ML20236F536

Safety Evaluation Supporting Amends 61 & 53 to Licenses DPR-77 & DPR-79,respectively

ML20236F536
Person / Time
Site:	Sequoyah
Issue date:	10/22/1987
From:	Office of Nuclear Reactor Regulation
To:
Shared Package
ML20236F523	List: ML20236F519 ML20236F524 ML20236F536
References
NUDOCS 8711020194
Download: ML20236F536 (4)

Text

?' >

l.$

<~

^

'W, , , My Y, 1F , y :)

';Whg  ;

Q:' ,

. . . f ;!

4 Q Q.

[ ,

LUNITED STATESi 4 O

M, ,,pp";- fg - NUCLEAR REGULATORY COMMISSION. M

,' 2i : s WASHINGTON D. C. 20555 - g 4

....f , +

,y t

7, ((

_j T. ;

,M if)

I SAFETYEVALUATI'ONBY'THE0FFICEOFlSPECIdLPROJECTS' I W

. .. . . . . y .

fmE y d

SUPPORTING)AMENDMENTNO.61i:TO'FACILITYDOPERATINGLLICENSENO.DPR-77!

<W AND AMENDMENT NO.L5'3H TO FACILITYt0PERATING LICENSE NO.?DPR279) c <

[ >

iTENNESSEE' VALLEY AUTHORITYf' ,

4

,i , .y<&y

.x 8

.. m9 W' *

SE0VOYAH' NUCLEAR Y PLANT UNITS J 1 AND '2j ' '

W. _ 4 . . ~

DOCKET N05.:50-327 AND 50-328. -

n , <

,  %> t pa

, l

1.0 INTRODUCTION

- '.). _' '

( '

E if 1 Thissafetyeval'ationaddressesproposedlchangeTVASON-TS-87-29ntobequoyshf['r. I u i Technical Specifications, Units 111 and 2.SSection 3.8.3.2;OThe:changefinvolves: '

'periodic deleting.surveillance and ' adding ;specificf motor-o'perated Jvalves f(MOV)(TOL)!from(those. .",

re testing!of their thermal overload l protective .

devices. In~a: submittal dated May115,11987, su -

June.16,1987, Tennesseef Valley Authorityf(TVA)pplemented by?atsubmittali.~ da proposed: deletion?ofEthree c

categories of MOV and the: addition of one categ'ory toltable' 3;8-2 LofJthel !

Sequoyah Technica1 Specifications; 1Section 3.8.3;2 of the' Technical:Speci-j >4 fications require that TOL'! devices for the;valv_es1specified in?theltable' bei operable, that the operability of thejT0LtdevicelbeMemonstratediperiodically L ,

l and :that the assocSted valve be declared 11noperable:when the?TOL of the! motor?

operator is~ found !to se inoperable. . The individu'altcategoriesi of MOVtaffected t by the proposed Techiiical. Specification change'are?as;follows::

, . . . . , . . r. ...

(1) M0V's'whose TOL device isLto/be permanently bypassed:andithsreforeTto!bei L

deleted from the table (Attachment 1;to 6/16/87l submittal).. ' ' .

-(2) M0V's no longer required.to be activ'e '(to change state.in normalloperationf or during accidents) as a result of changes'in proceduresf orfsystem,~ .. X ,;

configurations ~ arising out of compliance with Appendix;R 'and< therefore' to , q be'deletedifrom, the table' (Attachment 2 to 6/16/87; submittal) " q

~

. . , .i ,  :

(3) Valves not required to. change 4 tate to prevent or mitigate an accident;; .

J consequently.not required toLb$ tested under ASMELCode Part'1116Section 111 ,

.i

.andthereforedeletedfromthe. table,(Attachment 3toL6/16/87Jsubmittal)'3 . 0

. . ., m

4) 'Valvss with TOL.devi'ces . required!to be operable andl inadvertently omittedl f rom the techni cal : s peci fi ca tions [( Attachment l 4 ito 6/16/87; submi ttal ) . ~

J

'[. l

',yj

n. '

3 , , s; . m

. ' q. ?; , , g 8711 1 Y '

, l.

• w <

7 f 02019'4< ADOC OR g' K ' 05h,.*J2d a, r

e

$ '4' 5

, , ' ,, N y a ' ' '

L +

, b %y y'

P x

, n. ,

u

&' y , M( ,

w.

q' >

cv,y.  ;; ,

w a~

a g. + pm -

,m y Wm

• jy ', 'e * \

O-( I , #  !

Ed;.{ &_ a c' s . "._.; '

• L' yu h

^

1 (l{

&m 4 > L_v. 8

.e , .

m., .,

a "

, .jl 31'

~

p.j , -.3~.

' , ji (f , ,

[ -

M u

,3 , '

r .(

g.

- ,l

A

,  !!i 1:

m q

2.0 " EVALUATION x 12.1.'M0V's with Bypcssed Overload Devices ~ , d,

~ '

DuringanongoingreviewofelectricaUcalcu1'ations.TVALdiscoveredthatltheJ original voltage drop calculations for Sequoyah's' electrical system-did not' +

' take into; account the voltage drop at motoreoperators caused by the. TOLo . . 4 <

-device in series with the. individual motor.' .When:this?effectlwas:consideredh

'the recalculated motor terminal voltage was. unacceptably low during.certain-transient loading conditions following;an1 accident? To: correct the situation,-

~

TVA proposes to bypa'ss. permanently the TOL devices :for the;affected valvesi O

, m L

TVA. notes:as' justification, NRC's Pegulatory Guide 1.106 which'in paraphrase 1 states that (1) TOL during testing.or b). devices should be'either a) continuously bypa to IEEE-279.or (2) TOL devices be set.with 'all uncertainties: resolved in the? '

H direction of ccmpleting the safety? action', 'i' e., set high',L an'd periodica11yi tested. TVA further. states that, given;the high set t point on1the1TOL devices' being bypassed, i.e., locked rotor current, there"isilittle ~ benefit to rein-1, j serting the TOL . devices during valveToperation fo'r testing 7or; maintenance.s ~ l The TOL' device provides two functions:.

'~

(1) It pr'otects the motor in a lock $dI rotor condition. y >

It may detect by tripping during test progressiveldeterioratio:f of ? 1 (2) the valve.or operator.

TVA has reanalyzed the circuit breakers associated'with the: motors t'o" assure; they will: provide locked rotor. protection 'andlwhere necessary hastreplaced' ..

o breakers; thus TVA' addressed the first function'.' ,TVA:has7 institu utility industry with NRC input to detect deterioration.r [Further, at the next :/  : j~

refueling outage TVA will: implement a= periodic main.tenance' procedure that :

will' measure alltphase currents'of the MOV's during testing.-1This' procedure 1 i'

provides a"second means.'to~ detect defects intmotor operatorior yalve. 'The, combinationoftheseclattertwo; programs; addresses 7the~secondfunction. . .

j A review by the NRC staff and its t.onsultant of these programs supportslTVA's'. ,

a conclusions that the M0V's are adequately protected again.st electrical: fault orLlocked rotor without the'TOL:deviceland that: bypassing of the TottdeviceL ,

will not' degrade system,or plant; safety. Fu rthe r,1the MOVATS ' program' wil la  !

provide an' equivalent:and ~withithe'additionLof. periodic phase. current measure-ment ;-ia. superior means of detectingLmechanical'or electrical Degradation 3off "

the motorf operatori or valve.; ;ThereforeW the MOVATF program' provides f aireason-J ,

able justification'for; not removinghthe bypass feature during' periodicLtestingh

' ' ' 4

<The possibility lthat the TOL: devices woulidete:tlelectrical' damage during:

. testing:or2 maintenance,Cduringitheidevelopnent~ period:of;thel phase current % _ ,

4 p'g m , . monitoring /resulting in faultKcurrents thatLwould.notttrip;theffeederzbreaker, ~

r

> "' M.7

,7' s 4

Lis[ consideredL too remote to:.requireiremovaliof!the; bypass? , .u v";

^; "

^ ':, ' s, h ( ' , . . ;f ' gg ; y 4

~

e y , , ,

,Y s p.- s .

g 7 ;j 1

I

/

, * ,c)

- 3. c .

0

l

~2.2' M0V's Deleted to Comply with 10 CFR Part 50', Appendix ~R 2

d A total of 10 valves are-deenergized at the' switchboard to conform to: Appendix R; , 'j requirements. The only. time they will normally?be1energizedlis: momentarily l for position indication'.:11f:for any reason the valves are energized for over : -,

l an hourk a fire watch will. be stationed.

Therefore, TVA" proposes deleting the '. -

TOL. devices for these; valve operators from theioperabi_lity ~ test;requi.rement.; lThe ' mj NRC staff and its consultant concur.

j 2.3' Valves not Required to! Operate to Mitigate Accident's t >

j L

Section XI of the ASME Code,.Part III requires: operability testingiof. valves l- required to change position'to mitigate an accident. This. operability testin.g4 '

requirement includes testing'of the TOL'. cA review by.TVA has ide'ntified116 ' , H valves previously included in'this' category that:are actually 'not required l l i

to change position. Eight are safety injection: accumulator valvesLwhich are l required by procedure to be deenergized'at the switchboard!in'anfopen position:

during operation.; Eight more arelvalves in the Essential, Raw' Cooling Water ,

and Component Cooling sptems which do not enange position 1during"thenaccident;. ,,

and'are used to provide flexibility in operation:or maintenance. 'The staff and. g I

its consultant agree that these valves,.not being: required:to: change position 1 in an accident, need not have-an operability test requirement)for. theirc. TOLD devices.;

2.4 ' dditional Valves ,, V d

i TVA has identified 20 additional valves whic.h,'since they'are: required toi 'l

. operate for. accident prevention or'mitigatioce need'to have their'TOL' devices added to the list in the Technical Specificati ws. lThis'is acceptable to NRC 4'I

. staff. <

L

3.0 ENVIRONMENTAL CONSIDERATION

Theamendmentsinvolvechangestorequirementswithrespecttoithe[ installation '

-or use of.a facility component-located within'the restricted area a'sLdefined in 10 CFR Part 20 and changes to surveillance l requirements. The-staff has deter ' .

mined that the amendments involve:no significant increaselin the-amounts, and

no significant change in2the types.cof any effluents that may.be: released-

.offsite, and that there is.no significant increase:in individual:or cumulative >

j occupational radiation exposure.gThe Commission has'previouslyl issued'a pro c ji

< posed finding that the' amendments' involve no significant hazards consideration

.and there has been no:public" comment on such finding. :Accordingly, the: amend ' ,

i

'ments meet the eligibility criteria for categorical exclusion set forthlint10; E

CFR 51.22(c)(9). ePursuant!to~10 CFR 51.22(b). no" environmental' impact;statei '

9 ment not environmental. assessment need be' preparedtinfconnection'with!thc;

~ ' '

l

~

issuance of'the. amendments.- -

y 4 L=_ _=_ r =_ '

4 , 8 . c

, m.

i

i.

^~

,, ),} 1

,i 3

I m

(:l 1

- 4.0' CONCLUSION- ,

l ,

- Based on reviews by the staff. and its consultants, the . staff'concurslin ' he1 t

deletions and additions to1 Table 3.8-2 of the-Technical Specifications, Thel NRC staff notes TVA's commitment toLimplement a M0 VATS program priorJto .

restart of unit 2 and implement phase current monitoring of:all MOV's:(both those covered by the EQ program-and those not covered) during the next : C refueling outage of Unit 2 and. prior to' restart ofsunit 1.-

i

' . . - .1

~

JWe have concluded, based on the' considerations discussed.above, that: L(1).there l is' reasonable assurance that the health and safety of"the:public will.not be i endangered by operation in the proposed manner, and-(2) such" activities lwill. 1 be conducted in. compliance'with the Commission's regulations..and theLissuance H of the amendments will not be inimical to the 'conson' defense and security nor to 'j the health and safety of the public.' j l

l Principal Contributor: Edward-F. Goodwin, Thomas'SE Rotella j O

l Dated: 0ctober 22,'1987 q

~

u

'j l

. i. ' )'

4 3

l- .

I' a..  ?

-_--___ _ . - - - _ _ - (