ML20235Z408

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Summary of Operating Reactors Events Meeting 87-35 on 871013.List of Attendees,Events Discussed,Significant Elements of Events & Summary of Reactor Scrams & Comparison of Wk Statistics W/Industry Averages Encl
ML20235Z408
Person / Time
Site: Indian Point, Harris, Vermont Yankee, San Onofre, 05000000
Issue date: 10/16/1987
From: Lanning W
Office of Nuclear Reactor Regulation
To: Rossi C
Office of Nuclear Reactor Regulation
References
OREM-87-035, OREM-87-35, TAC-66405, NUDOCS 8710210130
Download: ML20235Z408 (17)


Text

,

"w j OCT 161987  ;

i KEMORANDUM FOR: Charles E. Rossi, Director Director of Operational Events Assessment

}

FROM: Wayne Lanning, Chief j Events Assessment Branch i Division of Operational Events Assessment l 1

SUBJECT:

THE OPERATING REACTORS EVENTS fiEETING OCTOBER 13, 1987 - MEETIKG 87-35 On October 13, 1987 an Operating Reactors Events meeting (87_35) was held to brief senior managers from NRR, RES, AE00 and Regional Offices on events which occurred since our last meeting on October 6, 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. The Enclosure 3 provides a summary of reactor scrams and a <

comparison of this week's statistics with industry averages. These were no significant events identified for input to NRC's performance indicator program.

W Wayne Lanning, Chief Events Assessment Branch Division of Operational Events Assessment

Enclosures:

As stated cc w/ Encl.:

See Next Page DISTRIBUTION Central File-  !

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. DCY 16 1937

.! ; '- CC' . ,

T.'Mur'ey . R..Capra J. Sniezek D." Neighbcrs F. Miraglia G..Knighton R. Starostecki ' R . : Cudley ..

E. Jordan. V. Rooney )

'J. Taylor E. Adensam E. Beckford= J.;Suckley W. Russell, RI

J. Nelson Grace, RII- '

B. Davis, RIII, R. D. Martin, RIV J. B. Martin, RV W. Kane,.RI L. Reyes, RII C.'Norelius,'RIII -

J. Callan, RIV D. Kirsch, RV S. Varga. .

D. Crutchfield -4 B. Boger

'G. Lainas G. Holahan i F. Schroeder #

L. Shao J. Partlow B. Crimes F. Congel E. Weiss S. Black T. Martin, F00 E. Merschoff R. Hernan i

H. Bailey L

J. Guttmann C$

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, ENCLOSURE 1 i

, LIST OF ATTENDEES OPERATING REACTORS EVENTS BRIEFING (87-35)

October 13, 1987 NAME. ORGANIZATION NAME - ORGANIZATION, T.' Murley .

NRR J. Partlow NRR/DRIS

- R.W. Starcstecki NRR P. Baranowsky NRR/DOEA F. Miraglia NRR, ADP- W. Lanning. . NRR/00EA C.E. Rossi NRR/DOEA D. Tandi . DEST /SELB W. Jenser .NRR/DOEA G.'Cwalina NRR/DLPQ l D. Oudinot NRR/DOEA B. Boger .NRR/DRP D heighbors NRR/DRP G. Klingler NRR/PPAS y M.L.'Reardon NRR/DOEA- V. Rooney NRR/DRP l P. Lam AE0D/DSP W. Troskoski OED0 l T. Silko AE00 E. Reeves NRR/PD# 2-1 J N. Fields NRR/00EA D. Diehl art!

W. Russell RI D.Crutchfield NRR/DRSP 3

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i E________________ m

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1

, , 1 ENCLOSUREL2 l i

OPERATING EEACTORS EVENTS BRIEFING'87-35. ,

TUESDAY OCTOBER 13,'1987, 11'A.M, THE AGENDA INFORMATION MAY'ALS01BE'0BTAINED BY: DIALING. EXTENSION 27174, i

I' l INDIAN POINT 3' . THIMBLE TUBE' LEAKAGE IN MOVABLE-DETECTOR SYSTEM SAN ONOFRE 1 . VULNERABILITY TOl SINGLE FAILURE VERMONT' YANKEE -CRACKED TERMINATION LUGS ON MOTOR LEADS-L H

HARRIS INADVERTENT (RCS) LEAK:DURING -VALVE-TESTING l

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.- l INDIAN POINT 3- 0 THIMBLE TUBE LEAKAGE IN MOVABLE DETECTOR SiSTEM.

SEPTEMBER-22, 1987 PROBLEM REACTOR COOLANT LEAK IN INCORE DETECTOR THIMBLE.

CAUSE FAILURE TO FOLLOW APPROPRIATE PROCEDURES DURING INITIAL 30 YEAR 3 ISI RESULTED IN DAMAGE TO SEVEN INCORE DETECTOR THIMBLES.

SIGNIFICANCE o POSSIBLE BORIC ACID CORROSION OF COMPONENTS

l 0 POSSIBLE INABILITY TO MEET T/S REQUIRED CALCULATION 0F. PEAKING' 4

FACTORS o COMPROMISE IN REACTOR COOLANT PRESSURE BOUNDARY-INTEGRITY..

DISCUSSION o SEVEN THIMBLE TUBES WERE DAMACED DURING THE LAST REFUELING i OUTAGE WHEN OPERATORS, IN CONDUCTING THE< UNIT'S FIRST 10 YEAR- i ISI, FAILED TO FULLY WITHDRAW THE THIMBLE TUBES AS.PER PROCEDURES o ON 09/22/87 THREE OF DAMAGED TUBES'WERE IDENTIFIED AS LEAKING AND HAD FLOODED OTHER THIMBLE TUBES, FOUR "10" PATH TRANSFER-DEVICES AND TWO "5" PATH TRANSFER DEVICES o TWO 0F THE LEAKS WERE STOPPED COMPLETELY VIA MANUAL ISOLATION VALVES, A THIRD LEAK CONTINUES THRU A UNION UPSTREAM 0F A-.

MANUAL ISOLATION VALVE j 1

CONTACT: N FIELDS -

l H

__ - - - - _ - . O

o LICENSEE FOUND SEVERAL FAILED SELECTOR SWITCHES IN THE "10" PATH DEVICES o THE FLOODED "10" PATH AND "5" PATH SELECTORS WERE CLEANED AND SEVERAL OF THE SWITCHES WERE REPLACED, ALL DAMAGED SW11CHES COULD NOT BE REPLACED BECAUSE PARTS ARE NO LONGER AVAIL ABLE FROM THE MANUFACTJ' REP, o

OTHER TUBES WHICH WERE FLOODED BY THE LEAKINF THIMBLES WERE DRIED USING PRESSURED NITROGEN GAS o

LICENSEE IS UNAWAPE OF THE EXACT NUMBER OF THIMBLE TUDES AVAILABLE BECAUSE SOME HAD BEEN PREVIOUSLY ISOLATED o

T/S REQUIRE 75 PERCENT OF THE UNIT'S 50 TUBES TO BE OPERABLE OR UNIT OUTPUT BE REDUCED TO 90 PERCENT OF LICENSED POWER o

LICENSEE IS REQUIRED TO PERFORM A FLUX MAPPING EXERCISE 10/]4/87, 29 INCORE DETECTORS MUST BE OPERABLE AND APPROPRIATELY D FOLLOWUP o

LICENSEE IS PURSUING OPTIONS WITH RESPECT TO REPLACEMENT o

LICENSEE IS PERFORMING SURVEY OF THIMBLE DISTRIBUTION TO DETERMINE IF FLUX MAPPING CAN BE ACCOMPLISHED. TiIS WILL BE DETERMINED NO SOONER THAN 10/12/87 o RESIDENT INSPECTOR IS FOLLOWING LICENSEE'S ;,CTIVITIES e-o ,

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L-SAN ONOFR.E.1 -l VULNERABILITY.T0 SINGLE FAILURE j OCTOBER 7, 1987 PROBLEM NEWLY DISCOVERED SINGLE FAILURE PDTENTIAL IN SAFETY SYSTEMS 1 CAUSE PREVIOUS. SINGLE FAILURE ANALYSES OF INSUFFICIENT SCOPE'(EVENT SPECIFIC, TIMING, AND COMMON CAUSE FAILUPES NOT CONSIDERED)

SIGNIFICANCE j ENGINEERED SAFETY FEATURES MAY NOT PERFORM THEIR SAFETY FUNCTION i

_DJSCUSSION .,

c ON OCTOBER 7, 1987 LICENSEE REPORTED SINGLE FAILURES OF ELECTRICAL COMPONENTS CAN CAUSE UNANALYZED EQUIPMENT FAILURES o ALL COMPONENT COOLING COULD BE LOST IF THE #2 EUS CCW PUMP IS 3

OUT l

lHE LICENSEE PROPOSES TO LIMIT OPEPATION WHEN THE #2 EUS CCW PUMP IS INOPERABLE o P0TH CHARGING PUMPS COULD BE LOST IF THE #2 BUS PUMP IS SET TO AUTO START FOLLOWING A LOCA' l CHARCING PUMPS PROVIDE POST LOCA RECIRCULATION FLOW THE LICENSEE WILL NOT ALIGN THE #2 BUS CHARGING PUMP TO AUTC START A DEDICATED OPERATOR WILL MANUALLY PROVIDE POWER TO THE #1 CHARGING PUMP'IF REQUIRED (20 MINUTES AVAILADLE).,

CONTACT: D. OUDINOT

4 4

['

i o FOLLOWING LOCA 0R MAIN STEAM LINE BREAK,JFEEDWATER PUMP 1ALSO USED AS SAFETY 1 INJECTION PUMP) MAY:NOT.BE ISOLATED.FFOM THE STEAM GENERATORS FOR UP TO 90 SECONDS THE LICENSEE: PROPOSES T0 CONTINUE OPERATION BY PELYING 0N-OPERATOR ACTION TO MANUALLY ISOLATE THE STEAM GENERATORS

. FOLLOWUP o  !.ICENSEE:

IS-IMPLEMENTING PROCEDURE MODIFICATIONS AS INTERMEDIATE' COMPENSATORY MEASURES WILL DOCUMENT 10/09/87 MEETING WITH NRR REPRESENTATIVES IN REPORT DUE 10/16/87 WILL SUBMIT SINGLE FAILURE ANALYSIS REPORT WITHIN.A MONTH

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- 1 WILL IMPLEMENT COMPONENT AND/0R SPetEM MODIFICATIONS DURING j NEXT REFUELING 0UTAGE IN JULY l u

o NRR AND REGION TO FOLLOWUP l

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_ _ _ . _ _ _ _ _ _ _ _ _ . _ _ _ _ _ . _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ . _ _ _e

.. CPACKED TERMINATION LUGS ON M.O. TOR LEADS VERMONT YANKFF i SEPTEMBER.29, 1987 '

i PROBLEM-CRACKED TERMit'ATION LUGS ON MOTOR LEADS FOR RHR AND CORE SPRAY  !

PUYPS u

CAUSE

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FAILED " AMP" MOTOR LEAD TO POWER LEAD' CONNECTION

. SIGNIFICANCE CRACKING EVIDENCE SUGGESTS VISUAL INSPECTION AND.POUTINE EQUIPMENT-MAINTENANCE TESTS WOULD NOT DETECT FLAWS-IN TERMINATION LUGS-DISCUSSION o SEVERE ARCHING OBSERVED DURING STARTUP OPERABILITY TEST OF RHR PUMP "B" o PUMP FAILURE CAUSED BY AMP-TYPE MOTOR LEAD TO POWER LEAD FAILUPE o LAST FAILURE OF THIS TYPE OCCURRED IN MAY 1987 WHEN THE LICENSEE REPLACED THE TERMINATION ON THE "D" RHR PUMP i

o ADDITIONAL INSPECTIONS FOUND CRACKING EVIDENCE OF VARYit'G l SEVEP,lTY ON SEVEN POWER LEAD TERMINATION LUGS BUT NO

]

CRACKS WEPE FOUND ON MOTOR LEADS 50T WERE FOUND BY VISUAL INSPECTION THE REMAINDEP WEPE FOUND USING 10X MAGNIFICATION-AND/0R DYE. PENETRANT TESTING ONE LUG WOULD NOT HAVE LASTED THE FUEL CYCLif ,

CONTACT: CARL SCHULTEN I

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o PARTIAL CRACKS WERE FOUND'ON HEAVIER DUTY POWER LEAD TERMINATIONS MANUFACTURED BY THOMAS AND BETTS USED ON 'j RHR'S/W AND STATION S/W. PUMPS-o ROOT CAUSE DETERMINATION' IMPLICATES LICENSEE'S INSTALLATION AND MAINTENANCE, TERMINATION LUG MANUFACTilRER A.ND'0THERS LUG PRE-STRESS AND FLAWS APPEARING AT. DIE " STAMPS" 0N THE LUG THROAT 0F THE AMP CONNECTORS SHALLOW " AMP" MANUFACTURER'S DIE STAMPS DEEP!(1/4 THICKNESS) MOTOR NUMBER DIE' STAMP ~(A/E?.GE? MOTOR MANUFACTURER?)

T8B DIE STAMPS LOCATED ON FLAT PORTION OF TERMINATION LUG LICENSEE BELIEVES THAT THE RIGIDITY OF RAYCHEM SPLICES INSTALLED IN 1984 ON TERMINATION BOX CABLES TC9 ETHER WITF TIGHT TERMINATION B0XES MAY LIKELY HAVE. CONTRIBUTED TO LUG FAILURES FOLLOWUP o CONSIDERING AN INFORMATION NOTICE TO HIGHLIGHT THE VERMONT YANKEE EVENT AND DISCUSS THE NEED TO CAUTION MAINTENANCE TECHNICIANS ON THE USE OF ACCEPTABLE DISCONNECT / RECONNECT PROCEDURES FOR TERMINATION LUGS o CONSIDERATION WILL BE GIVEN TO THE NEED T0.SPECIFICALLY ADDRESS AMP AND THOMAS & BETTS CONNECTORS l

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. SHEAPON HARRIS

. INADVERTENT (RCS) LEAK DllRING VALVE TESTIJLG OCTOBER 9, 1987 PROBLEM.

INADVERTENT RCS LEAK TO SUMP AND PRT FROM 2 VENT VALVES FROM THE

)

REACTOR YESSEL VENT SYSTEM  !

CAUSE UNKNOWN - SUSPECT MECHANICAL FAILURE OF THE SOLENGID-0PERATED q (AIR-0 PEN, SPRING CLOSE) GLOBE VALVE SAFETY SIGNIFICANCE' LOSE THE ABILITY T0 ISOLATE THE REACTOR VESSEL OR PRESSURIZER .

TO PRT AND/0R LOSE THE ABILITY TO ISOLATE RCS YENT SYSTEM FROM  !

CONTAINMENT  !

1 DISCUSSION o DURING TESTING OF RCS VENT VALVE RCS-900, VALVES RCS-900 AND 905 OPENED FOR ] MINUTE DURATION UNTIL RCS-900 CLOSED o APPROXIMATELY 120 GALLONS WENT THRU RCS-905 AND 80 GALLON THRU RCS-904 (SUMP) i f

o LICENSEE UNC0VERED A 1980 VENDOR REPORT ADDRESSING SPURIOUS RESPONSE OF VALVES UNDER INCREASING PRESSURE CHANGES )

o A 198] ASPE REPORT CONCLUDED THAT HYDRAULIC-ASSISTED, PILOT- 1 OPERATED VALVES SUBJECTED T0 PRESSURE INCREASES OF 250 PSI /SEC OR GRE"ER WOULD HAVE A. TENDENCY TO MOVE OFF THE VALVE SEAT  ;

i FOLLOWUP i

o OEAB STILL EVAL.UATING CONTACT: J. THOMPSON ,

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REA.:7: s:rp, gan;n Ef1 CLOSURE 3 WED' ECIWS 10/11/!7 i

I. PLANT EFECIFI; CA?A i

LAIl EliE UN:' ( WE: !!r'AL CAJsE cesjty. y; . y7g. yg, CA?!0N! APNE BE!.0a TOTAL 15'4 15%

10/02/97 IEGE: Vs.' .EY  : 52 A UECA - N0 4 4 10 10/(9/51 EE; IC:-  !  ;

47 A . EQU!:/ ELECT. C 2 7' 9 10/:: 27 :: 5 2 9A 0 UN W.% 0 1  !

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II. COMF API SO!'! Or WEEf'Lv F~ATI??IES L ITH I N D'. 'E T ' ' A.'E ri i.E J i SCRAMS F0F WEEl:'ENDIfG i,

10/11/O' E tt ;#; C 4UE.c F'DW ER N'JMDER 1987 1986 1rES q OF WEEF:LY WEEFl.Y WE D 'i. - 1 SC F f,'E ( 5 ) AVER (,GE AVER AGE 4','F: 0.0 F l YTD ( 2. ) ( 4 > lE 'T) 1

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EDUIP. RELATED < 15'/. 1 1.7 1.4 1 .

PERS. RELATED 215' O O.7 0.8- O. 9 CTMER ;15" 1 O . ~. O.2 0 :.

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5 9.1 E.9 1 ': e 2 MANUAL V5 A'JTO SCRAMS TVPE NUMBER 1987 1986 1955 OF WEEMLY- WEEt:LY WEEt :L i j SCRAM 5 AVERAGE AVEF. AGE AVERAGE YTD i

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