE i BEEN PULLED "00 CHARACTERIZE THE INDICATIONS AND THEIR I TUBE INTEGRITY SIGNIFICANCE. l l

INDICATIONS'AT STANDARD SUPPORT PLATE LOCATIONS WERE WITHIN THE EXPECTED RANGE.(I.E., 5 VOLTS) l i

e PENDING COMPLETION OF PULLED TUBE EVALUATION, LICENSEE CONCLUDES THAT PLANT CAN BE OPERATED'FOR 3.6 MONTHS- .

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.WITH ADEQUATE TUBE INTEGRITY

-I e LICENSEE WILL MEET WITH STAFF IN LATE -JUNE / JULY 1993 TO l DISCUSS THE TUBE PULL RESULTS AND ITS PLANS FOR THE. j BALANCE OF THE OPERATING CYCLE (INCLUDING WHETHER IT

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PLANS A MID-CYCLE INSPECTION) ll

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ENCLOSURE 3 REACTOR SCRAM

-4 Reportins Period: 05/17/93 to 05/23/93-YTD YTD ABOVE SELOW YTD EAll PtANT E UNff pours g CAvsE COMPticAT10ws m 3 g.

05/20/93 DAVIS BESSE 1 100 SA Equipment Falture No -

1 0 1.

05/20/93 SEABR00C 1 100 SM cperating Error No 3 0 3 05/20/93 COMANCHE PEAK 2 72 SA Equipment Falture No 2 0 2 05/21/93 $AINT LUCIE 2 72 SM Equipment Falture No 1 0 1 05/21/93 liATCH 2 65 SM operating Error No 1 0 1 C2ts: Year To Date (YTD) Totals inctu:le Events Within The Calendar fear Indicated By The End Date of The specified Reporting Period

[15-10 Pope:1 05/27/93

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CDMPARISDN OF WEEKLY SCRAM STATISTICS WITH INDUSTRY AVERAGES ,

PER10D ENDING e 05/23/93 NUMBER 1993 1992 1991* 1990* 1989*

OF WEEKLY WEEKLY WEEKLY WEEKLY bEEKLY SCRAM CAUTE SCRANS AVERAGE AVERAGE AVERAGE AVERAGE AVERAGE (YTD) ,

POWER GREATER THAN DR EDUAL TO 15%

EDUlPMENT FAILURE

  • 3 2.2 2.6 2.9 3.4 3.1 CESIGN/1kSTALLATION ERRDR* 0 0.1 - - - --

DPERATING ERRDR* 2 0.4 0.2 0.6 0.5 1.0 MAINTENANCE ERRDR* O 0.5 0.4 - - -

EXTERNAL

  • 0 0.1 - - - -

OTHER* O 0.0 0.2 - -

0.1 Subtetet 5 3.3 3.4 3.5 3.9 4.2 POWER LESS THAN 15%

EDUIPMENT FAILURE

  • O 0.4 0.4 0.3 0.4 0.3 DESIGN / INSTALLATION ERRDR* 0 0.0 - - - -

OPERATING ERRDR* O 0.1 0.1 0.2 0.1 0.3 MAlWTEhANCE ERROR

  • O 0.0 0.1 - - -

EXTERNAL

  • 0 0.0 - - - -

OTHER* 0 0.0 0.1 - - -

Subtotat 0 0.5 0.7 0.5 0.5 0.6 ,

TOTAL 5 3.8 4.1 4.0 4.4 4.8 h

. 1 993 1992 1991 '1990 1989 ND. OF WEEKLY WEEKLY WEEKLY WEEKLY bEEKLY SCRAM TYPE SCRAMS AVERAGE AVERAGE AVERAGE AVERAGE AVERAGE ,

(YTD)

TOTAL AUTOMATIC SCRAMS 2 2.5 3.1 3.3 3.2 3.9 TOTAL MANUAL SCRAMS 3 1.3 1.0 0.7 1.2 0.9 i TOTALS MAY DIFFER BECAUSE OF RDUNDING OFF

  • Detailed breakdown not in database for 1991 and earlier

- EXTERNAL cause included in EQUIPMENT FAILURE k

- MAINTENANCE ERRDR and DESIGN / INSTALLATION ERRDR causes included in DPERAf tkG ERRDR

- CTHER cause included in EDUIPMENT FAILURE 1991 and 1990 3

5 ETS-15 Page: 1 05/27/93

O O FOTES

{

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

0-SCRAMS ARE DEFINED AS REACTOR PROTECTIVE ACTUATIONS WHICH RESULT IN ROD [

MOTION, AND EXCLUDE PLANNED TESTS OR SCRAMS AS PART OF PLANNED SHUTDOWN  !

IN ACCORDANCE.WITH A PLANT PROCEDURE. THERE ARE Ill REACTORS HOLDING AN l OPERATING LICENSE. i

2. PERSONELL 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. L I
4. "OTHER" INCLUDES AUTOMATIC SCRAMS ATTRIBUTED TO ENVIRONMENTAL CAUSES  :

(LIGHTNING), SYSTEM DESIGN, OR UNKNOWN CAUSE. [

i OEAB SCRAM DATA Manual and Automatic Scrams for 1987 ------------------ 435 l Manual and Automatic Scrams for 1988 ------------------ 291 '!

Manua) and Automatic Scrams for 1989 ------------------ 252 i Manual and Automatic Scrams for 1990 ------------------ 226 Manual and Automatic Scrams for 1991 ------------------ 206

-Manual and Automatic Scrams for 1992 ------------------ 212 -

Manual and Automatic Scrams for 1993 --(YTD 05/23/93)-- 78  ;

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