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Avoid These Common Mistakes In Facility Design Most problems share one or more ofthese ten common denominators. Here's how to prelJenl such problems.

Willilm L Reewes. ESllnc. 01 Tennessee

54 •

MY l B ·

0

111,'

cannOi spend o\'er 20 years

in the planning. design. and construction of steam and co-

gcncr.lI;On fa<;ililies without seeing projects begin and e\'olve in nlany

different ways. l'rojeclS seem [0 either run like a Walch. or be a model for dcnJ(}flSu'lling most of Murphy's Laws.

This is true for many Olher Iy~ of chemical process indlL.... ries (CPI) fadlilies as wdl. Many of the problems thai plague lhe!;c 5IXmingly ditrlCult projects appear to be IOOl:cd in th::sJ. are .datal by a fl::'N oommon dcnominalors. For example•• '01'0 famili3f phntses have become IXlf1 of our e'''Cf)'tby mcabulary. When someone: ia)'5 -I need it )"CStenby!.- a m'id mernal picIun: appears that Iells us iI normal oouoc of evClltS is IlOII S3lisfaetory bocause lhis proj«t is a1tI:ady behind schedule. And

"'isukes

we '\'e all seen the canoon of 5CVa31 fllCa laughing wilh 11M: caption "You wanl i. when?!" Both of these phrd.'ie!l indic-"le thal schedule probkms exist that are most likely a direcl =011 of lack of planning and a SObSI:<IIN:nl lJte project st:01. This and Ihe remaining 0011"'1011 denominmOfS. which are undoubtedly equally familiar, are lisl~'d in the box on the nexl page. ReaJing that lisl probably scnt you on a trip down metTlOr)' lalle. Or po:ssibly the trip scem.:d more like a violent mugging in a d.1rJ( alley. This anicle presents our obsl.'l'WI;ons and experiences on why these mistalcs hJPPCn and the prtlblems they ~"'e. M~ importantly, il proVlOCs guiWnc1:: on how 10 a\"Qid these conunon mistakes..

ataICAI. EHGINE£IIHG I'lIOGlIESS

Some of the cxJmples deJI wilh steam Jnd !XJWcr plams, but the priociplcs apply jusl JS wcll to virtually all CPI facililies.

Schedule delays As mentioned earlier, when someollC say.s they "need il yeslerday:' schedule is already a p•.,blcm. E"en before the pr0ject gelS S1ar1l"d. sch.:dule problems exist Ihat precltKlc a normal or optimal COUI'lllC of C'O'ents bringing about satisfactory

oomplc'tion. By far. the II105l

fmjuenl

mislakc: ~

ing a l:lle st:lrI is failWl' 10 begin en\'ifQllmental pmnining early enough. In onJer 10 apply for an environmental oonsuuction pennit. the pcrf~ of a boiler sys!C1lI. including $learn conditions.. c;apacily. fuels fired. nlle-gas weights. and so on. muSl be est:lblished TiJMly ....uipmenl selections an: often not made because of lhe belief lhat equipment need only be selccl· ed in lime 10 meet the del;\"et)' requirenlC'nlS 10 satisfy the COIl.'\t1ll<.1ion schedule. SUbseqllCntly. when the project gets the "go-:lheJd" decision. the equipment has 10 be hurriedly selected in order 10 complelc the environmental penni! application. The problem now is Ihat the pennit pRlees.s wkes far longer thJn the engineering requirccl to begin sile worJ( and foundJliom, constroctioo. Many people are not aware that fedo.:r;lI law prohibits any pennanent ~'OIlstruetion 3l.1ivitic:s umil the construelion pennit is receival. A 'ubsequcnt deby in beginning concrete anti site ..."01'1;:: resullS in a IQl:II projc:l;t §Cbeduk: conlpre:Won. An initial delay in submining a permit application is

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u~lly

compountkd by !he lack of of lhe permitting ~.~ time ~iremet'l.~ espoci:Illy for ~­ lain Iypes cl permits sud! as lhosc reo quiring a Pre\~ntion of SigniflCaRl. DelCrior.IIion (PSD) review. k_~

When any lypo: of ap;ulSion ' . major moxIiflCa(ion is;\l'llicip;Ked. il i.~ ~3fly to contact thl: Ioc3.I air pmnilling agency 10 Ilcgin di5CllSSions lIbouI your p;lfticular pcnnil mluircmems. In order to OIeet the Kheduk requircmems. you may Ita\l: 1o hegin lite pennil process usin~ g~""ric infOI" matiOl1, inchlding perform;mce data, prior to management appro"'ll uf u projel:1 til' t,nul equipmenl ~1"""li"n,

never 100

Underestimating costs TIIC neXl mistake may remind us of lhe limes during our childhood years wilen we cr~wk.-d back 10 our parents to a.~k "Dad, ean )'<Ill spa"" aOOlhct' S20? I undcrwirnah:d wh:d. il \I.ouk! COS! 10 .. :'

Ceoainly any colllpany ...'OOld I'3thcr _ a project come in undc. budge! r:alhcr than O\'Cr budgel_ Rul gms.~. Iy O\~imalin1! :I projo:fs COSIS can

• 1:;1:'''' I. PrMIK,,1 '"g"."riIU i.. III, ul«lioft "M applK"'Um "f ,/im;""I, DptI'fJ/i..g ,,"" "''';''''''''''U probl,ms,

cuus.: other pmbk:ms. such a.~ crclJibilily of fuwn: approprimion r':'lue.sts, dcpri>';llion of capilal for ;lI101her nil;cal area nf Ihe business, and ~(l nn, Thercfoo:, lhe dilemma alway.s exists th:,l a C:l1"131 blldgcl ""quesl must c"...:r prob;,ble c.... lIingencies yet n.... go O\'Crbo;mi. Wilh Ihat b'OOl in mind. il rcally is quile .• illlple 10 det'''''' lI"w you anl\'C aI StICh a figure. One muS! undcr.;tand CQlnplcldy rhe sl'l:citic projeel faluill:mcms and lhen usc a compelenl ""Urcc of COMin~ infc.malion 10 priI..... 1110: cnli~ Syslem. piC('(: by pk<;oc:.

The 10 most common mistakes in the design and construction of facilities. 1.

:z. 1 4.

, .... i1..-Hyl. or ""Too _ C""""n- WIly don Ihos _10 be 1M __ ,Idlt< .... 1M_~? "Old, C,,_ .... analNrS2O?".·1 dOM' 1.Mw , C_ _ "'l· How don a ~nbo.d budttl .. dill ~ II a ptOIKI "" bt!ng a sa;. dift of ...NIl .-:I Wit.... Ihe "llf, u" good or So-and·So. TMy ~ a lmIoI bR lbout .. t<YIfIing: You -..Id not '10 111 a lIfIl"~ ptlClltlOlllt< II rou nelldad OlleR llean su'o.,.,. -I Illonk ~ should uH IIYl CO. l>eUUH ll>ty'tt biQglf end hi.. mort ,no...ctl: Tiley

"?

lion' 0111"'1' bO;gtr lII,n Ihl ttOo..IIlO",IRJl\IRI-IROUllh noel? 5. ·Surl WI Cln do tlll1- no p,at>ltmt· SOIIn<I the IllIm Ind flin til, big red fllg. 11'. ttl ,

I.

7. •.

t. III

JOIIgh ,ida ahead. -Soundi grin Givl ml one 01 rhon, InC need IU those opllons you mentioned: [quipmlnl is usull~ clplbt. of Plrforming whit it. Ol,g,nll dnign inluMed; tho IPIIlitOlioollS mOlt ollen tho proiJl..., work Oullhose del.ill in rlllf'lld: /l,ght' £X.tl~ who IS "wi- In\'WIY? ·h'. lilt. job hi worry lbou'lhl~ not OIl..." W. YOU' bOil WJIh you IIrer ...t\t<I lIfalll_ abouncl? "You cln PlY_'- or PlY .. lit..: The ,hIrty liNt Iht ... kll.re ...... ...,...,th.. oil fiII..1 tt~ ·r.... II wboI '/'011 _ W or II couAd do wtIy II C ",t '/'011 ~ _ _ lIbow and lItyand dol c.. II duty and lloo c _ $Ill tIWIU """',,, a

w,

-w.'.

...,

til,.

It'"

WIfI'••

-w. _ .....

lhtt,-

...,.i,....'..1......

If someone :lS~ ....1 you 10 give Itw:m a IJudgct pricc of a homc, il is impossible 10 do '" wilhoul a comprehensivc uooers/anding of what lheir c~pcclrr· tions an.: ;n a pcl'1'on;,1 rcsi,k:nl'e. One ,k~ rlOI go 10 the ban~ 10 horrow funds 10 build a IMltnc ooscd upon :I hOOgel estimalC .. f SX peT square fOOl. Li~c:wisc:, 'lCant and powc. pn>jecIS slMltlkI 001 be esIin\:lloo using SX per 1IMIU'land pounds o( 'leam or ~ilo­ wans. The: SWAG (Scienlific Wild A" Gues.') atlJllOOClt wilh adjUStmems '0 consider lTiajo," soopt' differenttS alll10Sl al.....ys I\$Ults in an unn:aliSiIc budgct - then: an: al....'3)'$ 100 many ilems lhal ....'t:R: 001 properly

_.

more dangerous 1If1ploxh 10 OOdgc1ing is It) baek<alculale 11M: capilal requirel1ll:l11 10 meeI certain pro forma financial rcquircmc:n1S.. Then. C\'efYtl'IIC goes 10 ...'Uft; 10 figure (JlI( hi.- K. build a ....vr1r:able sySlcm for lhal much <':lpilal. Thi., al'P"JllClt is 11 <.11rl1m0I1 problem, p;lftlcularly in priVillcly dc:.-elop.-d Ihird-p.lny projccu. Althouglt projcct~ can be t:ti1t~ 10 Illeet budg...1 lI.'quircmcnrs, <..... rtain objccli>'..., alit! swndards IIlU,t he cSlablished IJtofort' the design and pricing stan. TIlen, onc mUSl e~cn:ise discipline 10 .....sisl lllC lcmpl;nitln 10 add oos!s ...·irh marginal benefits ..... elimi· nalc <.1."tly hut critical Ctlrl1roncnls. If you .....anl an :lCCUr~IC budge!.)'()U Itaw 10 perform SOI1lI: ba.<;ic minimum engineering 10 accurately dc:tcnnine lhe emi.... pn>jl"CI scope and price. You should usc 11 SOtIm: ..... It" has aperi· eOCt: 3SSC"11lbling c:omprdlc:nsive deA f:lr

~Ial

0l0CAI. ENGINE.EIllNG I'llllGRESS • JLU t!!I5 •

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55


ENERGY TRANSFER/CONVERSION

sign/tluild estim:lles on that specific Iype of projecI. Thesr companies are aware 0( all the linle things that are n«USafy to male a project ~ rut Simply adding logdhcr all the majcJI" tqJipmerll budge! qooQIions will alWlIYS resull in queslions bier. such as Mit doesn't come with thatT" Thesr liule SlIrpOses ullimalCly add up 10 large budge! problems. General practitioners When we have a specilic medical problem.....e go to a specialist who is trained and won~ daily ....ith that pan of the body and our specific problem. We do nOl go to a general practitioner who knows a little about everything. People have a teodc:llCy in business to u~ "general practiliooers" beeau~ it is easy and we derive comfOl1 working with someone ....e • "';,un 2. Ffli/un bqin Mviro"Itt,,,lof kllOW and lJUSl through ~ious /H_il/i", tori, '_til u til, IIWS' COtll_ deaJings. Maybe the pas! success caaJt of profrct thm:!$. wa<l predie:l1cd upon the fact thai the pefSOn was dealing in his or her panic• mosI of all. guide you past many ular field of e~peni!iC. of the common pilfalls due to their In the age 0( specwiz:f:ion. thttt specialized CJlperien= Choo:l6ing the right oonlr.lClOr and are qualified ~ and rompanies that specializ:e in almoQ ev.oryming. the right proja:t tram :Ife discussed further in (1). Designing and eonsuucting ueam and powet plants - or any CPt planI- is Bigge, is not no ditremlt Avoid the kmpIation 10 necessarily better use the same lirm that you have alWllys used for all types of projeds. just be~iost 0( us gmo' up belie>'ing that cause il is convenienI. II is not diRkul1 bigger is better. This is dangefWS think· to sean::h out inllCl'View. and dcYeIop a ing '-ausc il implies these resources rel:ttionsltip of lr\1Sl with a company ~ knowledgeable and effICient at your thai does exactly ....hal. you warJt done, specifIC reqU'rt:meIllS. The U.S. GoY. and only that type of \lr"Ol'l(. 00 a daily emment is one of the biggcsl organiza· tions known, with va.'\!. resources - and ba.~is. In lhe design and coostnlCtion of CPI projects. such lirms should: how effl'lCli~ is it at doing relatively • be well versed in cnvironlTlental small projects efficiently? regulations and requirements: The size or resources of a comp.my are olCaningless. unless you hope to • be knowledgeable about the win ~ubsequent litigation b.ltlles. The state-of-lhe-an. commercially availahle lechnology that will beSI lit your people. with lheir ulents and expertise. thm work on your project ~ tfle sin~i'ualion; gle most important factor 10 your soc• have an exa:llent cost database to quickly and occuratcly SlIpp1y budget «'S$. We have secn this fact demon0( linn price5 for lhe project; stl1llcd over and moer again. A crack learn of highly trained comOOl special· • provide you with occurale dccails ists c-.m perform diffICult tasks that a 0( a proposed project 10 meeI your IequirelllCfllS quickly; and large army cannot. Small sptriIliud

'0

56 •

JULy 1m. CIHCAl BGtiJlIrlG rfllXifESS

compuler anti .software companies have gllb/:lIed up martel share from giants with f. more n::soutttS. The lJooom line is that if )'QIl want to maU the righi decision. make sun: you chose people with the talents.. experience. and bdlavior that match your projl'lCI needs. They can be Wllfting for any sil~ company. Thn"e is one certainty though: The CEO of it $30 million per year company is going to be more coocemed with the succes.s of a $10 millioo contract than the CEO of an S800 million per year company. Each company's best poople an: going 10 be woning Olllheir largest contracts with their biggest custonll,.'TS.

EJ:cessive optimism The IiFth mistake is falling prey 10 the line "Sure we can do lh:tt, 1\0 problem!" 1llere are certainly many instances when this is trut:. HO'oVCver, il behooves you 10 know .... hen. The easy test is 10 simply ask "Where have you done exactly what yoo are proposing here anti who can I Utlk 10 about the succe:ssT If the anS'olll'el" to )'QIlr quc:slion is qualified. iI's time to begin performing detailod tcebnicaI analysis to dcfermine )'QllI" specific appIicaIioo ditrrrena::s and eftSlR that what you noaI done is. in fxt. no

probI<m. Sale:sprople are supposed 10 be "can-do- and optimistic; we exptC1 lhem 10 act Ihal way. When you seriously consider a panicular conll1lCtor or vendor. it is time to lalk to the people ....ho are ullimately responsi. ble for ensuring your proje<:1 will be successful. Thi~ is the time for you 10 ask probing lechnkal questions, such as "What type of problems have you experienced in the pust with this type projed [or p:lnicular product or applicatiool?" By the nature of the question. you are implying that the problem wa.~ overcome successfully. If the response is "We have never had a problem before." be skeplicaL E>-ery proj«t has pr0blem issues - the key is how severe anti what was done aboul them. Sin-

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eerity, honesty, and (hopefully) trust will be demonstrated by their sh~r­ ing with you an incidem they considered to be ~ problem. A common tangent 111 this line of thinking is related to the last mistake we discusscd. Thm is thinking th~t since ~ comp;my or m~nura<:turer is so large and has done so m~ny things. your ~pp1ic~tion or project must be no problem ~nd there is no cause for alann or rc~son to a~k penetnlting technical questions..11Jc courts are full of cases whereby re~1 problem, between large companies have reached an i1Tlp~sse. Winning the protracted litigation is not the definition of a sucees~ful project

An e:<mnp1e is im.utlicient induceddraft fan margins on wood-tired boilers. Variations in wood fuel moisture. a nonnal fact of everyday operation of wood-tired boilers, has a drJm~tic effect upon the induced-draft f~n rt:quirernenLs. This variation is often ignored. and it is not uncommon to find substantially undersized induced-draft fans on wood-fired boilers. Aoother e:<ample is that water-treatment systems are sorTlt'timcs ~igned for worst~a'" conditions, ",sulling in norm~1 oper.uing nows that are well below the minimum now for efficient operation. One needs hands-on e:<pt'rience to unden;wnd and design pmperIy for thes<: types of situ~tiuns

Misapplication of equipment

Neglecting the details

Another CQrnrlK,n mistake parallels Many of uS have heard s.onlL"One say '"We'll work out those details in the last one, but with a focus 01\ equipment selection and applic~tion. Virtuthe field.'" The problem is that nolx>dy knows who '"we'" is. If the people makally every piece of equipment ever invented or m~nufa<:tured was suit~hlc ing this statement had any intention or for the ~pplic~tion fur which it was knowledge of how to take care of those details, they would prefer to do it urigin~lly designed. I'roblcms occur now and ~void lhe problems a'Stx;i~ted bccau>c of misapplication or pushing with trying to do it in the field. This the design limitations to e:<pand the potential pruduct market until failure hccorocs imminent. A common application problem is sometimes that the people involved in specifying or selecting equipment have no real. fin;th~nd working knowkdge of the equipment or its proper appliemion. Consequently, they f~ll prey to buying needless bells and whislles. which might in fact cause more problem, thun Ihe vulue they hrin!: 10 the projL'Ct. Ao nample of this might be using e:<cessive instrumentation and controls that cause conlinual m~in­ tenance ~nd c~libration p",blems on a simple process while otfering no real benetit in monitoring certain process variables. All too often, the evcryd.1Y oper~t­ ing rt:lluirerTlt'nts th~t serioosly ~tJoct pcrfunnance dco;ign margins. materials of construction. and the like are not adequately unOerseooJ. In such • Fixure J. Failure ItJ handl~ fh~ many detilils in ca'C;. texthnok learning cannot sub-- Ih~ design p!las~ r~sulls in ~"ussiVf! casf and stitute for working c:<perieoce. schedule impucr..

st:ltement is simply an accepted way of passing the buck. Either they do oot k1lOW how to handle these det:lils. or they are hoping they can pass them off onto someone else. 11le reality is that they don-t get done until it's panic time. and then it is difficult to handle them properly. 11le secret to a really sm:cessful project is the efficient e:<eculion of all the lillie details. Define e~r1y wh~t det~i1s need to be worked oot and a"sign so,ocone to handle them in the design phase. If he or she is not tecltnically c~pablc of h~ndling them. tht:n tht:y are re,ponsihle 10 lind someone who is_ When the details are addressed, it is amazing how many other things not evell considered until then becomc issues and get resolved as a result of this type of focused effort. This kind of effort results in an clTcctive and workable design.

No one is an island lbe next mistake c~n be charJ<:leril.ed by the st~terTlt'nt '"It's their job to worry about that, oot ours:' Design and construction projects typically involve an owner. a design/build engineer and oontractor, many ditJerenl vendors, subeontractors, and so on. In the course of a complex project. it is natural to tend to your own COfltr3Ct rcspotlsibilies alKl not worry about somebody else's. 11le realily is that there are numenKiS interface points, and the other pilfty's handling of those interfaces might very well affect yoor abilily to e:<c<:ute and perform )·OUI scope of work. An e:<ample is the typical sepamtion of responsibilities to provide mechanical. electrical. and building alld foundation services_ If all parties under:stand the different requirements of the other disciplines, they can eoordinate their design effOTts to ensure that critical interfaces are halKlled. If your job is to supply and set equipment. and you have not ensured tlmt the concrete contractor has installed ~nchor bolls in the proper locations, yoor work e:<c<:ution and schedule will be af-

CHEMICAL ENGlM:ERlNG PROGRESS • JULY 1995 • 57 http://engineering.forumotion.info/


ENERGY TRANSFERICONVERSION

fcrted. '11Je bonom line is docd by a stat",meot like "We oever said it C1)uld do that the projecl as a whole is either a success or failthat!" TIle parties be<:ome locked in disagreemeot ure. The fa<:t that you are 001 contractually at lilUlt over an issue that is simfor why it is a bad project ply a maHer of poor comrnuoication of eXptXlais of little con>equence. In planning th", ex~"Cu­ tions. All of a sudden tiun of your scope of supeach pany thinks the other 10 be unrealistic and ply. you should make two of suspect integrity wilen. lists: I, How docs the work in fact, bOIh probably were operating under the of OIhers affect or integr.lt'" with mi",,? utmost sincere intentions. TIlere is no time wilen 2. How docs my work trust is greater between affect or integrate with • Figure 4: On a large projut, mutual undl!~IQ",Ii"g of/he two parties than at the m0OIhers? upulaliMs by 1M cMlracfing parties iJ crilicallO success. 'Ihese lists serve as rement of cont'..ICt signing. will be used? Prupcr applicatiun of The be~t way to avoid future di~put",s minders to cht..c k c"'rtain ddails and mctallurgy is ceMainly a critical factor. .stemming from unrealized expecta· interlaces with the OIher appropriate parties. In the project coordination • Can you talk to somcone who has tions is to ask "What could IX'Ssibly happen that would cause problems h~d thc same type of equipment in a meetings. you will look like the only similar applil'ation with long-tenn with OUT agreement. or cau>c you to be one who really know~ what h", or ~he is duing. success? dissatisfictl with our pcrlorrnance'r • What is the contractor's reputation Even though no one wants to discuss Price vs. cost poIential problems at this moment, it with regard to first cost competitivewill eliminate problems later with un1llc line from the commercial. ness vs. subsequent cont'..ICtor-initiat· "You can p;ly me now or p;ly me realized expectations. A fr~nk and I'd change orde""? • What has been the track record of later," dnes a great job of illu~trating open discussion will ensue regarding the ninth mistake. l1Jcrc arc very few the vendor or contractor in handling what is considered unacceplable. This warranty claims? Here again, it might discussion will give you tremendous buying d....cisions where first cost is the insight into the expectations of the be that the pockets are so deep that the only real cost consideration. Too freot!>cr party and allow you to avoid fumoney cannot be reachctl. quently. a Tt:(lue~t for proposal is based on perlonnance criteria. Unles~ one Referent-e 2 discusses how to set up ture conllicts. In ..,ffec\, yuu will be docs a thorough evaluation of all the and apply utility functions to select prenegotiating pmhlem areas !>cfore capital equipment. they ever become a problem. ED panllncters involved in the equipment anti contractor boying decisions. most TIle selection of a de~ign anti conlikely the bidder with the lowest prit-e structioo linn is usually most heavily To receive a !rea copy oftlli$ article. weighted upon the initial price and send in tha lleadallnquiry Card in !his - and nOl necessarily the least costwill get the bosincss. evaluation of the technical offering. issue Wilh lhe No. 143 circled. Critical information to be evaluated Essentially. a major decision is being made to enter into a m~rriage with critmight include: ical expectalions_ You are wise to un• Wh~t types. thicknesses. and W. l- RE£VlS. P_E.. i$ the pr_nt of ESII.... 01 weights of materials of construction dCrstWld and agree with the principles Tt<'IM...., K."""uw, GA I~·ZS'Z or 4tl4,'41J.fi200: F.x: 4tl4,'4Zi-Jr>SOI•• d.~rVbuiId anti belief systems of the people with ""'1''''''_ ..., ,o"""'""'llirm ..I'o'io<l the whom you are going to do busi""".

Literature Cited

I.

It...... itz. B. A.,

"K«p

Auil. the Hun

Off Yoor f'rojc.:l." Chem. Eng. 1"1W"".

9t(4). pp. ]7--41 (Apr, t995). J. B.• -U", Utility

2. Chri>1i.an,

Fuoc'iom

Sele<:t Equipmem:' CNm. &Ix. I'rog"'''. 91(3). pp, 92-94 (M.... t995).

to

58 •

JULY 1m.

CPl. H.

h., ..or ZO 1"'''' 01

.,per~.

Unrealized expectations

...... ,nd 0....""'.... of .... mond

TIle tenth mistake is by far the mO~1 common and causcs the most problems between any t"'iO contracting parties. When pmhlems arise. the source of frustration can usually be traced to unrealized expectations. Ilow often has a project been torpe·

1913 .. 0 _

CHEMICAl ENGINEERING PROGRESS

in tho

,og."""tion Sf'tom>. H. beQIn to, ,,,... "

.~ foo- Bob< .. ~ 1\ W'<Ox: ESI '0'. of T......,," " 19~. ond beoomu,.,id,o' 01 E$I "' t!lll4. H. hold' 0 BS in ol>oml<ll ~._ Irom tho Uni.-. 01 Ak1"" .nd ,nondod the uoollliYe Prog"m of tl>o NO<lh Co,..... G,t<luol. S,~ 01 Bu,.,....

"o~.d

_

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