ML20210T403

Summary of Operating Reactors Events Meeting 87-02 on 870112 of Events Which Occurred Since 870105.List of Attendees,Events Discussed & Summary of Events Encl

ML20210T403
Person / Time
Site:	Palo Verde, Brunswick, Diablo Canyon, 05000000
Issue date:	01/28/1987
From:	Holahan G Office of Nuclear Reactor Regulation
To:	Harold Denton Office of Nuclear Reactor Regulation
Shared Package
ML20210T369	List: ML20210T364 ML20210T403
References
OREM-87-002, OREM-87-2, NUDOCS 8702180176
Download: ML20210T403 (16)

Text

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% , , , , , #, JAN 2 s 137 MEMORANDUM FOR: Harold R. Denton, Director Office of Nuclear Reactor Regulation FROM: Gary M. Holahan, Director Operating Reactors Assessment Staff-

SUBJECT:

Su MARY OF THE OPERATING REACTORS EVENTS '

MEETING ON' JANUARY 12, 1987 - MEETING 87-02 On January 12, 1987, an Operating Reactor Events meeting (87-02) was held to brief the Office Director, the Division Directors and their representatives on events which occurred since our last meeting on January 5,1987. 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 provides a sunenary of those presented events that will be input to NRC's performance indicator program as significant events and summaries of scrams with complications not fonnally presented in the Operating Reactors Events meeting.

8 9 '

Gary M. Holahan, Director .

Operating Reactors Assessment Staff '

Enclosures:

As stated  ;

cc w/ Encl.:

See Next Page 1

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ENCLOSURE 1 ~

LIST OF~ ATTENDEES OPERATING REACTORS EVENTS BRIEFING (87-02)

JANUARY 12, 1987 NAME DIVISION NAME- DIVISION G. Holahan NRR J. Giitter IE-M. Virgilio NRR E. Trottier- IE D. Tondi NRR K. Kniel DSR0 O. Tarnoff NRR W. Haass IE S. Aggarwal RES K. Eccleston NRR E. Tomlinson NRR D. Crutchfield- NRR R. Emch NRR D. Allison- IE G. Cwalina NRR R. Wright NRR B. Clayton NRR S. Israel AE00 C. Ader OCM J. Milhoan OCM W. Regan NRR D. Muller NRR G. Murphy ORNL D. Vassallo NRR. '

V. Benaroya NRR M. Davis NRR H. Bailey IE G. Lanik IE G. Klingler IE J. Stone IE A. Dromerick IE M. Chiramal AE00 E. Brown AE00 E. Weiss IE R. Baer IE E. Jordan IE J. Rosenthal IE T. Novak NRR C. Rossi NRR D. Humenansky- OCM J. Clifford NRR H. Schierling NRR F. Miraglia NRR F. Schroeder NRR W. Swenson NRR E. Sylvester NRR

ENCLOSURE 2 OPERATING' REACTORS EVENTS BRIEFING 87 JANUARY 12, 1987 BRUNSWICK 2 SCRAM WITH COMPLICATIONS DIABLO CANYON 1 EHC SYSTEM FLUID LEAK - REACTOR / TURBINE TRIP -

VITAL BUS TRIP PALO VERDE 3 DAMAGED ENGINE IN EMERGENCY DIESEL GENERATOR - UPDATE

~

k 1/12/87

~ BRUNSWICK 2 - SCRAM WITH COMPLICATIONS JANUARY 5,-1987 - (E.-SYLVESTER, NRR)

PROBLEM:

LOSS'0F HPCI INJECTION-CAPABILITY - STUCK CLOSED INJECTION VALVE PARTIAL' LOSS OF RCIC INJECTION CAPABILITY _- STUCK OPEN BYPASS VALVE' fBEiEl EQUIPMENT FAILURES

- VALVE MOTOR BURNOUT (HPCI)

- VALVE INTERNAL. MECHANISM FAILURE 1(RCIC) -

SIGNIFICANCE:

P0TENTIAL LOSS OF HIGH PRESSURE REACTOR WATER LEVEL CONTROL DISCUSSION:

TURBINE TRIP AND RESULTANT REACTOR SCRAM DUE TO FAILURE OF GENERATOR AUTOMATIC V0LTAGE REGULATOR DEGRADED VOLTAGE ALSO CAUSED MSIV CLOSURE .

LOW RX WATER LEVEL SIGNAL - RCIC STARTED - HPCI STARTED -

-BOTH IN MIN-FLOW MODE HIGH LEVEL SECURED HPCI AND RCIC HPCI STARTED AND INJECTION VALVE OPENED REMOTE-MANUALLY -

RCIC STARTED HPCI PUT INTO PRESSURE CONTROL MODE RX WATER LEVEL DECREASED - HPCI REINITIATION BUT FAILED TO INJECT - RCIC REINITIATION - SECOND CRD PUMP STARTED RCIC PUT IN RECIRC MODE FOR PRESSURE CONTROL

- CRD FLOW MAINTAINED l

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2 DISCUSSION -CONTINUED OPERATORS ATTEMPTED TO PUT RCIC IN INJECT MODE: SYSTEM FAILED TO OBTAIN FULL INJECTION FLOW CRD FLOW AND PARTIAL RCIC FLOW ADEQUATE RCIC FLOW INCREASED BY PARTIAL CLOSURE OF HPCI RECIRC VALVE PLANT CONDITIONS STABILIZED SUBSEQUENTLY LICENSEE DETERMINED HPCI VALVE MOTOR BURNED-0UT FOLLOWUP EVALUATION OF LIMITORQUE ACTUATOR SHOWED PROPER SETTINGS AND ALIGNMENT RCIC VALVE FAILURE DETERMINED T0 BE MAINTENANCE RELATED '

IMPROPER SET SCREW ALIGNMENT IN ANTI-ROTATION DEVICE FOLLOW-UP:

LICENSEE STILL INVESTIGATING HPCI VALVE MOTOR FAILURE LICENSEE INSPE?, TING ANTI-ROTATION DEVICE INSTALLATION IN ALL SAFETY-RELATED AND SOME NON-SAFETY RELATED VALVES NRR AND REGION FOLLOWING LICENSEE ACTIVITIES L

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2 '

PROBLEM:

• ~

LOOSE. FITTING IN EHC CAUSED LOSS OF EHC FLUID'AND PRESSURE,-

l RESULTING IN EHC PUMP LOCK 0UT, GOVERNOR /STOP VALVE CLOSURE,. i

AND REACTOR AND TURBINE TRIP

PRIOR TO REACTOR / TURBINE TRIP, DURING MANUAL LOAD TRANSFER OF-i VITAL-BUS G (0NE OF THREE) FROM AUX TRANSFORMER T0-STARTUP TRANSFORMER, BUS G TRIPPED ON OVERCURRENT l CAUSE: -

[ LOOSE COMPRESSION FITTING POSSIBLY DUE 'l0 FIRE RESPONSE l ACTIVITIES ON JANUARY 2  !

l BUS G ' RIP INVOLVED POTENTIAL INADEQUATE DESIGN AND/0R l OPERATOR ERROR

SIGNIFICANCE

,

DELAY IN OPERATOR RESPONSE TO INDICATED LOSS OF EHC PRESSURE

! (11/2 HOUR FROM INDICATION TO LOW LEVEL RESERVOIR' ALARM)-

l AUX POWER AND STARTUP POWER BREAKER WERE CLOSED SIMULTANE0USLY FOR '

VERY SHORT TIME DURING MANUAL TRANSFER OF LOAD, LEADING T0 l OVERCURRENT ON BUS DISCUSSION

;

AUX OPERATOR MANUALLY TRANSFERRING POWER SUPPLY FROM AUX l TRANSFORMER TO STARTUP TRANSFORMER  !

OPERATOR INADVERTENTLY LOCKED OUT BUS ON OVERCURRENT SWITCH MUST BE HELD IN POSITION BY OPERATOR DURING TRANSFER (APPR0X. 5 SECONDS) FOR TRANSFER TO GO TO COMPLETION EDG STARTED BUT LOCKED OUT i REACTOR TRIP AND TURBINE TRIP IN ACCORDANCE WITH DESIGN l MANUAL TRANSFER FROM AUX POWER T0'STARTUP POWER l INVOLVES ACTIVATION OF SINGLE SWITCH TO CLOSE AUX POWER j j BREAKER AND TO OPEN STARTUP POWER BREAKER.

• l i OTHER FITTINGS IN EHC FOUND T0 BE TIGHT. LOOSE FITTING POSSIBLY DUE TO BEING KICKED OR VIBRATED. l

! FOLLOWUP:

! LICENSEE TO DETERMINE NEED FOR MORE DETAILED PROCEDURES FOR MANUAL TRANSFER

{ * ,

! RESIDENT / REGION FOLLOWING LICENSEE ACTION j NRR TO EVALUATE MANUAL TRANSFER LIMITATIONS i

__..._._..__.~..,____.___-_._._..._._._._.._.__.-.___._._.J

1/15/87 PALO VERDE UNIT 3 - DAMAGED ENGINE IN EMERGENCY DIESEL GENERATOR - UPDATE DECEMBER 23,'1986 - (E.H. TR0TTIER, IE) .

PROBLEM:

' CONNECTING ROD 9 RIGHT. FAILED AFTER-8 MINUTES OF REQUIRED 2 HOUR, 110% LOAD TEST.

9: RIGHT AND 9 LEFT PISTONS, CONNECTING RODS AND^ COUNTERWEIGHT CAME '

APART. 'SOME PIECES EXITED ENGINE THRU 9 RIGHT INSPECTION DOOR.  ;

CAUSE:-

A HIGH STRENGTH AREA 0F CONNECTING R0D WAS 0VERBORED DURING MANUFACTURE,

'THEN BUILT BACK~UP TO REQUIRED THICKNESS BY IRON ELECTROPLATING. ELECTRO '

PLATED IRON DEVELOPED CRACKS.THAT CAUSED STRESS RISERS-IN BASE METAL. .

SIGNIFICANCE:

THREE:0THER MASTER CONNECTING RODS HAVE BEEN PLATED.!N SAME FAILURE ARE 1 2 RIGHT ALSO IN ENGINE 3B, AND 6 RIGHT IN ENGINE.2A AT PALO VERDE; 3 RIGHT IN ENGINE 1A AT BYRON.

PALO VERDE UNIT 3 NOT YET LICENSED, UNIT 2 EDG DECLARED INOPERABLE AND '

SCHEDULED OUTAGE BEGUN EARLY. BYRON UNIT 1' REPLACING ROD IN LC0 WINDOW.

NINE MORE MASTER CONNECTING RODS HAVE BEEN PLATED IN OTHER NONCRITICAL LOAD AREAS: 1 AT NINE MILE-2, 8 MORE AT BYRON /BRAIDWOOD.

DISCUSSION:

OVERBORED 50-60 MILS ON MAIN AND ARTICULATED' SIDES  !

DEEP OVERBORE MEANT IRON PLATING IN RADIUS-AREA 0F OIL HOLE IRON AND BASE METAL' INTERFACE IN STRESS CONCENTRATION AREA IRON PLATE BRITTLE, NOT FATIGUE. RESISTANT CRACK INITIATED IN RADIUS REGION OF ARTICULATED (UPPER) END OF OIL HOLE, PROPAGATED ACROSS AND DOWN THRU WEB BETWEEN ARTICULATED AND MAIN ROD BEARING METAL EXAM SHOWS FATIGUE ENTIRE LENGTH OF CRACK, NO EVIDENCE OF RAPID BREAK FOLLOW-UP:

RODS FOR PALO VERDE ON ORDER (7 IN MANUFACTURE PROCESS AT COOPER).

CRANK REWORK AND BLOCK REPAIR APPEAR TO BE CRITICAL PATH FOR ENGINE (EST. 10-12 WEEKS BASED ON ZION)~

BYRON ENGINE COMPLETED AT 9:50 PM (CST), FRIDAY, 01/09/87 AND RETURNED TO SERVICE IE/VPB TO CONFIRM ACCEPTABILITY OF IRON PLATING IN NONCRITICAL LOAD AREAS MEETING SCHEDULED FOR LICENSEE (APS), VENDOR (COOPER ENERGY SERVICES)'AND HQ STAFF TO DISCUSS EDG REPAIRS, 01/20/87

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REACTOR SCRAM

SUMMARY

WEEK ENDING 01/11/87.

I. PLANT ~ SPECIFIC. DATA DATE SITE. UNIT. POWER RPS CAUSE COMPLI- YTD YTD- YTDn CATION 3 ABOVE BELOW -TOTAL-15%' 15%

01/05/97 BRUNSWICK' 2 -100 A EQUIP / ELECT, YES 1 0 1-01/06/87 DIABLO CANYON 1 30 A EQUIP /PERS. YES 1 ,0 1 01/06/87 TURKEY POINT. 4 100 A EQUIP / ELECT. NO l' O 1 01/06/87 TROJAN 100 A PERSONNEL NO 1 0 11 01/07/87. LACROSSE 1 97 A EQUIP / MECH NO 1~ 0 11 01/07/87 COOPER. 1 25 A -EDUIPMENT NO

01/0G/87 FARLEY.

1 1 2 1 100 M EQUIP / MECH NO -1 0? 1 01/08/87 WOLF CREEK 1 100 A PERSONNEL / TEST YES .O 01/09/87 FARLEY 1 1 27 A PERSONNEL NO 2 0 2

'01/10/87 PALO VERDE 1 100 A -EDUIPMENT NO- 1 ~' O 1

01/10/87' COOPER 1 22 A PERSONNEL NO 2 01/11/87 BEAVER. VALLEY 1 3 1 100 A- UNKNOWN NO 1 0 01/11/G7 HARRIS 1 0M EQUIPMENT NO O-1 1 1

SUMMARY

OF COMPLICATIONS SITE UNIT COMPLICATIONS i

DRUNSWICK DIABLO CANYON 2 HPCI VALVE FAILED TO OPEN. RCIC ISOLATION VALVE DID NOT FULLY CLOSE WOLF CREEK 1 DURING TRANFER OF LOAD VITAL BUS TRIPFED ON OVERCURRENT 1 PORV INDICATIONS ERRONEOUS B

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II. COMPARISON OF WEEKLY STATISTICS-WITH INDUSTRY' AVERAGES SCRAMS FOR WEEK ENDING

-01/11/87 SCRAM CAUSE POWER NUMBER 1987 1986 OF WEEKLY- WEEKLY ~

SCRAMS (5)' ' AVERAGE AVERAGE

. YTD ,(3)-(4)

• • POWER >15%

EQUIP. RELATED '>15% 7- 5. 0 ~ 4.3 (66%)

PERS. RELATED(6) >15%- 4 .3.1 1. 81 (28%) -

OTHER(7) >15% 1 1.2 0. 4 '_ ( 6%);

• • Subtotal'**

12- 9.3 6.5 ,

• • POWER <15%

EQUIP. RELATED <15% 1 1.2 1. 4 -(58%). -

PERS. RELATED <15% 0 0.6- 0.8-(33%)

0THER <15% 0 0.0 ~O.2 ( 9%)

• • Subtotal **

1 1.8 2.4

• • • Total ***

13 11.1 8.9 MANUAL VS AUTO SCRAMS TYPE NUMBER 1987 1986 OF WEEKLY WEEKLY SCRAMS AVERAGE AVERAGE

• YTD-MANUAL SCRAMS 2 1.2 1.O AUTOMATIC SCRAMS 11 -10.0 7.9' 9

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4 4- NOTES i

- 1. PLANT SPECIFIC DATA BASED ON INITIAL REVIEW OF 50.72 REPORTS

~FOR THE WEEK OF-INTEREST.- PERIOD IS MIDNIGHT SUNDAY THROUGH MIDNIGHT SUNDAY SCRAMS'ARE DEFINED AS REACTOR PROTECTIVE

[

1.

ACTUATIONS WHICH RESULT-IN ROD MOTION, AND EXCLUDE-PLANNED t

TESTS OR SCRAMS AS PART OF' PLANNED SHUTDOWN IN ACCORDANCE j WITH A' PLANT PROCEDURE.

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l 2. REC 0VERY COMPLICATED BY EQUIPMENT FAILURES OR PERSONNEL ERRORS

{ UNRELATED TO CAUSE OF SCRAM.

3. 1986 INFORMATION DERIVED FROM ORAS STUDY!OF' UNPLANNED REACTOR TRIPS IN 1986. WEEKLY DATA DETERMINED BY TAKING TOTAL TRIPS l IN A GIVEN CATEGORY AND DIVIDING BY 52 WEEKS / YEAR.

i

4. IN 1986, THERE WERE AN ESTIMATED TOTAL OF 461 AUTOMATIC AND

MANUAL UNPLANNED REACTOR TRIPS AT 104 REACTORS (HOLDING.

l OPERATINGLICENSES). THIS YIELDS AN AVERAGE RATE OF 4.4 TRIPS j PER REACTOR PER YEAR AND AN AVERAGE RATE OF 8.9 TRIPS PER WEEK

! FOR ALL REACTORS.

5. BASED ON 104 REACTORS HOLDING AN OPERATING LICENSE.

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

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7. "0THER" INCLUDES AUTOMATIC SCRAMS ATTRIBUTED TO ENVIRONMENTAL

{- CAUSES(LIGHTNING),SYSTEMDESIGN,ORUNKNOWNCAUSE.

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, ENCLOSURE 3 Page No. I _

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01/12/B7 SIGHFICANT EVENTS FRE0L'EN:Y FERFORMANCE IN !CATCR No. 3 PLANT NAE EVENT EVE %T !!SCRIPTION CAUSE 0*R DATE

- BRUNSNICK 2 01/05/97 TURBINE TRIP AND RESULTANT REACTOR SCRAM DUE TO FAILURE ECUIPMENTFAILURE 0F SENERATOR AUT0 flat!C VOLTASE RESULATOR-LOSS OF HPCI INJECT!DN CAPAS.DUE TO STUCK CLOSED INJECTION VLVE-PARTIAL LOSS OF RCIC INJECTION EAPAB. DUE TO STUCK DPEN SYPASS VLVE 3!ABLO CANYON ! C1/05/87 REACTOR SCRAM NHEN EHC LEAK RESULTED IN TURl!NE TRIP AND EQUIPRENT FA! LURE I REACTOR TRIP SCRAM COMPLICATED BY LOSS OF VITAL BUS ON MANUAL TRANSFER PRIOR TO REACTOR TRIP N0LFCREEK! 01/06/87 SAFETV INJECTION AND SUBSEQUENT SCRAM N!TH COMPLICATON PERSONNEL EERDR t DUE TO PERSONNEL ERROR. SCRAM COMPLICATED If PORY POSITION-INDICATORFAILURE.ONPOSITIONINDICATORERR0NE00SLV SHONING PORV OPEN OPERATOR CLOSE BLCCK VALVE. .

TROJAN 11/14/86 TURBINE TRIP AND RESULTANT REACTOR SCRAM OUE TO EREONE00$ EQUIPMENT FAILURE H16il V!BRATION $16NAL.0NE !RM FA!LS ON-SCALE.SECOND IRM READSOFFSCALELON.SRMSFAILTOENER611E a

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1/12/87-

-TROJAN - SCRAM WITH COMPLICATIONS NOVEMBER 14, 1986 - (T. CHAN, NRR)

PROBLEM: '

REACTOR TRIP COMPLICATED BY THE LACK.0F RELIABLE NEUTRON FLUX INDICATION CAUSE:

EQUIPMENT MALFUNCTION. ' TURBINE TRIP'DUE TO' ERR 0NE0US HIGH VIBRATION SIGNAL, FOLLOWED BY REACTOR TRIP: IRM (N-35) FAILED

{

ON-SCALE: SRMS FAILED'TO ENERGIZE -

SIGNIFICANCE: ,

LACK 0F POST-TRIP REACTIVITY INFORMATION DISCUSSION:

ABNORMAL WEAR OF TURBINE VIBRATION PROBE TIP CAUSED CHATTERING, RESULTING IN TURBINE TRIP IRM (N-35) FAILED ON-SCALE; IRM (N-36) WAS OVERCOMPENSATED AND READ OFF-SCALE LOWS N-36 DECLARED INOPERABLE' P-6 DID NOT RESET TO AUT0-ENERGIZE SRMS SINCE FAILED IRM (N-35) WAS NOT BELOW SETPOINT MANUAL ATTEMPTS TO RESET P-6 WERE UNSUCCESSFUL SRMS ENERGIZED BY PULLING POWER FUSES FOR IRMS FOLLOWUP:

TRIP SIGNAL FROM VIBRATION PROBE DISABLED PENDING INSPECTION OF BEARING JOURNAL DURING 1987 REFUELING OUTAGE.

REGION V FOLLOWED PLANT ACTIONS d-

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^ 1/12/87 WOLF CREEK - SI/ SCRAM WITH COMPLICATION JANUARY 8, 1987 - (J. GIITTER, IE)

L PROBLEM:

SAFETY INJECTION AND SUBSEQUENT SCRAM WITH COMPLICATION.

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A

. PERSONNEL ERROR / EQUIPMENT-MALFUNCTION- -

j- SIGNIFICANCE:

OPERATORS CONCLUDED THEY HAD A PORV STUCK OPEN BASED ON SINGLE.

POSITION INDICATOR..

DISCUSSION:

i

UNIT AT 100% POWER: STEAM LINE INSTRUMENT CALIBRATION TES.

BEING CONDUCTED.

• ~ r

! NO 1 PRESSURE CHANNEL (534) WAS PLACED IN TEST AT THE SAFEGUARDS

CABINET i

ISC WENT OUT TO LOCALLY ISOLATE NO. 1 CHANNEL PRESSURE TRANSMIT 4

i BUT ISOLATED NO. 2 CHANNEL (535) INSTEAD. THIS PROVIDED 2/3 LOGIC FOR LOW STEAM LINE PRESSURE SI.

}

• 1918 - SI ACTUATION INITIATED. UNUSUAL EVENT DECLARED.

HIGH HEAD CHARGING PUMPS INJECT INTO THE RV. PORVS~ LIFT.

1926 - OPERATOR BELIEVES THAT A PORY IS STILL OPEN BASED ON'THE LIGHT" INDICATION IN THE CONTROL ROOM AND CLOSES THE BLOCK VALVE LICENSEE BEGINS TO NOTIFY AGENCIES OF UNUSUAL EVENT. STATE CAN NOT- '

j BE REACHED. LOCAL SHERIFF MAKES CONTACT WITH STATE. STATE CALLS

• INTO CONTROL ROOM SEVERAL TIMES AND KEEPS SHIFT SUPERVISOR OCC i

2005 - NOTIFICATION IS MADE TO NRC. l I

2112 - OPERATORS REALIZE THAT POWER-IS STILL AVAILABLE TO BLOCK  !

f VALVEI TECHNICAL SPECIFICATIONS REQUIRE THAT POWER SOURCE B i REMOVED WITHIN 1 HOUR. '

2125 - POWER IS REMOVED FROM BLOCK VALVE.  !

LI_CENSEE LATER CONCLUDED THAT PORV WAS NOT STUCK TO OPEN.

VERIFY

! THIS, OPERATORS ARE SENT INTO CONTAINMENT TO MANUALLY CRACK OPEN

! THE BLOCK VALVE, PORV HOLDS.

j FOLLOWUP:

j REGION FOLLOWING LICENSEES INVESTIGATION OF PORV POSITION INDICAT

! FAILURE.

i LICENSEE PLANNED TO REMAIN IN HOT STANDBY TO COMPLETE SOME OTHE

REPAIRS BEFORE RESTARTING.

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! - - - -. . - . - - . - . - - - -