ML18008A082

Worcester Polytechnic Institute - Issuance of Order Modifying License No. R-061 to Convert from High to Low-Enriched Uranium - Amendment No. 10

ML18008A082
Person / Time
Site:	05000134
Issue date:	09/12/1988
From:	Michaels T Office of Nuclear Reactor Regulation
To:	Newton T Worcester Polytechnic Institute
References
NUDOCS 8809190267
Download: ML18008A082 (29)

Text

\ '

.*.:Mr. Tht:>masH.;*New.ton, Jr*., Director*

. Nucle!fr Reac,t9r fa~ili.ty' .. *

'Wofcestef ~olyte,Chnic lns'titut.e *

• . Worcester, Mas sachlise~ts 0.1609

Dear M,

r. Newton:

susjECT: isstiANCE **oF. ORDER MODI FY.rNG. LICENSE NO.* R-61 TO CONVERT FRO'M ,'HIGH TO LOW-ENRICHED URANIUM--AMENDM'ENT NO~ 10 - WORCEST~R POLYTECHNIC.

INSTIT~tE . . , . .

The* Commission has itpproved an or~e~ modify.fog Fa~il ity Ope~atii,g :L fcense .*. '.

• No~. R":-61"'.-Amen~ment No.: 10--for the. Worcester Polytechnic Instfti:i,te Tr~in.ing an~ Reactor fa.en ity ~ Thff Ord.t!r modifies the li¢~nse iri accordan,ce ~i th *the Commission's r:ewlatie>n$, 10 CFR. 50~64,which r,eq~ire.that.a,non.:.p1:>we.r rea:cto*r

. such as you.rs tl'nvert .to.* low-enr.iched u.rariium,,(LEV) fuel ijrlQer* certain. c6n~i".'

.tion*s. The O.rrler is being i)sued in accordan*ce ~it~ 1p*cFR: so.:64(<::)(3) and in

.

• response ,to your s.ubrofttaJs dated ~epteiit,~r 17,> 19~7 and: 'February: 10,. l~BB~. .

While the~~ .submi Ha ls* cont.ained the* ti~~,~s~ary jnforrnati.on *for tis .t~' approve

• the tonversjon ,to. 1.w *. ~e found that some information shQt.ild b,e corrected arid cl~ri.fied for* the rec;ord.* *. Please. re~pond to t.h~ st.atement~. in .EJ1closure 4 *in.

. .this f'egard *within 30

• d.ays **after* rec¢ipt of. this letter or a.s indi<:ate.d by *-the

• . statimeht.

. t~*e Order wfl lbec'ome *effett.ive tin the later da,te .o*f ,either *receipt of. I.EU .fuel*

. elenie*nts or 3*0 days follo\tdng the date of publication of this Or~e.r in the*. . :

• .*Federal.Register,* provi.decJ there are. no requests for a hearing. : If a hearing *

is r~que$ted the Order wi.11 bec.ome effective on* thE! date specified .,in an qrder

.. following further ptoc~eding*s on. this Order.~ Please i~foriTi- m.e when Y,CH.i receive

.the LEU:fofl *elem~nts arid ~he~ the.HEU will be completely*remo~ed*from the facility. * *

• * : : * : * / , : ~ *. !,:..

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• ',, ,, i . J ** *2~ ,. , . , * *,~ f;1/ *.

• New,tcm*.*.

Enc fosed w1 th the.* copy of the O~d~r w.hich 1s b~ing sent t9 *the. *F~dera t ' , * ..

• Reghter for p_ubricatio'n is a copy of the Safety Evalu.atHm and rep1acemer:it:

. pages for th¢

. Technical Specific~t1on~.

Sincerely, Theodore s. Michaels; Project Manager*

Standardiiation and Non~Power .. ..

• Reactor P~oject D1rectqrate ...

D1v1si6n of R~actor P~ojetts - III, IV,

• -V and Special Projects

• Office 6f Noclear.Reactor Regulation Enclo.sures: . .* .

1.

• Order or *Amendment No. 10

2. Replacement pages for Technfcal Specifications

3. Safety Evaluation * . .

4. Information to be supplied by WPI .

• ct: See next pJge

• DISTRIBUTION:.* Docket Fi le

• TMurley/JSniezek *rnfraglia EHyJton **

• TMithae ls GPA/PA * *

• wLambe; PTSB .

EJorda'n DHagan . .. .

• Hearing Lawyer, OGC JSc1~to~.OGC~Rockv1lle.

Nttc &*Local PORs DNash' *PTSB DCrutchfie id LRubenstefo PDSNP.Reading ARM/LFMB ..

• TBarnhart ( 4)

• ACRS ( 10)

ID1n1tz, PTSB JPartlow

!Bailey' -R~gion I PDS.Nl.-

.* ... . . PDSNP ,./~\ . Ap: PDSNP~~*

.E~on TMich!els:cw CM 111 er ,_,...

/J l'ID/88 7 /J.o /88 . -1 hl, /88

• ~;fi)f1

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....:Newton-.::/.

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• i.Mf~---:.ThO.maS-*:H:

.** .. . . . . ' . - ~ *' :-*. ' . . . : . ~* ..*' . *: ... '* .

En~lbsed withthe Order, Which is being sent to th~ Federal' RetSt~r for, ,

pubHcatfon, *.1~ a.c_opy*of.the-Safety Eval~ation and replacemen pages*for**the Technical Spec1fication~. - -

• .:

• Si nc*ere\y.; '. **

original signed by .***. - . *...** *.* . * * ** *

. Theodor!:? ~. Mi.c~ae ls, ..ProJeqt .* Man~ger :.... -

• Staridardfiat fon and* Non-Power * * **

• Reactor Project. D1rectorate .

Division of Reactor Projects.- III, .IV,,'.

• V and *Sped i al *Projects * * ...

• Office . .

• of Nuclear . ..

Re~ctor. Regulation.

Enclosures:

. l,

• Order or Ariiendment No. 10 2*.. Repl~c¢m.£int pages*for Technical Sp~cifications

3. Safety*Evaluation * *

'.4.

• lnformat ion to be supp 1ied by_ WPI q:: *.S.ec.next*page

.:. _** ">* orsrnrsui-1(m: . .* ,.:::dtlc.k~l'.f:r;lJ~>/ * * *

...  :*. ffiurley/JSni

. * :EHylti:>n . .

~ze~*. .: FMiraglia:

TMichae'ls ...

• ~PA/PA WLainbe' 'PTSB

• EJord.an . D~agari * .

• ~earing tawyert OGC JSct~tci~ OGC-Rock~ille.

NRC &:L~~al PDRs .. ' DNa~h; .PTSB

. D.Crutchfi'eld

• LRubenstein

' PPSNP Read; ng ARM/LFMB .

JBarnhart ( 4) , ACRS (10) rn'i ri itz; PTSB . JPartlow

.. IBai:ley .

• Region i

• . *.See Previous .Concurrence PDSNP~ C *. ',. ' ~D~NP* AD:PDSNP*

• OGC,.Rockvi l le*

_EHYJtOl'.l:' * *_J]1i_~h~~b:c;w. *..*...* ~f:IJ lJ~t-_, . .** EChan. *

• 07/20/88 07/20/88' 07/26/88 .... os/i,5'/atf **

• • ...,.,;,_.,,.:. ** ...*... **:. *,. :* ,. ' .. ........ .. ..,:.-~ - ~ ~ *, , .... . *, .,. ' ...,....... ,..- ,... .- *.., ':* :*-.*:.

. ,*,.. -~UNI1' ED STATES OF*-*. AMERICA

,. .. ,. : ~

. NUCL'EAR

.*.--~ REGULATORY COMMISSION'

. -~

In the. Mattl?r of ..

~lORCESitR POLYTECHNIC: INSTITUTE *. l . Doi:ket No. G0_-134 ... * .

f dcility-. Operating.License No.. R-61'.

Worce.sfar, Massachusetts 'Oi609 j *..Amendment No. 10

) .

ORDER'.MODIFVING_lICENSE

.I .

Worcester .

Polyt'echnic Institute .

(licensee o.r WPl) is.the.h~lder of Faci.lity

. Operating License No. R.:.*61 :(Ucense) iss~ed :o*n December 16, *1959 .and subsequently *

.. rerie~ef on December 30; 1982 .by. the U._$. *NuciE!ar Regulatory Commission (Colilmi ssion).. _The* 1j cense. ~rig ina lly. authorized. operation *of the *worcester

• Polytechnic

• Institute irain.ing . .

and . .

Research Reactor

{facility) .

at.a. power .

• level of up to 1 kilowatt ( thermal)_.. I~ 1967 ~ the license wa~ amen~ed to al low operation.

up to. 10* kilowatts .

(-thermal) at which .level *1t n* now limited. .

The.

• fac, 1ity is .a.. trai~ing and research reactor located in .Worcester,. Massa.chusetts, approx-imately 45_ miles-west-~outhwesi of Boston. Massachusetts, and .is located*

in *th~* washburg* Laboratory on th_e east side. of the WPI campus *. The. maning i~dre~sJs Wo.r'c~ster P_olytec_hnic institute,' Nuclear Reactor. Facility, .*.

w6t*~~st:~r-~ Ma~S~ch~$e.ti~. 01so*9*~ _.. : * . . ....., ........ , , . .

!"*'**:**.-.. , ... ' , , .r ,.; ~ ..

. :, .. ~:- :.. ' *'* ;.. :: ...

. *. 2 '. -*.

II

.*.* On *rebr*ary 25, 1986, t~e Commission pro~*lgated a final rul:

• fnlo CFR .

. )0.64 of. ft~: ~egulatfo11s Jimitirig; the ~s~ of high~e~rich~~ ura11iu.!11 (~tu) .fuE!l _*

fa domestic research and 'test rea*ctors- (no~,;;power ~eattOrs) (see* -Si FR 6514).

• The rule, which became effective ori March 27,* 1986, r~quires that ~ licen.see of * .

ari existing non-power reador replace HEU fuel at its faciHt;)' with ltjw-enriched uranium (LEU) fuel accept~ble to the Commission: (1) unless the Commission*:has de.termined that the reactor ha_s il uriiqu:e purpo~e arid (2) c,oriting~nt upon*. .,

Federal Government fundi~g for conversion-related costs. The *rule is intended to: promote th*e* common defense and security by reducing t*he: risk of theft and *

'diversion of HEU fuel used in noh~power reactors clnd the adverse co*nsequences.

.* to public health and safe~y and the environment from such theft or. diversion.

l_Q CFR 50. 64 ( b )( 2) ( i) a*nd ( i1). require: that a* l ken see of a rion-power * -*

• reactor:_* (1) no't initiate acquisition nf additional HEU fuel, ,.if *LEU fuel acceptable to the Corilnissiori for that rea*ctor is ~vail~ble* whe11* it proposes

.- .* t~at acquisition, and (2) repl~ce all HEU fuel in its possession wi_th availabie

• <LEU fuel a:cceptable to the Commission .for that reai:tot", in accordance with a*

• schedule det~rmined pursuant to 10 CFR 50.64(c)(2),

.10 CFR:. 5b_~64(c) (2)ti) of the rule~ . :among* other* things, . requi.res *each.

~r.~:

. . ~

.

• e }~ ~~-r:~e'e_  :~o~~PD~~r ,~e~~t~r, -~O~h~,rjz.~d ~~_P,o,~s-~s s' a,~~ ~to .u~~ :H~µ -~~el to t d~veiop an'd tC> sub,lllit t*o t,he Director of the Office of Nuclear Reactor

,Regu_lation :(frirectoh by March 27; 1987~: and .at *12-morith i_rit~rvals. thereafter,.* .*

• • • • • . ..:;:., .. *.. ,, ..,;,. :. ~,, .. I'*, *~ :-:: , *.,; !:,

• ~ .** *; ....

<10CFR 50~64,(c)(2f{i)alsor;equfres

/ *. **, ... . . the licensee fo. includ~ in.its . ' ..

propos*al:

(U a... cer{ification . .

• tha(Federal

<Gov~rriment funding

.fortonversion is*.available. .

• thrQugh*

the. Depa~tment. .of , Energy (DOE) or. other*

appro'priate Federa 1 age~cy, and *

• • • . (2).~ ~ch~dule for conver:sjo~; based* Upon a.*vail,ability: of 'f!J.el ac,c*e.p.~able:.tO the CQ.ininissfonfor that reactor a.nd upon ,consideration of other factors S!Jch ~s

..

• the availabi'1i,ty ~f sh,f~p:irig ~~sk;, i~plenientation of ar;angements for.the.*

• available financial support, and reactor usage.

10 CFR 5d.64(c)(2)(ifi) requires the licensee to include in\it~ riroposaJ;

. to t'he extent required to .effect conversion~ all necessary changes' to the,

• license, to the hcility, and to th~ licen~ee'sprocedures (all three{ypes of changes hereafter ca.lled modifications). This *paragraph also requires .the licensee fo provide supporting. safety analyses so :as to meet the s~~edule '

• '.*.* established for ~onversion.

lDCFR 50~64{c)(2){tii) also requires.the Director to review.the*

licensee's proposal,.to ¢onfirm the status**ofFederal Government fundihg 1 ar:id to.determine a final schedule, *if the licensee*has submitted a. schedule.for conversion.

19.,CFR 50~6.4(r:J(3). re.qu,;'res ~he .Dire~tor to revi~w the licensee's, ..

• ... . *,. .... ~.. . .... ... .. .. ' ..... '**

_ --: '.: . )** .

' : supp,ort ing safety analyses .and to issue an 'appropriate e.riforc~men~ ,prder ' \

..* ' clirecting both the convers:iop ard} fo -~be, :;x~-~~.t ponsistent with ;protectin~f

' C ~*. ihe *;.~*~.li C ~~~1th,~~~*:~~;~*;; I any necessary modifications.. The Coimnhs ion .

• . ex:p~~jned i.n* the statemenf *of' ~CH1Sideratiorls :of the ffnai. rule ,fh,at,. ~:n* most.*

~f~~t :{:iiM::: !:;;:~{0i!t;J2;:ef;!;fIJ\!,"~I~;;;" f drm)t:~h 9r~er t{.

... , :,.' . ,:..,; ~ *:**.  :..... * .~ .:::: : l "*,::*.::,

. *~* ~ *~.*

.10.CfR 2.204_p,rovides,**.a.mong:.other* thtng'~, that:*t~,e.Co~J_ss.t<>.o: fflJIY ITIQ.dJfY: ..

• *. * * * * **** * * .

• l *

. *a. Hce*nse ~Y: ...

iSS1J1rig

.. an.

amendment. . .

on. notice t'o the.* licens~e-: that 1(~ay.. dem~rid i heari rig wi fh tespec:t to ~n;,: part or a11 of the ame,odm,erit within 20 :days. from:

.. *. th.e date.o*f the notic~ or such long~r. perio*d .,a's .t.he tiotice may* provide. The .

amendment wil~ becQme effe_ctive on the expiration of this 20-day~or-longer period. If the licensee requests a hearing during this period I the ameridmerit

. wn,. become effective on* the date specified in an order made after. the

., hearing.

10 CFR 2,714 sets out the *requirements for a person wh.ose interest-may be*

affected by any proceeding to initi~te. a he_aring orto .participate *as a

• • .party ....

II I Oh September 17 1 1987 1 -the Director received the licens~e*~ proposal,

. includi~g its proposed m~difications, supporting safety anal.yses and schedule*

f~r conversion. The conversion-consists of r~plac-ment 6f h~gh-enriched ~ith low-:_enriched uranium fue-1 elem~nts.

• The fUel elemen'ts contain MTR-type fuel pla*tes with t~e fuel meat in the forri1 of uranium aliJminides disper_sed in an alurni*num mat~ix *. The enri.~hriient is iess than 20% .in the U-235 isotop_e. The- *.* ... ,.;.*

lic~ns.ing Conditions and Technica 1 Specif{cati.on changes needed to amend the .

.,,Jac.ility licensiLcn:e .Jncluded. Jn., _the atta:c;hment_JQ this. Or~eri ..,' Q.n. thft~a$es.:' .,.

• Of the H c~nsee s. subm.ittals I

and . the requfrements. . . .

of 16 ci:-'R 50.64 ,: I have. .

• ..** jnade*_*a* :det~rmin~tjon .'th~t .* th~_- p~bl ic .,hea lt,h, and. safe'ty* a_~d- the common *~eferise

• **.,...

  ;, ** :;-*:~ *...*. , *, .

. - . 5 -*

. :~nd. s,ef.urity .r~.q~irf ~h~ Jic~~se.ft.o :converf fr()ITI the use of ~EU* to LEU; fu.:eJ.. .*

pursuant to. the-modifications.set forth in.the att~chment* in acco~dance wHh

.I the sc:hedu 1e set- *ou't be 1ow.

IV Accordi~gly, ~uisuant to S~ctiori~ ~1, *53, 57, 101, 104,* I61b.,.161i., arid 1610. of the .Atomic Energy Act of 1954, as amended, and to the Co~ission's regulations in to CFR 2.204 arid 50.64, IT IS HEREBY ORDERED THAT:

On the later date of either receipt of low"'.enrichl~d uranium fuel elements*

by the licensee or 30 days following the date of publication* of this Order 1n

. the Federal Register, Facility Operating Licens~ No. R~61 is modified by

_a~eriding the License Conditions ~nd Techn1cal Specifications as ~tated in the

~tt~chment to *this Ord~r *.

V

. Pursuant to the Atomic Energy Act of 1Q54, as. .lmetid~d, the licensee *cir any other person adversely affected by this Order may request a hearing within 30

. days of the date of this. Order. . Any request f ~ir *a. hear in~ shall be submitted

.to :the.Director, Offtce .of. N~cleiir Reactor Regulation, U~S. Nuclear Regulatory.**

,.,..,... ,. t:9.!l'"tss j or.i,, .w~s_h i ~9!9~, _pc ?,055§ .:~i ~h. a.:.~op,Y to_  !.~E! }~s*~ ~~ln~., ~e~erat Counsel .for Enforcement at the* same address, .

J(. . a person othertha.n the

. *. Ji_cens*ee feqyestsa h.ea~'ing, th_at person shall.s~t forth with pifrticularity in

• . :acc'6rdance with.JOiCFR :2.7.14. the ~anner.Jn .'which :Jhe,.p'erspn*'.f. itit~9fs,t . . i$, .

(>if../>{i:.;ad:ver.,s.~--1:t.Jff~ct~d ,by:* ~his:9.rd-~r **.

• r.-/:.. :~: ..'. .* . \):*. ....

t.;:,Xi.3(:'.(J:;\::,::/:\\::\:::,:L*; }-;,;.,_-.*_,:.,:::>*.*-i*-*::*:**.J.-*.*~-: :, :.:_::. :.

If a .hearing is rf;!ques'ted. by the. licensee.or a pe,rs~n whose.,.Jnterest is.

~dverselY, affected_, the Coumi~sion shall issije 'an Order' desig'natin{ th_e time

.and place of :any *h~ating. If~ head.rig is* held, "the issu~ to.be considered at :

such he*arings is whether. this Or~er should be sustained ..

This Order shall become effective on th.e later date of either.the rece_ipt of low~eririched uranium fuel elements by the licensee or 30 days 'following the date of publication of this-Order in the Federal Reg.ister or, 1f a he*aring is.

requested, on the d~te specified in an order fo1lowingfurther proceedings on this Order~

FOR THE NUCLEAR

. ..REGULATORY

. . . COMMISSION*

Jt..~*e,i:f Thomas E. Murley~ Director Office of Nuclear pated at Rockville, Maryland this 12th day of September 1988.

Enc.losure:

• As. stated *

.. ;, ,** :;. m*,w*, ***

ATTACHMENT TO ORDER

• ** MODIFY.ING f ACILI;~ ~PERAII~G LJcENsE Nb~ R~6l A*.* *. **. i. fcells e coiidit; on s R0v fsed And ~dded Bf This Order .

• N6 *. 2.B.(2) .*

• Pursuant to the Act and 10 "CFR Part 70~ "Domestic*

• Licensing :qf Speciaf'Nuclear Material." to receive, possess*

• and use up to a maximum of 5.2 kilograms of contained .

ufaniu~ 235'..at.enrich~ents equal to-o~ les~ than 2Q%.arid 16 *

• grams of ~lOtoni~m as Pu-Be source for use i~ connection ..

with operation of the reactor. . . . . ..

. No. 2.B. (4)

• Pursuant *to th~ ~ct and ld ~iR.Part 70, "Domestic .

~ice~sing tif Speciil .Nuclear-Material," to possess. but.

not ta*use, a maximum of 4004 grams of contai~ed ~ranium at greater than 20% enrichment until the existing.. *

• inventory of high enriched uranium is removed from the facility. * *

. No *. 2

• C* ( 2 ) The Technic~l Specifications contained in Appendix* A; as revised through Amendment 10, are hereby incorporated* in the 1icense. The l ic:ensee sha 11 _operate the reactor in

. accordance with these Technital Specifications.

_B. Technical Specifications Revised By This Order

. 2.0. SAFETY LIMITS AND OPERATING .RESTRICTIONS

2. I *. Safety Limits Shutdown Mar~in: The .minimum shutdown margin under-any con:dition*s with the hig est worth control blade fully withdra~n*shall be nb

• less than a A k/k; * * * *

• Control Blade Withdrawal:* The maximum withd~awal rate for a control blade shall be 7.5 in./min *. The maximum reactivity addition rate

• through movement of the regulating blade shal 1 be 0.006%0. k/k .se,c~ .

Interlocks shall preveht si~ultaneous withdrawal of more _than one

• control blade and sha 11 prevent withdrawa 1 of *any contra l blad~

• unless the regulating blade is.fully inserted. *

• Temeerature and Void Coefficients: The temperat4r~ a~d void0 toef~fcients_3

• of reactivity shall be -more negative than -2 x JO A k/k F. and -*2 x 10 ..

A~/k *i yoid, r.espectively,.~(80e.f and shall npt be positiVe at any. '

averag~ cor~ te~perature aboye 80°Fi . . . . .. .

• .........., .. *. *-.  :.: . * * * .. .:.* *** *~ * ~.. * * * * * :.

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• t .*. ~* ** ;*,, *. .... *:

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• SURVE.I LLANCE ffEQUI REM.ENTS .. :. *

> 3~ 1 Fregue*n.cy :*of~ Sur.ve111 anee:* .*

• . .*sein1anntiall;Y~:: *

• .(°4l. The minimum shutdo~n margin with. the highest worth*.controi blade fully withdrawn s~a11 be verified to be no less. ~han 110. ~/k .. *

(sr rhr: reatt1v1ty worth cif the regulating blade $ha11 .be measured.

Annua 1 iy: At least' *once *each year, al1 fue 1 elerilents sha 11* be, remov~d .

from the core to. the storage racks. .While the fuel f: len:ients are thus

• stored* the co.ntrol blades.. shall be .. brought. to the. surface. and v1sua lly *.

tnspr:cted and the blade.drives lubricated. Blade drop*t1mes *and magtjet r£:lease t1mtis shall be measured. for ~ach control blade, .and a plot of blade drop *times versus distance. shall b.e obtained for each safety blade

• and compared with data of p*revious years. Abnorma1 deviation from *

. pr*evfous .data w111 be .investigated and reviewed by the Rad1.at ion, Health,*

and Safeguards Committee. . . . . . .

• 4.0 SIJE AND DESIGN FEATURES*

4~4 .Reactor Core Fuel Elements: . Standard fuel elements shall be flat p1ate typ~

co*ns1st1ng *of uranium-aluminum alloy clad with aluminum. .The *w1dth arid d~pth of each fuel el~ment .shall bt: 3 in. X. 3 fo~ Each element s*ha 11 have an. ac.t 1ve length of 24 1n. There sha 11 be a maX1!TIUm of

• 10 g pf u-*235 *hi each fu&l*plate and not more than: 170 *g of u.:.235 1n.

any fut:1 e1einent.

• The fuel shall be:.enr1ched to less than 20%. * .*

U-235. Standard fuel elements h*ave 1a*tuel plates, each plate 1.52 mm thick with a clad thickness of .0.381 mm on each side. A maximum of 28stondard. fuel elements niay be insta, led 1n the core. ...

Not more than two experimental fuel elements with sixteen removable fuel plates .s1m1lar to standard fuel plates and f1ti'ed*w1th ..

removable top end boxes may be installed 1n the core~ These * .*. .*

elements m.aY ~e used as part of the core assembly either as complete .

elements. or as partial assemblies, loaded with from* 2 to a total of 18 fuel plates each.

4.5.2*Contro1 Blades

. The.r~ $h:all _be. thr~e ci;,ntrol blades. intersecting the cor~, each

• cons1st~i'lg* of vertlca 1 blades 10. 5 in. Wide X 40.5 fn: long W1th a poison :sect for. composed of'bo~on carbide arid.;-alum.1rium. 0;375 '1n.

thic.k. sandwiched between aluminum*:s1de plates.. * *

~*,.,.. * .J. :.N .......

.*. **rhere,.sh.all .. be one'reguht't;ng blade cons1st1ng of a: ver.tica1* .....

.. *sta1n1ess-::stetl blade 10.65Jn.:'w1dex40.5.1n.1ong x.0.125,fn~

• .*. . t~.ic:L *. ,It $ha 11 have* a: reactivity worth of less... thari O. 7%6 k/k *.

Re~orfs***

ad~-t't'1i>~

0

. :In te> rep9rt"s_ otherw1.se required : under, this l 1c;~nse _and* .

applicable regulations * * -* * * *. -.* * * . *

• ..*...***. (,)*The.licensee shail .1nfo"rm the COriln1ss1on of-any 1°nc1dent*or*.cond1t1ori,

• . relating to th~ opera~ion .of the reactor that prevented or could. ..

have prevented a nuclear system frc,111 performing 1ts safety function

• as ~escribed in. th.e Techti1caJ Spec1ffcat_1o.ris.

• For each such

• occurre*nc:e, .WP I sha 1l p'rornpt ly riot1 fy, by tel.ephone Qr t~ l egraph,

• the-Administrator of the appropdate NRC Regfonal Off1ce. l1sied.1ti .

. Appendix D of 10 CFR 20 and"sha1lsubmit w1th1ri 10 days*a reporf1n*

wr1t1ng te> the Director, 01v1s1pn of Reactor Projects-III/IV/V*&

Specia 1 Projects (DRSr), with a* copy to the Regiona 1 Office.

. ,. '1 . . . .

(2) The licensee _s*hall report to. the P1rector, DRSP, in ~r1tfog w1th1n 30 days, any obst!rved occurrence of substantial v~ria*nce disclosed

_by operat1d~ of*the'.r~actor from perfo~mance $pec1f1cat1ons contained _in the Safety Malys1s Report or the Technical Specifications. *. .

• *(3) The lict!llsee report to the Dire_ctor, DRSP, 1i1 wr.iting within 30 days, any occurr~n~e of s1gn1ficaht changes 1n transient or acc1derit

• analysis ~s described in the SAR.

5.8 Annual Oper~t1n~*Re~orts A report cover_1rig the previous year shall be_ subinitted to the Administrator of the appropriate Regional Office not later than March 3.1 of each year. . .

It shall 1riclude * * * * * * * * * * * *

(1) O~erations Sunvnary: a SUll'ITlary of operat1ng"exper1ence having safety s~gn1f1cance occurring during the report period, including.

(e) a brief suirinary of those changes, tests, and experiments th~t did not require autho.rizat1ori from the Commission pursuant to

.10 CFR 50.59(a}.

..sAF.hvLi~rrs

.- .*. ,.* . .. . . AND

.. . *o.PERATING

'. ..... * .**REsiRrcnoNs

• • . 2.1** *Saf~ty Limits* . **

..*.*~~!t :et~!f~ ;um ~~:~~~~~~~J~ ;~f.*~~~~~Jt :~:i.::~~.~~~gt=nd.~~~t~~ 1,~~ades fuJ1y:1nserted ~cis1t1on *. * * *

• Shutdown Marffin: .

• The m1.~1mum shutdown ~rgin .under any*cond1tlon with the . I**

h1gh~st wort contra 1 blade fully withdrawn s.ha 11. ~e no. 1tiss than 1%6.k/k. . . . *

'Hagriet.Re.1ease: an'd Blade Oro~ Times: The int~rval between ttie occurrence of t

cu~of:f V<:>ltage.Js~ra~., *and ~ separation of each control. blade from i~s magnet shall not .exceed .100 msec. Total time of insertion of the first 24 1il'~

of the *control *blades fol19wing initiation of a scram signal *shall be less th~n .600 111sec, including'. . .

the mc19net release time. * * . *. * **

Maximum Excess Rt:act1v~: ' The maximum excess reactivity above cold, cle1ti1; cr1t1cal:shall be 0.51 k/k. * * * *

• Radiation Alarms: Upon indication of. rad1at1on levels in excess of. 50 mrems/hr (20. rnrems/hr for fuel storage) area monitors ~ha 11 actuate audible evacuation

• alarms 1n th~ reactor room and 1n**the second and third floor areas ab6ve the rijactor pool.* * * * * * * *

.Radiit1on,L~vels~ .The ~ax1mum radiation levels l m abqve the pool surface

~nd at the surface of the concrete. shield, when the beam port and thermal c6lumn are closed~ shall be less than 50 mrems/h~. *

. ControlBladE: Withdrawal:. Thf= maximum withdrawal rate for' a coritro1 blade

' shall be. 7.51n.7m1n.* The maxtrnum rea'ct1v1ty addition rate ~~roug'h movement I*.

of. the regulot'ing blade ~hall be 0~006iAk/k*sec *. Interlocks sha*l_l prevent siniultaneous withdrawal of more th~*none control blade.and:shall prevent withdrawal of any c.ontrol blade unless the regulating blade fs fully: friserted *..

• startu Source .. e uirement: During reiictor startup, a r\eutrori source*,produc-ng at

• east . neutrons sec shall be .located adjace11t to the fuel region~

When readings on the log count rate.meter are*below 50 counts/sec, an interlock shall prevent withdrawal of any control blade. . * * . .

Tempt!rature and. Void Coefficients:. The temper~§ure arid void coefficten§s of *

.*reactivity shall. be more negativ~ th~n -2.x 10 *. 6. k/k.e°F and -2 x 10 *b. k/k.%

vo1d, re,~ective1y,. at 80°F, and shall not be*pos1t1ve at,any av~rage core water I temp~ratufe abov~ 80°F.

.*=.

~ai~;lev~ 1:. :The minimum depth

• .

• core foe l el einf nts 1n the* reactor pdo l sha 11 be lo :ft. . * *** * *. *

• of water. abovethe t:6.p of the .end boX of 'the .

Water*PLir1t*r Correcttve.*acHoii shall be taken promptly if the following 11rh1ts .; .

for the poo

• water are not met:

. (*J): .~H l~s~ th~h ,.g:ahd-gr~~t~r th~H*.6~0

.(~). 'tt(sfstjv_itY. gr.e~ter than 5 x lO ~ ohm~criL *

(3) pool \rioter *act~1v1ty less than .10 ~. uC1/ml *

• suRvEILLANCE RE.QUIREHENTS*

.* * .*.... . *. *..* *. 3~;, . *. Fr.ig*ue'rlcY: of Surve 111 anee *

~::~~in1e~r:;,~~~~*~q~t~;*~~~ ~l~~~o~p~~*~: ~p!~!~:dt~~~;;~gmy ~:~t~~=and .*. *. ..*.

1 t.hari one fu11 d~y. the twQ:.safety c~annels, ~be log-N perfod chinnel~

0 the* ..

• console *ann'unc1ator system sh,11 be checked and ensured to be,operat1ona1 . ..*

.~:;t~~*~~!Jlr~: mM:di~~1~~.:;~t~~,~~ ~~;~~~~.~:~ !~:;~~~llate~ 1eve1 Semiannually:* At *least sem1annua 1ly, a reactor. 1nspe~t1on sha l1 be ;performe~

co~sisting of ** ** . . * * . * *

(1) The excess reactivity cf the core above cold, clean, cr1t1cal shall bE:

measured. *. * . . * * . *. * . * . * *

• (2) The cqnsole 1nstrum,er;itat1on shall be cal1brated by a fo11 activation 1r.east1re~nt. of reactor power where appl1cab le, or cal 1brated by other

• means *. and checked for proper. cond1 tfons ~* ** . . *. * ** *

• . (.3) PooJ water *pH shall be measured*and ~onductivity al'!d pH devices shall be ca l1brated. * . .' . *. * * . * .

(4) .* The minimum shutdo\iin margin with the. highest worth control blade fully withdrawn shall be verified to be no less than 1%A k/k. .

(5) .*The reactivity worth of the regulat1ngbladE: shali be measured~

Ai11iuall : At least once each year; all fuel elements shail be removed from *l e core to.the storage racks *. While the fuel elements are thus stored, the c6ntro1 blades sha11. be brought to the surface arid visually inspected ~nd ,he.

• blade drives Jubr1cated. Blade dr.op times and magn.et release times shall be measured for each control blade,. and a plqt of. blade drop t1~s ver.sus d~stance shall bE> obta1ried.for each safety blade and compared with data of prev.1ous yei,rs *. Abnorma 1 dev1at1on from previous data w1 l1 be investigated and rev1e.wed by t~e Radiation, Health, a*nd Safeguards Committee. . . . .

3,2 Action to be Taken If .maintenance or reca11br*ation .is required for any of the 1teins, 1t shall be performedand'the 1nstruinent sha11 be rechecked before reactor startup proceeds *

. 3~3 Radiation Detection Area Monitors: Area radiation sensors capable of detecting gamma radiation in

. * .*~6e rapge Qf:o.1*to*.100 mrems/hr shall be installed near the*beam port, dem1ner-

. alizer, thermc1l column do9r, fuel storage area, and .less: than l mabove the.: .

. tor~ pocrl; si.trfa.c:.e*~ ~pon:* 1.nd icatton .~f f".i!d1at1 on Jeve1 s 1n: excrss of 50 mrems/hr *

(20 mre111s/hr for*fue1 storagE:) these irion.itors shall actuate audible alarms Hi

• the.reactor room and 1ri .the second and: third floor areas. .ab.eve the reactor pool.

~#ecs*

• 6*

SITFANO<DESIGN

. .. ,.*:, FEATURES

, 4~J She. , . .. .* * * .. *. . . .

. .* : The :r~actor and asspctated equipment is ho~sed .in tM Washburn*Laboratories.

• .*. *.*. *.. located betwf:en '~est' Street and Boynton Siree( on t.he .canipus of Worcester

. . *PolYtechnic. Inst1.tut.e 1n Worcester, Massachusetts.

k2 Restricted Area and Exclusion Area' The reactor room shall constitute a restrict~d area as d~f1ned 1n 10 CFR 20 and shall be cqntrolled by partitions and normally locked doors~ In add1t1on, two*small are~s,*one each on th~ second and*th1rd floors of.Washburn Laboratories, cJ°1rectly above the re'ador control drfve*s ~ shi11 become * ..

restricted areas whenever the radiation. levels 1n any' of the rooms exceed

. those sp~cified *in 10. CFR 20.105~ The exclusion areas~ as defined in *.

. . 10 CFR 100, shall consist of the reactCJr room and the areas above the reactors.

4.3 Rt!actor Building and Vent_11at1on System .

The reactor shall be ho~sed 1n a closed room ~hat *i~ designed to r~strict leakagE:~ The ventilation system shall provide at least two changes of a1r per*

hour* 1n*the reactor toom whenever the reactor is operating;  : ..

.4~4 Reactor Core

• . Fuel Elements: Standard fu£:1 elements shall be.flat plate type consfstfng of uran1um-alum1num alloy clad with a lum1num. .The width and depth of each * *

• fuel elemt:rit shall be. 3 1n. x 3 *1n. Each element shall have an 'active .

length of** 24 1n. Ther*e *sha l1 be. a max1nuim of 10 g of U-235 1n each fuel

• ,plate and not more than 170 :9 of u-23*5 1n any fuel ~lement.- The f1.1el shall be enriched t'o less than 20% U-235 *. Standard fuE-1 elements have 18 fu*e1 plates, each plate 1.52 ITll1 thick* witti a .claq thickness of 0.381 lffl1 on each. s1de. A maximum of 28 standard fuel elements may be inst&lled in

• the core. * * **

Uot more than two exper1metita 1 fue 1 e lf!ments with s 1xteen. removable fue 1 plates s1int hr to standard fuel plates* and fitted with removable top end boxes may be 1nstal.led. in the core. These*elements may be used as part of.the corE: assembly either .as complete elements or as partial assembli~s. loaded wtth from*2 to a total of* 18 fuel plates ea.ch.

4~5 Reactor SafE:ty and Control Systems

. . , .. : The . safe:ty 'syst~m, sha l1 .be*. des 1gnt:d .so .. tha.t, no stng le . E!lectrt!:a,l fa4 lt .. that

• • , partially or co!ll>letely disables the automatic: scram functfon can, 1n ciriy

• ri1aririer~ 1rripafr or ~1sabl~ the manual scram function, atid v1ce versa~ The **

~aftty system.shall be fail safe with r~*spect to loss of voltage;, *

• . ' " ,: Wor~est~r ,: T~c~. Spec; s '. . . ,a Arrienclment No,. 10 , .*

...... ;;**.**,;,,:....... *, .. ,, .,:.::**** . ., .~ ..... ,.*.,*.:

4~5:. 1 *'Nuclear 'I nst~ume,itat fon * *

• .. The cha~nels of nuclear fo~trumentatfoi'l ( listed below w1th th~ir minimum*

,

• c,perat1n9 ranges>* shall dur1"g .a11 reactor cr1Hca1 operatton.*s be operat1ona1

• . and sh.all'be ce>nnected to: t.he safety system,.*except as.not~d 1n Ta~,, .4.1. .

Jl) startup channel; background to 10- 2s full po.wer, 1.e~, background to 1 W

• (2) log-N per1~d ~hannel; 2 x 10- 3% to 150% full power; 1.e., o.*2 Wto 15 *kw*

'(3)

• Hnear safety channels l and 2~ 2 r. 10,)~rto 150 full power; 1.e.~ 0~2 w to 15 kW .

4.5~ 2 Contro 1 Blades .

• .There sha11,be thr-e

.vert1cal blades 10.5 of boron carbide and contre>l blades, intersecting the core, each consisting of 1n. wide x 40~5 in. long with a poison section composed aluminum 0.375 in. thick sandwiched between aluminum side . .

I

• plates. * * *

• 4~5.3 Regulating Bl-d~

There shall be one regulating blade consisting of a vertical sta1nless-,stee1

. blade 10.65 in.' wide x 40.5 1n. long x o. 125 1n. thick. It shall have a reactivity worth Of less than 0,71,L\.k/k. .

4.5.4 ~lade Pos1t1on Ihd1cators The blade po,s1tioil 1nd1cator on the console shal.1 provide an .fod1cat1on of the blad~ po11ti6n*to w1thfn +/-,02 1n, S1gnal lights shall be. ~rov1ded for.each

• control blade dr1ve and for the regulating bladr: to 1nd1c;ate*the upper and lower 11m.its of travel and, 1n the case of control blaaes, an armature engaged by a magnet. *

. :. **,~*' .. *.~ ~ ,.

...9 *.. Amendment No. 10 .*

' : i.*; .. -~ ..,. .' *_:-.

Tt!rnpQ*r-r.y proe~d.ur(!,s* that <fl? ~ot c~~n*ge th.e 1n~~nt of: t.t,e tr1,1t1al ~ppr-o,val- .. , . 1 procedures* ,nay bf .c1uth.or.1zed *by-two ""mbers of* th, fad 1ity staff at. leasl one -

.** ofwhbni' sha 11. be a* lit::en~ed sen fof o.peiator *. Such. pro¢edtires. sha l T' be. subs~- .

. :qu~_ntlt rf;!y1f!wed.

. _by .the. .Rad1at1qri, Health, an~

Safeguards Colllli1 ttee. . .*... .*..*. .* .

s. 6. *operati n9 Records .

In ~dd1t1on t~:records required elsewhere 1n the. license. appHcat1on, the*.

fo 1lowing: records sha 11 be kept of . * * * * .* . . * . * .* * . . * . * *

• • .(1)

• rH(:tOr operation, inciuding power levels and pedods:of operation.at

.each: power. level .* * * ** * * . . * *

.(2). maximum r*ad1oact1v1ty released or disch~rged into the. air 0~ water beyond

• .* the *effect he cont.ro1 of the licensee as measured at. or before the point

• of such reJease .

cir discharge: .. *

. (3) emergency shutdowns and 1na~vertent scrams, 1ncludi.ng reasons* for emer.:.

.geric.y shutdowns . . . . .. ..

• (4) maintenance operaticm.s 1nvo1v1ng substitution or replacement of *reactor equipment or components (5) experiments 1nstal led including description, react1v1ty worths, locations, exposure *t1nie, total 1rrad1atfon and any ui'iusual events involved 1n their performance and in their ha~dling *

• * (6) . tests and measurt:ments performed pursuant .to the Technical Spedf1cat1ons (7) i~cor* 1rrad1at1ons

.. ~. 7 Reports .

In addition io reports otherwise required under th1s license and ,applicable regu1ations (1) The 11censee .shalt 1riform.the Commission of any 1ncider,t or condit.1on rel.ating to the operat1on of the r.eactor that prevented or could have pre-vented a nuclear system from perforriii.ng 1ts *safety function* as desc'ribed

• 1n the Technical Spec1f1cat1ons. For each. such occurrenc~, WPI shall * .

promptly notify, by telephone cir telegra~h, .the,Adm1n1strator or the appro- .

. priate NRC Regional Office listed 1n Appendix D of 10 CFR 20 *and sha 11 .

• submit w1th1~ 10 days a re~ort iri wr1t1n~ to-the D1rector, Division of Reactor Projects'."III/IV/V & Special Projects (DRSP), with a copy to the

• **Regional Oft1ce. . . . . . . . . .* .. *. .. . . .. . . -

. (2). Th~ licerisee .sha1*1 r~port t'o the ofrector*, DRSP~* 1ri writing w1t'h)n 3'0 days, any ob.served o_ccurrence of .su~stant1~T.var1ance *disclosed by**

• oper~tlon**of*'the "reactcir* from :p~rfqrmance sp:et 1f1cat'1ons *contained *1n the** : -* * * *-.

• Saf~tf Ana1ys1s R~port or the Tethn1t~l .Spec1f1tat1oris. . *. . * * ..

.: {3 f. The 1icen$ee* report t()*the:Director,* DRSP, fn. writing -~1fh:1ri_' :fo, days,-*.*ariy **.*

• ~ccurrebce:of s1g~if1cant changes in,trans1~nt or.~cc1dent ana1ys1s-,as * *

. :. .:de$.c.r,1~~-d. Jn.' _t.he .S.AR.: *-* : ,i:..:, . . * * * ....:.... :. ,. . * .... , . .-*. :....

• ~j3; Ann~al Operating R~ports . *. ***.* *

. .. A r~porf covering the prevfous year sh.al 1 be . subm1.tted .to 'the Adm1n1strator of .*..

• , the: ~pprQpr1a.te ~t!g1ona 1 'Office. tiot Jater tha.n Marc::h 3.1 o.f each y,ar. It *

., $hall *1nch1de . **. * . * . . * . * * * . . ... * ** *** * ** * * * ** * * * ** .

(1) O~erat1ons Summary: .. a sutrmary of *operat1n9 exper.fence having safety s1g-: .

n f1c~nce occurr1ng*during the reporting. period, including *. . .

(a) .. changes 1n factlity<des1gri (b) performance character1$t1cs (e.g., equipment and fuel performance)

(c) changes ,in operating procedures th~t relat~ to the safety of facil;ty ope~at1ons . . . . . . ..

(d) ariy abnormal ~esults.of surve1llanc~ tests and 1ns~~ct1ons required

• by these Technical Specifications (e) *a brief summary of those changes, tests, and experiments that did not require author1zat1on frcim the Corim1ss.1on pursuant to *10.CFR. 50.59{a)

(f) changes in the plant operating staff serving* 1n. the pos1t1ons of . *. *

• Reactor Fac111ty Director, Health Phys1c1st, or Radiation, Ht:alth, and

. Safety Conrn1ttee members * * * * * *

(2) Power Gener~tion: the most current su111TJary of thermal output of* the factl~ *.

• 1ty available together w1th a su111T1ary of the total thermal power generated over the lif~ of the reactor *

(3) Shutdow~s: ~ 11sting ot unstheduled shutdo~ns which have.occufred during ..

the reporting period, t~bulat~d according.to cause, ahd a brief discus-*

s19n of. the actions takeri to ~revent recurrence * *

(4) * ~1aintenance: a d1scuss1o~ of. corrective maintenance (exclud,ing preventa-

• the maintenance) performed *during the reporting period on safety related systems .and components (5) C~a ges 1 Tests and Ex~eriments: a brief descr1pt1on and a su111T1ary of .*

afety evaiuat1on for those changes, tests, and exper1mt:nts that were carried out without prior Co111111ss1on approval~ pursuant to the requirements of 10 Cf"R 50;59(a) .. .*

(6) Radioactive.Effluents Releases: . .a statement of the quantities of*radio-actiVe effluents released from the plant 5.9 Fuel Storage

. .J.w~ fuel storage racks.are located on*oppQSite sides of the. r.eactor pool *... Ea.ch .

• ,rack shall be designed to*contain not more*than*l8 fuel.elements *. When the * *

• • • ~:reactor, contair1s a critical ruass,. all add1tional.fuel.e1ementsnot. Jn.the'.core ..

, s~all bt. lo~ke'd 1n place except as authorized by the licensed senior operator .

.... iri.. chafge..

... A fuel*e1em£:nt sh~ll not be stored outside of the reactor pool unless. 1t produce$ .

.radhtion dose levels of less than 100 mr.ems/hr at the *storage corita1ner surface *.. , .

• j Storage conta*1ners of fuel elements sfral1 be 1ock.ed c::losr::d when &.4natte'nded~ .* .* * *

. *.* .ir*.* **: ...~:** .-~- . ,., *:' .

', .. : ' '. ;~ .. _:_ ..~*,. :'

, .. ,.*.. UNITED STATES ., .. .

• ~).******.* .NUCLEAR REQU.LATORY COMM1$SION WA~INCITON, o. C; 2,(>155 .

.. :"~**!'.~o *. .

SAFETY EVALUATION ev THE orf1 CE OF NUCLEAR REACTOR* REGULAfr ON.

• SUPPORTING *CONVERSION ORDER TO CONVERT FROM HIGH ENRICHED . .

T(f LOW ENRICHED URANiUM.. . . .

FU.EL

• FACILITY OPERATING uc:EN.SE *No. R-61

• WORCESTER* POLYTECHNIC .INSTITUTE

• DOCKET NO. 50-134 l~O INTRODUCTION.

In accordance with. 10 *CFR 50.64, which reqidres that non-power reactors convert to a low~en1ched uran1um (LEU) fuel, excep_t under c~rta1n conditions. the Worcester Polytechnic Institute (WPI) has proposed to

. convert the. fuel 1n 1ts pool"'.type tra1n1rig and. research reactor (the reactor) from. h19h-en*r1ched uranium (HEU) to LEU * .WPI submitted a .Safety .

Analysis Report (SAR) and revised Technical Sp_ec1f1cat1ons *(TS) dealing with the changes needed to convert to LEU fuel on September 17, 1987. *rhe*

staff "s safety r~v1e~ with respect to ,ssu1ng an order for conversion from HEU to LEU f4e 1 has been based on an aria lys 1s of WPI 's SAR and the ,*

• proposed TS as we11 *as 1.nformat1on provided by* WPI on February ,10,* 1988 in response to staff questions *. This material 1s available for review.at the Cormi1ss1on' s Public .Document Room at 1717 H Street, N,W., Washington, D.C.

• This Safety Eva1uation. (SE) was prepared by T. s. Michaels, Project

• Manager, D1v1sion of Reactor Projects III, IV, V, *and Speciar*Projects, *

• Office of Nuclear Reactor Regulation, U.S. Nuclear .Regulat:ory Comm1s~ion *.

Major contributors to the techn1ca l rev1e~ include R. E*.carter, W. R.

Carpenter, and c. H. Cooper of EG&G, Idaho National Engineering Laboratory (INEL). . .. * . . * ..

In addition to the changes assodated with the HEU to LEU *conversion some minor TS changes, which do not perta1nto the convers1ori, were made to

• tipdate and clarify the intent of th~.TS.

• ;i.O EVALUATION

. General

. :. ,*.*' The.*. ,WPI. reactor curr:ei,t.lyJs_' 11C~nsed for opt!r~tton ., -~.-~ .. P.o~er ,l~y,J~* not:* . *

.

• to exceed lQ kW therrnaJ, using MTR-:type fla~-plate *fuel, and _cooled by

• .* .. natural thermal. convection of the pool water. The license';!. has proposed *

• no changes lo:any reactor systems or *operating *character1~t1cs excep1; for

• the rep*1 ace~nt >of the HEU. fut!le 1e~nts by' new LEU. ft,,e 1 e l~rile~ts. The

fo1low1.ng :eva luatfons and coriclus1.ons are. base.d on that assurnpi1on.

. '... \~-.-*  :, .

• Fue 1 Construction and Geometry

• The HEU.fuel elements currently 1nsta11ed at WPI contain 10.plates each, 1n whfofr*the fuel meat 1s a. 93.4% enriched uranium aluminum alloy, . Each fue1ed.p1ate>conta1.ns approximately 13.6 grams of u.;.2~s for a total u~235

' loadfog of :about 136,grams per fuel elefflt!nt *. ' The new LEU* fuel elements*.*

.* w111 have the same outer dimensions as the HEU fuel .elements, but w111

• .. co.ntain .18 pl~tes f!ach, with the fuel meat 1n the form of uratifum

• a1uin1ri1de (enriched to less than 20%) dispersed. 1n ari. al'liinfouni' matrix.

The LEU fuel~d plates will each contain approxi~~te1y 9~3 grams of*U-235 for atotal*U-235 loading*of.about 167 grams of U-235per fuel elemerit~

The standardited LEU plates are thinner th~n the HE~ pl~tes, ~1th thinner aluminum cladding, so, even though there: are more LEU plates per fuel *..

• t!lement, the lllt:!tal-to-water rat1o for the LEU and HEU fuel elements ts very nearly equa 1, with the LEU fuel. element being sl 1ght iy higher, 1.e.,

• slightly lf!ss. water volum~ in the new LEU fuel elements. Fuel elements ,*

.with plates and.uran1u~ com~os1t1on essentially 1d~nt1cal w1th the.:

proposed WPJ plates wen: reviewed .. by N,~)and lfcensed 1n 198.1 for use 1n the 2MW University of M1ch1gan reactor *

• These fuel elements have

• operated successfully at this higher power level w1th no unpredicted ev*nts havin~ a safety significance. . * . * .

The licensee aho proposes.to acqu1rt: and.use a fuel e1ementw1th removable fueled plates *.* The use of this elemt!nt 1n positions at corners of the,

.* core, B-:3 or F-3, have been considered and such use 1s deemed acceptable.

Cr1t 1cal Op~rrst ing Masses of U-23§.

The cr1ticalrnass of the WPI HEU reactor 1s apprdximately 3~3 kg u.:..235, The. critical mass of the LEU reactor 1s predicted to bf! approximately 4.0

~g V":'235~ This inc.rease 1s due to the large 1nc*rease 1n concentration of u.-238. which absorbs low ~nergy (therma.1) and ep1thermal (resonance)

• energy rieutrons, and causes a hardening of the thermal neutron spectrum.

The 1ncrease of uranium ts achieved bytncreas11ig 1ts concentration in

~he fuel matrix and increasing .the number of fuel plates' 1n the fuel elements. The proposed conc~ntration 1s similar to that successfully achi~~ed and tested.in the* licensed University of Mich1~an reactor.

• In an Argonne National Laborator.y (ANL) r,port( 2 ) the sens1t1vity calculations

. of .reac.t.1v1ty for ,d1fferent*.cor~* ~orif1gurations h d1s~uss~d. , In. t~1s

• study, fue 1 elements Wtfre shifted ~nd/or, removed to form ,:various .core conf1fturat1on's inthe WPI ,HEU and lEU c~res. These fuel elem-=rit * .

. perturbations were .1derit 1ca l between the* two cores and ~he resultant ..

• ***

• reactiv1 ty* changes . were c9mpare~. ,: In, alVcases the reactivity effects. of, . *.'

car~ rtiarrangements between the HE.U ~nd LEU cores 1s v1rtual1y .1dent 1ca1 *. *..

except *tor the r~moval of the center fuel ~,ement where the reactivity : .

effect 1n the HEU core 1s slightly higher. The .re,sults of thts ~tudy,.* . *

• ~gain, demonstrate the n~utron1c sim11ar1tY .between the HEU and LEU cores at WPI, . . .. * . .

i

.. _,. 3 *-:

. Hydraulics and Thermal-hydraulics AtWPI,* there*are rn plates .in.each new LEU fuel elem~nt.as compared.to*

10 plates 1n.eachHEU fuel eleme*nt. Th~ LEU plates~*however, are:th1tiner and conta.in less U-235 (per plate:). This tesu1t$' in less heat gener.atfon

• per plate, du~ to-the thiriner:clad. Als~~*th~*1ncreased number of LEU

.fuel plates per element .is offset by the plates being thinner, which results 1n a very similar metal to water ratio for. the two fuels with the

'.cross section for coolant flow being .slightly smallt!r* 1n each LEU fuel

. eleme.nt. Accord1rig1y, the ANL ca1culat1ons 1nd1cate that ma~1mum fuel p.1atf:! temperatures will not be s1gn1f1cantly different between the HEU and LEU cores (the.LEU plates be1rig coole~). and at the 10 kW power level

. these temperatures are well below the temperature for onset of nucleate boiling or fuel degradation. * *.

• Power Density and Power Peaking

• Power densities .and power density peaking,* including both nuclear and engineering factors, werE: computed by ANL. The powE:r d1'str1but1on among the fuel .elements is essentially the same for. the HEU and LEU cores.

• The

• power densities 1n individual fuel plates arid maxfmum peaking (hot channel) factors were also very similar, but slig~tly.higher 1n thtfLE.U

• fuel. Howevr:r, the over-power at which onset of nucleate bo11ing would occ~r 1n*the hottest channel was almost twice ~s high in.the LEU core as in the existing HEU core, primarily because of the loltler 1nitia1 heat' gen~ratfon per plate.

• Thus the safety margin between the licensed power

. and the power at which temperatures might *lead to fuel damage is mlJch high~r*in the LEU cbre than the c~rrently licensed HEU core.

Control .Red Worths

• rhe reactivity worths of the control and regulating blades were computed by acceptable methods for both the LEU and HEU cores. The values for the LEU core were somewhat. smaller, as expected, b.ecause pf the increased neutron absorpt1o~*in t~e U-238~ but the LEU rod-worths are fully

• acceptable for safe reactor operation and control.

Shutdown Margin

• The C.r1terfon used .for ~hutdown:.marg1n 1,s .that r,.a$o.nabl~ as~4ran~t. b~.

• provided that a nonpciwer reactor can be shut down from ariy operating .

c'ondiflon everiif thri control/safety rod *of maximum worth 1s

• in 1ts. most

. reactive .position (fully withdrawn). On th~ basis of .the c,omputed . * .

• 1 <;ontrol rod-worths and theiauthorized e~cess react-1v1ty~ the:WP.I reactor , .. - ..... .

would be subcr1tical by approxiinately 6%A k/k with the rod of max11T1um

.worth .fully withdrawn *. This 1s substantially larger that1 the Techri1cal

• Specification margin of atJeast 1%6 k/k, and .ts accept~b1e. * .*

Excess *:Reaciivity Additional react 1v1ty above ,cold, clean critica 1 1s re.quired to allow a reactor to perfonn prograiml&t 1c and academ1 c furict 1ons. * *The 11 cerisee' s .

subm1tta1 discussed *and presented calculated changes 1n reactivity caused .

.*by various LEU core conftgurat1ons. There 1s reasonable ,ssurance that * .

~he excess reactivity* permitted by* the Techn1ca l Specif 1cat1ons, wh.ich

• 1s the same for the LEU and HEU cores

• can be ar'" ~;\~ved. .Because the .* '

• authorized* maximum excess ts o.sii k/k*, tnat1'.\fdrtent *1n*serHon'cff ail of this exc.ess w111 notillow the reactor to become prompt' critical so an.Y possible transient power 1ncreasf?would be quicklyterm1nattd by a power level scram or operator intervt!nt1on and would increase fuel tempE!ratures only a few degr~es C, which 1s*acceptable for both the HEU and the

• proposed LEU cores. * * * * **

Reactivity Feed-back Coefficients The temperatu.re coefficient of reactivity and the void coefficient of reactivity were COl!lputed for both the HEU and LEU cores.* Both coeff1c1tnts are more negative than required by the Technical . .

Spr:cifications. The* void coeffictent of the .LEU core is sigoif1cant1y more neg at 1ve .ihan for the HEU cor~ because of the rnor*e under~,noderated LEU core corid1t1on~ The temperature coeff1~ient of the LEU core 1s also more negative than in the HEU core because qf the ep1therrna1 Doppler::

• effect in the neutron capture resonances of the relatively rm.,ch more abundant u-~38 present in the LEU fuel. 'The Doppler fee~bick is prompt, .

and therefore more effective 1ncountering a reactor transient 1n the .LEU

• core than 1s the heat transfer depe.ndent moderator temperature * . . .*

coeff1c1ent.1n .the HEU core. Thus, the~e reactivity coeff1c1ents for the

• . LEU core are larger and more effect1Ve 1n leading to reactor stabi 11tY *.

than the react1vity coefficients for the HEU core, and*therefor£ are acceptable. * **

Fission Product Inventory and Containment The total inventory of f1ss1on products w111 not be s1gnificantiy ...

different b'etwet:n .the* HEU and LEU cores.

• Furthermore, be.cause there are*

18 plates 1n LEU versus 10 1n HEU fuel elements, the inventory per plate.

• . 1s less 1n the ~EU core.* The a1um1num.cladd1ng how~ver is thinner on the LEU ,.plates ,Wh.1ch m8Y .tcmd *to r~duc:e thl! 1nt~gtitY . .Qf :.tht-. f:.1ss1.9n Pr<>.duct barrier. Th1s cladd1ng.~h1ckness, however,1s currently 1n use on the

• • • • Uniyers1ty of Michigan l~U fuel, and has been used on* HEU fuel for many

• years 1n most. of the licensed research re~ctors. Because there have been

• no, faflures or s1gnif:1cant, releases* of *ftss.1on* pr.od~c~s,* attr1butjble to.:

ihts c:ladd1rig th1ckn~ss',. there .:is reasonable ~ssurance that. the new LEU

• • fuel.w111 p~rform s*t1sfai:t'orfly 1n 'containing fission products 1n the

• relattvely b*e.nign environment 1n .thti 10 kW WPI reactor *

. . ~

. - 5 *... _*

• Potent1a 1 Accident* Scenarios * *.

. Amorig the varfou_s potential accidents considered by tt!)L1c~m_see .or the **

staff at the *time .of the 1982 license renewal for WPJ. , only two -could be affected by the conversion froin HEU to LEU fuel. These two .scenarios are addressed below. . . . . .. . .

(1) tnadvettent Insertion of Excess Reactivity.

The ANL <2> report j)resefi, the results of computations* using the modified PARET code

• for stepwise 1nsert1on of reacttv1ty 1n both the current HEU core and the propos~~ L~U cor~~ It ~js assumed that only inherent. reactivity feedback mechanisms 11m1t the transient, and the assumed values are given.

• The **

computation determined the minimum step 1nsert1o~ that.would just raise the temperature to the me.lting point *of the-c_ladding for each core. For _the HEU core the computed insertion was l.5%b..k/k. For the LEU tore the 1nsert1ori"as 2.01ti k/k.

The difference 1s due pr1nc1pally to .the prompt.Doppler coefficient and the larger average vci1d coeff1c1erit of reac_tiv1ty 1n the LEU core as discussed previously.

Betal.ise the WPI Tech~1cal Sp~cif1c~tio~s 11m1t the -excess reactivity.to 0.5%~ k/k, _a step 1.nsert1on:of this Jmount was also analyzed. The computed maximum fuel t~mperattires were slightly' above 100°c for both cores, well.below temperatures at wh1ch fuel or cladding damage would occur. Also, the

• calculated maximum fuel temperaiure 1n the LEU core ~as slightly lower. than 1n the HEU core~wh1ch 1s acceptablil.

(2) Fuel Handling Accident.

An accident 1~ad1ng to structural dam~ge ~ri air.bf_~ fuliy irradiated fuel element was considered to .be the. ma>.<.1mum . .

hYPothet ica 1 accident by both the licensee. and the. staff 1n the evaluation of the WPI reactor facility for renewal of its operating license in 1982. Th1s same accident was also .

• cons 1dl!red by the MIL group 1n. 1ts assess!Tl(;nt of the LEU fue 1 .*

at WPI. The only significant difference between the inventory

. of radioactiv.HY fo the LEU and ..tn<the HEU.:.e.le.ment 1.s,_ih~ . *.

plutcrnfum-239 formed by neutron capture in the ur~n1wn-238~

wh kh 1s im.ic:h mo.re abundant 1n the LEU Jue 1~- Heiwev~r~ on* ~h~

• basis of the licensed power level and consequ~nt btirn.:up o.f .

• *

• fuel at**WPI-, *the add1t1qnal buHd-t.ip of pluton1um*tn the'*LEU

• J~e 1 1s. radfo logic a1lY tns 1gn.1f1¢an..t,

• and re lease of Jhe.fis_~ fon

. products 1ntlud1rig th1f pluton1uril froni daniage.d lE.,tJ fuel would *

• *. res_uJt tn max*1mum poteritia 1 rad1at fon expos4reJ *in the. un;;. * . * ..**

r,str1cted ar,eas of <>nly l sma11 *tr.~ctioii c,ff: ihOs~! alJo~ed by *10 ...

GFR io g1Jtd~l 1nes. Therefore~; ~am~g~ to LEU f~~F1ri Jilac.*e :of *

~~U.fuer:w.oulcfca'i:i'se*ncf's1gn1f1cijr1t c_ha@tr*ln :tttf rtstt.~ thft * * ** **-* >;, ** .. , ...

• . :h,alt.h ,and s~f~t,y of :t,h~J>U.~itc,: wh.1ch .was: i.lready acc,:pt*Pl,Y..

low for :th.~: eur.r~nt HEU cqre .. *:. *. *

. J.O,.E~Y.UO<<MEfttAL.,CO~S.I

• . :i . . <<:::~'-R'.('f;**_.*

,:*.***.:.* , .... i;<<, .*.* i ,. ,. ', *'**-*:

.. ~ .. I,ON .

• f.~Jf ~:~~~tnf#rt

¢!!)ilipp~~~t$. J9_tal~d wftb.1:n*

t~yoW~~ icnMg!s* 1::n_ th* _*in$.,~llc1~.ion: 9" ::~*si!:*~f t~~*-j11tr.* *: ..

to~ .r~ttr;i.~t,d*: ~r~cr .aJ d~J.t~ef tn. 19 .Cf.'.R P~t:t .

.-.l:$';:t-~~:~1.1~* it*.:*~i~;f.::~~d;::tt~~:tJJ;n~;-_ --t1~Mt1t:~:J.1.nci:tstt.1~ffn~---

. -~.mo4.M.s,. Joa: ~9 ._ Hsn.1f:Jt.a:nt fMii:9.~. 11.1- t.nt.-tYP.~$ ,: 9f -~-fit ~fU~l~:r.it~ lM~. rn~Y

. bt-

.. _ .***teleased ............ *offs:.tn ,_ ... and,_... there Js. . no* . ~g *1 hificant. . t as*e

. _.: . .tncr 1h 1n:dfvidu,

.......... ... al * *

• t>:r cumula:t.1v.* occt1patfona1 *:radfaHon :e.xpq;i,,re. AG;coHHi:igl}'; *t.h1$ . * * *

• Jniend,i,ent.'-_~e,t~ Jh~ ,*JWt~1-11tf.,_crlt~r-1~ I.qt c~teg~r.t~*aJ .exclu!de>n. set -**.,

.

• for.th ii::r JO CFR 5l,Z2{cr(9). PiJt'SLt~rit to 10 CF'R, 51.22{bh tip .. : . . .

• Ei:rj.v:i+on.ih~ntaJ impa~t -~d~teriient 6r etivirdnrnen~a 1 *asses.srnent need be .. * .-

. *. pr~par~:a .in .connect-tqn with* (fie tssoante-of this -~trtendti1ent. *.. * *. *

• 4~0 -*cQNCLVS.:tQ~

• **ttie ~;hfl *ha$. conc1uct~d, *based <on the ~on~1deration*s. d*iscutse:d. above; .*

.. lcrea,tf ~ i.~e(**theJ.~.d~:po:01an1ty 1

~-,~ it/.~*,. :::~t:;::~::i* ~;f."::*c i.:~ii;t;~~11::!.~Jc:~*l1-J~tta?.*$ir of f n$~H~t di.ff~rent.J1M oJ 1c¢Jg~r:1t f-rpm Jtiy

-~

J

~¢.~fifEiti.t p,r.evfously evalµate:4{.a.nd qpes :~~t--tnV,9Jve. i) ""tdgnif}<;ant*** *, .

rti1fU¢tton: in a .m~rg1n -~-f $;4.fet:Y1 th~* ~m,ttdm'-fit* cf<ie$ n~~ *t,rv.o lv~. ~

.s:tgniflca~t. h~z~.~d:$ e-on~JderitH>n*, (2). Uttfij. 1l ,tea$on.able JU~tance

. *t~*~:t *tQ~rh~~Jth and s~fet,Y qf .t&.e.:P.~lfl1~ -~ill,n,ot-~¢.jt,t~_~ii9jr~:cf.lt ~he .

• . pro.pbsfd. -a,E:t iflH~J, ~nd (al .$~(;b a:¢Hv,ue~. \t/;Hl be .conijtJ'c-t:ed 1~- . *

• • cgmpli~,n~e w:ltb ttt~*-cqro/!11J~tori'l"re.g:Q*l~ti{lnf*4ti.d _ the* lis.µ~*~¢*~:-tjf tht,s. **

• tit~h9m~nt w*Hl n4:;lt, b, 1i1trri1¢.:a*1 tP .,he, t*qmnto.n tJ*afe.i1$E! anf s'ecurity* br ._.

lliie _healt;h and. ~&Je_ty 0.f the; publi'c.. *.* * *. . .. . . . . . . .. * . .

• , **!Lo* REUR(.NCE*S

f. Am~nQ~nt no. 21 to .the. UoNtit,Hty bf Michigan Ftjrd Nuc le--r R*$a(:tpr Lice_h.$1!; :date.d. "Feb,tuar~ iQ; J981.' .. : . .* ..* * * . *.. .. * .

2:.

• An.~lysls Jor. Q~nv~r.S"i.9.n ,of ~h~ WQ.r¢.est~r P:oJyt~~hr.ric. Jn~thij~e ..*..

@.e.ad or frdJn_. HEV t<> ttu f µel~ Argonne. N~_tton(l ~~!?.oratory~ RJR iR : *

. 1'ro~tam, J. E*; Matos anf K. E. *Fri:d~h Au.gu~t 198*7~ * . '. * *. *- . .

1. . A~,nd~nt-jo~ 7.tp.th, W~r:c~~t.~r PQ.l,Yte¢h.ry~~-- ~fls,tJtu~e u~~*r.-.*P.~01 *... ;

. Tr~_.f;ttrig l9$2-.. . . .

R~*actor :an.d* NVREG.;~~12, S~fM,Y (va.lt.1*atto.n RepQr~. D_ec~mb'er 4

• l;;:

. * * **

• r~.6*.. 20.a

• CFebruar X..,,.

1

_tt:f)_;a_J;~_*:::_ 4

.. ,....**.... ,,,,.. " ,...*..,.,,,.**c**:'"":**,., ... ,*,<,~,~-- *****""'*" ,. *.*.-',.*,

!1):~_'.M:f: l:M:1,

• • . ltMJ

,. ,.,.*.,,c,.,...~-

1 1~:1::f itt!!\~1tt;!t.v

• Eo5W~v.rft*** ..

.- l~FO~MAllPN. TO BE* SUPPLIED BY .WPJ *.

• -* *1 *. ** *. in qt*cter tq provide a tonip9rBon,between meast1red v~lu~s ~Jt~**co.fuptAt~d-.

• pr.edi~tion~ .ple~~f prov+de a r~~ort_sixmohths tP11owfr1g .fuel .loading

• that ' ac1dre$Ses .. :

the Jtetns. ;n

. .. th~

. outlihe of the

. . . atbchm~frit

.. . . . . . to this enclosu.re. .

2.. Pleas~ subnii t a .Fuel ~o~d ahd **Re~ctor Start;up P.lannlng 4ocu.men.t,* With

• • .sp~cHic 'pro.eedures and iriStt'l.1.rrienUtioii req'Uirements. This:*doctinieht ihtju la Ali9..;*~eritify . lhe :per$ohrie 1_*who. _wi 1r.::b.~ .;,wo1:Ved wiJh *. t'~f-star:hip *.

• and ~ho n~ve previoi,is .~xp~riehce with initial ft.iel-.loadtng,. power. * .. * .

. c.ai ihra~ ion* an~* start-up i;,J, a non-power. r~actpr. P1ease :inform .ine of ttte .

8:~Pected 9at:e* when* fue.l lo~ding will* begin and any changes "th~t- may octur lo this date. * * * *

• J, lri response fo, qUEJtion 3 of C>i.lf _JcinUa.ry 2J\ i~~f letter tpyoq. . .

r~cuJestirig 4ctditit>ria.l infof:'ma.tle>n, YQU :$u~m.itte.d twQ.flgutes,. labeled .

Ffg~re 9 and _figµre ~o !(tatir1g. tt\at' *tney ire from *thE!. curre,nt_ SM.** *We*

• note that -HJ th.e,s~ ffgures po not, in ~hems~Jves ~ resp~nd to the *.

• qµ~stion; a,nd.* (2) t,hese .figures ~re differ~n:t from Figures a:, 9 a.iJg. 10 jnclu~~~ .in your. tran.smitt~ 1 o.f September 17, :i 987.~ Plec1se identify w:hJc~ .figlifes .a,r~ to be con$id.er.~d ~s official parts of the SA(Lanij ..

. . e"~pHdn t.~-~lr :relev~~te fo t~:~ Te~~hic;al Spetificatiqns requ.ireni¢1'lts .on

• v<fid ~oefftt.ierit and .te1T1peratore c:oeffkient of reactivity.. *

• i; Pl~ase SubrnH the 'follo~fog corr~ttiQri .~o the tlt>te of Sectfon 2.3., of

• your F¢br.ijary JO, H188. respons~~ to cl rJfy .the ;recC)rd a~ .follows:

(a)* Nvdlear Charactedstit:s.,;-(Calc): Ca} fpr th~ flux eotfies.1mder 1EUi

• the symb.oJ 11 nv 1' appe~r.s *to have nc;i µ$e ~nd.

_the flux .entrfe~ 1Jridef H~U. it is t-ecomm~n~ef th~t the 'liOits qfn/tm 2

-$'h9uJd b~ *Qe:l,~{e~;' {b) f6_r sec be substituted fCJr .the symbol li'rjyi*.. .

{b): . contrqJ, SafetyJlements' Reactivity Cirntr'Ql:. it i$ retprry~enqed

. that th,e lJn.lt of co~trot ~e made more .¢omplete l>y ma ~ing "it rMd

• 11 3.* 5~ A k/k each, m;rttm1J.m 11

• .* ,. '._.., . ~-. :**-*: .. ~

.* : . OUTLINE OF R~ACTOR* START~LW .. .: ' ...

• . R~Poirt .AND* GOMPA~iS~N,~ Jl.lTH -CALc'uu~uoNt.

• . 1.* Cr.it1cal M~ss~ *

~ea*s~renient. ~.1th ijE~ *

• Measurement.*.~iith:LEU . * * * * ** **.

Comparisons with. ca1cuiat16~$ for. ~oth LEU and. HEU.

i~. *txcess (o.per~H~na1). readiv1~y

. Measurement .with HEU

• Measurement with !:.EU Coinpar~ison. with caJc:uiations. . for .

both . LEU arid . *Ht. U.

• *3.

• Control anq regu1 at fog rod ca 1i brat ions *

... Me~s.uteiiJen~s Qf djffer~n,t1~l a~( tOt!!J rod \\'Orths; and comparisons

~1th. ca lc;ul~tions for: b.oth HEU and LEU.*. * . *

4. RQactor pc,~(er *ca 11.bt~tion .

~1~t~ods:. a~d n1~a"s4relllent~. thaf as.~ure 'op~rat*16~ within th~ lic~r.i$,e 1iiTiit .*

c:ompa*rhon *between. HEU ~rid LEU .nliclea.r .1nstrumerita.t1on* setpoint~.

,detector posit-ions~ and detector oµtput. * * ** *

• s. .

Shutdowti .

mar~fn .

Mec:isuremerit witt,* HEU

. Measurement "'Hh LEV . . . * * *

• Comparisons *between th'ese, a*nd with .coinputat'ions fot both.

~-

• P~rt.1al ftJ~.l element worths fo~ LtU.

• . *..*.. Me~s~r~d for ~~ffet~rit .. numbers of plate.s for which th~ fuel 1s capable;

. coiilpar1son ~1th calculation$. . ** . *. *. *.*

7; . *.*fherma*r neutrot1 flux di stributfons, Mea~utenients *wlth HEU ancf.LEU; arid <iomparisonswith each other ~nd calcu1ai1on~ .. : .

.* 8~ ,,' :oisiuss '(jf ton' .h,E?W c_ompii~nf~ ~hh: v*p1~' and. t~ip~r~f uf.e: d,ijfr.i~l~nt .v~ 1Ue.s . . . ..

• hi Tt.!thrdcal SJi~c1fk~lto*n:r :1$ *to :b~ il.Ssur.ed. oompst1$ons wi,th at(v* * * **

. . :: ca.kuJaHons :for both 'HE~ and LEU f:ue.L* * * .. * * < * . * * . . . .. ** * ' . . **** ..

• '***** *,..: > ., O \',*'I",', .., l 1" '* ',, *: I,::,,*, *, e * * .**., ,. ,*,<<-: '\,

• I , ; .~-.:c ' :. *..:~ ; * ..*' * ' , .. *. ,:*,_, * ,.: ,,.*,. *, .,., ~ * ,***, ***:-*:" .. :. *.. *.

• 9*... *t9n1p~f1~J,h .Qf t.M v~rH>µ$ tesults / .anp ..~1~,u~:i1;t>n* oftij*e :¢:.oq>,f.{$9nl * .... ** *

, . .* , * . * :* 1T.1.c..W9:1 r,g .~n.; ,xp lJn~~iqry ;t>f ~N' :.s ign.ift~~nt ~iffe.r~~¢.~s .. which ~~Ye: ~n .. : .

• • *: : *1mt>att on bqth: norma.1.:oper~t.1PiJ .Md. polentiJJ* ~~c1detits *wl.th 1~* :.reac~Qr.. *.

L?),;.,: * , %.. ,;tfftfflt*:11imtfKtti*i~~~~t,~iift1,~,~tii~~l~J!,.,~tprtt)!ito. :* *. : *--~-::*:\;

..

.< .. *.:* ,,o,t.*rieHl~el,adltlo11l~*:anrl'riFedAtU6rr\ittti *veHrlcaHo*ntiiftinal**: * ,

• ,'./:~:'*"/* . ,; '. ;~~,n~:elity_icqti'ditipn~. :* . : ,*. : , ' ...... ' ;* . . :**. *. '

~d(':\~: *-:/1,::::*:~;..;;<.:'*i;.*:**... i* . -~*,>.. *:.:* ; h ** * * ). ;:/ *,' **

.. /. ~/*./.*_._.. _::;.,.