Best available control technology (BACT) requirements PowerPoint Presentation

Best available control technology (BACT) requirements

Roland C. Hea, P.E.

Colorado Air Pollution Control Division

Main PSD Program Requirements

2

Install

Best Available Control Technology (BACT)

Perform

air quality analysis

to assess impacts on air quality (NAAQS and PSD increments)

Perform

Class I Area analysis

to

assess impacts on

national parks and wilderness areas or other Class I Areas

Perform

additional impacts analysis

Provide opportunities for

public involvement

BACT – Major Topics

3

When does BACT apply

Steps in the “Top Down” BACT analysis

What does a BACT determination and limit look like

Greenhouse gas (GHG) BACT issues

State (Colorado) perspectives

Best Achievable Control Technology (BACT) Overview

4

Pollutant specific emissions limit, case-by-case

Takes into account energy, environmental, or economic impacts

Limit must be at least as stringent as applicable

New Source Performance Standard (NSPS) and/or

National Emission Standard for Hazardous Air Pollutants (NESHAP)

Selected by “Top Down” BACT analysis

Identify all available control technologies

Eliminate technically infeasible control options

Rank remaining control technologies by its effectiveness (considering economic, energy and environmental impacts)

Evaluate most effective controls and document results

Select BACT

5

BACT Applicability

Identify emissions units that are subject to BACT

Applies to each individual new or modified affected emissions unit or activity at which a net emissions increase would occur

Perform BACT analysis at each of the applicable emissions units for each regulated pollutant subject to PSD review

BACT Analysis Step 1

6

Identify all available air pollution control technologies, regardless of cost

Information sources

Review RACT/BACT/LAER Clearing House

http://cfpub1.epa.gov/RBLC/

Look at BACT

and

LAER

Control technology vendors

Federal/state/local NSR permits

Environmental consultants

Technical journals (e.g., Journal of Air and Waste Management Association) and air pollution conferences

EPA’s Draft October 1990 NSR Workshop Manual

BACT Analysis Step 1 (cont.)

7

Include technologies used outside the U.S.

Include controls applied to similar categories and gas streams

Review applicable NSPS and NESHAP (including MACT), which define minimal “floor” for BACT

Consider

Inherently lower-emitting processes/practices

Add-on controls (e.g., scrubbers, fabric filters)

Combination of inherently lower-emitting processes/practices and add-on controls

BACT Analysis Step 1 (cont.)

8

EPA has not considered

BACT

requirement as a

means

to redefine

design

of a source when considering available control technology

For example, EPA does not require coal-fired electric generators to consider gas-fired electric turbines

Colorado takes the same position on this issue

BACT Analysis Step 2

9

Eliminate technically infeasible control options

Source must demonstrate technical infeasibility, based on physical, chemical, and engineering principles

If someone has issued a permit requiring a certain technology or emission limit, assumption is that the technology or limit is technically feasible (Colorado uses its permitting discretion to assess this aspect)

BACT Analysis Step 2 (cont.)

10

Where control technology has not been installed and operated successfully on the type of source under review, feasibility is determined based

on

Availability (i.e., product has reached licensing and commercial sales stage of development)

Applicability

C

ontrol alternative has or will be deployed on same or similar source type, or

Could be used on source based on physical and chemical characteristics of pollutant-bearing gas stream

BACT Analysis Step 2 (cont.)

11

Applicant may show technical infeasibility through an unresolvable technical difficulty with applying the control (e.g., size of unit, location of proposed site, operating problems related to specific circumstances of source)

Applicant may not use cost to demonstrate infeasibility, but may be considered in economic impacts portion of BACT analysis

Class exercise

12

Please see handout

BACT Analysis Step 3

13

Rank remaining control technologies according to control effectiveness. For each pollutant, list

includes

Control efficiency (percent of pollutant removed)

Expected emissions reduction (tons/year)

Economic Impacts

Environmental Impacts (e.g., significant impact on surface water)

Energy Impacts

BACT Analysis Step 3 -Control Efficiency

14

Two key questions

How to compare apples to apples (deciding common unit for comparing the emissions of each option)

How to analyze control techniques that can operate over a wide range of emission performance levels

Tips: what to watch for

Observations: major issues in this area

BACT Analysis Step 3 - Expected Emissions Reductions (tons/year)

15

Calculate annual emission projections for each option using standard PTE approach

Options ranked with top spot going to control technology option that achieves lowest emissions level, in descending order of emissions control effectiveness

BACT Analysis Step 3 – Economic and Other Impacts

16

Applicant prepares list to display top-down ranking, and for each alternative includes data

on

Economic impacts

Environmental impacts (i.e., non-air quality impacts)

Energy impacts

BACT Analysis Step 3 – Economic Impacts

17

Economic impacts include

Average cost effectiveness (dollars per ton of emissions reduced) based on data from similar sources

I

ncremental cost effectiveness

Affordability to source is not as relevant as average and incremental cost-effectiveness

Where control technology has been successful for similar sources, applicant need to document significant cost differences for its source to eliminate control alternative

BACT Analysis Step 3 – Economic Impacts (cont.)

18

Key issues for cost effectiveness

Ensure that design parameters used in cost estimates are consistent with emissions estimates used in other portions of PSD application (e.g., dispersion modeling inputs and permit emission limits)

Ask for more detailed cost data if cost projections appear excessive in light of recent cost data

BACT Analysis Step 3 – Economic Impacts (cont.)

19

Average cost effectiveness

Total annualized costs of control, divided by

Annual emission reductions (the difference between the baseline emission rate and the controlled emission rate)

Major issues

Underestimation of PTE

Overestimation of annualized costs

Inclusion of indirect costs that should not be considered in a BACT analysis (see EPA control cost manual)

BACT Analysis Step 3 – Economic Impacts (cont.)

20

Incremental cost effectiveness compares costs and emissions performance level of a control option to the next most stringent option

Calculation

Total annualized cost of option 1 minus total annualized cost of option 2 (less stringent option), divided by

Option 2 emission rate minus option 1 emission rate

BACT Analysis Step 3 – Environmental Impacts

21

Environmental impacts should include

any significant or unusual other media impacts (e.g., water or solid waste)

Usually limited to discharges with potential for causing adverse environmental effects

Quantify mass and composition of discharges and consequences of release

Impacts on ground water and local surface water; whether applicable water quality standards will be met; availability/effectiveness of mitigation techniques

Quality and quantity of solid waste to be stored, disposed of or recycled (including permeability, water retention, leachability, hazardous characteristics, etc.)

Irreversible or irretrievable commitment of resources (e.g., scarce water resources)

Significant differences in noise levels, radiant heat, dissipated static electrical energy and greenhouse gas emissions

BACT Analysis Step 3 – Environmental Impacts (cont.)

22

Environmental impacts should include the relative ability of each control alternative to control emission of HAPs and visibility impacts

Examples where environmental factors have made a difference in a BACT analysis

Aqueous versus anhydrous

a

mmonia

Dry vs. wet scrubbing for a coal-fired power plant

Local water table low, thus dry cooling better option

Environmental concerns become important when site-specific receptors exist

Application to tribal issues – discuss with class

BACT Analysis Step 3 – Energy Impacts

23

Generally consider only direct energy consumption of alternative control technologies

Quantify any benefits or penalties

Typically can monetize these impacts and factor them into the economic impacts analysis

BACT Analysis Step 4

24

Evaluate most effective controls based on all the factors in Step 3

D

ocument results

Sample Top-Down BACT Determination

25

Small group

exercise: Each

group makes a recommendation on BACT

Discuss results

BACT Analysis Step 5

26

Ultimate BACT decision is made by permitting agency after public review

BACT is based on most effective control option for which adequate justification for rejection not provided

Public gets at least 30 days to review draft permit

Practical advice for reviewers

Public comment hearing provisions

Permitting agency will consider any new information revealed during comment period, including recent permit decisions

Implementing BACT

27

BACT is an emission limit

that

Is needed for each emission unit at a source, subject to PSD for each pollutant subject to review that is emitted by source

Must be met continually at all levels of operation

Alternate BACT limits may be needed for other operational scenarios (e.g., startup/shutdown)

Must protect short-term ambient standards (limits and averaging times)

Specifies a control technology or practice, numerical limit and averaging time

Implementing BACT (cont.)

28

Incentive to operate efficiently

BACT can be made more stringent if initial BACT emission levels would result in a NAAQS or a PSD increment to be exceeded

P

roposed source or modification still has to demonstrate compliance with other standards included in the PSD analysis

Must be enforceable as a practical

matter

M

onitoring considerations for demonstrating on-going compliance

Greenhouse Gas Considerations

29

Relatively new, agencies have less experience implementing

Energy efficiency

Setting numerical limits and averaging times

Carbon capture and sequestration

See http://www.epa.gov/nsr/ghgpermitting.html

Summary

30

Major stationary sources and major modifications that are subject to PSD must conduct a BACT analysis

Each BACT analysis is case-by-case and is based on evaluation of all available control technologies

Alternatives are ranked in descending order of control effectiveness

The most stringent or top alternative is BACT unless the applicant demonstrates that technical considerations or energy, environmental or economic impacts justify the elimination of the control option