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# OAR Box 1790 Prepped byKeeiaRichards



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# A-90-3 7

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### Jun e 24 , 199 1 Not e t o Ar t Fraa s Attache di s a revise ddraf t o f th e BAC T rulemakin g proposal
. Th e draf t include s response s t o th e Apri l 19 , 199 1 comment s a s wel l a s some othe r mino r wordin g change s fro mou r Offic e o f Genera l Counsel . Pleas e le t m e kno wi f yo uhav e an yadditiona l comments . W e woul dlik e t o procee dwit hpublicatio ni nth e Federa l Registe r a s soona s possible
. Pleas e distribut e th e packag e t o th e othe r intereste dpartie s a s yo u normall ywould
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# n June 25,199 1 Not e t o Howar d Gruenspech t Enclose di s a revise d draf t o f th e BAC T rulemaking proposal
. A e indicate

di n th e attache d note , w e ar e giving th e proposa l t o Ar t Fraa s for distribution
.
Mik e Shapir oP. 4

file:BACTRULE. 7 ENVIRONMENTAL PROTECTIO NAGENC Y 4 0 C F RPart s 51 , an d 5 2 Requirement s fo r Preparation , Adoption , an d Submitta l o f Implementatio n Plans ; Approva l an d Promulgatio no f Implementatio n Plan s AGENCY : ENVIRONMENTAL PROTECTIO NAGENC Y(EPA ) ACTION : PROPOSE D RUL E SUMMARY : T o improv e th e effectivenes s o f th e preventio no f significan t ai r qualit ydeterioratio nprogra mrequire d b

y Titl e I , Par t C o f th e CleanAi r Ac t (Act) , EPApropose s todayt o amend it s rule s t o clarif yth e regulatorydefinitio no f bes t availabl e contro l technolog y(BACT ) b

yadding languag e tha t elucidate s th e lega l requirement s fo r a BAC T analysis
. Th e ne w languag e specifie s tha t a BAC T analysi s mus t contai n th e following tw o cor e requirements : 1 ) th e determinatio nmus t conside r a representativ e grou p o f availabl e contro l system s fo r th e source , including th e mos t stringen t alternativ e available , an d 2 ) selectio n o f a particula r contro l systema s BAC T mus t b e justifie d i n term s o f th e statutorycriteri a an d supporte d b

yth e record , an

d mus t explai n th e basi s fo r th e rejectio no f th e othe r candidat e systems . I n addition , EPApropose s t o amen d th e regulation s defining BAC T t o reflec t th e chang e mad e b y§ 403(d ) o f Titl e IV o f th e Ac t Amendment s o f 199 0 t o th e statutorydefinitio no f BACT . Th e EPAi s soliciting publi c commen t o n th e propose d change s t o th e regulatorydefinitio n o f BACT . DATES : Comment s mayb e submitte d t o EPAa t th e addres s belo wo n o r befor e [6 0 day s fromdat e o f publication]
. Apubli c hearing i s schedule d fo r ... . Th e hearing mayb e cancele d i f n o speaker s hav e requeste d time t o presen t thei r comment s 1 5 day s prio r t o th e schedule d hearing date
. Writte ncomment s i nlie u o f testimon

yar e encouraged
. DOCKET : Supporting informatio nuse d i n developing th e propose d rul e i s containe d i n Docke t No . A-91-30
. Thi s docke t i sP. 5

STAF F DRAF T Jun e 20 , 199 1 D O NO T CIT E O RQUOT E availabl e fo r publi c inspectio nan d copying betwee n 8:3 0 a.m . an d 3:3 0 p.m . MondaythroughFriday , a t th e addres s liste d below
. A reasonabl e fe e mayb e charge d fo r copying
. ADDRESSES : Comment s mus t b e maile d (i nduplicat e i f possible ) to : EPAAi r Docke t (LE-131 ) , Attn : Docke t No . A-91-30 , room M

1500 , Watersid e Mall , 40 1 MStree t SW. , Washingto n D C 20460
. Th e publi c hearing wil l b e hel d
... . FORFURTHE RINFORMATIONCONTACT : Davi d Solomo n a t (919 ) 541-5375
. Person s intereste d i n attending th e hearing o r wishing t o presen t ora l testimon

yshoul d contac t Ms . JoAnnAllma n i nwriting a t th e U.S . Environmenta l Protectio n Agency , Offic e o f Ai r Qualit y Planning an

d Standards , Ai r Qualit yManagemen t Division , Mai l Drop 15 , Researc hTriangl e Park , Nort hCarolina , 27711
. SUPPLEMENTAR

YINFORMATION :

I . Background Majo r stationarysource s and majo r modification s ar e subjec t t o th e preventio n o f significan t deterioratio n(PSD ) revie w requirement s o f th e Ac t (Titl e I , Par t C)
. Asubjec t facilit y mayno t b e constructe d withou t a permi t tha t meet s th e requirement s o f § 16 5 o f th e Act . Th e curren t PS D progra mi s implemente d b

ytw o set s o f regulations
. Th e firs t se t o f regulations , 4 0 CF R51.166 , specifie s th e minimu mrequirement s tha t a PS D ai r qualit ypermi t progra munde r Par t C o f th e Ac t mus t contai n i n orde r t o obtai napprova l b yEPAa s a revisio nt o a Stat e implementatio n plan (SIP)
. Th e secon d set , 4 0 CF R52.21 , delineate s th e Federa l PS D permi t program , whic hcurrentl y applie s a s par t o f th e SI P fo r State s tha t hav e no t submitte d a PS D progra

mmeeting th e requirement s o f 4 0 CFR51.166
. Roughl y two-third s o f th e State s ar e implementing thei r ow n PS D program whic hha s bee n approve d b yEP Aunde r 4 0 CFR51.166
. Th e regulation s a t 4 0 CF R52.2 1 appl yi nth e remaining States , mos t o f whic hhav e bee n delegate d th e authorit yt o implemen t th e Federa l PS D program . Among othe r substantiv e requirements , th eP. 6

STAF F DRAF T Jun e 20 , 199 1 D O NO T CIT E ORQUOT E facilit ymus t appl yBAC T pursuan t t o § 165(a)(4 ) [se e als o 4 0 CF R52.21(j ) (Federa l regulations) , 4 0 CFR51.166(j ) (regulation s setting fort hth e requirement s fo r Stat e implementatio n pla n (SIP ) approva l o f a Stat e PS D program) , an d 4 0 CF RPar t 52 , Subpar t A- Subpar t FF F (variou s SI P requirements)]. * Emission s limitation s reflecting th e applicatio no f BAC T mus t b e se t fort hi n th e PS D permi t [ § 165(a)(1)]
. T o obtai na PS D permit , an applican t must , among othe r requirements , conduc t a n analysi s i n accordanc e wit hEPAregulation s t o ensur e th e applicatio n o f BAC T t o eac hne wo r modifie d emission s uni t [ § 165(a)(2 , 4)]
. Th e require d analysi s mus t addres s "the degre e o f continuou s emission s reductio n whic hcoul d b e achieve d b ysuc h facility " [ § 165(e)(3)(B ) an d 4 0 CF R52.21(n)(1)(3)]
. Th e ter m"bes t availabl e contro l technology " i s define d i n th e Ac t as : an emission s limitatio n base d o nth e maximu mdegre e o f reductio n o f eac hpollutan t subjec t t o regulatio n unde r th e Clean Ai r Ac t emitte d fromo r whic hresult s fro m an ymajo r emitting facility , whic hthe permitting authority , o n a case-by-cas e basis , taking int o accoun t energy , environmental , an d economi c impact s an d othe r costs , determine s i s achievabl e fo r suc hfacilit y throughapplicatio n o f productio nprocesse s an d availabl e methods , systems , an d techniques , including fue l cleaning , clea n fuels , o r treatmen t o r innovativ e fue l combustio n technique s fo r contro l o f eac hsuc h pollutant
. I n n o even t shal l applicatio no f "bes t availabl e contro l technology " resul t i n emission s o f an ypollutant s whic hwil l excee d th e emission s allowe d b yan yapplicabl e standard establishe d pursuan t t o sectio n 741 1 o r 741 2 o f thi s title
. Emission s froman y sourc e utilizing cleanfuels , o r an yothe r means , t o compl ywit hthi s paragraphshal l no t b e allowe d t o increas e abov e level s tha t woul d hav e bee n require d

1 Unde r th e Clea n Ai r Ac t Amendment s o f 1990 , i ncertai n circumstance s BAC T i s als o a requiremen t fo r obtaining a permi t unde r Par t D o f th e Act .P. 7

STAF F DRAF T Jun e 20 , 199 1 D O NO T CIT E ORQUOT E unde r thi s paragrapha s i t existe d prio r t o enactmen t o f th e Clea n Ai r Ac t Amendment s o f 1990
. [ § 169(3) , a s amende d b y§ 403(d ) o f th e CleanAi r Ac t Amendment s o f 1990]
. I n determining BAC T o n a case-by-cas e basis , th e reviewing authorit yevaluate s th e energy , environmental , an d economi c impact s and othe r cost s associate d wit heac ho f th e candidat e technologie s considere d i n th e analysis
. Th e reviewing authorit y the n specifie s th e emission s limitatio n fo r th e sourc e tha t reflect s th e maximu mdegre e o f reductio no f eac hpollutan t regulate d unde r th e Act , determine d t o b e achievabl e taking int o accoun t th e energy , environmental , an d economi c impact s an d othe r costs . I n n o even t maya technolog yb e selecte d tha t woul d no t mee t an yapplicabl e standard o f performanc e unde r 4 0 CF RPart s 6 0 (newsourc e performanc e standards ) o r 6 1 (nationa l emissio n standard s fo r hazardou s ai r pollutants)
. I n addition , i f th e reviewing authorit ydetermine s tha t ther e i s n o economically-reasonabl e o r technologically-feasibl e wayt o accuratel ymeasur e the emissions , an d henc e t o impos e an enforceabl e emission s standard , i t mayrequir e th e sourc e t o us e design , alternativ e equipment , wor k practic e o r operationa l standard s t o reduc e emission s o f th e pollutan t t o th e maximu m exten t [4 0 CF R52.21(b)(12) ; 4 0 CF R51.166(b)(12)]. 2 I n January1979 , EPAissue d "Guidanc e fo r Determining BAC T unde r PSD, " an

d i n Octobe r 198 0 issue d a "PS D Workshop Manual " (EP A450/2-80-081)
. Thes e document s outline d an approac ht o th e

2 Fo r example , i f a coa l storag e pil e emit s coa l dus t t o th e atmosphere , i t woul d mak e littl e sens e t o impos e an emission s standard , sinc e measuring th e amoun t o f coa l dus t rising of f th e pil e mayb e nearl yimpossible
. Amuc hmor e direc t approac ht o controlling emission s is , fo r example , requiring th e owne r t o we t th e coa l pil e periodicall yo r t o totall yenclos e it
. Thi s typ e o f operationa l standar d o r wor k practic e woul d b e equivalen t t o a n emission s limitatio n fo r th e purpos e o f th e BAC T requirement
.P. 8

STAF F DRAF T Jun e 20 , 199 1 D O NO T CIT E O RQUOT E BAC T analysi s i n whic hth e applican t wa s t o propos e a bas e cas e a s BACT , presen t mor e stringen t contro l alternatives , an d defend it s BAC T selectio n "demonstrating tha t eac halternativ e contro l system.. . woul d caus e unreasonabl e advers e energy , environmental , o r economi c impacts " (se e "Guidanc e fo r Determining BAC T unde r , PSD, " January4 , 1979 , a t 5-6)
. I n Jun e 1986 , EPAestablishe d a Ne wSourc e Revie wTas k Forc e t o addres s growing concern s abou t th e effectivenes s o f th e ne w sourc e revie w(NSR ) program s i n meeting th e statutory requirements , an

d t o recommend action s t o improve EPA' s exercis e o f it s oversigh t an d enforcemen t responsibilitie s i n implementing th e NS Rprogram . Amon g th e Tas k Forc e findings , base d o na comprehensiv e revie wo f numerou s PS D permit s issue d during th e previou s severa l years , wa s tha t PS D applicant s an d State s frequentl ywer e conducting inadequat e BAC T determinations
. I n numerou s instances , applicant s woul d propos e anemission s limitatio n a t o r nea r a n applicabl e ne wsourc e performanc e standar d (NSPS ) unde r § 11 1 o f th e Ac t a s th e bas e case , an d provid e littl e o r n o consideratio no f mor e stringen t contro l option s befor e settling o n th e propose d leve l a s BACT . State s typicall ywoul d accep t thes e determination s wit hlittl e o r n o independen t analysis , thereb yfailing t o fulfil l thei r responsibilitie s unde r th e Act . Th e Tas k Forc e pointe d ou t tw o basi c solution s t o th e problemo f inadequat e BAC T analysis
. On e wa s t o improv e implementatio n o f th e existing metho d s o that , i n practic e a s wel l a s i n theory , th e statutoryrequirement s woul d b e fulfilled
. Th e othe r optio nwa s t o cal l fo r an alternat e approac ht o th e BAC T analyse s i n th e expectatio n tha t it s interna l dynamic s woul d achiev e mor e effectiv e implementatio no f th e BAC T requirement s [se e generall y"NewSourc e Revie wTas k Forc e Report, " Fina l Draft , Decembe r 1986 , a t 25-28]
. I n th e meantime , i n anadjudicativ e decisio no nappea l o f a PS D permi t fo r a municipa l wast e combusto r (MWC) , th eP. 9

——STAF F DRAF T Jun e 20 , 199 1

D O NO T CIT E O RQUOT E Administrato r hel d tha t a PS D applican t ha s th e "burde n o f demonstrating tha t significan t technica l defects , o r substantia l loca l economic , energy , o r environmenta l factor s o r othe r cost s warran t a contro l technologyles s efficien t tha n[the mos t stringen t technolog yavailable]. " Honolul u Resourc e Recovery Facilit y("H-Power")
. PS D Appea l No . 86-8 , a t 7 (Reman d Order , Jun e 22 , 1987)
. Shortl ythereafter , EPAissue d guidanc e calling fo r applicatio n o f th e H-Powe r holding t o al l BAC T determination s fo r MWC s ("Operationa l Guidanc e o n Contro l Technolog yfo r Ne w an d Modifie d Municipa l Wast e Combustors, " Jun e 26 , 1987)
. Subsequen t t o thes e events , EPAdecide d t o promot e wha t ha s come t o b e know

n a s a "top-down " BAC T metho d fo r al l categorie s o f PS D sources . I n brief , th e top-dow n proces s provide s tha t availabl e contro l technologie s b e ranke d i ndescending orde r o f contro l effectiveness
. Th e PS D applican t firs t examine s th e mos t stringen t alternative
. Tha t alternativ e i s establishe d a s BAC T unles s th e applican t demonstrates , an d th e permitting authorit y i n it s informe d judgmen t agrees , tha t technica l considerations , o r energy , environmental , o r economi c impact s o r othe r costs , justif ya conclusio n tha t thi s technolog yi s no t "achievable"
. I f a particula r technologyi s deeme d no t t o b e achievable , the n th e nex t mos t stringen t alternativ e i s considered , an d s o on . I n a Decembe r 1 , 198 7 memorandum , EPAHeadquarter s requeste d it s Regiona l Office s t o us e a top-dow nmetho d i nthei r ow n BAC T determinations , an

d t o encourag e Stat e an d loca l PS D permitting authoritie s t o d o s o a s wel l (se e Decembe r 1 , 198 7 memorandu m fromCrai g Potter , Assistan t Administrato r fo r Ai r an d Radiation , entitle d "Improving Ne wSourc e Review")
. Th e memorandu m furthe r directe d Regiona l Office s t o conduc t timel yreview s o f PS D applications , an

d t o commen t adversel yo npropose d PS D permit s tha t faile d t o adequatel yconside r contro l option s mor e stringen t tha n NSPS , a s woul d b e require d a s a matte r o f cours e i nan y acceptabl e metho d o f determining BACT . I f fina l Stat e an d loca lP.1 0

STAF F DRAF T Jun e 20 , 199 1 D O NO T CIT E O RQUOT E permit s stil l faile d t o reflec t adequat e consideratio no f th e relevan t BAC T factors , th e Region s wer e t o conside r suc hpermit s deficien t an

d conside r appropriat e enforcemen t actio n unde r § § 11 3 and 16 7 (i n th e cas e o f State-issue d permits ) o r appeal s t o th e Administrato r unde r 4 0 CFR124.1 9 (in th e cas e o f Federa l permits ) t o remed

ysuc hdeficiencies
. I n th e spring o f 1990 , EPA mad e availabl e t o th e publi c a draf t document , entitle d "Top-dow n Bes t Availabl e Contro l Technolog yGuidanc e Document, " detailing th e top-down BAC T method
. I n recommending th e us e o f th e top-dow napproach , EP

Adi d no t chang e th e existing PS D regulations , no r di d i t alte r th e BAC T requirement s fo r an ysource . Th e definitio no f BAC T i n th e statute , EPAregulations , an d SIP s remaine d th e same . Th e top-dow n approac hsimpl yrepresente d on e acceptabl e approac hfo r carrying ou t th e existing statutoryan d regulatoryrequirement s i n orde r t o assur e tha t theywoul d b e full yeffectuated
. O n Marc h29 , 198 9 (supplemente d o nMay3 an d 10 , 1989) , th e America n Pape r Institut e an d th e Nationa l Fores t Product s Associatio n (collectivel y"API" ) petitione d EPAt o rescind th e top-dow n policyan

d initiat e a rulemaking on BAC T determinations
. Th e EPAdenie d thi s reques t o n May12 , 198 9 (supplemente d o n Jun e 13 , 1989) , explaining tha t th e top-dow napproac hwa s no t a t varianc e with , no r a revisio n of , th e PS D regulations , an d tha t n o rulemaking wa s required
. Subsequently , AP I file d sui t i n th e D.C . Circui t an

d i n th e U.S . Distric t Cour t fo r D.C . AP I v . Reilly
. D.C . Cir
. No . 89-142 8 (filed 7/10/89) ; AP I v . Reillv
. D.C . Cir
. No . 89-203 0 (filed 7/18/89)
. A consortiu

m o f utilitie s als o file d a petitio nfo r revie wo f EPA' s actions , Alabam

a Powe r Co . v . EPA f D.C . Cir
. No . 89-142 9 (filed 7/11/89) , an

d th e cas e wa s consolidate d wit hth e AP I case . Th e same consortiu

m file d an administrativ e petitio nwit hEPAon February1 , 1990
. Finally , AP I als o challenge d th e 199 0 EPA draf t guidanc e documen t o n top-dow nBACT , AP I v . Reilly f D.C .P.1 1

STAF F DRAF T Jun e 20 , 199 1 D O NO T CIT E O RQUOT E No . 90-136 4 (filed 7/13/90)
. Settlemen t negotiation s currentl y ar e underwayregarding thes e cases . Th e EPAha s decide d a s a matte r o f policyt o conduc t thi s propose d rulemaking t o facilitat e greate r publi c participatio nconcerning thes e issues , notwithstanding EPA' s positio n tha t i t i s no t legall yrequire d t o d o so . II . Lega l Requirement s fo r a PS D Analysi s I n adopting th e PS D program , Congres s emphasize d th e importanc e o f thoroughan d publi c analyse s i nPS D decisionmaking , stating tha t on e o f th e purpose s o f PS D i s t o assur e tha t an y decisio n t o permi t increase d ai r pollutio ni n an yare a t o whic h PS D applie s i s mad e onl yafte r carefu l evaluatio no f al l th e consequence s o f suc ha decisio n an d afte r adequat e procedura l opportunitie s fo r informe d publi c participatio ni n th e decision

making process . A s note d above , § 16 5 specifies , an d EPA regulation s reflect , th e requiremen t t o conduc t a BAC T analysis
. Th e statutoryemphasi s o n procedura l rigo r i s accompanie d b y expression s o f congressiona l inten t tha t State s hav e wid e discretio n i n setting fina l emission s limit s reflecting BACT . State s als o hav e considerabl e discretio ni n othe r aspect s o f th e PS D program , suc ha s allocatio no f th e availabl e increment
. Fo r example , State s coul d choos e t o allocat e th e incremen t o na first-come first-serve d basis , preserv e a portio no f th e incremen t t o accommodat e futur e growth , o r allocat e incremen t througha marke t base d approached
. Th e legislativ e historyo nBAC T make s i t clea r tha t Congres s mean t th e Stat e t o mak e th e fina l substantiv e decisio no nth e appropriat e leve l o f technology
. Th e keypassage s o f th e Senat e repor t sho wtha t th e Stat e ha s broa d flexibilit yt o exercis e it s judgmen t i n implementing BACT . Th e repor t states :

Th e decisio n regarding th e actua l implementatio n o f bes t availabl e contro l technologyi s a keyone , an d 8P.1 2

STAF F DRAF T Jun e 20 , 199 1 D O NO T CIT E O RQUOT E th e committe e place s thi s responsibilit ywit hth e State , t o b e determine d i na case-by-cas e judgement
. I t i s t o b e recognize d tha t th e phras e ha s broad flexibilit yi n ho wi t shoul d an d canb e interpreted , depending o n site
. I n making thi s keydecisio no nth e technolog yt 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 o f th e applicatio n o f bes t availabl e contro l technology
. Th e weigh t assigne d t o suc hfactor s i s t o b e determine d b yth e State . Suc ha flexibl e approac hallow s th e adoptio n o f improvement s i ntechnolog yt o become widesprea d fa r mor e rapidl ytha n woul d occu r wit ha uniformFedera l standard (emphasi s added)
. [ S Rep . No . 95-217 , 95t hCong. , 1s t Sess . 3 1 (1977) ] Th e Senat e Repor t languag e suggest s tw o importan t bound s o nth e exercis e o f th e discretio n afforde d t o th e permitting authorit y i n determining BACT . First , i t i s clea r tha t i nadopting BACT , Congres s intende d PS D permitting authoritie s t o exercis e informe d discretio n t o weighenergy , environmental , an d economi c impact s i n determining BAC T fo r a particula r source . Second , i t i s als o clea r tha t Congres s intende d on e o f th e advantage s o f Stat e flexibilit yt o b e t o spee d u p th e adoptio no f advance s i ncontro l technology. 3 Th e exercis e o f discretio nwithi n thes e bound s ca nb e fulfille d b

ymor e tha n on e metho d o f determining BACT . Regardles s o f th e specifi c methodolog yuse d fo r determining BACT , b e i t top-down , th e metho d embodie d i nthe 197 9 guidance , o r otherwise , EPAha s consistentl yinterprete d th e relevan t Ac t

3 Se e als o statemen t o f Senato r Muskie , 12 3 Cong . Rec . S917 1 (June 8 , 1977)
.P.1 3

STAF F DRAF T Jun e 20 , 199 1 D O NO T CIT E O RQUOT E provision s a s embodying two cor e lega l criteri a tha t mus t b e satisfie d i n an

yBAC T analysis
. First , th e permi t applican t mus t conside r a representativ e grou p o f availabl e contro l technologies , i.e. , technologie s tha t ar e representativ e o f th e rang e o f availabl e control s tha t ar e mor e effectiv e tha nth e minimu mpermissibl e ( NSP S limit , sectio n 11 2 limit , o r SI P limit) , including th e mos t stringen t alternative available. 4 Th e permi t applican t shoul d refe r t o th e BACT/LAE RClearinghous e whe n identifying a representativ e grou p o f availabl e contro l technologies
. Second , selectio no f a particula r contro l system a s BAC T mus t b e justifie d i n term s o f th e statutorycriteri a an d supporte d b

yth e record , an

d th e basi s fo r th e rejectio n o f th e othe r candidat e system s mus t b e explained. 6

4 Whethe r a technologyi s "available " fo r purpose s o f BAC T i s a practical , factua l determination , using conventiona l notion s o f whethe r th e technologyca nb e pu t int o us e [se e Pennsauke n County . Ne wJerse yResourc e RecoveryFacility , PS D Appea l No . 88- 8 (Reman d Order , Nov . 10 , 1988 ) a t 8]
.

^ Eac htyp e o f availabl e contro l system(e.g. , a baghouse , an electrostati c precipitator , a dryscrubber , a we t scrubber , a carbo n absorber ) o r combinatio no f contro l system s shoul d b e analyze d a t th e maximu mleve l o f contro l technicall yachievabl e fo r th e contro l system

o r combinatio no f contro l system s a s i t coul d b e applie d a t th e propose d facilit yi n question
. Majo r alternative s withi n a give n typ e o f contro l systemshoul d als o b e considere d whe n suc halternative s woul d produc e meaningfull ydifferen t energy , environmental , o r economi c impac t o r othe r cost s thanth e initia l leve l o f contro l analyzed
. Onth e othe r hand , analyse s o f numerou s mino r variation s i n a contro l system(or combination s thereof ) i s no t required
.

6 I n thi s regard , t o th e exten t tha t a rational e fo r th e rejectio n o f th e nex t mor e stringen t alternative tha nth e on e propose d als o provide s the 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 separat e detaile d analysi s fo r eac hmor e stringen t option
. T o giv e an example , afte r examining a contro l optio ni n detail , th e permitting authorit yaccept s an applicant s proposa l t o rejec t a contro l optio n du e t o a n advers e economi c impac t afte r considering th e energy , environmental , an

d othe r economi c impact s o f tha t option
. Th e

1 0P. M

STAF F DRAF T Jun e 20 , 199 1 D O NO T CIT E O RQUOT E Thes e tw o cor e criteri a ar e consisten t wit hdetermination s i n th e administrativ e appeal s decision s subsequen t t o th e H-Powe r decisio n a s being th e essentia l requirement s o f a BAC T analysis
. Thus , i n Unio n Count yResourc e RecoveryFacility , PS D Appea l No . 90- 1 (11/28/90 ) a t 8 , th e Administrato r cite d complianc e wit h th e tw o cor e criteri a i n upholding a BAC T determinatio n fo r a resourc e recoveryfacility
. Th e Administrato r relie d o n th e same tw o cor e criteri a i n upholding a permi t determinatio ni n Mecklenbur g Cogeneratio n Limite d Partnership , Clarksville
. VA . PS D Appea l No . 90- 7 (12/21/90 ) a t 6
. AlthoughEPAbelieve s tha t th e curren t statutoryan d regulatorydefinition s o f BAC T implicitl yrequir e th e consideratio n o f thes e tw o cor e criteri a a s fundamenta l t o an y adequat e BAC T determination , th e EPAi s toda yproposing t o mak e thi s requiremen t explici t b yinserting int o th e regulatory definitio n o f BAC T th e following tw o cor e requirement s fo r a BAC T analysis : 1 ) th e determinatio n mus t conside r a representativ e grou p o f availabl e contro l system s fo r th e source , including th e mos t stringen t alternativ e available , an d 2 ) selectio n o f a particula r contro l system a s BAC T mus t b e justifie d i n term s o f th e statutorycriteri a an d supporte d b

yth e record , an

d mus t explai n th e basi s fo r the rejectio no f th e othe r candidat e systems .

III . Impact s Analysi s i n a PS D Determinatio n I n orde r t o rejec t analternativ e contro l systeman applican t mus t demonstrat e th e advers e impact s whic hwoul d resul t fromth e selectio n o f tha t alternativ e system . Thi s sectio n list s some specifi c energy , environmental , an d economi c impact s permitting authorit ynee d no t conside r th e othe r mor e stringen t contro l option s i n detail , i f i t conclude s tha t thei r associate d energy , environmental , economi c impact s d o no t diffe r meaningfull y fro mth e contro l optio n rejected
. 1 1P.1 5

STAF F DRAF T Jun e 20 , 199 1 D O NO T CIT E ORQUOT E whic hmayb e addresse d i n thi s impact s analysi s an d explain s th e dat a requirement s fo r documenting anadvers e impact
. No t everyfacto r discusse d belo wneed s t o b e addresse d i n everypermi t application
. Rather , thi s discussio n present s a se t o f potentia l factors , an ynumbe r o f whic hmayb e addresse d i na permi t applicatio n depending o n th e individua l situation
. Fo r example , i f a contro l systemproduce s a know nquantit yo f soli d wast e a s a by-produc t inheren t t o it s designan d operatio n unde r norma l conditions , suc han impac t shoul d b e note d i n th e PS D permi t applicatio n . However , thi s facto r nee d no t b e analyze d i n detai l unles s th e applican t wishe s t o us e soli d wast e impact s a s an argumen t fo r o r agains t selectio no f a particula r contro l alternativ e a s BACT . I n general , th e BAC T analysi s shoul d addres s th e direc t (on

site ) impact s o f alternativ e contro l systems . Indirec t energ yo r environmenta l impact s ar e usuall ydifficul t t o assess , s o ar e no t require d bu t mayb e considere d wher e suc himpact s ar e foun d t o b e significan t an

d quantifiable
. Indirec t energ yimpact s includ e suc himpact s a s energyt o produc e rawmaterial s fo r constructio n o f contro l equipment , increase d us e o f importe d oil , o r increase d oi l us e i n th e utilit ygrid
. Indirec t environmenta l impact s include , suc hconsideration s a s pollutio na t anoff-sit e manufacturing facilit ywhic hproduce s material s neede d t o construc t o r operat e a propose d contro l system . Indirec t impact s generall ywil l no t b e considere d i nth e BAC T revie wsinc e th e complexit yo f consumptio n pattern s i nth e econom ymake s thos e impact s difficul t t o quantify
. Fo r example , sinc e manufacturer s purchas e capita l equipmen t an d supplie s fro

mman ysuppliers , wh o i n tur n purchas e good s fromothe r suppliers , accurat e assessmen t o f indirec t impact s mayno t b e possible
. Rawmaterial s mayb e neede d t o operat e contro l equipment , an d supplier s o f thes e resource s maychang e ove r time
. Similarly , i t generall ywil l no t b e possibl e t o determin e specifi c powe r station s an d fue l source s 1 2P.1 6

STAF F DRAF T Jun e 20 , 199 1 D O NO T CIT E ORQUOT E whic hwoul d b e use d t o satisf ydemand ove r th e lifetime o f a contro l device
. Duplicativ e analyse s generall yar e no t require d i npreparing th e BAC T permi t application
. An ystudie s previousl yperforme d fo r Environmenta l Impac t Statements , wate r pollutio npermits , o r othe r program s mayb e use d whe n appropriat e t o demonstrat e advers e energy , environmental , o r economi c impacts
. Th e same consideration s ar e generall yapplicabl e t o bot hne wan d modifie d sources . Wher e appropriate , however , th e permi t revie wmay conside r an

yspecia l economi c o r physica l constraint s whic hmigh t limi t th e applicatio n o f certai n contro l technique s t o a modifie d emission s unit , suc ha s retrofiting cost s tha t woul d no t b e born e b ya ne wunit , o r th e remaining usefu l lif e o f th e modifie d facility
. Th e resul t mayb e tha t th e leve l o f contro l require d fo r a n emission s uni t undergoing modificatio nmayno t b e a s stringen t a s tha t whic hwoul d b e require d i f th e same uni t wer e being constructe d a t a "greenfield " facility
. Suc hfindings , however , mus t b e mad e o n a case-by-cas e basi s b yth e permitting authorit yconsidering th e relevan t energy , environmenta l an d economi c impacts
. Th e energy , environmental , an d economi c impacts , discusse d belo war e illustrativ e onl yan d ar e no t intende d a s an exclusiv e lis t o f consideration s fo r BACT . Some o f thes e factor s mayno t b e appropriat e i n al l cases , whil e i n othe r instances , factor s whic har e no t include d her e mayb e relevan t t o th e BAC T determination
. Th e discussio n doe s no t addres s th e evaluatio no f eac hfacto r no r th e weighing o f an yfacto r relativ e t o another
. Suc hdetermination s shoul d b e mad e o na case-by-cas e basi s b yth e permitting authority
. Fo r th e purpos e o f thi s discussion , term s suc ha s "emissio n contro l system " o r "BACT system " refe r t o design , equipment , o r operating standard s an d inherentl yles s polluting processe s a s wel l a s add-o ncontro l equipment
. A . Energ

yImpact s 1 3P.1 7

STAF F DRAF T Jun e 20 , 199 1 D O NO T CIT E O RQUOT E Energ yimpact s shoul d addres s energ yus e i nterm s o f penaltie s o r benefit s associate d wit ha contro l systeman d th e direc t effect s o f suc henerg

yus e o n th e facility
. Asourc e may , fo r example , benefi t fromth e combustio no f a concentrate d ga s strea mric hi n volatil e organi c compounds ; o nth e othe r hand , extr a fue l o r electricit yi s frequentl yrequire d t o powe r a contro l devic e o r incinerat e a dilut e ga s stream . I f suc hbenefit s o r penaltie s exist , theyshoul d b e quantified
. I n quantifying energ yimpacts , th e applican t coul d estimat e th e direc t energ

yimpact s o f th e contro l alternativ e i n unit s o f energ yconsumptio n a t th e sourc e ( e.g. , Btu , kWh , barrel s o f oil , ton s o f coal)
. Th e energ yrequirement s o f th e contro l option s coul d b e show n i nterm s o f tota l and/o r incrementa l energ ycost s pe r to n o f pollutan t removed
. I nman ycases , becaus e energ

ypenaltie s o r benefit s ca n usuall yb e quantifie d i n term s o f additiona l cos t o r income 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 , wher e appropriate , b e factore d int o th e economi c impact s analysis
. Indirec t energ

yimpact s (sucha s energ yt o produc e raw material s fo r constructio n o f contro l equipment ) ar e usuall yno t considered
. However , i f th e permi t authorit ydetermines , eithe r independentl yo r base d o na showing b yth e applicant , tha t an indirec t energ

yimpac t i s unusua l o r significant , th e indirec t impac t mayb e considered
. Th e energyimpac t shoul d still , however , relat e t o th e applicatio n o f th e contro l alternativ e an d no t t o a concern ove r energ yimpact s associate d wit hth e projec t i n general
. Th e energ

yimpac t analysi s mayals o addres s th e concer n ove r th e us e o f locall yscarc e fuels
. Th e designatio no f a scarc e fue l mayvaryfro

mregio n t o region , bu t i n genera l a scarc e fue l i s on e whic hi s i n shor t suppl ylocall yan d canb e bette r use d fo r alternativ e purposes , o r on e whic hma yno t b e reasonabl y

1 4P.1 8

STAF F DRAF T Jun e 20 , 199 1 D O NO T CIT E O RQUOT E availabl e t o th e sourc e eithe r a t th e presen t time o r i nth e nea r future
. B . Environmenta l Impact s Th e environmenta l impact s analysi 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 i n question , suc ha s soli d o r hazardou s wast e generation , discharge s o f pollute d wate r fro ma contro l device , visibilit yimpacts , o r emission s o f toxi c pollutants
. Th e applican t shoul d identif yan yenvironmenta l impact s associate d wit ha contro l alternativ e tha t hav e th e potentia l t o affec t th e selectio n o r rejectio no f tha t contro l alternative
. Some contro l technologie s mayhav e potentiall ysignifican t secondaryenvironmenta l impacts
. Scrubbe r effluent , fo r example , mayaffec t wate r qualit yan d lan d use , and , similarly , technologie s using cooling tower s mayaffec t visibility
. Othe r example s o f secondaryenvironmenta l impact s coul d includ e hazardou s wast e discharges , suc ha s spen t catalyst s o r contaminate d carbon
. Generally , thes e type s o f environmenta l concern s become importan t whe n sensitiv e site-specifi c receptor s exis t o r whe n th e incrementa l emission s reductio n potentia l o f on e contro l optio n i s onl ymarginall ygreate r thanth e nex t mos t effectiv e option
. Th e procedur e fo r conducting ananalysi s o f environmenta l impact s shoul d b e mad e base d o n a consideratio n o f site-specifi c circumstances
. I ngeneral , th e analysi s o f environmenta l impact s start s wit hth e identificatio nan 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 device s unde r review
. Initially , a qualitativ e o r semi-quantitativ e screening canb e performe d t o narro wth e analysi s t o discharge s wit hpotentia l fo r causing advers e environmenta l effects
. Next , th e mas s an d compositio no f an ysuc hdischarge s shoul d b e assesse d an d quantifie d t o th e exten t possible , base d o n readil yavailabl e information
. A s previousl ymentioned , th e analysi s nee d onl yaddres s thos e 1 5P.1 9

STAF F DRAF T Jun e 20 , 199 1 D O NO T CIT E O RQUOT E contro l alternative s wit han yenvironmenta l impact s tha t hav e the potentia l t o affec t th e selectio n o r rejectio n o f a contro l alternative
. Pertinen t informatio n abou t th e publi c o r environmenta l consequence s o f releasing thes e material s shoul d als o b e assembled
. Thus , th e relativ e environmenta l impact s (bothpositiv e an d negative ) o f th e variou s alternative s canb e compare d wit heac h other
. Th e generatio n o r reductio n o f toxi c an d hazardou s emissions , including compound s no t regulate d unde r th e Clea nAi r Ac t o r 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 th e EPA Administrator' s decisio n i n Nort hCount yResourc e Recovery Associates
. PS D Appea l No.85- 2 (Reman d Order , Jun e 3,1986) , a PS D permitting authorit yshoul d tak e int o accoun t th e abilit yo 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 regulatio nunde r th e Clean Ai r Ac t o r th e PS D programi n making BAC T decisions
. Consequently , th e abilit yo f a give n contro l alternativ e t o contro l toxi c o r hazardou s ai r contaminant s mus t b e considere d i n th e BAC T analysis
. C . Economi c Impact s Thi s analysi s shoul d addres s th e economi c impact s associate d wit hth e cost s o f installing an d operating alternativ e contro l systems . Normall yth e submitta l o f verydetaile d an d comprehensiv e projec t cos t dat a i s no t necessary . I n th e economi c impact s analysis , primaryconsideratio n shoul d b e give n t o quantifying th e cos t o f contro l an d no t th e economi c situatio n o f th e individua l source . Consequently , applicant s generall yshoul d no t propos e eliminatio no f contro l alternative s on th e basi s o f economi c parameter s tha t provid e an indicatio n o f th e affordabilit yo f a contro l alternativ e relativ e t o th e source . Th e revie wshoul d includ e a complet e explanatio n

1 6P.2 0

STAF F DRAF T Jun e 20 , 199 1 D O NO T CIT E O RQUOT E o f procedure s fo r assessing economi c impact s an d an ysupporting data
. Onc e th e contro l technolog yalternative s an

d emission s performanc e level s hav e bee n identified , capita l an d annua l cost s ar e developed
. Th e direc t cos t fo r eac hcontro l alternativ e shoul d b e presente d bot ho n a n incrementa l an d a noveral l basis
. Investmen t costs , operatio nan d maintenanc e cost s an d annualize d cost s shoul d b e presente d separately
. Annualize d 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 b e itemize d an d explained
. Credi t fo r taxincentive s shoul d b e include d along wit hcredit s fo r produc t recoverycost s an d by-produc t sale s generate d fromth e us e o f contro l systems . Th e lifetime o f th e investmen t shoul d b e stated
. Wher e possible , cost s shoul d b e broke n down int o proces s chang e cost s (cost s o f les s polluting productio n process ) and direc t pollutio nabatemen t cost s (cos t o f pollutio n contro l equipment)
. Th e cost s o f ai r treatment , wate r treatmen t an

d soli d wast e disposa l shoul d b e presente d separately
. Th e analysi s shoul d als o includ e th e tota l investmen t cos t o f th e ne wfacility
. A s a guid e i n determining whe n contro l cost s become excessive , alternativ e contro l system s ca n b e compare d i n term s o f certai n cos t effectivenes s ratio s suc ha s incrementa l cos t effectiveness
.

IV . Purpos e o f th e Propose d Chang e Th e approache s se t fort hi n th e variou s EP Afina l an

d draf t guidanc e document s hav e bee nintende d t o guid e permi t applicant s an d permitting official s i n thos e area s subjec t t o th e Federa l PS D regulation s a t 4 0 CFR52.21
. Theyhav e no t establishe d binding regulatoryrequirements , whic har e containe d i nth e Federa l regulation s an d SIP's . Rathe r thanspecifying a precis e approac ht o th e BAC T analysis , EPAi s proposing todayt o se t ou t th e tw o cor e lega l requirement s necessaryfo r a n adequat e BAC T analysis
. I n reviewing ne wo r revise d Stat e PS D rule s submitte d 1 7P.2 1

STAF F DRAF T Jun e 20 , 199 1 D O NO T CIT E O RQUOT E fo r SI P approval , th e Agencywil l deemth e progra mt o b e adequat e i f i t specifie s tha t thes e tw o requirement s ar e necessaryfo r a n adequat e BAC T analysis
. Likewise , i nfulfilling it s oversigh t an d enforcemen t responsibilities , th e Agenc ywil l continu e it s polic yo f reviewing specifi c permitting action s fo r conformit y wit hth e cor e criteria
. S o long a s th e Stat e follow s th e procedura l norm s embodie d i nth e cor e criteri a an d doe s no t violat e an

yobjectiv e standard s tha t mayappl y(sucha s NSP S o r SI P limits) , EPAwil l conside r a State' s BAC T analysi s t o b e adequat e an

d wil l no t second-gues s th e State' s substantiv e BAC T decision
. Thus , adherenc e t o an yspecifi c BAC T approac hi s no t required
. Further , th e State s hav e wid e discretio ni n setting th e weigh t assigne d t o eac hstatutoryfacto r (energy , environmental , economi c an d othe r costs ) i n comparing an d balancing th e relativ e effect s o f th e variou s BAC T options
. On th e othe r hand , permit s containing BAC T determination s tha t d o no t conform

t o th e PS D requirement s o f th e Act , EP Aregulations , an d applicabl e SIP's , a s reflecte d i nth e cor e criteria , wil l b e considere d deficien t b yEPA . Instance s o f procedura l irregularitie s o r arbitrarydecisionmaking wil l remai n ground s fo r enforcemen t actio n o r permi t appeals , a s appropriate
. A s an example , a BAC T analysi s focusing o n a compariso n o f th e incrementa l impact s (energy , environmental , an d economic ) woul d b e appropriat e a s lon g a s th e Stat e had carefull yevaluate d an d justifie d i n term s o f the statutorycriteri a th e basi s fo r th e rejectio n o f th e othe r candidat e systems . Suc han analysi s coul d b e presente d i n th e for mo f th e incrementa l impac t o f alternativ e contro l system s relativ e t o th e systempropose d a s BAC T i n th e permi t application
. I nthi s exampl e th e economi c portion s o f th e analysi s coul d addres s th e economi c impac t associate d wit hth e incrementa l cost s o f installing an d operating alternativ e contro l system s abov e th e economi c impac t associate d wit hth e system

propose d a s BACT . A s a guid e i ndetermining whe n

1 8P.2 2

STAF F DRAF T Jun e 20 , 199 1 D O NO T CIT E O RQUOT E contro l cost s become excessive , alternativ e contro l system s can b e compare d i n term s o f certai ncos t effectivenes s ratio s suc ha s incrementa l cos t pe r uni t o f pollutio nremoved
. Th e analysi s o f energ yimpact s woul d b e don e i n a simila r manner . Th e environmenta l componen t o f th e analysi s woul d evaluat e th e ne t environmenta l impac t associate d wit heac halternativ e system . Bot hbeneficia l impact s (e.g
. reduce d emission s attribute d t o a contro l system ) an

d advers e impact s (creationo r exacerbatio n o f anothe r pollutio n problemthroughus e o f a contro l system ) shoul d b e quantified
. Th e incrementa l differenc e i n environmenta l impact s relativ e t o th e propose d systemwoul d the nb e evaluate d fo r an ymeaningfu l differenc e betwee nth e environmenta l impact s o f th e propose d systeman d th e othe r alternatives
. Th e analysi s shoul d includ e a complet e explanatio no f th e procedure s use d t o asses s th e economic , environmental , an d energ yimpact s an

d an y supporting data
. Th e EPAi s todaysoliciting commen t o nth e propose d chang e t o th e BAC T definitio n fo r th e purpos e o f clarifying an d delineating th e regulatorystandar d b ywhic hth e adequac yo f a BAC T determinatio n shoul d b e judged
. A s note d above , EPAalread y recognize s tha t ther e ar e a variet yo f permissibl e methods , including th e top-dow n method , fo r determining BACT . Applicant s an d Stat e permitting authoritie s ar e fre e t o appl yth e cor e lega l criteri a withou t referenc e t o an yexclusiv e metho d i n making BAC T determination s tha t satisf yth e Clea nAi r Act . V . Clea nFuel s Th e definitio n o f BAC T i n§ 169(c ) o f th e Ac t i s change d b y § 403(d ) o f th e 199 0 Amendments
. T o maintai nconformit ywit hth e statutorydefinition , EPApropose s t o amen d th e regulatory definitio n o f BAC T a t 4 0 CFR52.21(b)(12 ) an d 51.166(b)(12 ) b

y inserting "clean fuels " afte r "including fue l cleaning, " an d b y adding th e following a t th e en d thereof : "Emission s fro man y sourc e utilizing clea n fuels , o r an yothe r means , t o compl ywit h 1 9P.2 3

STAF F DRAF T Jun e 20 , 199 1 D O NO T CIT E O RQUOT E thi s paragraphshal l no t b e allowe d t o increas e abov e level s tha t woul d hav e bee n require d unde r thi s paragrapha s i t existe d prio r t o enactmen t o f th e Ac t Amendment s o f 1990. "

2 0P.2 4

••4

STAF F DRAF T Jun e 20 , 199 1 D O NO T CIT E O RQUOT E Propose d chang e t o BAC T definitio n i n regulatorylanguag e a t

51.166(b)(12 ) and 52.21(b)(23 )

"Bes t Availabl e Contro l Technology " mean s anemission s limitatio n (including a visibl e emissio nstandard ) base d o nth e maximu mdegre e o f reductio n fo r eac hpollutan t subjec t t o regulatio n unde r th e Clea n Ai r Ac t whic hwoul d b e emitte d from an ypropose d majo r stationarysourc e o r majo r modificatio nwhic h th e Administrator, 7 o n a case-by-cas e basis , taking int o accoun t energy , environmental , an d economi c impact s an d othe r costs , determine s i s achievabl e fo r suc hsourc e o r modificatio n through applicatio n o f productio nprocesse s o r availabl e methods , systems , an

d techniques , including fue l cleaning , clean fuels , o r treatmen t o r innovativ e fue l combustio ntechnique s fo r contro l o f suc hpollutant
. Tw o criteri a mus t b e satisfie d i nan yBAC T analysis : 1 1 th e determinatio n mus t conside r a representativ e grou p o f availabl e contro l system s fo r th e source , including th e mos t stringen t alternativ e available , an d 2 1 selectio n o f a particula r contro l systema s BAC T mus t b e justifie d i nterm s o f th e statutorycriteri a an d supporte d b

yth e record , an

d mus t explai n th e basi s fo r th e rejectio n o f th e othe r candidat e systems . I n n o even t shal l applicatio n o f BAC T resul t i n emission s o f an

ypollutan t whic hwoul d excee d th e emission s allowe d b

yan yapplicabl e standar d unde r 4 0 CFRPart s 6 0 an d 61
. I f th e Administrato r determine s tha t technologica l o r economi c limitation s on th e applicatio n o f measuremen t methodolog yt o a particula r emission s uni t woul d mak e th e impositio n o f an emissio n standard infeasible , a design , equipment , wor k practice , operationa l standard , o r combinatio n thereof , mayb e prescribe d instead t o satisf yth e requiremen t fo r the applicatio n o f bes t

7 Th e ter

m"reviewing authority " wil l b e use d fo r definitio n o f BAC T a t 51.166(b)(12 ) 2 1P.2 5

STAF F DRAF T Jun e 20 , 199 1 D O NO T CIT E O RQUOT E availabl e contro l technology
. Suc hstandard shall , t o th e degre e possible , se t fort hth e emission s reductio n achievabl e b y implementatio n o f suc hdesign , equipment , wor k practic e o r operation , an

d shal l provid e fo r complianc e b ymean s whic h achiev e equivalen t results
. Emission s fro man ysourc e utilizing clea n fuels , o r an

yothe r means , t o compl ywit hthi s paragraph shal l no t b e allowe d t o increas e abov e level s tha t woul d hav e bee n require d unde r thi s paragrapha s i t existe d prio r t o enactmen t o f th e Clea n Ai r Ac t Amendment s 1990
.

2 2