ML19274E781

LER 79-031/01T-0 on 790412:during Routine Radwaste Release, Release Monitor Went Into High Alarm Because Radwaste Isolation Valves WDV-320 & 321 Failed to Close.Caused by Sticking Contacts in Monitor Bypass Switch

ML19274E781
Person / Time
Site:	Crystal River
Issue date:	04/17/1979
From:	Cooper J FLORIDA POWER CORP.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
Shared Package
ML19274E778	List: ML19274E777 ML19274E781
References
LER-79-031-01T, LER-79-31-1T, NUDOCS 7904240403
Download: ML19274E781 (2)

Text

-

g 0 IMilISfi: qW h:3 .%. ,)il 3:

f

,$ ];

WO dU U uh',[;N; L  ; M.b U. S NUCLEAR REGULATORY COMMISsiCN NRC FORM 364

• EXHIBIT A LICENSEE EVENT REPORT i

CONTRoLsLcCc1 1 ! ! I i 1@ (ptcAsa PRINT cA TYPE ALL RECulREO INFORMATIONI 0 t 0 I- t 0 l 01 0 l Oj0 110 ; 0 lg 4 i 1,1(1 (.aj1 gu .- q gu g o i lF 1 LI QRnPt3Igla vens..c;a, ,. v.w.~-.. a ;6 m . m. ...

CcN T oIil ,j[j"j Q1@l 01 5101 -t0! 3l01 2 GI 014twt I%7112 w 69 3 aft I 71 o@l0mE*Omfaart

• ?$ la 11 1 71dJ 71 o I@

64 68 COC4 ET NLeg ga J 4 svENT cesCRIPTICN ANO #RC0 ASLE CONsECt.,ENCE3 h 14-.,4 At 1000, while making a routine liauid radi, tion v,sen -olo,cn *ko 4  !

., ,; 1 r,A4,*4 z,c*n I -

, radiation release monitor went into hich alarm. Licuid 0n

<c  !

g,, g isolation valves WDV-320 and 321 f ailed to close. Tbfa - , - - ,

Environmental Technical Specification 2.4.1.D. Redundancy NA. No safety 1

,>1, l l

0u thazard to plant or nublic as ebo --n < . , -y , 1: 1 q_.,__ f, , _

, values specified in 10 CFR 20, Appendix B, Table II, Colunn 2 fo" ""-an*-i d ed

,,, i areas. Quantity of activity released estimated at 16 nri . Ntk l 4 3 Cov8 vai,vg 7

$*171M CawSt C4.5E SLeCO f ILe000E C001 COCE SL300CE CovPCNINT OODE assi I MICl@ .a ,,

g @ W @ ,l11ylq17Nlpl@ W @ mg @

47

• E' iS'CN

, . 0;;;as(NCE 18 8 -v 8 8'.s so

,avnTviaa at 0.b carl% .aT.l a t :cOc a

l 0 l 3l3 l y in I , l [gj (_, _,,) [g,j

@ sa5;s;" ao

}7 I9 l [_.]

22 ;s .6 21 211 49 JJ Jr J2 25 .

VAN sa T p(m

= Oval 5 9 fos 3 $ sol E i - I r' CN*LANT T N 'aYTIC 7

E.J@ljuG t.1J@ L.2J@ I n' v

d^tl W@ sa s.

L.2sj@ LJ@

l u as 4@

u :s s ..

cAusa ces:Rierios Aso OcRRe:n.t AcTiess @ I

,*t-fk,. ens -

i ,0 tThe apparent cause of this event has bee, --4 49 .

within the radiation monitor by-pass switch. The bv-n,sq ez4*-k -, ,--- 1 Func.'onal checks were na-fnr-oa *n n4c' 1

, pere cleaned and lubricated.

1

, , proper switch / interlock onorabilirs- 9, -nc,,----- --

~ , - . . . .mm.

4 Et 5 9 F

go C5 4 0 5:Os f av OE5Ce+87 ON

$? '  % eawga Otute STATLS y U@ l017 l 3l@l MA l W g'l Operator observation- "

l

' ac'r.s,T, C: dis? LOC AT'ON Cs aELEa3E W av;ys? cs a; wiry at tl a51 ,

i EE U @3 Os ag. u I i t,3 gastz!@l go 44 at 1t 7 e 9 Plm50N%Ei,E58046*t5 svvege +veg ts;a svecy l

l0 l 010 T@(z,,j@l y i

> - * ..., ss,a .i.,

Nsv9te O f 50R '**'CN j 101010f@l i i; a

.. i:

r

'. 0510 8 O s c av a g g 'O s aci . ?w

'**1 O ti.* F*tCN y

T go F 8 9 4 Nac vsE c'+Lv I iiiiitiiii'if L.:_LJ. W. Qe'i5;a ,,.os@ I ea A

'j 4

' J. ce , a - . es: _,_,(304)795-6486 N2..s :c e.g. Ap an _

/'

790424 0qD3 ( E ATTACHED SUPPLEMENTARY DIFORMATION SHEET)

• • p*Nmg6

SUPPLEMENTARY INFORMATION Report No.. 50-302/79-031/0lT-0 Facility: Crystal River Unit #3 Report Date: 17 April 1979 Occurrence Date: 12 April 1979 Identification of Occurrence:

Automatic closure of radioactive liquid waste isolation valves did not occur contrary to Environmental Technical Specification 2.4.1.D.

Conditions Prior to Occurrence:

Mode 1 power operation (73%)

Description of Occurrence:

At 1000, whila making a routine liquid radiation waste release, the liquid radiatiot release monitor (RML-2) went into high alarm. An immediate check to assure interlock actuation revealed that the liquid radiation waste isolation valves WDV-320 and WDV-321 failed to close. Actuation of the bypass switch several times terminated the release at 1001 with the closure of WDV-320 and 321.

Designation of Apparent Cause:

The apparent cause of this event has been attributed to several contacts sticking within the radiation monitor by-pass switch.

It has been determined that the contacts remained engaged without indication following the completion of Surveillance Procedure SP-335, Radiation Monitoring Functional Test.

Analysis of Occurrence:

There was no hazard to the plant or general public as the one minute release did not exceed the values specified in 10 CFR 20, Appendix 3, Table II, Column 2, for unrestricted areas. The cal-culated release rate at the point of discharge was 3.2 E-4 MPC's as determined from a 30 gpm release rate. The quantity of activity released following the high alarm is estimated to be 16 pCi.

Corrective Action:

The radiation monitor by-pass switch contacts were cleaned and lubricated. Functional checks were performed to verify proper switch / interlock operability. No recurrence on subsequent releases.

Failure Data:

First occurrence of an event of this type reporten.

/rc