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OAR Box 1790 

Prepped by Keeia Richards 

Document Number: 

212) ll-F-1 

Docket Number: 

A-90-37 

Printed 10/31/2008 12:43:16 PM Sheet 212 of 250 
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UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

Office of Air Quality Planning and Standards 

Research Triangle Park, North Carolina 2771! 

VPS*? 

APR - 4 \zz*\\ Jf-f't 

Mr. James B. MacRae, Jr. 

Acting Administrator 

Office of Management and Budget 

New Executive Office Building 

Room 3236 

Washington, D.C. 20503 

Dear Mr. MacRae: 

At the March 7, 1991 meeting on the Wisconsin Electric Power 

Company (WEPCO) Interpretative Rule, the content and timing of a 

notice and comment rulemaking on best available control 

technology was discussed. It was agreed that the Environmental 

Protection Agency (EPA) was to prepare for review an outline of 

such a rulemaking. In response, my staff have prepared the 

enclosed draft. 

: , Please note that this draft material has not be,..3> reviewed 

by EPA's senior management. 

Enclof-c.. 

•c: R. Grady 

R i-'cnmalens;: 

A' ii' 

D. GioXons 

B. Gray 

r' TC Z 

I. r -nt.r 

T. G<- m • 

T C inbpecnt. 

J. Cher rear 

i . ;Imsted 

D. \ir>tt 

, , • r • rr ;• ri: r> '- ^ 

?r

-' zJU^jUT'Llfi. 

Liu, 'JAN 2 5 IT35 l!l 

EBW.ri r:cc;nr 
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STAFF DRAFT 

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AGENCY: ENVIRONMENTAL PROTECTION AGENCY (EPA) 

ACTION: PROPOSED RULE 

SUMMARY: To improve the effectiveness of the prevention of 

significant air quality deterioration program required by 

Title I, Part C of the Clean Air Act (Act), EPA proposes today to 

amend its rules to clarify the regulatory definition of best 

available control technology (BACT) by adding language that 

elucidates the legal requirements for a BACT analysis. The new 

language specifies that a BACT analysis must contain the 

following two core requirements: 

1) the available control systems for the <?curce must be 

considered in the determination, including ".hof.c '. ~ -.rovJ.*. the 

maximum degree oi emissions tedvc an/ 

2) Selection ~>f a control .• 

of er ' ..ons rpduction nus* >t. . . ._ 

rationale in —rmr of th atat

 ,r" r 

tir-- j ^ord, for ^ jCctinq th- <_ -:v--: 

. . . ..- uc»gree of confc. 

In d'*' •'tion, EPA prcpos* . tc 8'»

 v 

to e__ec; the -hange mac" •• '*y & 

.-unendments of ±^-,<J r X s--:atu-' . .. _. 

Zhe _;PA is .sitin g ' ,1 ; 

t o th e i?;.'uiatory -'fin___or. of 

DATES -oiruutsnts n. y be subi..^.utfc, 

or befor e

 r30 days irom am- of 
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STAFF DRAFT 

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ADDRESSES: Comments on this proposal should be sent to: 

FOR FURTHER INFORMATION CONTACT: 

SUPPLEMENTARY INFORMATION 

I. Background 

Major stationary sources and major modifications are subject 

to the prevention of significant deterioration (PSD) review 

requirements of the Act. A covered facility may not be 

constructed without a permit that meets the requirements of § 165 

of the Act. The current PSD program is represent by two sets of 

regulations. The first set of regulations, 40 CFR 51.166, 

specifies the minimum requirements that a PSD air duality permit 

program under Part C of the Act • Tst contr ,.i in c>'-.:.' t."- cbtr.ii' 

approval by EPA as a revision t. 

(SIP). The second set, 4. CFR 5 

permit program, which currently 

States that have not submitted .. 

requirements of 40 CFR 51.166. -•g: ~. .••-;..-th'XcK. • .• .. -ts£ 

are implementing their own PSD "*• Ah--": h... r..-.;-r> i .'•'.:••' >• 

.EPA under 40 CFR 51.166. .The 4-' :"."." . • d. t.rv- ' -•' -J' 

remaining Staces, most of which .'.•..-• .<• c-... ~A V."1 ''.: * . 

to implement the Federal PSD pr .-\ rr, '•-.. • -.TV! X 

requirements,, the facility must •'.;•;. ' . • 

40 CFR 52.21(j) (Federal rev/ula- x -XX 

(regulations netting forth the . .X.-

impie3aentation pltn (SJ'-) appv'0\ • . iX •»......' t v 

Sta ' :t , c;.le)Tif..7J . 

2 1 , .... • .*•.-. 'ii.'... 3- ," 

"li e • 3;,i .•>:.:-*• " i 

• ii • , , 'Z-'p:T 7 ' <<? • ., .'" 

-\q. ~.AC.I -t h •' .(.A:, 

'Xi • 

1 7

 •:•: 

•i ' i? 
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40 CFR Part 52, Subpart A - Subpart FFF (various SIP 

requirements)].1 

Emissions limitations reflecting the application of BACT 

must be set forth in the PSD permit § 165(a)(1). To obtain a PSD 

permit, an applicant must, among other requirements, conduct an 

analysis in accordance with EPA regulations to ensure the 

application of the BACT to each new or modified emissions unit 

[Act § 165(a)(2, 4)]. The required analysis must address "the 

degree of continuous emissions reduction which could be achieved 

by such facility," § 165(e)(3)(B) [see, e.g., 

40 CFR 52.21(n)(l)(3)]. 

The term "best available control technology" is defined in 

the Act as: 

an emissions limitation based on t' 

reduction of each pollutant -^ Ljeu 

the Clean Air Act emitced f- •' or. 

any major emitting facxlit' 

authority, on a case-bv-c" 

energy, environmental, an'. 

costs, determines is 2hie .* . 

through application o. pro- <y 

available methodt . sy.v rremF ^ • 

fuel cleaning, ciaan • elffuel COILbust ion techi. ;uei_ 

polluta;.-. in no ••vexX fX 

aval] at contro_ _ec, oio 

any pol itants whirX , •11 e 

'-v any applicable st. ard 

.:tion ""11 or

 7412 ,.. th 

source "rtilizii clean cu 

oomplv ' :.th this parage aj: 

increass- ^bove levels *Ta' 

"ind T '.: paragraph as it 

of .~.ie Cist,..: Air Act Amenc 

maximum oxroqulf 

:7.su:. 

;A7 'T-ii.% • 

ree of 

•-- une1 ^ 

--, 

l-t t1Under the riean Air Act Am-" 

circumstances BACT is also a reunder Part D cf the Act. 
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[The CAA § 169(3), as amended by § 403(d) of the Clean Air Acts 

Amendments of 1990]. 

During each BACT analysis, which is done on a case-by-case 

basis, the reviewing authority evaluates the energy, 

environmental, and economic impacts and other costs associated 

with each available control technology. The reviewing authority 

then specifies an emissions limitation for the source that 

reflects the maximum degree of reduction achievable for each 

pollutant regulated under the Act, considering the factors 

enumerated in the definition quoted above. In no event may a 

technology be selected that would not meet any applicable 

standard of performance under 40 CFR Parts 60 (new source 

performance standards) or 61 (national emission standards for 

hazardous air pollutants). 

In addition, if the reviewing authority determines that: 

there is no economically-reasonable or te-"Knologically-fea,,.X 

way to accurately measure the emis^.'^'is, ar:2 hence to imp°i. • 

enforceable emissions standard ii ; v require the souro . < ,-e 

design, alternative equipment, wei.;. . &-.Tic: .. or oper; 'Ai.oi A' 

standards to reduce emissions r '•'• t.^e >c ...•„. tc the ;•'.• ..•..'.<. 

extent [40 CFR 52 .21(b) (12) ; 4G C X '...'. . (^)(12>;X 

. In January 1979, EPA issu< - *x. XUanca for Dete*-^ inX.tr 

under PSD," and in October 198f ;... v A < ' J;.Z Wor}' . ,.: ' 

(EPA 450/2-80-081). These docu.^e' ..-. f.cuX-i; • m apr- • 

(." 

2F-r exanple, if a coal st -;... . :•:!( < -•. -"..a.. ••'"• 

atmosphere, it would make ..itt" ' iii-.s:. A- • •• "•<:..•-•.* •/.<-. .•^.'.'•.•i,"^ 

standard, since measuring the . -TAAI- r- '• :..- . ?X i/.. oi «' 

pile may be nearly impossible, A m^ 2 &-,?<„ ...'.re.ict >..j. • w.'-

controlling emissions is, for eT«-;.VL- rv^..Z.:- » . - tbe- "-..-7-7-z tithe coal pile periodically or t •'-..X. i!/ "•'•:...„?. 'Jof operational standard or work j ;.Ji.' "i ••oiiid '- :-,X.. 

an emissions limitation for the pu r. jx.". _• of ihe <'.••'' reqi'X..•.'•.• 

i.' 
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BACT analysis in which the applicant was to propose a base case 

as BACT, present more stringent control alternatives, and defend' 

its BACT selection "demonstrating that each alternative control 

system... would cause unreasonable adverse energy, environmental, 

or economic impacts" (see "Guidance for Determining BACT under 

PSD," January 4, 1979, at 5-6). 

In June 1986, EPA established a New Source Review Task Force 

to address growing concerns about the effectiveness of the new 

source review (NSR) programs in meeting the statutory 

requirements, and to recommend actions to improve EPA's exercise 

of its oversight and enforcement responsibilities in implementing 

the NSR program. The Task Force found, based on a comprehensive 

review of numerous PSD permits issued during the previous several 

years, that PSD applicants and States frequently were conducting 

inadequate BACT determinations using the method outlined in the 

197.9 guidance and the 1980 worksh^'' manual. In nuinu. ous 

instances, applicants would propose a^ *• ic:-'- .' X t./^ioi. at <• 

near an applicable new source pe "TU ..ct T-.:- : ">S) ur-.di 

§ ill of the Act as the base cas anc1 or ..xJ.-yj ••'•• 

consideration of the more stringeuv. r— •<• •' 

settling on the proposed level in. ."•' . v.- . .<, 

accept these determinations with Xu >rx 'bnt 

analysis, thereby failing to ful *'h •>-*• s- ->-;«-• - • 

the Act. The Task Force poi :ed . .-T -J.I - . .a, v:c 

problem ot inadeguate BACT a alys 'Cv. • 

4"iproviag implementation of he « . Ji i " . .. 

practice as well as in th^or •, t -a... ;• 

be .. ...filled. The other op- .on wr- A 

approach to the BACT analyses ir :•-->. tinternal dynamics would, in prac .. ..u , ac 

implementation of the BACT requir' • =nt.- . . ••J.v ir"< . 
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Source Review Task Force Report," Final Draft, December 1986, at 

25-28]. 

In the meantime, in an adjudicative decision on appeal of a 

PSD permit for a municipal waste combustor (MWC), the 

Administrator held that a PSD applicant has the "burden of 

demonstrating that significant technical defects, or substantial 

local economic, energy, or environmental factors or other costs 

warrant a control technology less efficient than [the most 

stringent technology available]." Honolulu Resource Recovery 

Facility ("H-Power"), PSD Appeal No. 86-8, at 7 (Remand Order, 

June 22, 1987). Shortly thereafter, EPA issued guidance calling 

for application of the H-Power holding to all BACT determinations 

for MWC s ["Operational Guidance on Control Technology for New 

and Modified Municipal Waste Combustors," June 26, 1987]. 

In light of these events, EPA dec ^d that as a i.i. 

Agency policy it would adopt what ha: p.e to be fcnowr !"•>]» 

down" BACT method for all categorie, o SD sourctj. I*. -

the top-down process provides that c _. .-Tillable cont. • 

technologies be ranked in descending < OT cnnt'• 

effectiveness. The PSD applicant iX • "inei f 

stringent—or "top"—alternative. ' ' _•„ mat..'"• .

; 

established as BACT unless the. apt>l:'.-: 'le--.or... :i ;• 

permitting authority in its informfc . -.-A. <_•. .

 : 

technical considerations, or energy. .re.•.;,.-. X X 

impacts or other costs, justify a • • L<.n T 

stringent technology is not ''ach; '•;•• ' 

.35&_ stringent technology is eliiM.i:.- X. >.;... . x ^ 

next most stringent alternative j.t :re-'' arX ••.-"* 

In a December 1, 1987 memor "' • Hear • • ••• i 

its RegionaJ offices to use a to- -cx>. Xsoi . A ' r < • 
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determinations, and to strongly encourage state and local PSD 

permitting authorities to do so as well [see December 1, 1987 

memorandum from Craig Potter, Assistant Administrator for Air and 

Radiation, entitled "Improving New Source Review"]. The 

memorandum further directed Regional Offices to conduct timely 

reviews of PSD applications, and to comment adversely on proposed 

PSD permits that failed to adequately consider the more stringent 

control options, as would be required as a matter of course in 

any acceptable method of determining BACT. If final State and 

local permits still failed to reflect adequate consideration of 

the relevant BACT factors, the Regions were to consider such 

permits deficient; and were to consider appropriate enforcement 

action under §§ 113 and 167 (in the case of State-issued permits) 

or appeals to the Administrator under 40 CFR 124.19 (in the case 

of Federal permits) to remedy such deficiencies. An additional 

point related to the top-down process is that it should, in 

practice, lessen administrative burd:~-n« in the cone 

determinations because it doe.* ; 

control alternatives that are mort 

other base case, as would be reqiX 

In the spring of . °90, EPA made . 

documer , entitled '""cp-down E. 

Guidance Document. ueta .ling t if 

In calling for use of the \.o 

change the existing T regulat""-•' 

leauirements for any source. 1.. 

statute, Ji. regulations and '. ' 

to'.-down approach dimply c..ari3._< 

out the existing statutory and ~ 

to assure that they would be fv_. 

in the condi 

a full 

••l<72T.t tha i 

r.a thi. • 1 

e t o 'i 3c ' 

'^le Ccn.'.ri'.. 

3 AC. »-•-' 

m p ? 06.C;., 

• »•'•' • 

; 

:-

, 

$ • 

„ 

of BAC 

J.S o f 

-

• - . . - . 

%-. 
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m,. . • ... . , ..-• . •«#•:,. ' ; •:. 

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On March 29, 1989 (supplemented on May 3 and 10, 1989) , the 

American Paper Institute and the National Forest Products 

Association (collectively "API") petitioned EPA to rescind the 

top-down policy and initiate a rulemaking on BACT determinations. 

T he EPA denied this request on May 12 , 1989 (supplemented on 

June 13, 1989) , explaining that the top-down approach was not at 

variance with, nor a revision of, the PSD regulations, and that 

no rulemaking was required. Subsequently, API filed suit in the 

D.C. Circuit and in the U.S. District Court for D.C. API v. 

Reillv. D.C. Cir. No. 89-1428 (filed 7/10/89); 

A PI v. Reilly. D.D.C. Cir. No. 89-2030 (filed 7/18/89). A 

consortium of utilities also filed a petition for review of EPA's 

actions, Alabama Power Co. v. EPA. D.C. Cir. No. 89-1429 (filed 

7/11/89), and the case was consolidated with the API case. The 

same consortium filed an administrative petition with EPA on 

February 1, 1990. Finally, API also challenged tne .1990 EP/. 

draft guidance document on top-down BACT, API v. Rejllv D.L>. 

N o. 90-1364 (filed. 7/13/90).. Settlement negotiations ~ rrently 

are. underway regarding these cas .. The EPh has. decided i•• c 

matter of policy to conduct this ivr^p^ped rulen.^-int; to 

facilitate greater public partic ]~>:n..:i.c • . . ' / isr.-iing -;••••-:•• X v 

notwithstanding EPA's position that it 1 T •.;*:>•.. leg*..'. / i ^AAA A t-o 

do so. 

I I. Legal Requirement -• r, TT" • ...xysis" • 

In adopting the PSD prograi , . Conr-^--;- . .'T'v-.aizc-:.. • 3: 

importance of thorough and rubli-

 ;?

 Z'\ <-' r ..•. •O'i'ior, 

by stating that une of the purpc • --. f&j AA CL^A\T • th#/: 

decision to permit increased aii •••-zr v.ticj : >,. JAA i.v. ev*. 'hx :.;•;' "••.•*. • 

this section applies is mad. onl\ rx. i.-.. < -n- .,, . ''aluav,. A> .T •;• Z.\ 

the consequences of such a decision and' ;•.. J : ..'.^v'- • 

opportunities for informed public parti ri.pavx--02 %}:• '-A 

'AZ •• , •!'.•. 

JC?X t,. :... 
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making process. As noted above, § 165 specifies, and EPA 

regulations reflect, the requirement to conduct a BACT analysis. 

The statutory emphasis on procedural rigor is accompanied by 

expressions of congressional intent that States have wide 

discretion in setting final emissions limits reflecting BACT. 

The legislative history on BACT makes clear that Congress meant 

the State to make the final substantive decision on the 

appropriate level of technology. The key passages of the Senate 

report show that the State has broad flexibility to exercise its 

judgment in implementing BACT. The report states: 

The decision regarding the actual implementation 

of best available control technology is a key one, and 

the committee places this responsibility with the 

State, to be determined in a case-by-case judgement. 

It is to be recognized that the phrase has broad 

£2 exibility in how it should and can Le interpre1-

depending on site. 

In making this key de . ' o- < . .& •" ' X *• ~ 

be used the State is to taK 

env4 • onmenta"* , en ecommi 

th-* application oi best aval. 

T;.i weight a igned "ucb - --\c_v 

,

v-y the ~ate. Such a ex._ . 

adoption of 'mprov ir 

widespread far iuoi. j.& _T 

uniform Federal tar___u. ( 

[S Rep. No. 95-? 17, 95th oor.g., : 

added).] 

r 

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• "• ^Wto 

D^C" ' 

_tr_ 

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STAFF DRAFT 

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At the same time, the Senate Report places limits on State 

discretion in two respects. First, it is clear that Congress 

intended one of the advantages of State flexibility to be to 

speed up the adoption of advances in control technology.3 

Second, it is also clear that in adopting BACT, Congress intended 

PSD permitting authorities to exercise informed discretion to 

weigh energy, environmental, and economic impacts in determining 

BACT for a particular source. 

These statutory goals can be fulfilled by more than one 

method of determining BACT. Regardless of the specific 

methodology used for determining BACT, be it top-down, the method 

embodied in the 1979 guidance, or otherwise, EPA has consistently 

interpreted the relevant Act provisions as embodying two core 

legal criteria that must be satisfied in any BACT analysis. 

First, the permit applicant must consider available control 

technologies, i.e., those that "provide the maximum ue^ree of 

emissions reduction." Whether a technology is "available" 'V 

purposes of BACT is a practical, ff~tua3 detein ' ••<*tio.n, 

conventional notions of whether the technology car '^e puv 

use. See' 1 ^nnsauken County. Nev* /' :rsy K.....:^..,"ce Recovi "7 

Facility. PSD Appeal No. 88-8 (Remand OrrV'r; Nov. 10 I! • • ••• • . 

Each type of available contrr" 

electrostatic precipitator, a dr^ f 

carbon absorber) or combination o: 

3[See ?lso statement of Sen.-"'-

(June 8, 1^77)]. This constructs 

in later PSD appeal <? ;cisioni3, [ 

. rsey Resource Recovery Facility 

Order, Nov. 10, ^ ^P)]. In these -

interpreted the BACT definition as 

. .. -lonst.- .e to the permitting aa. 

• ontrol technology "available" w.--

TAX 

:\j). . 

, ..re 

MUSK 

VArO y 

' • •' 

.'. (e.g. , c 

, a \vim. i-Cr. .. 

i Kv-'tems sxv 

•infoiced i 

• >.t'.' 'th e "T .iri . 

i'.A Ax - ..ct .. ' S'C;. 

• • • 

i 

. > 

' .-*»1, " 

LTt..;.-

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STAFF DRAFT 

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analyzed at the maximum level of control achievable for the 

control system or combination of control systems as it would be 

applied at the proposed facility in question. Major alternatives 

within a given type of control system should also be considered 

(e.g., electrostatic precipitators that can achieve 96%, 98%, and 

99.5% control efficiency, respectively). However, analyses of 

numerous minor variations in control systems or combinations 

thereof is not required. Second, any decision to require less 

than the maximum degree of emissions reduction must be justified 

by a reasoned analysis of "energy, environmental and economic 

impacts and other costs" contained in the record, and the 

permitting authority must exercise its informed judgment before 

accepting that justification. 

These two core criteria have been singled out in the 

administrative appeals decisions subsequent to the K-Power 

decision as being the essencial re, r

r

" •*.. f a BA'"" ana.' 

Th j n Union county Rer 'rce Recover _, ' X__y < ' " 

No. 90-i /28/90) at the Admin. •-...-v>r c.ted compX .;c withe two core critei .. in rtph-\d:: ••T, n. s. L>~ a 

resource recovery facility. = i'h< * on • r~-

two core criteria . A i-^noldi^q a .n....u.- oe1 x^i 

Mecklenburg Cogeneratic. "mitec . ^ „ .3k_s; •"" 

PSD Appeal No. 90-7 (12/? /9r ) ai ;:• . 

Althr ;gh £PA be]'°ves t uv 

regulatory definitions of BA' • • 

consideration or these tw u e .. C-T, 

ade<>uate EACT de*—>rminct:.c. uhe .... ' ' 2.72 f 

t

h

 .2.3 rement explicxt .jy ins " . X.;; 

definition of BACT th. - follow1 nu .n-• 

analysis: 
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7 XV .T " ; 

1) the available control systems for the source must be 

considered in the determination, including those that provide the 

maximum degree of emissions reduction, and 

2) Selection of a control system providing a lesser degree 

of emissions reduction must be justified by a rationale, 

documented in terms of the statutory criteria and supported by 

the record, for rejecting those control system(s) providing a 

greater degree of control. 

III. Purpose of the Proposed Change 

To date, the 1979 and top-down approach have only been 

considered as guidance by EPA in.conducting an appropriate BACT 

analysis based on the definition of BACT in the Act and in EPA's 

regulations. They have not established binding regulatory 

requirements. Such requirements ace contained in the Federal 

regulations and SIP's. Instead, EPA's 2&CT guidance- ^.>i ... T '.. .CYH'I 

to guide p vrmitting officials in •Xvse arpsr 3 „>je<3-. ... 

Federal PSD regulations at 40 CF! :'.;•:.:::>. 

Rather than specifying a pre- .««?; x-P?' '•" '• • • • • "•• 

analysis, an<; evaluating the adeu- X '•'•' - i"A'A\ •X.. .3' •" .-': 

against that approach, EPA is pro.> .-Sii ;. X;J>•;.•.. X- •.',.;• . • • o 

core legal requirements necessary -r . ..-;.. .27. '• 

Thus, adherence to a top-down a\ - :.'-c. .. z-vi 2 c A'KA 

reviewing new or revised State Pi? /••.< ... •y.

,

.i-. \ ?...-? -A • 

approval, the Agency will deem tl. •/, ' • bf- IT'•.. X 

provides for comj '"iance with the. -• • •• \ •-.-•.-. t: * 7 ' 

an adeguate BACT analysis. Like'-. •-• • <' 1 X J. ';; • I ist - >* •;• 7 - •; Zfz • 

and enforcement responsibilities, 7.-A '..,:•• v» I - .

 v' - uX *tu. 

policy of reviewing specific per ' «.'" iv' "-' r •>'•-•• >• '•- - * "*''• -"' i 

with the core criteria. So Ion; '-' "-...,• '.ire. ..X. 
STAFF DRAFT 

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procedural norms embodied in the core criteria and does not 

violate any objective standards that may apply (such as NSPS or 

SIP limits), EPA will consider a State's BACT analysis to be 

adequate and will not second-guess the State's substantive BACT 

decision. Conversely, permits containing BACT determinations 

that do not conform to the PSD requirements of the Act, EPA 

regulations, and applicable SIP's, as reflected in the core 

criteria, will be considered deficient by EPA. Instances of 

procedural irregularities pr arbitrary decisionmaking will remain 

grounds for enforcement action or permit appeals, as appropriate. 

The EPA is today soliciting comment on the proposed change 

to the BACT definition for the purpose of clarifying and 

delineating the regulatory standard by which the adequacy of a 

BACT determination should be judged. EPA continues to believe 

that the top-down method is an efficient and highly reliable 

method of conducting a BACT analys in conformity v.ith th~ 

statJtory BACT definition. Thereft '^n :h ; ^ .?.ic-. ..«• . .AC 

reviewing agencies are encourage ic • c>n\;.;...•.. 

the approach as described ir the ' '"•'« c 

the purpose jf permits issued und . . 

above/ however EPA acknowledges ••... r . . 

the v ily permissible methc^ of. c^r. ' .:.. . 

St; -'•> permitting authorities rem.'.. ••>•>. 

legal "iteria without reference . . <- mt . 

^•ACT determinations that satis fv 

IV. Jl .. . ' 

The definition of BACT in t. . , ... ... r... > 

§ 403 fd) of the 1990 Amendments X TT-' -t. . . > •' 

ty Tutory definition, EPA proposer x.- ........ -7 02 

definition of BACT at 4n C? 5?xx X' . ., 
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inserting "clean fuels" after "including fuel cleaning, and by 

adding the following at the end thereof: "Emissions from any 

source utilizing clean fuels, or any other means, to comply with 

this paragraph shall not be allowed to increase above levels that 

would have been required under this paragraph as it existed prior 

to enactment of the Act Amendments of 1990." 
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Proposed change to BACT definition in regulatory language at 

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

"Best Available Control Technology" means an emissions 

limitation (including a visible emission standard) based on the 

maximum degree of reduction for each pollutant subject to 

regulation under the Clean Air Act which would be emitted from 

any proposed major stationary source or major modification which 

the Administrator,4 on a case-by-case basis, taking into account 

energy, environmental, and economic impacts and other costs, 

determines is achievable for such source or modification through 

application of production processes or available methods, 

systems, and techniques, including fuel cleaning, clean fuels, or 

treatment or innovative fuel combustion techniques for control of 

such pollutant. Two criteria must be satisfied in anv BACT 

analysis: 11 the avaliable control systems for the source must 

be considered in the determination, including those t.i.at provide? 

the maximum degree of omissions rp

r< ction. and 21 se. •-•^'-"* XL-_.,'2'...' 

control system providim a lessej 21r.ee ' "missj/cjs T "'• 

must be justified by a ratis ale, <* .enteg ... -^

 r r 2" .-. 

statutory criteria and sup^, :___LxM: ie re^ -__£SJ -X •_ 1 

control syste^nfsl providing a gr "_/ -x __..,„ 

event shall application of \ \CT > i*v ,; 

pollutant whi. would exceec the

 v .n ; Oovec Y 

applicable standard unf ~ * CFT ..... ».' .e 

Administrator determine. *"h?,** te. 

limitations on the ap " '.cati jn o 

particular emissions unit would 

emission standard inft^siblr . a •• 

operational standard, or cc oina . . ••-.. .7?^ , ;- be pr<_ 

" OC 

neasv 

..... 

•-... . 

.a ; -.. 

epi-i.--.-o' 

-'SJ* . 

,.. c><1 — ' 

4The term "reviewing authori- ' ". b u e 

BACT at 51.166(b)(12) 
P.18 

STAFF DRAFT 

""' "DO" NOT C*ITE OR QUOTE 

instead to satisfy the requirement for the application of best 

available control technology. Such standard shall, to the degree 

possible, set forth the emissions reduction achievable by 

implementation of such design, equipment, work practice or 

operation, and shall provide for compliance by means which 

achieve equivalent results. Emissions from any source utilizing 

clean fuels, or anv other means, to complv with this paragraph 

shall not be allowed to increase above levels that would have 

been required under this paragraph as it existed prior to 

enactment of the Clean Air Act Amendments 1990. 
P.19 

STAFF DRAFT 

DO NOT CITE OR QUOTE 

also clear that in adopting BACT, Congress intended PSD permitting 

authorities to exercise informed discretion to weigh energy, 

environmental, and economic impacts in determining BACT for a 

particular source. 

These statutory goals can be fulfilled by more than one 

method of determining BACT. Regardless of the specific 

methodology used for determining BACT, be it top-down, the method 

embodied in the 1979 guidance, or otherwise, EPA has consistently 

interpreted the relevant Act provisions as embodying two core 

legal criteria that must be satisfied in any BACT analysis. 

First, the permit applicant must consider available control 

technologies, i.e., those that "provide the maximum degree of 

emissions reduction."4 Second, any decision to require less than 

the maximum degree of emissions reduction must be justified by a 

Order, Nov. 10, 1988)]. In these cases, the Administrator 

interpreted the BACT-definition as recuiring the P$0 r^olicar . t . 

demonstrate to the permitting author - <' -• "-hy the i,ot strings , 

control technology "available" was nov chievable." 

* Whether a technology ie ".• .vailab . 

a practical, factual determination, »"'X\ 

whether th technology can be put iv.U, x2' 

New Jersy Resource Recovery FacXUty. ? . 

Order, Nov. 10, 1988) at 8. 

Each type of available control &i -

electrostatic precipitator, a dry sc MX:, 

carbon absorber) or combination oX cor'., ' 

analyzed at the maximum level o

r con^rr;. . 

system or combination of control cy-- Xv.«' 

the proposed facility in questio- Ha>... 

given type of control system sh ,-,•-._ aXv. 

electrostatic precipitators th?-t • •\r; XJ 

control efficiency, respective^

 f' 

minor variations in control syst> 

required. 

.foi purp*"v' • 

convG-.tioTu. 

rae Penn*?- • 

•A, a \ ,.• 

! RV sterna 

;a,tevabX; 

cons... 

• 96% , 

,'tVJ 

P.AC. • 

i • 

CQyyn; * 

J •' i» .r, 

•*v, . 

nf- "•• • 

oo' *.'. 

•c 

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Cl .4