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# OAR Box 1790 Prepped by Keeia Richards



### Document

Number: 

# 215 ) ll-F- 4
Docket Number: 

# A-90-3 7

Printed 10/31/2008 12:43:16

PM Sheet 215 of 250P. 2

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\ p qo tt ° UNITE D STATE S ENVIRONMENTA L PROTECTIO N AGENCY Offic e o f Ai rQualit yPlannin g an d Standard s Researc h Triangl e Park , Nort h Carolin a 2771 1 

# ?0'3 

# 7

MEMORANDU

M

DATE : Octobe r 23 , 199 2 SUBJECT : Propose d Rulemakin g o n Bes t Availabl e Contro l

Technology(BACT- ) L
FROM :

TO : Ai r Docke t A-91- 3 0 Davi d Solomo r Ne w Sourc e Re'vie

w Sectio n (MD-15 )

Th e attache d hand-writte n markup wa s receive d fro mth e Offic e o f Managemen t an d Budge t (OMB ) an

d reflect s thei r comment s t o EP Ao n th e draf t propose d rulemakin g o n BAC T whic h wa s submitte d t o OM B fo r interagenc yrevie w o n Octobe r 2 , 1992
. I n addition , attache d ar e tw o page s o f type d insert s tha t wer e dictate d t o Mr
. Gre g Foot e o f EPA' s Offic e o f Genera l Counse l durin g discussion s o n th e rulemakin g betwee n Mr
. Foot e an d Mik e Shapir o o f EPA' s Offic e o f Ai r an d Radiation , an

d Bo b Raine y o f th e Departmen t o f Energy , Ra ySquitier i o f th e Counci l o f Economi c Advisors , an d Davi d Rivki n o f th e Counci l o n Competitivenes s o n Octobe r 14 , 1992
. Attachment s


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### 1 3 assig neac ho f thes e factor s i n decidin g amon g options. ' Second , i t i s als o clea r tha t Congres s believe dtha t on e o f th e advantage s o f Stat e flexibilit y voul db e t o spee du p th e adoptio n o f advance s i n contro l technology. 4 

### Th e exercis e o f discretio nvithi nthes e bound s ca nb e fulfille db y

aor e tha non e aetho do f determinin g BACT . Regardles s o f th e specifi c methodology use dfo r determinin g BACT , b e i t top-down , th e metho dembodie di n th e 197 9 guidance , o r otherwise , EP A

interpret s th e relevan t Ac t provision s a s embodyin g tv o cor e lega l criteri a tha t mus t b e satisfie di n an y

3w 

### Th e decisio nregardin g th e actua l implementatio no f BAC T i s a ke y one , an dth e committe e place s thi s responsibilit y vit h th e State , t o b e determine di n a case-by-cas e judgment . I t i s recognize dtha t th e phras e ha s broa dflexibilit y i n ho v i t shoul d andca nb e interpreted , dependin g on site . I nmakin g thi s ke y

decisio no n th e technology t o b e used , th e Stat e i s t o tak e int o accoun t energy,'environmental , an d economi c impact s an

d othe r cost s ofth e applicatio no f BACT . Th e veigh t assigne dt o suc hfactor s i s t o b e determine dby th e State . Suc ha flexibl e approac hallow s th e adoptio no f improvement s i n technolog y

t o become widesprea dfa r mor e rapidl y tha nvoul doccu r vit ha uniform

Federa l standard . Th e onl y Federa l guideline s ar e th e EP A ne v sourc e performanc e andhazardou s emission s standards , vhic hrepresen t a floo r fo r th e State 1 

### s decision . Thi s directiv e enable s th e stat e t o conside r th e siz e o f th e plant , th e incremen t o f ai r qualit y vhich.vil l b e absorbe db y an y particula r majo r emittin g facility , an dsuc hothe r consideration s a s anticipate dan

d desire deconomi c grovt hfo r th e area . Thi s allow s th e State s and loca l communitie s to judg e 'ho v muc ho f th e define dincremen t o f significan t deterioratio nvil l b e devote dt o an y majo r emittin g facility . If , unde r th e desig nvhic ha majo r facilit y propose , th e percentag e o f th e incremen t voul d effectivel y

preven t grovt hafte r th e propose dmajo r facilit y va s completed , th e Stat e o r communit y coul drefus e t o permi t construction , o r limi t it s size . Thi s i s strictl y a Stat e an

d loca l decislon

H

### <ft[see

_Sen . Rep . No . 95-217 , 95t hCong. , 1s t Sess . 21 (l§7Tn> A * c* u***<** , iv

% *Mfv*vtW

,}MX ,,*W*« * eleA- L MAA-XCM'S- ^ *-#* *M>dLcf

4* _._f\u«

I WJ*UU* ^ tf

t^fyj^x- CUMADAJV * TVCM hi <LxtUmi 4>aJL *uu L 4 

### Se e als o statemen t o f Senato r Muskie , 12 3 Cong . Rec . S917l7d_^ » (Junes , 1977) . £fipP. 5

1 4 BAC T analysis. 5 First , th e permi t applican t mus t conside r a representativ

e grou p o f availabl e contro l technologie s [i.e. , technologie s tha t ar e representativ e o f the rang e o f availabl e control s tha t ar e a t leaa t a s effectiv e a s the minimu

m permissibl e (NSP S limit , S 11 2 limit , or SI P limit)] . Second , selection o f a particula r contro l syste m a s BAC T mus t b e justified b

y a compariso

no f the candidat e contro l systems i n term s o f th e statutor

y criteri a an

d supporte

d b y the record i n
sucha vay

tha t th e basi s fo r the choic e o f BAC T fro m amon g the othe r candidat e systems i s apparent ' an d consisten t vit hstatutor y .criteria. * Th e EP A i s toda

y proposin

g guidanc e consisten t vit hth e PS D regulations . Th e EP A continue s t o recogniz e tha t the Ac t an d >ex\stin

g regulation s fo

r BAC T mandat e applicatio n o f the tv o cor e ^Application o f EPA' s earlie r top-dow n guidanc e ma

y have ha

d the unintende d effec t o f constrainin g Stat e discretio

ni nmakin

g BAC T determinations . Als o the Administrator' s decisio n i n Vnion County Resourc e Paeover

y Facility . PS D Appea l No . 90- 1 (Nov . 28 , 1990 ) a t \ , coul d b e improperly construe

d a s -precludin

g an y comparisonN^ f candidat e contro l technologie s i n light o f th e applicabl e statutor y factors. i Together , thi s may hav e created a

n undul y strongpresumptio n thatNthe_mos t stringen t leve l o f contro l i s BACT. , 'i n thi s regard , t o th e exten t tha t a rational e for th e rejection o f th

e nex t mor e stringen t alternativ e thanth e on e proposed als o provide s th e basi s fo r rejectio n o f othe r mor e stringen t alternatives , ther e i s n o nee d t o conduc t a separate , detailed analysi s fo r eac haor e stringen t option . T o give an example , assum

e tha t after examinin g a contro l optio

ni n detail , th e permitting authority accept s anapplicant' s proposa l t o rejec t a contro l option du e t o a nadvers e economi c impac t afte r considerin

g the energy , environmental , an d othe r economi c impacts \ o f tha t option . The permittin g authority

nee d no t conside r th

e othe r mor e stringen t contro l options 1 i n detail , i f i t conclude s tha t thei r associated energy , environmental,.an d economi c impact s do no t diffe r meaningfull y fro m th e contro l optio

n rejected .P. 6

1 6 control s UBing an incrementa l impac t analysi s an d applyin

g othe r statutor

y criteria , thos e decision s n o longer reflec t EP A policy . A s stated above , the primar y benefi t t o th

e top-dow

nmethodolog

y
va s tha t i t voul d ensur e applicatio n o f the BAC T cor e criteria ,
^ b y permittin

g authorities . Hovever , earlie r effort s ha d th e potentia l t o chil l th e ful l exercis e o f a State' s discretionlij ^ Min i M l iiii|i|Tr**rrTTT>-»fp

v ther e ye r ant^TJ undul y stron g presumptio

ni nfavor o f the mos t stringen t pollution contro l alternativ e available . B

y proposin

g t o promulgat e th e cor e criteri a (as/formulate d today ) b

y regulation , EP A believe s i t ha B adequatel y implemente

d th e Act , includin g th e congressiona l inten t tha t broa d discretio

nremai nvit hth e permittin

g authority . I n th e contex t o f earlier appeal s t o the Administrator , question s have arisenove r Stat e discretio n t o conside r th e incrementa l ambien t an d cos t impact s associate d vit hcertai n pollution contro l options , relativ e t o the othe r availabl e options , i n determinin g BAC T [se

e Columbi a Gul f TransmissionCo. . PS D Appea l No . 88-1 1 (Order , June 2 1 1989) ; Worl d Color PreBS . Inc. . PS D Appea l No . 88- 4 (Reman d Order,.Decembe r 13 , 1990)] . I n thos e decisions , th e Administrator determine d tha t the v+ C^wK^ r no Aii-H w environmenta l impact s pron g o f th e BAC T analysi s precluded A» t Qt*ftt o P$_ ) analysi s a s t o vhethe r us e of th e mor e stringen t contro l U^^ W N^wo* ^ alternativ

e voul d benefi t ambient ai r quality , o r vhethe r th e additiona l benefi t va s vorththe expense . However , th e Administrato r di d recogniz e that , unde r certai ncircumstances ,P. 7



### 1 7

suchconsideration s may be appropriat e unde r the economi c impact s prong o f th e BAC T analysis.Underlyin g thes e decision s va s the viev that , unde r th e Act , ther e i s a distinctio n betveenBACT , vhic hi s concerned vit hpollutio ncontro l technology , an d ambient impacts , vhic hrelate s t o overal l ai r quality [see 4 2 U.S.C . 7475(a)(3 ) an

d (4)]? | Whil e th e EP

A continue s t o recogniz e tha t BAC T i s primaril y directed t o technolog y selection , an

d tha t thi s i s somewha t distinc t fro

m impact s uponambien t ai r quality , EP A doe s no t believe th e Ac t or implementin g regulation s mandat e absolut e i * / separation o f th e tvo concepts . Rather , < th e selectio

nc f anf e W^W^M ? appropriat e technolog y a s BAC T i s sufficientl y related t o the ' ywnvtxj Act' s overridin

g concer

n vit hai r quality

tha t a permittin

g authorit y

may , i n it s discretio n an d a s par t o f it s overal l BAC T analysis, , conside r the relativ e ambien t impact s o f the availabl e contro l alternatives . Althoug hthi s type o f analysi s ma y occur unde r eithe r the economi c o r environmenta l prong o f the BAC T analysi s (thu s SfejS^frfeJS ? 1^.^ ^ <W * **>>>**) .-ftdmlnlfltraLog) , the permittin g authority

mus t continue t o conside r th e ful l rang e o f statutor y factor s befor e issuin g the ^„ . fina l permit . Thi s shif t i npolic y

i s cqfrslsten

t vit hth e overal l recognition tha t Congres s intende d tha t th e State s retai nP. 8



### 1 8 maximu m discretio nandflexibilit y i nmakin g BAC T determinations. 7 

### Eve nthoughState s hav e discretio nt o conside r incremental ambien t an deconomi c impacts , the y mus t als o consider ! jL/1 al l o f th e othe r statutor y factor s i nth e BAC T analysis . Thes e i^rjC/O 1 

### ^^'
can , fo r example , includ e consideratio no f sourc e specifi c C2- VTM factors , suc ha s locall y sensitiv e environmenta l resources ; fW« ' tjfj proximit y

t o Clas s I areas ; overal l incremen t management ; -md- /Lk^T _^rmtttActr"gf - Bcoondar y pelIntants,-nuiJ

hua photnr-hnmic.

_fiuatf, Pfo \)J hiiwo j ITII I 

### otphr

r firm s n f v1 nihilit y impairment. * Thus , a Stat e ma y no t rel y

solel y upo npre-se t ambien t impac t o r cost effectivenes s level s i nselecting BACT , bu t mus t justif y it s selectio ni nterm s o f al l th e statutor y factor s (althoughsuc h level s ma y

b e utilize db

y a Stat e t o assis t i t i nmakin g it s determination) . I na BAC T analysis , th e representativ e grou po f contro l

a

### technologie s initiall y considere dshal l includ e th e mos t

7 

### I nsuc hcases , th e analysi s shoul drel y o nth e mode l and mode l input s use di nconductin g th e requisit e PS D ambien t ai r qualit y analysi s (i.e. , th e determinatio n"tha t ne v emission s vil l no t caus e o r contribut e t o a violatio no f th e applicabl e NAAQ S o r PS D increments) . *Insom e cases , th e lac k o f comprehensiv e informatio no r modelin g tool s limit s th e applicatio no f suc hanalyses . Hovever , i nmakin g it s fina l BAC T determination , th e stat e i s no t constraine dby

limitation s t o modelin g technology o r th e difficult y

i nassessin g environmenta l impacts , i f a Stat e lack s th e abilit y

t o definitivel y

quantif y

th e impact s upo nai r qualit y o r ai r qualit y

relate dvalues , o r prefer s t o no t rel y upo nsuc h measures , i t nevertheles s retain s discratio nt o manag e it s ai r resource s throug hrelianc e upo nqualitativ e determinatio n o r reasonabl e approximatio ni nmaking it s fina l BAC T selection .P. 9

2 5
cases , becaus e energ y penaltie s or benefit s ca n usuall y

b e quantified i nterm s o f additiona l cos t o r incom e t o th e source , th e energ

y impact s analysi s ca n b e converte

d int o dolla r cost s and , vher e appropriate , b e factored int o the economi c impact s analysis . Indirec t energ

y impact s (suc

ha s energ

y t o produc e ra

v material s fo r constructio n of contro l equipment ) ar e usuall y no t considered . Hovever , i f th e permi t authority determines , eithe r independentl y

o r based o

na shovin

g b y the applicant , tha t an indirec t energ

y impac t i s unusua l or significant , th e indirec t impac t may

b e considered . The energ y impac t shoul d still , hovever , relat e t o th e applicatio no f th e contro l alternativ e an d
no t t o a concernove r energ y impact s associate

d vit hth e projec t i n general . Th e energ

y impac t analysi s may^als o a'ddress the concernove r the us e o f locally-scarc e fuels . Th e designatio n o f a scarc e fue l may

var y fro m region t o region , bu t i ngenera l a scarc e fue l i s one vhic hi s i n shor t supply locall y

an d ca nb e bette r used for alternativ

e purposes , o

r one vhic hma

y no t b e reasonabl y availabl e t o th e sourc e either a t th e presen t tim e o r i nth e near future . B . Environmenta l Impacts . Th e environmenta l impact s analysi s i n the BAC T evaluation proces s concentrate s o n collatera l environmenta l impact s du e t o contro l o f emission s o f th e pollutan t inquestion , sucha s soli d

or hazardou s vast e generation , discharge s o f polluted vate r fro mP.1 0

2 6
a contro l device , visibilit y impact s (e.g . visibl e stea m plume) , O M 4 tu. -tl, U^a4v^A^vW L (J^Wu T A^^UfiiLt M iwwW"6;f-fS - CAA,h_ L «M^* - o r emission s o f toxi c pollutants . Th e applican t shoul d Identify ^vJ«/ *
an y environmenta l impact s associated vit ha contro l alternativ e &U\Vfc'*'*

M • tha t hav e th e potentia l t o affec t th e selectio no r rejectiono f tha t contro l alternative . Potentiall y significant , secondar y environmenta l impact s mus t als o b e evaluated . Scrubbe r effluent , for example , ma

y affec t vate r qualit y an d lan d use , and , similarly , technologie s usin g coolin

g tover' s may

affec t visibility . Othe r example s o f secondar y environmenta l impact s coul d include hazardou s vast e discharges , sucha s spen t catalyst s o r contaminated carbon . Generally , thes e type s o f environmenta l
concern s becom

e importan t vhe nsensitiv e site-specifi c receptor s exis t o r vhe n the incrementa l emission s reductio n potentia l o f

on e contro l optio

ni s only

marginall y

greate r tha n the nex t aos t effectiv

e option . Th e BAC T decisio

n ca nconside r stat e policy decision s regardin

g us e o f th e availabl e ai r qualit y incremen t for futur e grovt han

d th e veighin

g of thi s factor . A s discussed above , th e direc t impac t o f the control s o nambient-concentration s OTI als o b e identified an

d considere

d i nth e BACT-'analysis. - Th e procedur e fo r conjJu£fcin^r--_Tr"5halysi s o f environmenta l impact s should^b^rmade base d o nconsideratio

no f site-specifi c cirCriam^Cances . I n general , the analysi s o f environmenta l impact s start s vit hth e identificatio n an d quantificatio

n o f th e solid , liquid , an

d gaseou s discharge s fro m th e contro l devic e (o r .. .


### -_'..a,.*.j« j i ^ i-J^m.. Mmt-n. *W_ L <&£**w\ /A*ft

_AJvctftM . f\ ^uflAwuW i m^oJuA* .

_P.1 1

2 7 devices ) unde r reviev . Regardin g secondar

y effects , a qualitative o r semi-quantitativ e screenin

g canb e performed t o
narro v th e analysi s t o discharge s vit hpotentia l fo r causin g advers e environmenta l effects . Next , the mas s an d compositio

no f
an y suc hdischarge s shoul d be assessed an d quantified t o th e exten t possible , based o nreadily-availabl e information . A s previousl y

aentioned , the analysi s nee d only addres s thos e contro l alternative s vit han y environmenta l impact s tha t hav e the potentia l t o affec t th e selectio n O E rejectio

n o f a contro l alternative * /Pertinen t informatio n abou t t environmenta l consequence s o f releasin g thes e material s s als o b e assembled . Thus , th e relativ e environmenta l impact s (bot hpositiv e an

d negative ) o f th e variou s alternative s ca nb e compared vit heachother . Als o th e generatio nor reductio

no f toxi c an

d hazardou s emission s using th e variou s BAC T alternatives , includin g compound s no t regulated unde r th e Ac t or th e PS D program , ar e considere d a s par t o f th e environmenta l impact s analysis . Pursuan t t o the EP A Administrator' s decisio ni n Nort hCounty Resourc e Recover

y Associates , PS D Appea l No.85- 2 (Reman d Order , June 3,1986) , a PS D permittin g authority,shoul d tak e int o accoun t th e abilit y

o f a give n contro l alternativ e fo r regulate d pollutant s t o affec t emission s o f pollutant s no t subjec t t o regulationunde r th e Ac t o r the PS D progra

m i nmaking BAC T decisions . Consequently , the affec t o f a givencontro l 

### rvJ*.P.1 2

2 8 alternativ

e upon th e emissio

no f toxi c or hazardou s ai r contaminant s mus t b e evaluate d i nconductin

g th e BAC T analysis . C . Economi c Impact s Thi s analysi s shoul d addres s th e economi c impact s associated vit hthe.cost s o f installin g an d operatin

g alternativ

e contro l systems . Normall y

th e submitta l o f ver y detailed an

d comprehensiv

e projec t cos t dat a i s no t necessary . - I nth e economi c impact s analysis , consideratio nshoul d b e given firs t t o quantifyin g th e cos t c f the variou s contro l options . Th e revie v shoul d include a complet e explanatio n o f procedure s fo r assessin g economi c impact s an d an y supportin

g
data " y«aAutfwU i O^amW ^ icu^v^vuAjs , Onc e th e contro l technolog y alternatives ^ an

d emission s performanc e level s have been identified , capita l an d annua l cost s
ar e developed . The djrec

_cos t for^eachcontro l alternativ e shoul d b e presented bot ho na nincrementa l an

d an overal l basis . investmen t costs , operatio n an d maintenanc e costs , an d annualize

d cost a shoul d b e presented separately . Annualized cost s ar e operatio

n an d maintenanc e cost s plu s depreciatio nan d interes t charge s o

n th e investment . Cost s shoul d be itemize d an d

4 explained . Credi t fo r ta xincentive s shoul d b o include

d alon g vit hcredit s fog produc t recover y cost s an

d by-produc t sale s generate d fro

m th e us e o f contro l systems , includin g th e sal e o f sulfur dioxid e allowance s unde r th e aci d rai n progra m an d othe r emission reduction credits . Th e lifetim e o f the investmen t shoul d b e stated . Wher e possible , cost s shoul d b e broken dow n* f* \ CXH^OT^J-KOK^**^- ^ C* s - ct ^ - f****^*%H

J^*jtsT*<rv*>~+*< : & of- &Cs /9/tCT

2 9 int o proces s chang e cost s (cost s o f les s pollutin g productio

n process ) an

d direc t pollutio

n abatemen t cost s (cos t of pollutio n contro l equipment) • Th e cost s o f ai r treatment , vate r treatment , an d soli d vast e disposa l shoul d b e presente d separately . Th e objectiv

e o f th e analysi s i s t o provide a realisti c estimat e o f th e cost s o f the alternativ e technologies . A s a guid e i n determinin g vhe n contro l cost s becom e excessive , alternativ e contro l system

s ca n b e compare

d i n terms
o f th e incrementa l cos t effectivenes s o f th e availabl e alternatlvesTl^liwevei^- a PAC T optio n cannot automa t ica-ll y be » —rejecte d simply

becaus e i t i s mere , oHponolva-c r les s "eos t offactivc " tha

n anothe r candidat o vhichrein s vo c mor e pollu.antT I State s ca n evaluat e whethe r the incrementa l cos t effectivenes s o f

a mor e stringen t optio n is appropriat e in light/o f i , ecmrt"BAO T T- detcrminatioiku awf ] other factor s involve d in th e BAC T decision
an d th e State' s veighin g "'o f thes e factors . Incremental , cost effectivenes s calculation s ar e generall y performed o

n th e basi s €Lr^4JjtCey4.aJy ' of incrementa l dollar s pe r ton o f pollutant removed . 

### A I n additio

n t o th e type s of economi c impact s discusse d above , EPA

i s toda

y solicitin

g comment o

n vhethe r th

e economi c impact B analysi s shoul d conside r a s impacts.th e affordability

of control s b

y the fir

m i n respons e t o alternativ e level s o f control . Fo

r example , a mor e costl y BAC T alternativ

e coul d be presente d a s alterin g th e economic s o f a projec t t o th e poin t vher e a decisio

n voul d b

e mad e t o cance l th e constructio

n or expansio

n o f a facility , t o relocat e a plant,,t o reduc e th e scal e P.1 3P. M

3 0
o f operation , or t o chang e th e productio

n mix . I nsuchcases , th e loca l economi c impact s o f suchdecision s (e.g. , loca l employmen t effects , includin g numbe r o f jobs , dollar s pai d i n salaries , an

d change s i n employe e skil l level s required ) voul d b e evaluated an

d factored int o the economi c analysis . Comment s shoul d addres s th e reasonablenes s an d practicality

o f including A -ft
. suc hconsideration s i nthe BAC T analysis .

IV . Purpos e o f th e Propose d Change Th e approache s se t fort hi n the variou s EP A fina l an

d draf t guidanc e document s hav e bee n intended t o guid e permi t applicant s
an d permittin

g official s in thos e area s subjec t t o th e Federa l PS D regulation s a t 4 0 CF R52.21 . The

y hav e no t established bindin g regulator

y requirements , i hic har e containe

d i n th e Federa l regulation s an d SIP's . Rathe r tha nspecifyin

g a precis e approacht o the BAC T analysis , EP, * i s proposin g toda y t o clarify tv o cor e lega l requirement s tha t are necessar y fo r a n adequat e BAC T analysi s unde r existin g lav . I

nrevievin

g ne v or revised Stat e PS D rule s submitte d fo r SI P approval , the Agenc y vil l dee

m th e progra

m t o b e adequat e i f i t specifie s tha t thes e tv o t requirement s ar e necessary.fo r an adequat e BAC T analysis . Likevise , i n fulfilling-it s oversigh t an d enforcemen t responsibilities , th e Agenc y vil l continu

e it s polic

y o f revievin

g specifi c permittin g action s fo

r conformity

vit hth

e
cor e criteria . S o lon g a s th e Stat e ha s carefull y evaluated eac

h candidat e system , justifie d the choic e of on e ove r eac ho f th

e3 1

other s i n terms o f th e statutor y criteria , othervis e follove d the procedura l norms embodie d inthe cor e criteria , an d ensure

d th e decision voul d no t violat e an y objectiv

e standard s tha t ma y appl y (suc ha s NSP S o r SI P limits) , EPA vil l conside r a State' s BAC T analysi s t o b e adequat e an d vil l no t second-gues s th e State' s substantiv

e BAC T decision . Thus , unde r today' s proposal , adherenc e t o an

y specifi c BAC T approach , suc ha s top-dow

n o r bottom-up , i s no t required . Rather , today' s proposa l i s intended t o ensur e adherenc e t o th e cor e criteri a suc htha t State s aak e
reasone d an

d informe

d BAC T determination s i na publicly accountabl e manner . Further , th e State s have vid e discretio ni n settin g th e veigh t assigne d t o eac hstatutor

y facto r (energy , environmental , economi c an d othe r costs ) i ncomparin g an d balancing the relativ e effect s o f the variou s BAC T options . Whicheve r approachi s selected , th e BACT.analysi s shoul d include
a complet e explanatio no f the procedure s v.se d b y th e Stat e t o
asses s th e energy , environmental , an d economi c impact s an d an y supportin

g data . Permit s containin g BAC T determination s tha t d o
no t confor

m t o the PS D requirement s o f th e Act , EP A regulations , an d applicabl e SIP's , a s reflected inthe cor e criteria , vil l b e r ' considered deficien t b y EPA . Instance s o f procedura l / " irregularitie s o

r arbitrar

y decisio

n makin g vil l remai n ground s for/EPft-sofcioj?* , a s appropriate . Th e EP A i s toda

y solicitin

g comment o

nth e proposed clarification t o the BAC T definitio nfo r the purpos e o f clarifyin

g an d delineatin

g the regulator

y standar

d b y vhic hth

e

-P.1 6



### INSER T FOOTNOT

E O N P.1 7 EPA' s 197 9 guidanc e discussedthe us e o f affordabilit

y analysis

. During th e earl

y 1980 % thi s wa s permitte di n som e case s an dno t others

. However , i n 1987 , EP A 

### adopte daunifor

mnationa l polic y tha t affordabilit

y shouldno t

b e afacto r in BAC T analyses

. EP

A i s no w revisiting thi s issue

.P.1 7



### INSER T A S PAR

T OFFOOTNOT

E O N P

. 2 6 I n today' s rulemaking , EP A affirm s tha t

an y applican t

may provid e an inaementa l ambien t analysi s a s par t

o f it s BAC T submission , an di

f so , th e stat e shoul dconsider i t i n makin g aBAC

T determination

. Likewise , astat e ma y reques t suc h a n analysi s o f an y applican t

a s apar t o f it s BAC T process . Moreover , EP

A intend s t o provid e further guidanc e o n ho w tiies e issue s ma y b e addresse db y state s an dapplicants. '