ML20024B605

Current Events Power Reactors,Cracks Discovered in Collet Housings of Control Rod Drives, Aug-Sept 1975

ML20024B605
Person / Time
Site:	Crane
Issue date:	09/30/1975
From:	NRC COMMISSION (OCM)
To:
References
TASK-03, TASK-06, TASK-3, TASK-6, TASK-GB B&W-0162, B&W-162, NUDOCS 8307110015
Download: ML20024B605 (10)

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'f.'I::TS SILICTI3 FRO:". FI?OITS SU3F.ITTED *"O F2 WITED STATES EUCLE.Ut i

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. CT.C.S DISC 07I?2D 1:; C9"2'T EDUSII; :S OF CO DI. P.OD DRIVES

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-j Ddi:n a refueli=g cutage. at E=it 3 of the Dresden Kuclear Power S:5: ion j

e5d.vhils overhauling a ccairol rod driva, a cr'ack was discovered i:2 the 2.'

,i' coll'c: hensi=g shgre tube. T6:r other c::: ol rod drives were at. ".labla i

for scruti=y; i=spectics revealed 'esch of their collet housii,s to be

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j cracked-In ea:h case, the cracks occurred in the collet housing short?

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tube belev the vater p~ orts in the area of increased vall thichness.

1 Subse.usst inspection of eighteen control rod drive =achanis=s revaaled 3

that elef.m reds displayed se=e indicatie:s of cracking is the cells-l W

hcusing area.

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(*,. J Ceheral. Ele:::ic.co pany's Euclear Energ7 Division vas advised of this.

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possible ger.eric proble=.. Exx:ina:1c. cf. their tes: ' ontrol rod d='_ve

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c ctchanis=s revealed cracks of.the colle housings nearl ide::ical to the.

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feur co:::si rod driv'es ext '=ed.at Dresfan-3.

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General Ele:::ic had been'av.are of. si=ilar crackin'; on test colle: tousings J-

' ef c'entrol' rods that had tiaes scra=-cy:iti 2000 ti=es, and mora severe.

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crr.ching c= : echanisms scra: cycled core thf.n t.000 times. However, there

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,I vere so 1 ?ic tions that. cracking would davelop within the expected life:i=a cf 200 sera =s fo.r.the control :is.a: D csden-3.

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The collet: vich cracked'heusing ve.re replaced with ecv asse.blies. -

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Teture at:ic.,ns will be deter =ined by tha :: tee:C of tests new in pro ress.

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,,e 1.c prese::, Cereral-Electric r.ti K cente ::stional I.aboratory are co=Iucting f, '.

Independ*= =etallurgical tests to de:c:='ne the c::use of cracking.

. ~4*c 11though ic has not bacn rubstantia cd, the cause of crachir.; ray be reic:cd to the tc ps:sture cycle a centrol red drive czperiences during a reactor b'.

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.The' 2003 a.d 4013 cycle. sere:

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p. obability of to:al. collet ho61- <EIN* ***t. C.I. d: onstra:ed tha

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e qui:e rc o:c; The fu:::g,3,, j'_'_"fie barriar and is subject to

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CoMe: in a i In a rup;:erad possible vers: condi:ge.s a C,Y,~,_.8-

{gst s:3 sg=u, aseously, localised cc a d -. g..; gg.,,s ng ce::1.

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- ~ c 13--e: housi=2s ra : C frcs abnor=al Brb 4

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newe.)er[ ",*h.is this==likely evene,,

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,a rod pa: terns and power levels.

1{-. % liquid control systen vagig 1.e::a.n the reac:or in a s' utde.n co~~'~< ;---* all r'adi.:.a::ivi:7 vould be

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coa ci=ed with'.s the ta-o. vesse o-any there vo21d be no da=ger to.pl$'s:'p[:', ',. h 8

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• d Ucit 2 of the Poin: Eeach !?u 1'ea a

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~ "T'.ard trc 6 on the air ejecto'r rs P1 " ' ? *

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. indicative E'jd

'I.pri=ary-:o-seco:darysteamgaer[a-<o 2

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• f ary-to-secondary

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::e was calcula:cd to be 0.'3 gI a 3

02 SP:. but cparcting personnel hesa Cy e r t

• nor=al average of 5 ES-A anticipation of a blod own/shutdo.a. Five and cue-hal' h '

• Primary-to-second'ary

' {'N hf u k rate had increased to c.4 T"

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a the blevdeva conitor alarn was r'e$ei-

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an cre-half' hours I Ger. an ordarly shutdo s o 3'-@

s Subseque=t eddh* t ag. 2 l

• tat *'of approxi=ately

.i 103 !.'// hour.

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,~~',(*:: :: ide=tif ad a feiled tube' cu-in the "3" stea= gestrator. The ' 1 J

' h pha y of the N$.I C:

j tub: bundle sligh:1y above the to h,tI

• appearance of

7.cla:ively cleas cut c a rough 1 ircul-

~~1e indica ad a canufacturing "

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of da= age. folio.1 I e -

de t er the resul:

ture..

se failure appeared r?J to be randos in ua:ure and not co.nac e

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vasca3* in the kidsey' shaped hish heat.1= =:na of tha hot. leg.

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"h 1-ye iscovered to have.sik;nificant 8

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ec e L rd sgporg.- f,see,34,

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'vith a 53% defec:, vss loca:ed epr o.3 !.e17 one-inch ebe. e the sixth

D rupport. These tubes h

d - i ly bass Ou.e red vich a 20 to 30% defect' RY and a 40% de.f.ect respectiv 7 The failed de had naver been examine'd in N#.-

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Fogram,, Up cppeared to 1

c'itilit a loss of ovality o ater. The steam generator N T-s

'f I'3'*ft.::urer hss cdvised -ha CNShe of water on a N

C3Y'beacontributinkfact-

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"4 urable n=:a1 loss with loss f ov it

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Tha switch :n all volatils vater che=1::ry t rV..t=ent c: both I' its 1 and 2 j Y*

a pes:s to Etve inhihi:ed the tube vastage ; rdle: Previously discccared 8i;-

cew i=dicaciens of vastage in this heat ze:c vere cbserved during the

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in the kidney-shaped high laa: :ose of the srs.u: gesarator hot legs. No YU ing;e:: ion. In.sddities, although sludge dr;4hw of up to'four inches were

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t:sssered on the tubeshee: ty afdy curren: c:..10:: ion, this c1=dge ap V

r to he harco. *:us with the cubi=g. Sludge 1s.cing, therefore, was no pa:s f.$li peric:=ed du.ri=g this ou:rge.

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3 %/;l A se:endsry-:n-;;i=ary 500 psig leak tes:.va. ye fc::ed with satisfac' ory

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L'ith a rea:: : pcuer of ap roxi=ately 10% a: flait.No. 2 of the Erunsi.-ick

- j-Stea= Electri: Plast, the I" ccfety relief valve $cadvertently opened.

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Ad atta=p: to close the re~ief valve by placint, the control.svitch to

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clesa failed.- (A violatic_ of the een gency fr.ntructions occurired when -

th: raa: tor was to: manually shut down wh'en D, was detei=ined that the

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relief valve vas stuck in tha open.positi~en.).Concurren: eith attec;: to gF

.,h cast the relief valve', an a :e:pt was made to Jnitiate torus cooli=g i.-ith

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. c e of the residual heat re= oval 1 cops, but the service water supply valve Eff,"

4 to-the heat a- '-eger failed.to open. A redur.d.-=t loop was i=cediately placed in the torus cooli=2 = ode.

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Uhen theit decision was r.ade ':o shut' down the tv*eror, 'the'High Pressure E.f ~-

Coola== Inje:: ion (E?CI) o;srated for only a limited ti=a because'of high E,. Y.'

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torus level.. ~ an 1: vas a parent that =anual operation of the EPCI'could -

/.,M not supply clar.2 vater to

.e reactor, the =aja accam isolatica valves -

3 va're closed. "his action resulted in a rea:tur n::c=. Reactor press.::e L I"i i

decreased ra;f.ily,.and conti:ved to de: asse until the preszurc redu:: ion-

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I ves s:opped a: 72 psi by a;;1:ent seati=3 of ti.e relief valve. There was l

ro d:= age to :he torus st:.;sture or relief raive dis:harge pipes, c=d l'. rl I

int.paction iciics:ad all cc:; e.:s reacted nomally to the di: charge.

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l f:llure. A s;+:ific cause f : the blevde.. is! Jest was not discoverei.

l All relief valves ware actuated successfully at I'3 psi during subsei;usst

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re.ce:cr heatu;., and all relief vs1ves ce:

ce;n.ity checks suec,assfully.

c No problem vi:h valve opera: ion was identified.

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Seven days -Ic:ar, with the reactor.st S-9*; ; ve, and et E00 psi pressure,

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it was observsf that the ta=;erature of the dph:4:ge of the cr.=e relief

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t vr.1ve was aba =.211y high. "Ise relief valve was cycled three ti=es but i.;

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i did not ressat. 'A:.f a:ent valves were cycled i= an atta=;i: to shock close

.l the opas relief valve, h-.! ::.a valve still did not reseat.. Reactor pres-

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. s : n vss at 475: psi and decreasi=3 so the res===: vas =anually scra=med.

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I;urlag "the bicudova, several attempts were ca.in to ressat the relief.

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velve: once at IS*. psi, once at 82 psi, and' c=:e at 49 psi. Two and.a 1 e

• hours af:er the relief valve-inadvertestiy opened, the valve appeared 8,?f

,.i te resent s-ith reactor pressure at 20 psi.

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T e or three days prior-to the first depressu-^ a: ion, a ground alsr= had^

di ::vered in ther conduit for:the relief valve th:: had inadvers;ently ~

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.j b:.ca received in the centrol roo=.

The grou:I; ircuit was su'asegently opnad. A serest on the conduit cover had' pici =ial tha insulatica at the I '.

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j cc nectic: lie: vee: the,re==te cabling and *:he 'sim' enoid viring. The con-r.e::ics was reissulated and a 'c all burr en the end of.the screw removed.

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valve solenoid pilot operctors had been rebui1=.:, Upon entering the db.tell.

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gst: feen the first a:d recond de ; essuri:stion, ec11. Target Rock relief

.i af:c ' the second depressurizatien, the solenoid 'eparator of the relief.

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vsive that-lif ted vas found to be st'uck i= as fin c:=ndiate position.so F,.

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ic vss both blos.-ing air into tha valya air o;e:h. or. cad venti =i; air from.

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the cperator. /. secoitt grou=d was found to be..=:.used by vster in th'a fi,

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cc.lu..eid housing. caused frc= cendensation in thse-instrs= ant 'nir systes. ~

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The 1;;ound was re; aired and the air lines blow = dry';

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g-t.11 relief valve selenoid opera: ors.vfre rc==v'ed:', and duhing bench testing

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1: vas found the solenoids were i=itially er.er-fi:1ng ac'90 \\olts, but the

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v.-174 did not. d:op out un:11 a value of 6 to S volts DC and s.t.en al=ost zero A

'h:1ci=g currest was reached. These lo. values c:t hysterests cu.: rent could

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t.she coleroid. operation susceptible to spurious. ;;od:ds, laaksga paths, 7

or phs:tes cir cits.

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rive of the eleva: salen,o' ids were fous'd to have' thair 0-ring partially out of 5

I th:i cer.:. Eosever, further testing of the v:1ve solenoid cheved the 0-ring i.

~j ee- '.d be recaptured in its seat by conti:iusd cy dration (approxi=atelp i

t. s::) ti=es). A burr on the plungers centritn=ed to the 0-ring sticking 1: t's full cpe position.-

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1. sp*c:ios of the valve solenoids revealed all =n have dirt'in the body arv, at..t the lubricant use d to assemble the vatves had turned black from w.1v.: hect. Rust was 'found in several of the v=3ves, and at sc== joint's' -

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the tefIca tepe had deteriore cd.. Dire v:s f=rasad arcr.:=d the colenoid pile;. seats and plungers, and reven of the valva.:s had piston seat' 0-rings l

fu v..rlous steges of being disicdged fr..a thstr :acst=.

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nce solaeoid, v.1ves were cleased ad reasse bled with new bi>fy interna 11s -

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.d lubricastJ A leak chech of the vnives. indicated zero piston and.

.] 4 T:ppat seat-Ichage, but all ten +:.1ves had s==e pilot seat Icakage.

M:nr new pidngers were installed, pilot Icakaga was detected to be. com.i.h; i

.cou=d the pilot seat cud thre 3h ;orosity 1: tha valve h dy.

Sh valyy,

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vere made leah tight by.rese::h-the pile: sea:, cad four valves were 4-rt.*ceted be cuse of body porosity. ne latta: vara replaced s-ith new 95 valv.es.

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t lu eleve.s sols:cii v:1ves ths: passed inspe.::i:: vde installed and j

fen tionally tested satisfsetorily at 253 psi reactor pressure, and. ash l ;E

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at 950 psi a=120: power.

ne i=sulatics of the Targe: F.e k relief' v' lvas was =ed*fied to maintai=.:

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a ths air actus:or sad solenoid valv.as at a 1= var tc=pera:ure. After unit:

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.j sts: tup, the sele: olds were erating at less than 210*F, a te=parsture.

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ET.CISSIU FJ. ACTOR CCONSI.SYSEf CDOI.DD,;ti P.t.EE

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-. During the course o'f a routine shu:do: a for caintenance' of the ocones'

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~ 2:uelcar Stat' ion tait 3 vhes rea.c:or power had d.e:reased to approxi=at'elty~

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15.t. e.systen trensiest occurred that resulted in the' opening of a pres -

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p r.urizer relief valve.

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,;^ The power ac:us:ed ze ief vs1va had corred:ly opened when reattor cool::::-

i cysto:a pressure :[ ached 2255 psi.- but failed' to close when pressure dreppped I'

Islov 2220 psi./ ne ope /close lights in the cen::al roc = did cofi=dicente 3

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th t the valve was open! As :eactor coolant systes pressure drop;ad, ette I..,*

ru.: tor tripped on low pressere, nd the Hi;h Pressure Co:10.nt 1=jectics:

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-C" CIT s;ste. a::ua:cd.. Reactor coelas: systes ta=pera.cnte ah.d pressuree vsra 480*F and 710 psi, respec'tively; when depressurizatica terminated..

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.j n: 'initici. drop of te=perature exceeded the allovable cooldova rate oil 7

100'F/hr. by l'F/hr.

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ne relief valve was stuck open because 'of heat c:q.ansion c=i bo:Ie acidi,

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crysts1 buildup on the valve lever. The crys:als rubbed against the I.

solenoid brackets 'and bent the solenoid spria; bracket. ^ n e valve was repaired and reinstalled. Thr.: cause for ralf: netion of the valve positicon

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indication was not observed whoa the repai:ed valve was reinstalled.'

I' Fossibly, this =alfunction could have been caised by the solenoid plunsec

' sticking st slightly Icss than the full epen pesicion, or by crud buildupp-3

' crernd the plunger-operated cinature cont cl switch to the cpen/close

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..r nc transi=== a=f asse:La:ei e.s.:s z.lso c : sad :~ e quench :::k* rupture C{'

dlbe to bhu:, cir:c: i=s.:1stic to be separz:ed f:c= the be::c= nozzle o=

the pressc="i=ar, asi tha re* mass c: a;;;: '-=:aly 1503 call = s of reactor

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coolant to he reac:== h,'1'i=g su=p.

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ns release f es:1 =: did ::: c :sa r.=y ri;:ific:== ine c se of radiati :.

E level in thm = car.::: *: h;, asi r.o ralha::ivi.y was released into the

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caviro==act.. Tse-e=:sssive co:!de.= ra:e associated with tha tra=sient was evalua :ad, asi 1: vss da:arr.2d thh the c;arability of tha reactor

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s c 5 the hea._:h asi saf a:7 cf,de p.:blic vere : : affected. No other

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Lsile the p= var level was ice-assi=g a: r h 2, of the Quad-Oities Station 1

- af ter an cu= age, a:d with beth =ti= and hv fiev result. i=g-valves par:ial*1y J.

epsn, a fenc:vs:a: vibra hs a.12:= vas re:e'vad is,the control room. De t-u=it vas ca=- ="y s::a==af, feed.-ater p==;s vare : ipped ami the feedwater-regulati:ig :=:a.1== vas isolate.i. Es.2::or vnssel level was controlled with the Raaetor ::::a Isolatie: Cesihg Syste (7. 0).

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ne lov flovfeedvater'lise h:1 seYared a: a 6-o 4-Sch reducer on the..

dev-stream s:ide of the lov Ihv replati ; valys. Inspectie:s also revenla:E crechs in thse 1:2 fic. pi; h s a: the lev fiev riser juncties to the usin

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. feedvater " a a=1 is the rah e upstrea= of the regulati=; valve.

4 na initiaI =ause 'of c:s. chi =3 was eparatic:a1 vibra

• ions at. tha feedwater j

regulating s-.stic=,* a=1 the bret, was attri*:::ed to vi*cra: Lens at the j

ft.edwater re;;ula.ing sta lea deri=g tra=sfar of flov f:cm the low flov valve to thm -='- feedvater rez '--' 3 valva.-

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j 1.: no ti=e ut:s safe o;nrath: ef the rea::c threatened; r.11 reactor i

par =etars =es7saf e' sk:isfs::er'ly. ne :o:a1 :=su:: of v2:er released i

as a resul: cf this o::urren:a was esti=a:ed a: 12,503 galh ns: S530 I

.f-gallons frc=. tha severed 1he a I 4,c03 salic:s fros the sc vice vrk:r f,.

b sis, 'a:d st=:ivity at the relesse point in the dischar e bay was less.',1.

deluge sys===.

nis vater was dischs p! f := tha sito ou a batch contro i

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than tha 'IscP--4a*' Specificaties.li=1:.

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nc lov flaw: feef dter li=s hst failei ;;arisusly on June 10, 1974, when ti.: low ficu.* re;ulati=g velva ruptu:ed. nis rupture, also, was believed to hcve *oee:r. partly caused by vi'arstics dur'=g n::=21 rervhe, but the mais:

c:use was i=p cper es ' '*'a.g of the valva body for veld p cparation.

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s Cc:rective actions to prevent future recurre::a i=:1ude the instanatios

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cf a "4 rag valra" to' replace cas,of the cai: feed.sts: resc.1sti=g valves

'g.,

• Q, l

to provide mere adequate flow control over a -Idar rs=le cf flow conditions

=$ reduce f1=v induced vit::tions at the rag:*sti:3 station. Also, the 71.,-

i (Q

Icv flov :o t;:1 valve line is picanst to be :tpips.i. to a jes riscrous

. ::b 3

path as==othai =easure to red;;ce flow i=duced vibratichs.

t#'r:

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p UE?LAIC:ED T7"UE FROX 51~.~.:. Tw~:'DAZI

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-i Uith Unit to.1 of the Calvert Cliffs nucles: ?cr a: Plant at steady statie.

f.-f

, [,,:,.f*

conditicas at appror*- tely.99: pcuer, the co-trol re:, reteived a high i

. clarm fro = tha vaste area ventilation radicgis =2: iter. Tae.uain vente rafiati:s==:itor.vas also reading chave n=::al. Investigation revealed p,.5 j

ge.secus radicactivity s:as being iceleased to the auxiliary building venti-

, j;j.

W 'l,:'.

lation systen.

. < u-I ne radicactive gas vais 1cahing firo. a vaste g' a ec=pdessor and frc= the j i,V

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volu== control sa=ple hood. The valve had c t been co:pletely closed-a ff",.

j't -

foHwing sn=pling.,anoving leakag'e' throu;h-a secti== of. c=cessively -

lp.!,..

9 i

parferated sur;;ical rubber tubing into the pr -- y sa=ple hood and.into e

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vested ths vole =a control tank vapor s; ate to the vaste gas system..

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.i the vaste crea 9entilatien syste=. This c:used the =c:itor alarm a=d also

'h' i

/.ppro.ki=2tely !.5 Ci of Xe-DI and 5 Ci of Ie-U3 vare released during ths.

l[

incident. This'. release is less than'12'of the Tech ical Specification relcase rate.1-i=it for noble gasus. Tuo iciividuals were slightly cc a=-

j),.,,1 insted shile i=resti5ating the source of gase:us activity, but, they were -

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restily and cc:pletely decosta=inated. It was cc :1uded this incident 41d cot constitute an undue hazard to the. health asi safe y of plant person =e3. -

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or'to the gesaral public.

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1 T..e section of

.r T?ie diaphra:s ' f the vast'e gas ccepr'essor was repla:ed'.

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surgical rubber tubing on the volu=e costrel. ::k sample point, which ha.i ne g,

I been repeatedly perforated by the gas sa

p11:3 s.y:inge, vas replaced.

inpo:cauca of =caularly repir. ing used saa sa=pling =ambrensa sad tubing, y

l ced cf preper =peration of se:ple systen vajvss vas c=phasized to all pl.=t

{

r:diation safety and chemistry. technicians.

.}

RELEASE IN EXCESS OF TICF.::ICAL 5?1CInCATION LD11TS 4

j over a period of several vaaks, contain:&nt structure intems1 pressur's gradually ineceased to 0.9 psig et the Calv.:t Cuffs nucles: Pova: Plant f

g i

U.*it 1, s:'d it was decided to deliberstely vant execss contain= ant pressure li l

to.the at=u.tphsra.

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1. imd os radiose:ivi:y t.sature:ents of tha cen::imas: a:=osphara, a F ':

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rc.s5= release rate of 49,553 cf: vo=1s cc:::e cc=; Ia ca s-ith'T=:hnical

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specifications. Using the 'contai==an: purge fa=, rate.f at 5*),000 cf=,

iz j

vould have resulted is the ellevable release rc:a be.f 3 cxceedad, so it 91 l

va: decided to vast th:ough the contai=ar.: ; urge isc~2: ion valves without 4

operati=g the f ecs,.

Thesa valvas vare operst fer fou= minu:es,' and con-

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tah.: :: pressura dae:aised to 0.05 psi;;. I.sviw of preseuras race: dad lls?

i

-l dari=3 van:iss indicated the at:ual ralassa rata' to hs 51,303 c!= during i

t1.2 first ci=:a of vasting, exceeding the li=it by 4%.

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. It van esti=atal th'a reiaase rasulted in los teas 5'=* *; 3 cre= to as

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.I individual at tha si:e bou=dary. Therefora, this i= 5.iant did not constitu:a j

an und'u'a hazard to the ganaral p.plic..

0

,'.4,$

I'm ing future.contai= ant vasti:gs,.' either c:a of the y=:ge isolstion '

' valves vill ba throttled. of as citerus:a =ea=s for 'c=:a slo 217 vestins 1

tlie c..entair.: des: vill be providad.7 a

s TT.AN3?IA DE REITILr:0 E*CfR TO CC1: TAI::MI::T IJ.SE2E'.:T'-

'd..

Dark: ps:for=ance of a periodic test for safatuard s rsta= valve operation at' Unit.Ko. I of the R.I. Cima I:cclear' Pova: Ple :, a 'flev peth from the rehali'23 vater storaga tank.(Er3T) to.the c:stai=ent was inadvartently

,1 estr.b11 shad, t.sd. contai==est is:=;ri:y was vicla:ed.

f

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As cperstori,whil'a folloi.-ing a chechshee:,' c1csed valva l'.0'.*-8513. and I

errinnously. reopennd it. be*cra the next s:cp to streks M3V-E503 'and.1.

^

i.ti:islad the p :cedural step "close 1:07-3511". He the.: noted i: vas time (i.

ic: his' hourly readings and requestad smoths: operator to take them.for

, f'.-

Li. Eaturning to the.procedu a he'saw that the next step a.fter the last p

etep ha had i itialed was to epaa t' i-3503. Upes tha cpienit; of 1:0V-S501.

vich 1:7.'-8513 eran, flev was es:ahlished fro: ths R*i3T to s,c. p 3.

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.p'.

i U.len receipt.of ' alar:s, the operstor i=ediately secbed ths *1=v path. '

g,

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.p' fi. vas as:i=r:sd contah=ent had tasa vioisted for a;;;:7.i=stely 3 cinu:es '

p-j

t..d :. bout 12,C00 gallona of refueling water vas e :nsist ca t'o con:ah:+nt.

g,

%.cre were ir.dications that appror.1:stely 1-6:h of v2:sf had tsei on the

t.

centair. rent floor. No dana 5a to tha caraguz:ds equip-4-t was noted and

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the utter was procaszed according to no=al. 7:ocedu as.

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'Ais:c was no dc ger to the plant'or to the ' health and ::fety of the public..

i

}

~ Ti. control reus oparator was reprimanded ard, because of the noturo of I' i j

thf t cecurrence, precautions have been i=ple:ented so that control room 1

i+ r.onnel vill not have simultpeous respcnsibilities reistive to nortsi htics cnd reutine operations.

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"~7 5J U: F.Iqr17.ID ACTCAIIO:: OF EY..p.0I:;-i ETSTIMS d

=

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cith 17:i= ro. 2 of.the Millstone Nuclear Peve 5:stien in the power asce:sion ch.e cabir.at for channal ' C" of the I:;i:urd Sefeguard: Acti:::1:=

f

phess, i

Systc= ('. J*.AS) ves deenergized fe:E caintess-ce. ;.1 other cafeg'ua:ds i

I'

'chr.ri.al: s. era energi:ed. The techniciz=s perf:::i=3 the esintenance thss noticed the positive logic power rapply fuse ligh; for ISAS channel "D" v:s cc:; :his 'condi: ion was ihdica:ive of a 11:. : fuse. The-fusa indice:or i

The fuse vas theh i

lish: b.Cb was replacad, but the bulb did not e.argize.

I.

'I recoved, resulting i= a loss of channel "D" IIAS svar because the Ihse

.j -

vac act" '"y not. blown. 'With chassels "C" a:d "C" descargized a 2 ~out-of ? logfi: cc ditie-vas establishad, resulti:3 is ge:eration of all-i

~

. I c ineara.d safeguards ac:uation sissals. This i=:1uded the loss of the j

i ner=.11 j:= war sis =:1 'an,d causad,bbth diesel genera: ors to start, s-ith load-

-lU.

shedding;=o occur from the a=argency buses.

-i

.1

^

h ne actu=: ion of 'the ESAS c6= pose Es did 'not afvarsely affect the rest of-6

'}

the p1:== or 'the he,alth and saft:y'of the public.

.?.

As a restct of the ISAS transie::, it was di' tovarad that a blo. i fuse of e s

-.(.

a'po-sar :.upply fer ae.:ccatic class:e of c,e of tha diesel generafora ento I

i an c:sigrus y bus was ti:darsized. Fevar was t:a:ailable to this bus :for a P riod c" about 12 minutes. l i

=

' The 3" s.ervicai. vater pkp failed. to star:. i.ecav.se of, t.n r2=inistrative

~

error, thia Pt. p was aligned to I:it 1.

A viri =g er:cr was subsequently l

d'iscove: ud in th'a water pu=p cc trol circuit tha: prevented proper seque==ing a

of the s.urrice water pu=p,.

l f.lso, tub of the centsin=ent cir'erecircula:i:= fa s did not. start en slow c;>e ed.

':-he p: chic = vas traced to a loose re":y.:: the control of S::h

.fcas.

.l All cf the discovered magfunctio:s vera repaire? z=d tested to verify their co=:ect operatics. -

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e I

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j e

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t

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r.~w.-='=--.-.O==*-*~~.**

-===.-n--.= g n-.- -

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7. g 7 q

o. 7 2..:e s.

.. +.-..--. g Lu e,

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8. J:

.h 1

t. U.

j t u.f.

S

'I

.ti.

i r..

.J I {a(.9:

i }'..b' EE}MCES.

3 4, Lr. o. 2 1

o 1

!. : ~

f 1.ce:er, t.E. St.cphenson (Co=onwealth Efison) to J.C. Keppler, USNRC, g

Ofiiec of Inspection and Enforce:a:. - nesion III, July 3,1975. Aca

'{./.

1.

No. 75-31. Do:kat No. 50-249.

.-!.:'s ;

- f n.

y

?

~i' '

I.et :er, S. Eurstein (Uisc== sin Electri: Pever Co=pany) 't'a 3.C. Rusche, 7 @y.J.~

j 2.

U5i:TN, Office of **uclear Esactor Iesclation, Septe tar 26, 1975. Dockat'

1. c,

s. 30-3&L.

ns:.

[ % y 3.

Lot:ars, E.E. Utisy'(Csroli:2 Powa'r & Lii;ht Cc:pa=$)' to N.C. E:seley, n h@

US'C:::, Of fice of 1 spection cud Enfo:ct:ast - Region II, May 15 sad

',.t 21,.1975. AO?. Nos. '75-13 to 16, Docket No. 50-324. -

W,

... ;W.[

i 4.

Let:ters, W.D. Parker, Jr. (Duke. Power Co=pa=7) to' U.C..Eoseley.USNRC,,

Of f.E:a.cf Inspection cad-Enferce=t.at - Rc;; ion II. June 27 a:d Au2ust S.

- N.J.

.; {g.,

1 197 L ACR No. 75-7, Dochat No./50-237.

..s i

5.

Lcteer, N.J. Kalivianakis.(Co=onver.1th Edison) to USNEC, Director of

' b,c.-I6 "j

Offt. a of Nuclect Reactor Regulatics; *; gust 27,1975.. ADR No.,75-31

• [$.

n f...

vechat No. 50-174.

p-o S.

Le: cr, A.E. Lunela11, Jr -(Ealti= ore cas and Ilcetric.Co:pany) to

]L ?.

g

.f J.P. O'Keilly USNIC, Office of Inspection cud Enforce.sent - Region I,

};G.'

l8 July 28,1575. 1.0R No. 75-44, Dochet No. 50-317...

If.

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Let er, A.I. Lundvall, Jr.- (Ealti=: e C:.s and Electric Co=pany) to

.h..

.t 7.

J.?

O'T.eilly, US5?.C. Offi'ca of Inspection and Enforce ant - Region I,

. f(p,

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.)

Au;;.:st 2,0,19.75.

A02.No. 75-48. Uc ket No. 50-317..

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..l 8'.

Le==cii L.D'. White, Jr. (Eccheste-Cas cad ' Electric Corporation) to"

~

j-J.?. O'Railly, USNKC, Office of Inspec-ion and Enforce:ent - Region I, j...

{

Au;;=:.st, 22, 1975. AQR No..75-13. Docha: No. 50-244..

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I.et ar, W.C. Couasil'(Northeast Muelca: Energy Co=pany) to J.7. O'Kailly.

9.

L

• US;;T.0, Office of Inspectie.~. ced Enforca. cat - Regies I, September 18, 197 1 /.02 No. 75-17, Dochet No, 50-335.

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