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OAR Box 1787 

Prepped by Ollie Stewart 

Document Number: 

9) ll-A-9 

Docket Number: 

A-90-37 

Printed 11/4/2008 10:22:18 AM Sheet 9 of 147 
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LS DRAFT 

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ontrol 

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Guidance 

Document 

EPA Region 9 
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GUIDELINES FOR DETERMINING 

BEST AVAILABLE CONTROL TECHNOLOGY (BACT) 

EPA REGION 9 

New Source Section 

April, 1987 
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•*.x ' r 

Preface 

This guideline document was prepared by the staff of EPA 

Region 9 using their collective experience in implementing the 

New Source Review and Prevention of Significant Deterioration 

requirements of the Clean Air Act Amendments of 1977. The 

document is intended to be used as a guide for determining 

emission control technology for new or modified sources subject 

to-the PSD regulations. 

The determination of BACT involves the entire community 

affected by air pollution and its control, and it is this 

community that must take responsibility for its correct 

implementation. I am grateful to my staff for preparing this 

document; to the state and local air pollution control agencies 

in Region 9 for their support; and to industry for their 

cooperation in meeting these requirements. 

Wayne A. Blackard, Chief 

New Source Section 

The EPA Region 9 staff responsible for preparing 

this report are members of the New Source Section 

and all are Environmental Engineers. 

AUTHORS 

Matt Haber 

Robert Baker 

James Hanson 
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TABLE OF CONTENTS 

I. INTRODUCTION 

II. PURPOSE 

III. DEFINITIONS 

IV. APPLICABILITY 

V. IDENTIFICATION OF CONTROL ALTERNATIVES 

- Categories of Control Alternatives 

- Sources of Information on Control Alternatives 

- Requiring the Use of Clean Processes, Fuels and 

Solvents that are Inherently Lower Polluting 

VI. EFFECTIVENESS RANKING OF CONTROL ALTERNATIVES 

VII. IMPACT ANALYSIS OF CONTROL ALTERNATIVES 

VIII. COMPARISON WITH OTHER PERMITTED FACILITIES APPLYING A 

MORE STRINGENT BACT 

IX. SELECTION AND JUSTIFICATION OF A CONTROL ALTERNATIVE 

AS BEST AVAILABLE CONTROL TECHNOLOGY 

X. AGENCY REVIEW OF THE NOMINATED CONTROL ALTERNATIVES 

XI. CONSTRUCTION PERMIT REQUIREMENTS 

- Permits Must be Enforceable as a Practical Matter 

- Permit Conditions Must be Federally Enforceable 

- Public Participation 

- Phased/Delayed Construction 

XII. BACT FLOWSHEET 

XIII. CONCLUSION AND SUMMARY 

XIV. APPENDIX 

APPENDIX A - BACT Flowsheet 

APPENDIX B - BACT Analysis 

APPENDIX C - Remand of Appeal No.85-2 

APPENDIX D - Order Denying Review of Appeal No. 85-2 

APPENDIX E - Permit Requirements 
P.6 

GUIDELINES FOR DETERMINING BEST AVAILABLE 

CONTROL TECHNOLOGY (BACT) 

INTRODUCTION 

Congress, in passing the Clean Air Act amendments of 

1977, established the Prevention of Significant Deterioration 

(PSD) program partly to prevent the flight of industry from 

the severely polluted areas of the county where control 

technology requirements are very stringent to clean areas 

without control technology requirements. Under the PSD 

program, Best Available Control Technology (BACT) is required, 

and is determined on a case-by-case basis rather than automatically applying an applicable New Source Performance 

Standard (NSPS). 

II. PURPOSE 

The purpose of this document is to provide technical 

assistance and guidance to those who must determine BACT 

for the proposed construction or modification of new sources 

and facilities. The guidelines are directed solely to the 

analysis of alternative technologies for BACT and assumes 

that all other review requirements are accomplished. 

The emphasis of this guideline is on the types of data 

which should be required in a preconstruction permit application and how the data should be used in order to determine 

BACT. The guideline addressess the question of whether the 

emission control system proposed in the permit application 

represents BACT or whether a more stringent level of emission 

control is appropriate considering available technology and 

economic, energy, and environmental factors. 

The Act places the responsibility of proposing BACT with 

the applicant and the responsibility of determining BACT with 

the permitting agency. This approach places on the source 

the additional responsibility for presenting and defending 

its proposal. 

BACT determinations should be consistent from area to 

area. In the context of a case-by-case BACT, consistency 

does not necessarily mean that a new facility in one area 

will have an identical emission limit as the same type of 

facility in another area. Consistency means that a consistent approach is used in determining BACT and that the impacts 

of alternative emission control systems are measured by the 

same set of parameters. 
P.7 

III. DEFINITIONS 

In an attempt to provide some clarity to the preparers 

and reviewers of PSD*permit applications Region 9 has 

utilized the following definitions and general policies 

in our BACT determinations. Detailed information can be 

obtained from the Prevention of Significant Deterioration 

Workshop Manual, October 1980. 

°Lowest Achievable Emission Rate (LAER) 

LAER determinations are required for all nonattainment 

NSR permits and represent the more stringent of any 

emission limit either 

-required in a SIP or 

-achieved in practice 

for any class or category of source. Note that, in California many air pollution control agencies require 

BACT in nonattainment areas? however, those agencys' 

BACT definitions are essentially the same as EPA's LAER. 

In Region 9, BACT for PSD frequently equates to this 

level of control. 

"Best Available Control Technology (BACT) 

The Clean Air Act defines BACT as "...an emission 

limitation based on the maximum degree of reduction 

of each pollutant subject to regulation under this Act 

emitted from or which results from any major emitting 

facility, which the permitting authority, on a caseby-case basis, taking into account energy, environmental, 

and economic impacts and other costs, determines is ' 

achievable for such facility through application of production processes and available methods, systems, and techniques, including fuel cleaning or treatment or innovative 

fuel combustion techniques for control of each such pollutant". No BACT determination may be less stringent than 

the applicable NSPS, NESHAPS, or SIP limits. 

"New Source Performance Standards (NSPS) 

The limits dervived under NSPS are emissions limitations, 

or percentage reductions "achievable through application 

of the best technological system of continuous emissions 

reduction which (taking into consideration costs, 

health, environmental and energy impacts) has been 

adequately demonstrated for...stationary sources..." 

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"Prevention of Significant Deterioration (PSD) 

The PSD permit program addresses the permitting of 

industrial sources in attainment areas. The primary 

purposes of the program are: (1) to protect the public 

health and welfare from any adverse effect which might 

occur even at air pollution levels lower than the NAAQS; 

(2) to preserve, protect and enhance the air quality 

in areas of special recreational, scenic, or historical 

value; (3) to ensure that economic growth will 

occur in harmony with the preservation of existing 

clean air resources to prevent the development of any 

new nonattainment problems; and (4) to ensure that the 

best controls are installed on all large, new or modified sources. 

"Non-Attainment Area New Source Review (NAA) 

The NAA permit program addresses the permitting of 

industrial sources in nonattainment areas. The primary 

purposes of this program are to insure that: (1) emissions 

of a proposed source are either offset sufficiently 

such that reasonable further progress toward attainment 

is achieved or, that emissions have been accomodated 

in a federally-approved growth allowance; (2) the source 

meet the lowest achievable emission rate; and (3) the 

owner or operator of the proposed source has demonstrated 

that all major stationary sources owned or operated by 

such person in such State are in compliance with the Act. 

"New Source Review (NSR) 

New Source review is the combined permit program for 

the review of sources locating in attainment or nonattainment areas. Because attainment designation are 

made on a pollutant-specific basis, an individual 

source undergoing new source review may be subject to 

both attainment (PSD) and nonattainment (NAA) permit 

requirements. 

"Major Stationary Source 

A major stationary source under PSD is defined as any 

of 28 stationary source categories which emits, or has 

the potential to emit, 100 tons per year or more of 

any pollutant regulated under the Act or, notwithstanding 

the stationary source category, any stationary source 

which emits, or has the potential to emit, 250 tons 

per year or more of any pollutant regulated under the 

Act. 

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"Minor Source 

A minor source at the time of application is not subject 

to PSD. A modification at an existing minor source 

may trigger a PSD review of the source. (See Section 

IV, Applicability). Minor source growth in an attainment 

area must be accounted for during the review of major 

sources. 

'Major Modification 

A major modification means any physical change in or 

change in the method of operation of a major stationary 

source that would result in a significant net emissions 

increase of any pollutant subject to regulation under 

the Act. 

"Significance Level 

Significance levels are defined in reference to a net 

emissions increase at a major stationary source for 

purposes of determining whether an increase in emissions 

constitutes a major modification. Significance levels 

are specified for 15 pollutants regulated under the 

Act. For other pollutants regulated under the Act, any 

increase in emissions of the regulated pollutant is 

considered significant. 

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P.10 

IV. APPLICABILITY 

Applicabilty of the BACT requirement, like all other 

aspects of a PSD review, is on a pollutant specific basis. 

Once a pollutant has become subject to PSD review, the BACT 

requirement will apply. While there are certain exemptions 

contained within the PSD regulations for other parts of the 

review (for example, temporary sources are afforded exemptions 

from monitoring and other requirements), there are no exemptions 

from the BACT requirement. The BACT requirement could thus be 

viewed as the cornerstone of the PSD program. 

In brief1, source applicability for BACT (and PSD review) 

is as follows: 

"For a new major source or an existing minor source: 

- When potential emissions are at least 100 tons/yr 

for the 28 listed source categories (see 40 CFR 52.21 

(b)(l)(i)(a) for a listing of the 28 source categories) 

or 250 tons/yr for all other source categories, the 

source is then subject to PSD review. BACT then applies 

to any unit that emits any amount of the subject pollutant. 

"For existing major sources, applicability occurs in one of 

three ways: 

- When contemporaneous^ emissions increases exceed the 

promulgated significance levels (these values are found at 

40 CFR 52.21 (b)(23)(i)), BACT then applies to any_ unit 

that shows any increase in emissions of the subject 

pollutant. 

- When any emissions increase of a regulated pollutant for 

which a significance level has not been promulgated occurs 

at an existing major source. Currently, benzene, arsenic, 

and radionuclides fall into this category. 

- When emissions from a source located within 10 km of a 

Class I area would cause an air quality impact greater 

than 1 ug/m3 on that Class I area. 

*A thorough discussion of the applicability requirements may 

be found in the 1980 PSD Workshop Manual. 

^Contemporaneous emissions are all creditable increases and 

decreases occurring from five years prior to the commencement 

of construction, up to the start of operation. 

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P.11 

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Once a source has been determined to be a major source on 

the basis of one pollutant exceeding the 100 or 250 TPY threshold, all other pollutants are reviewed against the significant 

emission rates in order to determine review applicability. For 

new major sources, each emission point with any emission rate 

of the applicable pollutant is subject to the BACT requirement. 

For major modifications, each emission point at which an increase 

in the applicable pollutant occurs is subject to BACT. 

BACT must be applied to all processes and operations which 

could emit the PSD regulated pollutant. These include stack 

emissions, fugitive emissions and emissions from equipment 

which may not be operating continuously. 

The manner in which the emissions limits and controls 

should be determined will be discussed in detail later. However, it may be noted here that the type of use to which equipment will be put may ultimately influence the BACT determination. 

For example, for equipment that is used infrequently, controls 

that have high operating cost but lower capital cost may be 

more appropriate. 

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V. IDENTIFICATION OF CONTROL ALTERNATIVES 

Of primary importance in making a BACT determination 

is the identification of control alternatives for the 

source subject to BACT. At this step of the BACT review 

process, no technically feasible alternative should be 

ruled out as a possible BACT candidate. The identification 

of control alternatives should not be limited to a review 

of existing controls for the source category in question. 

The review must be broad enough to take into account 

controls applied to similar source categories and even to 

consider innovative control technology where energy, 

environmental, or economic impacts so warrant. Finally, 

the identification of alternatives should include the 

control alternatives representative of LAER for the 

source or category of source. While BACT and LAER differ 

considerably in their definitions, in practice they are 

often the same. As will be discussed in a later section, 

the selection and justification of a control alternative 

as BACT should begin with the most stringent control 

alternative, generally represented by LAER. 

The following is a brief outline of categories of 

control alternatives to consider and sources for identifying 

possible control alternatives. 

"Categories of Control Alternatives 

-Existing Control Technology -

Control technology which has been proven in 

practice for the category of source. 

-Technically Feasible Alternatives -

Control technology which has been demonstrated 

in practice on other source categories but has 

not been demonstrated in practice on the class 

or category of source under review. This is 

called control technology transfer. 

-Innovative Control Technology -

Control technology that has never been applied 

to any source on a full scale, continuously 

operating basis. This technology may be chosen 

on the basis of pilot scale or short term testing. 

-Production Processes, Fuels and Coatings that are 

Inherently Lower Polluting -

These options may be evaluated alone or in 

combination with add on pollution control devices. 

Examples include adjusting raw material feed to 

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P.13 

reduce emissions, methanol for low N0X applications, and the use of powder coatings where 

technically feasible. 

-Specific Design or Operational Parameters 

May include such factors as combustion zone 

temperature, combustion zone residence time, 

automatic combustion control systems, pressure 

drop across control equipment, etc. 

"Sources of Information on Control Alternatives 

There are numerous sources of information on 

control alternatives for various source 

categories. The following categories should 

all be considered when preparing a BACT analysis. 

-BACT/LAER Clearinghouse 

All applicants should be required to check the 

BACT/LAER Clearinghouse prior to submitting an 

application. The information contained in the 

Clearinghouse should be summarized in the 

application. Reviewing agencies should verify 

that this information is correct and up to date. 

The BACT/LAER Clearinghouse will be undergoing 

extensive revisions in format and accessibility 

in the near future. 

-EPA/State/Local Air Quality Permits 

Applicants may be aware of permitting and siting 

activities in their industry. An effort should 

be made to obtain current information on BACT 

for these sources. Permitting agencies should 

maintain documentation of recent BACT 

determinations. 

-Federal/State/Local Permit Engineers 

Permit engineers and engineering managers can 

provide information on projects under review for 

which BACT information may be available. BACT 

determinations under consideration will be 

available from these sources before it appears 

in the Clearinghouse manual. 

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P.14 

-Control Technology Vendors 

Vendors have information on the latest control 

technology, cost information, and emission 

guarantees. 

-Consultants 

The use of consultants may be appropriate in 

the preparation of BACT options and to assist 

reviewing agencies that lack experience with 

certain industries. 

-Inspection/Performance Test Reports 

Recent test data may be useful in establishing 

emission limitations for sources. Inspection 

and performance test data may also reveal 

potential problems with control technology. 

'Requiring the Use of Clean Processes, Fuels and Coatings 

that are Inherently Lower Polluting. 

Both the source applicant and the reviewing agency 

should consider the use of clean processes, fuels, and 

solvents that are inherently lower polluting than what 

has been historically employed by a particular industry. 

The analyses for these alternatives should be conducted 

in the same manner as described in later sections for the 

more conventional BACT alternatives. A reviewing agency 

should seriously consider requiring the use of such alternatives should the BACT analysis justify their use based 

on environmental, economic, and energy factors. Examples include the use of a dry process cement plant vs. 

a wet design; powder coatings vs. solvent-borne coatings; gas vs. fuel oil; electric boost or all-electric 

glass furnaces vs. fossil fuel fired; fluidized bed coal 

combustion vs. conventional firing; etc. 

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P.15 

VI. EFFECTIVENESS RANKING OF CONTROL ALTERNATIVES 

Once the appropriate control alternatives have been 

identified, they should be ranked in order of control 

effectiveness, with the most effective control alternative 

at the top. This list should present an array of control 

alternatives, showing control efficiencies, economic costs, 

environmental costs, energy costs, and other costs. A chart 

should be prepared for each pollutant and for each emissions 

unit, or small group of units in the BACT analysis. These 

charts should be used for comparison of the control alternatives and should used to focus the selection of a 

control option as BACT. 

An example of a chart prepared for a municipal waste 

fired boiler has been included as Appendix B. The chart 

ranks the control alternatives for stack SO2 emissions 

from the facility. Note the section of the chart reserved 

for impacts of the control alternatives on unregulated 

and other pollutants. 

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P.16 

VII. IMPACT ANALYSIS OF CONTROL ALTERNATIVES 

There are three main impact analyses within the BACT analysis 

° Environmental Impacts 

" Energy Impacts 

" Economic Impacts 

These impacts are used by the applicant during the selection 

and justification of a control alternative as BACT. Although 

the impact analyses are an important part of the selection 

process, the applicant should consider the control effectiveness 

of the alternatives to be the decisive factor affecting BACT 

selection. 

"Environmental Impacts 

The first impact analysis is for environmental impact. 

The applicant should estimate the net environmental impact 

associated with each control alternative. Both beneficial 

impacts and adverse impacts should be discussed and, where 

possible, quantified. The analyses should.be presented in 

the form of the incremental impact of each control alternative 

relative to the most stringent system identified as a control 

alternative. 

When weighing environmental impacts, the analysis 

should consider all pollutants affected by the control 

alternative. This includes pollutants which are not 

currently regulated under the Clean Air Act but which may 

have a significant environmental impact. On June 3, 1986, 

the Administator of the EPA remanded a PSD permit to 

Region 9 with instructions to the Region to consider the 

effects of unregulated pollutants when making a BACT 

determination. The analysis of unregulated pollutants 

should be directed at developing an inventory of potential 

pollutants from a proposed source and evaluating the impact 

of each control alternative on those pollutants being considered for BACT (see Appendices C and D). 

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P.17 

The.following is a brief outline of some, but by no 

means all, of the environmental categories that should be 

considered during an analysis of environmental impacts. 

-Impacts of Unregulated Pollutants 

Dioxin/Furans 

Heavy metals 

Acid gases 

PM10 

Non-photochemically reactive or toxic solvents 

etc 

-Impacts on Air Quality 

" Ambient concentrations for increments and NAAQS 

° Visible emissions 

-Impacts on Water Quality 

-Solid Waste Disposal Impacts 

-Other Environmental Impacts 

"Energy Impacts 

The second impact analysis is for energy impacts. In 

conducting an energy impact analysis, the applicant should 

estimate the direct energy impacts of the control alternatives 

in units of energy consumption (BTU's, kWh, barrels of oil, 

tons of coal, etc.). The energy requirements of the control 

options should be shown in terms of total and incremental 

(units of energy per ton of reduction) energy costs. 

"Economic Impacts 

In evaluating the economics of various BACT control 

options, primary consideration should be given to the cost 

effectiveness of an option and not the economic situation 

of the source applicant. For control technologies that 

have been proven for the source category under review, the 

economic impact of requiring this technology on a source 

under review is less important than the control effectiveness (in dollars per ton of pollutant removed) of the 

option. Therefore, an applicant's ability to afford a 

control option should not greatly influence the choice of 

a control option as BACT, especially where these control 

options have been applied to that source category. 

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P.18 

In the economic impacts analysis the applicant should 

estimate the approximate costs of the different emission 

control alternatives. The analysis should include a complete 

explanation of procedures used for assessing the economic 

impacts, any supporting data, and an itemization and 

explanation of all costs. Credit for tax incentives should 

be included along with credits for product recovery costs 

and by-product sales generated from the use of the control 

system. 

An analysis of the cost of control options on the basis 

of dollars per ton of pollutant controlled should also be 

conducted for each pollutant subject to BACT. A comparison 

should be made to the costs of controls for other source 

categories and other industries. A complete economic analysis should compare costs of controls both within the specific 

source category under review and as a comparison of costs, 

on the basis of dollars per ton of pollutant removed, for 

other industries. 

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P.19 

VIII. COMPARISON WITH OTHER FACILITIES APPLYING A MORE STRINGENT BACT 

An agency implementing the PSD program and wishing to; 

impose a stringent BACT requirement may place the geographic 

area over which it has authority at a economic disadvantage; 

with respect to other geographic localities if the air pollution agencies in those other localities are willing to impose 

BACT requirements less stringent than those imposed elsewhere. 

In order to avoid this problem, and achieve national 

consistency, each BACT proposal less stringent than the most 

effective control for that source category must make two 

showings in order for the proposal to receive consideration. 

The project proponent must show that there are factors^ 

unique to the project that differentiate this project from • 

other projects in the source category permitted with more 

stringent limits. This showing of uniqueness should focus 

on those criteria that factor into the BACT analysis, i.e. 

energy, environmental, and other economic costs. 

For example, gas turbines have demonstrated N0X emissions 

of less than 10 ppm through the use of a combination of water 

injection and Selective Catalytic Reduction. This level is 

then the baseline against which any proposed level of emission 

reduction must be compared. A source proposing to locate in 

Alaska may wish to avoid using water injection, on the basis 

that water injection would create ice fog, which would be a! 

safety hazard and a negative environmental effect. The reviewing agency might agree that ice fog is a negative environmental 

effect, but, because of the low capital cost of water injection 

technology, require that water injection technology be installed 

and used during those time periods when ice fog would not be a 

hazard. 

The applicant should also make a showing that granting the 

request for a less stringent limit will not grant an undue , 

competitive advantage to other industries that are of the same 

source category, and would be constructing a similar new facility at the same time. The rigor of the analysis may range 

from certification by the applicant that the project would not 

cause a competitive advantage if permitted with less stringent 

controls, to an in-depth analysis comparing similar facilities 

nationwide. The degree of rigor should be determined on a 

case-by-case basis by the reviewing agency. 

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P.20 

The process of showing "no competitive advantage" serves 

as a cross check on the process of determining those factors 

unique to the source, and emphasizes the philosophy that the 

federal PSD program is not to be used as an economic force in 

determining national plant siting decisions. State and local 

land use planning agencies and governing bodies should make 

those decisions regarding economic and other favorable or 

negative siting incentives as they see fit. 

IX. SELECTION AND JUSTIFICATION OF A CONTROL ALTERNATIVE AS 

BEST AVAILABLE CONTROL TECHNOLOGY. 

If an applicant selects the most stringent control 

alternative available (LAER), then no further analysis 

is necessary for the regulated pollutant. An analysis for 

the impact on unregulated pollutants must still be 

conducted. If LAER is not proposed, then the applicant 

must identify all of the control alternatives for each 

subject pollutant and rank by control effectiveness. 

Once the economic, energy, and environmental impacts 

analyses have been completed for each of the control 

alternatives, the applicant now has all of the information 

necessary for the selection of a control alternative as 

BACT. 

LAER will be the starting point in any BACT analysis, 

and BACT will be presumed to be equal to LAER unless 

adequate justification showing circumstances unique to 

the proposed project are provided and justified. 

If the most stringent control alternative is rejected 

for a less stringent one, then the applicant must justify 

the selection by demonstrating that each rejected control 

alternative (representing a more stringent level of 

control for that pollutant) would result in unreasonable 

energy, environmental, or economic impacts on the proposed 

project. This procedure must be conducted for each 

pollutant, until the applicant arrives at a set of 

controls for the entire source or modification subject 

to BACT. 

The applicant should be aware that any economic or 

energy demonstration will be closely reviewed by the 

permitting agency and that only significant economic or 

energy impacts would be considered adequate justification 

for selection of a less stringent control alternative. 

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P.21 

AGENCY REVIEW OF NOMINATED CONTROL ALTERNATIVES 

In conducting a Best Available Control Technology 

review, the reviewing agency must keep in mind that the 

applicant is proposing a set of emission limitations and 

control technology as BACT. The reviewing agency may 

believe that more stringent controls can be achieved 

within the defined BACT criteria. Such decisions, 

however, should be based on solid technical information 

obtained from the sources listed above under Section V 

and the judgement of the reviewing engineer. 

In general, the recommended approach for determining 

BACT is to begin with the most stringent level of control 

achievable for the proposed emissions unit and justify, on 

the basis of the BACT criteria (energy, economic, and 

environmental considerations), why that level of control 

should or should not represent BACT, This approach, as 

opposed to beginning at a less stringent level of control 

and evaluating increasingly more stringent levels of 

control or choosing an average level of control for 

similar emissions units, offers the best opportunity of 

arriving at a BACT which will in fact be the best available 

for this source. A BACT analysis conducted in this 

manner also has the greatest opportunity to be technology 

forcing. Such an analysis will have evaluated and rejected 

those levels of control which have been found inappropriate 

for the source under review. 

Disagreement on the specific continuous emissions 

reduction or control technology representing BACT may 

lead to requests for additional information, informal 

meetings, and negotiations. 

Review agencies should be extremely cautious in 

engaging in a "negotiated BACT" with an applicant. 

Negotiations that are not open to all members of the 

public after the close of the public comment period 

may be classed as e_x parte communications, and may 

lead to charges of unethical conduct (such communications for EPA employees are governed by the Agency 

ethics guidelines). 

Reviewing the BACT analysis submitted by an applicant 

requires engineering knowledge, experience and judgement. 

Four questions that should guide the reviewing agency are 

discussed below. 

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P.22 

1. Is the analysis complete? 

The analysis should address all pollutants subject 

to BACT and all emissions units that are part of 

the proposed source or modification. 

2. Is the analysis thorough? 

If an applicant proposes LAER as the control alternative, no further analysis is required other than 

an evaluation of the control of unregulated pollutants. If LAER is not chosen, the applicant should 

identify and provide detailed information on all 

possible BACT control alternatives, from LAER down to 

the control alternative proposed. The reviewing 

agency must, independently, attempt to identify 

control alternatives not evaluated by the applicant. 

The applicant should be required to evaluate any 

control alternatives identified by the agency. 

3. Are the cost estimates used reasonable? 

The reviewing agency must be very rigorous in evaluating 

the cost data submitted by the applicant. Cost data for 

similar projects may vary significantly depending on the 

assumptions used by the applicant. The reviewing agency 

must independently confirm the cost data used by the applicant. 

4. Has the applicant proposed the appropriate BACT for 

the source? 

Utilizing the technical resources available and the 

best engineering judgement of the reviewing engineer, 

the agency should make its own BACT determination 

for the proposed source. Where the applicant and 

the reviewing agency disagree, the applicant should 

be afforded the opportunity to provide additional 

information to justify the BACT proposal. Where a 

disagreement continues, the reviewing agency should 

propose for public comment the agency's determination 

of BACT. 

Finally, it must be noted that the BACT analysis is 

a separate analysis from the air quality analysis. A 

stringent BACT will not be dismissed because of a low 

impact on ambient air quality. However, a PSD permit may 

not be issued if a National Ambient Air Quality Standard 

or PSD increment would be violated due to the added 

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P.23 

em issions from the source at the permitted emissions 

level. If such violations are predicted, the source must 

propose to the permitting agency a method of reducing 

emissions so that there will be no violations. This 

proposal may involve additional controls at the source, 

creditable emissions reductions from other sources, a 

downsized facility or a combination of the above. 

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P.24 

XI. CONSTRUCTION PERMIT REQUIREMENTS 

A good BACT determination is of little value if the 

implementation of the BACT controls and emission limits 

cannot be enforced by the issuing agency and by EPA. For this 

reason, the construction permit issued (and an operating 

permit, for those agencies using a two tiered permit system) 

following a PSD review must have enforceable limits and 

prescribe methods of determining compliance with those limits. 

Appendix E to this report summarizes the types of conditions necessary for a properly written permit. However, the 

key point that should be stressed when formulating a permit 

is that federally enforceable emissions limitations representative of BACT must be included in the permit (The PSD regulations do, however, provide for the imposition of an equipment 

or work practice standard where an emission limitation is not 

possible, such as with fugitive emission sources). The 

emissions limits must also enable the permitting agency to 

enforce the requirement that BACT is a continuous system of 

emissions reduction, requiring equivalent levels of control 

at all levels of production. 

In order for an emission limit to be federally enforceable, 

it must meet the tests of being enforceable as a practical 

matter, and must also be specifically enforceable by EPA under 

§113 of the Clean Air Act. 

"Permits must be Enforceable as a Practical Matter 

An enforceable limit is one that allows the Agency to 

determine compliance at any time. Such a limit must meet two 

tests. 

First, the limit must be compatible with established methods 

of determining compliance. Emission limits in terms of ppm, 

grains/dscf (at a specified percent O2 or CO2), pounds/ million 

BTU, pounds per hour, and grams per liter generally meet this 

test. Emissions limits written as pounds per day or tons per 

year do not meet this test. Averaging times must be also specified and must be compatible with accepted ways of determining 

compliance. Permit conditions using an emission limit in terms 

of heat input or fuel use, such as pounds per million BTU or 

pounds per ton of material processed, or emission limits with 

long averaging times, such as pounds per day or tons per year, 

must be coupled with emission limits such as the following. An 

emission limit expressed in ppm corrected to 12% C02» three hour 

average, using an approved test method is the recommended 

approach. 

-19-
P.25 

Second, it must also be supported by compliance monitoring requirements that enable the source to show continuing 

and continuous compliance. In the past, EPA has placed great 

emphasis on one time or annual testing, using continuous 

monitors and surrogates (such as mass of water injected into 

a gas turbine) only as indications of a compliance problem. 

However, the technological advancement of continuous emissions 

monitors (CEMs) and the realization of the need for enforceable 

mechanisms other than annual source tests has led EPA to write 

permits which contain requirements for continuous compliance 

with emission limitations. EPA issued permits generally '. 

require CEMs where their use is technically possible. 

"Permit Conditions Must be Federally Enforceable 

Even when an EPA regional office is not the permitting 

agency, EPA must be specifically able to enforce all permit 

conditions relating to BACT determinations. Certain types of 

conditions may be enforceable by a state or local agency, but 

are not necessarily federally enforceable. The definition found 

at 40 CFR 52.21(b)(17) spells out those documents, including 

PSD permits, which may contain federally enforceable restrictions, 

Thus, an outside document, such as a contract between two permittees, is not federally enforceable unless it is specifically 

incorporated in the PSD permit and is enforceable against the 

permittee. Any condition in the PSD permit must also meet the 

requirements of Section 113 of the Clean Air Act, which spells 

out EPA's enforcement power and obligations. Key points to 

keep in mind are (1) the need to use those test methods found 

in 40 CFR Parts 60 and 61, unless an equivalent method is 

specifically approved by the Administrator, and (2) the heed to 

be able to demonstrate a violation continuing for thirty days 

for any permit condition. 

"Public Participation 

Each PSD permit is required to go through a process of 

public review and comment, usually a minumum of 30 days.- Public notice and comment is also important to the BACT process, 

in that information received from the public (including 

industry, public agencies, public interest groups and individual 

citizens) regarding the proposed BACT determination must be 

taken into account in the final BACT determination. 

"Phased and Delayed Construction 

The PSD regulations require that a re-assessment of BACT 

be made for each independent phase of a multi-phase project. 

This re-assesment should occur within eighteen months of the 

-20-
P.26 

start of construction of that phase. EPA is currently 

developing policy regarding the manner in which BACT 

will be determined for projects proponents requesting 

extensions of the construction schedule and for 

those requesting changes in the PSD permits. 

XII. BACT FLOWSHEET 

Attached as Appendix A is a simplified flowsheet 

outlining the processes described in this guideline. 

It may be used as a ready reference; however, the user 

should refer to the detailed guideline to understand all 

details of the outline. 

XIII. CONCLUSION AND SUMMARY 

The process outlined here for determining BACT 

will, if used conscientiously, ensure that permit 

applicants can use a consistent approach in submitting 

BACT proposals to permitting agencies. Fewer instances 

of new industrial sources being discouraged because of 

uncertainty at the permitting stage are likely to occur. 

Permitting agencies will know that permit shopping 

should be less likely to occur. Moreover, the PSD 

provisions of the Clean Air Act will be properly 

carried out. 

-21-
APPENDIX A 

BACT FLOWSHEET 

(To be Used by Applicant in Proposing BACT) 

STEP 1 

Determine the most stringent emission limit 

required or achieved in practice (or Lowest 

Achievable Emission Rate, LAER) for each 

pollutant for which BACT is required. Also 

examine emerging technologies and technology 

transfer. 

If LAER is selected, and this technology 

represents the greatest degree of control 

for the unregulated pollutants, skip steps 

2 through 7. Otherwise, go to step 2. 

STEP 2 

List all available control alternatives other 

than LAER for each pollutant subject to BACT. 

Survey BACT/LAER Clearinghouse and control 

agency data to ensure possible controls are 

not bypassed. 

STEP 3 

Prioritize control alternatives identified in 

Step 2 based on energy, economic and other 

environmental costs, including unregulated 

pollutants as per Appendix C and D and with 

respect to control effectiveness. 

STEP 4 

Analyze the control level identified in Step 1 

and all alternatives in Step 2 for practical 

application as a BACT proposal. 

STEP 5 

If LAER is not selected as the BACT proposal, 

provide adequate justification. 

STEP 6 

If the next most effective control alternative 

is not selected as the BACT proposal, provide 

adequate justification. 
P.28 

STEP 7 

STEP 8 

STEP 9 

STEP 10 

STEP 11 

STEP 12 

STEP 13 

Go to Step 6, until a BACT proposal is 

reached. Then go to Step 8. 

Is the control alternative (a) appropriate for 

the BACT proposal, (b) more stringent than the 

NSPS level, and (c) protective of the NAAQS and| 

the PSD increments? 

Express BACT determination as an enforceable 

numerical limitation for each permit unit/ 

pollutant (normally expressed so that emission 

follow production rate; pound per hour limits 

are necessary to protect air quality, and may, 

in some cases, be BACT limits). 

Public notice specifically identifying propose 

BACT. 

Respond to public comment on BACT and modify 

BACT determination based on public comment 

if appropriate. 

Issue construction permit; enter 

determination in clearinghouse. 

Where applicable, after construction is 

completed, issue operating permit 

incorporating the BACT technology, enforceable BACT emission limit, CEM requirements, 

etc. 

-2-
APPENDIX B 

EPA Region 9 - New Source Section 

BACT ANALYSIS 

(Ranked in Decreasing Order of Control Effectiveness) 

Project: 

Project Category: Resource Recovery 

Project Type: 1113 IPP, RDF, 36 MW 

Pollutant: SO? 

Date: 

Project Engineer: 

Control Options 

Spray Dryer, Alkaline 

Slurry, Baghouse 

Spray Dryer, Lime Slurry 

Baghouse 

Dry Injection, Sodium 

Sorbent, Baghouse 

Spray Dryer, Alkaline 

Slurry, ESP 

Spray Dryer, Lime Slurry 

ESP 

Dry Injection, Lime, 

Baghouse 

Dry Injection, Sodium 

Sorbent, ESP 

Wet ScriJabing, Alkaline 

Dry Injection, Lime, ESP 

% Control 

80-95 

75-90 

70-85 

75-90 

65-85 

65-80 

50-75 

50-90+ 

40-70 

Buission 

Rates 

lbs/ton 

(ppm) <* 

0.26-1.04 

(9-35) 

0.52-1.30 

(18-44) 

0.78-1.56 

(26-53) 

0.52-1.30 

(18-44) 

0.78-1.82 

(26-62) 

1.04-1.82 

(35-62) 

1.30-2.61 

(44-88) 

0.52-2.61 

(18-88) 

1.56-3.13 

(53-106) 

Emissions 

(tons/yr ) 

53-212 

106-265 

159-318 

106-265 

159-371 

212-371 

265-530 

106-530 

318-636 

Annualized 

Oost <2 

($1,000) 

-

Cost 

Effectiveness 

($/Ibn) 

Oontrol Effectiveness on 

Other Pollutants 

Heavy 

Metals 

Exc 

Exc 

Exc 

Good 

Good 

Good 

fiair 

Poor 

feiir 

Dioxin 

Furans 

Exc 

Exc 

Poor 

Good 

Good 

Poor 

Poor 

Poor 

Poor 

Ha 

Exc 

Exc 

Exc 

Exc 

Exc 

Exc 

Exc 

Exc 

Good 

Hg 

Good 

Good 

Poor 

Fair 

Paic 

Poor 

Poor 

feiir 

Poor 

Lead 

Exc 

Exc 

Good 

Good 

Good 

Good 

Feiir 

Feiir 

Fait: 

(1 Oorrected to 12% 002 

(2 Assumes % interest amortized over 30 years + operating costs. 
APPENDIX B 

EPA Region 9 - New Source Section 

BACT ANALYSIS 

(Ranked in Decreasing Order of Oontrol Effectiveness) 

Page 2 

Project: 

Project Category: Resource Recovery 

Project Type: 1113 IPP, RDF, 36 MW 

Pollutant: S0? 

Date: 

Project Engineer: 

Oontrol Options % Cbntrol 

Qnission 

Rates 

lbs/ton 

(ppm) d 

Omissions 

(tons/yr) 

Annualized 

Cost <2 

($1,000) 

Oost 

Effectiveness 

($/Ibn) 

Oontrol Effectiveness on 

Other Pollutants 

Heavy 

Metals 

Dioxin 

furans 

HC1 Hg Lead 

Dry Injection, Limestone 

ESP 

Wet Scrubbing, Water 

Source Separation 

25-40 

20-30 

5-10 

3.13-3.91 

(106-132) 

3.65-4.17 

(124-141) 

4.69-4.95 

(159-168) 

636-795 

742-848 

954-1007 

Fair 

Poor 

Poor 

Poor 

Poor 

Ffcir 

Good 

Bair 

Eetir 

Poor 

Poor 

Poor 

Fair 

Fair 

Poor 

(1 Corrected to 12% 002 

9 ^ inojMEt :iz | ive yee ine stsj CO 
P.31 

« < > 

APPENDIX C 

BEFORE THE ADMINISTRATOR 

U.S. ENVIRONMENTAL PROTECTION AGENCY 

WASHINGTON, D.C . 

In the Matter of: 

North County Resource 

Recovery Associates 

Applicant 

PSD Appeal No. 85-2 

REMAND 

In petitions filed pursuant to 40 CFR §124.19 (1985), 

Donald J. Wakefield and John R. Leach Jr., jointly, and Stephen 

Isaac and Richard D. Sauerheber, individually, requested review 

of a Prevention of Significant Deterioration (PSD) permit 

determination that will authorize North County Resource Recovery 

Associates (NCRR) to construct a 33 megawatt, 1000 ton per day 

resource recovery facility in San Marcos, California. The 

determination to issue the permit was made on March 22, 1985, 

by the Director, Air Management Division, U.S. Environmental 

Protection Agency, Region IX, San Francisco, California. 

Petitions for review of PSD permits are not usually granted 

unless the permit determination is clearly erroneous or involves 

an exercise of discretion or policy that is important and therefore should be reviewed as a discretionary matter, 40 CFR 

§124.19(a)(1) and (2). The preamble to the regulations containina 

this standard states that "this power of review should be only 

sparingly exercised [and] . . . most permit conditions should 

be finally determined at the Regional level. ... " 45 Fed. 

Reg. 33412 (May 19, 1980). The burden of demonstrating that 
P.32 

< ' * 

-2-

the permit conditions should be reviewed is therefore on the 

petitioners. 

Among the reasons the petitioners present for arantinq review is Region IX's alleqed failure to establish emission limitations for all pollutants, includinq hazardous pollutants, 

that will or could possibly be emitted from the facility; the 

alleged inadeciuacy of Best Available Control Technoloqy (BACT) 

determinations; the alleged use of unrepresentative meteoroloaical data; the contention that the Complex I air dispersion 

model for predicting pollution levels is inappropriate; and 

miscellaneous matters such as the contention that the impact of 

emissions on vegetation was not properly evaluated. With one 

exception, Region IX has addressed each of petitioners' alleqations and has provided rational explanations for not making any 

alterations in its permit determination. The exception concerns 

Region IX's assertion that EPA lacks the authority to "consider" 

pollutants not regulated by the Clean Air Act when making a PSD 

determination. This assertion is correct only if it is read 

narrowly to mean EPA lacks the authority to impose limitations 

or other restrictions directly on the emission of unregulated 

pollutants. EPA clearly has no such authoritv over emissions of 

unregulated pollutants. Recion IX's assertion is overly broad, 

however, if it is me.ant as a limitation on EPA's authority to 

evaluate, for example, the environmental impact of unregulated 

pollutants in the course of making a BACT determination for the 

regulated pollutants. EPA's authority in that respect is clear. 
P.33 

• t 

-3-

Under §165(a)(4) of the Clean Air Act and the relevant 

regulations a proposed facility is subject to the "best available control technology" (BACT) for each pollutant that is 

regulated by the Act that is emitted from, or which results 

from, such facility in significant amounts, 42 USC §7475(a)(4); 

40 CFR §52.21(i)(1985). As defined in §169(3) the term BACT 

refers to an "emission limitation" that is set on a case-by-case 

basis for regulated pollutants, "taking into account energy, 

environmental, and economic impacts and other costs" associated 

with the particular emission control system that is selected tp 

achieve the BACT emission limitation. 42 USC §7479(3) (emphasis 

added); 40 CFR §52.21(b)(12). Hence, if application of a 

control system results directly in the release (or removal) of 

pollutants that are not currently regulated under the Act, the 

net environmental impact of such emissions is eligible for 

consideration in makinci the BACT determination. The analysis 

may take the form of comparinq the incremental environmental 

impact of alternative emission control systems with the control 

system proposed as BACT; however, as in any BACT determination, 

the exact form of the analysis and the level of detail required 

will depend upon the facts of the individual case. Depending 

'.•pon what weight is assigned to the environmental impact of a 

particular control system,' the control system proposed as BACT 

may have to be modified or be reiected in favor of another system. In other words, EPA may ultimately choose more stringent 

emission limitations for a regulated pollutant than it would 
P.34 

-4-

otherwise have chosen if settinq such limitations would have 

the incidental benefit of restricting a hazardous but, as yet, 

1/ 

unregulated pollutant. 

After reviewing Region IX's responses to petitioners' 

comments and to their petitions for review, it is unclear to me 

whether Region IX has given appropriate consideration to the 

matters iust described. Petitioners have expressed understandable frustration at being told, without more, that "EPA 

does not have the authority to consider dioxin or most other 

toxic air contaminants for the purpose of issuing a PSD permit." 

Accordingly, I am remanding the permit determination to Region 

IX for reconsideration and for action consistent with the fore— 

qoino interpretation of EPA's authority to consider uTtregulated 

pollutants when makinq PSD determinations. In the meantime a 

rulinq on the Dendinq petitions for review will be held in 

abeyance. 

So ordered. 

^v^— •V 

Lee M. Thomas 

Administrator 

Dated: 

3 )UL 

JL/ Industry engineers would remain free, of course, to exercise 

their own independent iudgment in devisinq ways to meet any 

such more strinoent emission limitations, provided the enerqy, 

environmental and economic impacts associated with the chosen 

control system are not inconsistent with the corresponding impacts associated with the more strinqent emission limitations. 

See In the Matter of CertainTeed Corporation at 5-8, PSD Appeal 

No. 81-2 (Decision of the Administrator, December 21, 1982). 
V « 

APPENDIX D 

BEFORE THE ADMINISTRATOR 

U.S . ENVIRONMENTAL PROTECTION AGENCY 

WASHINGTON, D.C. 

In the Ma tt e r of: 

North County Resourc e 

Recovery Associate s 

Appl i cant 

PSD Appeal No. 85- 2 

ORDER DENYING REVIEW 

In petition s file d pursuant to 40 CFR $124.1 9 (1985) , 

Donald J . Wakefield and John R. Leach, Jr. , Jointly , and 

Stephen Isaa c and Richard D. Sauerbeber , individually , 

requeste d review of a Preventio n of Significan t Deterioratio n 

(PSD) permit determinatio n tha t wil l authoriz e North County 

Resourc e Recovery Associate s (NCRR) t o construc t a 33 megawatt, 

1000 ton per day resourc e recover y facilit y i n San Marcos, 

California . The permit determinatio n was made by the U.S . 

Environmenta l Protectio n Agency , Region IX, San Francisco , 

California . 

On June 3 , 1986 , ln respons e t o the petitions , I 

Issue d an orde r remanding the permit t o Region IX fo r 

reconsideratio n of the basis on which l t had made it s Best 

Availabl e Contro l Technolog y (BACT) determination s fo r the 

permit. Specifically , Region IX was t o take int o accoun t 

the environmenta l effects , i f any, of pollutants tha t ar e 
. * 

-2-

not currently regulated under the Act, if such pollutants 

are released (or removed) through application of the control 

system designated as BACT. 

On August 15, 1986, Region IX wrote a response to the 

remand order that reaffirmed the prior BACT determinations. 

Region IX found that the emission controls reflected In its 

original BACT determinations were such that no other controls 

on regulated pollutants would be more effective ln reducing 

emissions of unregulated pollutants. In other words, 

alternative controls for the regulated pollutants would not 

offer any better control for unregulated pollutants than the 

controls proposed by NCRR. Accordingly, pursuant to the 

terms of the remand order, this matter is now ripe for a 

decision on whether NCRR's permit should be reviewed on 

appeal or whether Region IX's decision to issue the permit 

should be allowed to become final. 

Petitions for review of RCRA permits are not granted 

unless the permit determination is clearly erroneous or 

Involves an exercise ot discretion or policy that Is important 

and therefore should be reviewed as a discretionary natter, 

40 CFR §124.19 (a)(1) and (2) (1985). The preamble to the 

regulations containing this standard of review states that 

"this power of review should be only sparingly exercised (and) 

. . . most permit conditions should be finally determined at 

the Regional level . . . ." 45 Fed. Reg. 33412 (May 19, 1980) . 
t. 1 » 

- 3 -

The burden of demonstratin g tha t the permit condition s should 

be reviewed is therefor e on the person requestin g review . In 

this case , the partie s requestin g review have not, i n my 

opinion , raise d any matter s that warrant review under the 

applicabl e standard of review . An examinatio n of the record 

on review disclose s tha t the Regiona l Administrato r has give n 

thorough and carefu l consideratio n t o al l of the issue s raise d 

by the person s requestin g review and the permit determinatio n 

is neithe r clearl y erroneou s nor involve s an exercis e of 

discretio n or polic y which warrants discretionar y review . 

Accordingly , the petition s fo r review ar e denied . 

In accordanc e wit h 40 CFR § 124 .19 ( f) ( 1) and (2) , Region IX 

shal l issu e a fina l permit decisio n consisten t wit h this orde r 

and publis h notic e of tha t decisio n In the Federa l Register . 

The decisio n shal l be considere d fina l Agency actio n fo r 

purpose s of judicia l review . 

So o rde red . 

/P'T R 

6/2 -J 4m++- U>«c~ 

<\*«JL> 

frCTinC 

I a a Mi—T horea6 , 

Admi ni s t rato r 

DATED: $EP 4 1986 
P.38 

APPENDIX E 

PERMIT REQUIREMENTS 

Each permit should contain: 

1 Identification of all points of emission (both stack and 

fugitive). 

2. Inclusion of a numerical emission limitation for each 

point of emission in terms of mass rate or concentration 

limitations. If emission testing based on a numerical 

emission limitation is infeasible, the permit may instead 

prescribe a design, operational, or eguipment standard. 

Any permits issued without numerical emission limitations 

must contain conditions which assure that the design 

characteristics or equipment will be properly performed so 

as to continuously achieve the assumed degree of control. 

3. Limitations or factors which were the basis for air quality 

impact analysis must be specified (e.g., hours of operation, 

stack height, materials processed which affect emissions). 

4. Methods and frequency of determining continued compliance 

for each emissions point should be stated in the permit and 

should reference the appropriate section of the NSPS, NESHAPS 

or SIP approved test procedures. 

5. Recordkeeping requirements which enable the agency to 

ascertain continued compliance especially where factors such 

as hours of operation, throughput ot materials, sulfur content of fuels, fuel usage, or type or quantity of materials 

processed are conditions of the permit. 

6. A statement that the permit will expire if construction has 

not commenced by a specified date, is discontinued more than 

18 months, or is not completed in a reasonable time. 

7. A statement that the source is responsible for providing 

sampling and testing facilities at its own expense. 

3. Reporting requirements which enable the agency to monitor the 

progress of source construction and compliance, including 

the date by which construction is completed, and, if different 

from the completion of construction date, the date by which 

final compliance is to be achieved. 
P.39 

4k '-

•I «* t 

9 Identification of all offsets, with conditions requiring 

implementation of offsets by a date specified, identification 

of all banked emissions offsets which are to be applied; 

identification of all emission credits allocated to the 

source from the growth allowance. 

10 As a courtesy to sources exempted from PSD/NSR review 

due to federally enforceable operational or process 

restrictions, or the use of controls more stringent than 

required by applicable SIP limits, the source should be 

advised that any relaxation of those limits may subject 

the entire source to full PSD/NSR review as if construction 

had not yet begun. Suggested language is a follows: 

"This source is exempt from PSD/NSR review because 

of (e.g., "a requirement that operation is limited 

to eight hours per day"). Any relaxation in this 

limit that increases your potential to emit above 

the applicable PSD/NSR threshold will require a 

full PSD/NSR review of the source as though 

construction had not yet commenced on the source."