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To: US EPA OAQPS 

From: SRA International, Inc.

Subject: Review of CoST Model Emission Reduction Estimates

Date: September 30, 2014

EPA uses the Control Strategy Tool (CoST) to estimate the emission reductions and engineering costs 

associated with control strategies applied to point, area, and mobile sources of air pollutant emissions to 

support the analyses of air pollution policies and regulations. CoST accomplishes this by matching 

control measures to emission sources using algorithms such as "maximum emissions reduction", "least 

cost", and "apply measures in series". There was a concern that the baseline inventory used by CoST did 

not completely account for emission control requirements already in place, and that the emission 

reductions were perhaps overestimated. 

SRA reviewed the CoST results and made recommendations for changing the CoST control measure 

assignment and the estimated reductions for oxides of nitrogen (NOx). The recommendations were based 

on a review of source permits, state regulations, enforcement actions, and other available information. 

The analysis was conducted for a 24-state area in the eastern two-thirds of the U.S. The focus was on 

stationary point sources other than electric generating units (non-EGUs). The purpose of this memo is to 

document the data used and assumptions made in recommending changes to the CoST results, and to 

summarize the differences between the CoST results and the recommended changes. 

The findings in this memo are based on review of CoST results for a 2018 emissions inventory projected 

from the 2011 National Emission Inventory (NEI). This work was in support of EPA’s current Transport 

Rule efforts for implementing the 75 ppb ozone standard. If EPA considers establishing a tighter ozone 

standard in the future, it is likely that a more distant future year will be used and that some of the 

conclusions reached in this memo could change.

CoST DATA PROVIDED BY EPA

EPA provided SRA with the outputs from a CoST scenario that identified sources for which NOx controls 

were available at a cost-effectiveness level of less than $10,000 per ton. The CoST outputs included 

source identifiers, control technology, baseline emissions and estimates of NOx emission reductions. The 

CoST results were divided into two groups. The first group included sources where CoST estimated NOx 

emission reductions of more than 100 tons per year. There were 547 sources in this group where CoST 

controls were initially applied. The second group included sources where CoST estimated emission 

reductions for sources whose 2018 projected emissions were greater than 25 tons/year, excluding those 
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with reductions greater than 100 tons/year. There were 1,280 sources in this group where CoST controls 

were initially applied.

Another contractor reviewed the CoST results for additional source categories, and their 

recommendations were merged with SRA’s recommendations in the summary tables and maps that 

follow. The data used, assumptions made and results for IC engines are documented elsewhere1. 

REVIEW OF CoST RESULTS FOR THE GREATER THAN 100 TPY GROUP

Table 1 summarizes the source categories included in our analysis, the CoST recommendation for NOx 

control, and the recommendation for changing the CoST control measure assignment and associated 

emission reduction estimates. Following Table 1, there is a discussion for each source group to provide 

more detail on the rationale for the recommended changes for each source group. Attachments 1 to 4 are 

tabular comparisons of the initial CoST emission reduction estimates and the recommended changes. All 

Attachments present the results in terms of tons per ozone season, simply estimated by assuming that 

ozone season emissions were equal to 5/12 of the annual emissions. Maps 1A and 1B graphically show 

the location of sources and the magnitude of the recommended emission reductions. 

Table 1 – CoST Controls and Recommended Changes for

Greater than 100 TPY Sources

Source Group CoST Control 

Recommendation

Summary of Recommended Changes to 

CoST Controls and Reductions

Ammonia – NG-fired 

Reformers

Selective Catalytic 

Reduction

Agreed with CoST recommendation of SCR 

except for those sources where a permit or 

state regulation already required the source 

to be controlled.

By-Product Coke Mfg; 

Oven Underfiring

Selective Non-Catalytic 

Reduction

Review of a source-specific NOx RACT 

permit indicated that NOx controls were 

technically or economically infeasible. 

Cement Kilns Biosolid Injection 

Technology

Disagreed with CoST recommendation

based on concerns about biosolids 

availability and information from EPA’s ISIS 

(Industrial Sector Integrated Solutions) 

Model; recommended SNCR for all sources, 

except those that already have SNCR due to 

NOx SIP Call, NSR requirement, Consent 

Decree, or other state regulation.

 

1 Update of NOx Control Measure Data in the CoST Control Measures Database for Four Industrial

Source Categories: Ammonia Reformers, NonEGU Combustion Turbines,Glass Manufacturing, and Lean 

Burn Reciprocating Internal Combustion Engines," prepared by Research Triangle Institute, July 2014.
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Source Group CoST Control 

Recommendation

Summary of Recommended Changes to 

CoST Controls and Reductions

Cement Manufacturing 

- Dry

Selective Non-Catalytic 

Reduction

Agreed with CoST recommendation except 

when already controlled due to NOx SIP Call, 

NSR requirement, Consent Decree, or other 

state regulation.

Cement Manufacturing 

– Wet

Mid-kiln Firing Disagreed with CoST recommendation

based on information from EPA’s ISIS Model; 

recommended SNCR for all sources, except 

those that already controlled

Coal Cleaning –

Thermal Dryer

Low NOx Burner Agreed with CoST recommendation

Comm/Inst Incinerators Selective Non-Catalytic 

Reduction

Both sources are already controlled with 

SNCR

External Combustion 

Boilers, Elec Gen, Solid 

Waste

Selective Non-Catalytic 

Reduction

All 6 sources are already controlled with 

SNCR

Fluid Catalytic Cracking 

Units

Low NOx Burner and Flue 

Gas Recirculation

Nearly all FCCUs are already controlled due 

to the OECA global refinery consent decrees. 

There is one small refinery in West Texas 

that does not appear to be covered by a 

consent decree, so the CoST 

recommendation was accepted.

Glass Manufacturing –

Container, Flat, 

Pressed 

OXY-Firing Disagreed with CoST recommendation. 

OXY-firing is not generally required under 

recent OECA consent decrees. More 

common control is oxygen-enriched air 

staging (OEAS). OXY-firing can only be 

implemented at the time of furnace rebuild, 

which is generally done every 10-15 years. 

Changed recommended control to OEAS 

with a 50% NOx reduction instead of OXYfiring at 85% NOx reduction, except for 

sources that already had NOx controls in 

place due to a consent decree, NSR 

requirement, or state regulation. Assumed 

that a furnace with a NOx emission limit of 

less than 4 lbs/ton of glass pulled was 

already reasonably controlled. 

ICI Boilers –

Coal/Cyclone

Selective Catalytic 

Reduction

Agreed with CoST recommendation of SCR 

except for those sources where a permit or 

state regulation already required the source 

to be controlled. LADCO/OTC also 

recommends SCR

ICI Boilers –

Coal/Stoker

Selective Catalytic 

Reduction

Disagreed with CoST recommendation of 

SCR. CoST has $2200/ton, which appears 
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Source Group CoST Control 

Recommendation

Summary of Recommended Changes to 

CoST Controls and Reductions

very low for ICI boilers. Used LADCO/OTC 

recommendation of SNCR for Coal-Stokers 

with a 50% reduction, except for those 

sources where a permit or state regulation 

already required the source to be controlled.

ICI Boilers – Coal/Wall Low NOx Burner and 

Selective Catalytic 

Reduction

Agreed with CoST recommendation of SCR 

except for those sources where a permit or 

state regulation already required the source 

to be controlled. LADCO/OTC also 

recommends LNB/SCR

ICI Boilers – Gas, 

Natural Gas, Process 

Gas

Selective Catalytic 

Reduction

Disagreed with CoST recommendation of 

SCR. CoST has $3456/ton, which appears 

very low for ICI boilers. Used LADCO/OTC 

recommendation of Low NOx Burners plus 

Flue Gas Recirculation for Gas-fire ICI 

boilers with a 60% reduction, except for 

those sources where a permit or state 

regulation already required the source to be 

controlled

Industrial Incinerators Selective Non-Catalytic 

Reduction

Agreed with CoST recommendation of SNCR 

except for those sources where a permit or 

state regulation already required the source

to be controlled.

Iron & Steel Mills –

Reheating

Low NOx Burner and Flue 

Gas Recirculation

Agreed with CoST recommendation except 

for those sources where a permit or state 

regulation already required the source to be 

controlled.

Municipal Waste 

Combustors

Selective Non-Catalytic 

Reduction

Agreed with CoST recommendation of SNCR 

except for those sources where a permit or 

state regulation already required the source 

to be controlled.

Nitric Acid 

Manufacturing

Nonselective Catalytic 

Reduction

Agreed with CoST recommendation of NSCR 

except for those sources where a permit or 

state regulation already required the source 

to be controlled.

Petroleum Refinery 

Process Heaters

SCR-95% Nearly all refineries are already controlled 

due to the OECA global refinery consent 

decrees, which generally require 40-60% 

reductions across all boilers/heaters that 

each company operates. Not possible at 

present to identify the individual 

boilers/heaters that actually have been 

controlled or are scheduled to be controlled

due to confidentiality agreements between 

EPA and companies.
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Source Group CoST Control 

Recommendation

Summary of Recommended Changes to 

CoST Controls and Reductions

Taconite Ore 

Processing – Induration 

– Coal or Gas

Selective Catalytic 

Reduction

Disagree with CoST recommendation of 

SCR. EPA Region V considers SCR/SNCR 

to be infeasible. Used Low NOx Burners at 

70% reduction instead as reasonable control, 

except for those sources where a permit or 

state regulation already required the source 

to be controlled. .

Utility Boilers* –

Coal/Wall

Selective Catalytic 

Reduction

Agreed with CoST recommendation of SCR 

except for those sources where a permit or 

state regulation already required the source 

to be controlled.

Utility Boilers* – Oil/Gas Selective Catalytic 

Reduction

Agreed with CoST recommendation of SCR 

except for those sources where a permit or 

state regulation already required the source 

to be controlled.

The utility boilers included in the context of this report are non-IPM utility boilers. In the NEI, these units 

have an SCC of 1-01—xxx-xx (the SCC series generally used for electric generating units. However, the 

sources included in this analysis do not sell electricity to the grid. 

Ammonia – NG-fired Reformers

There are 15 sources in this category. The CoST control technology was selective catalytic reduction 

(SCR) with a 90% reduction in NOx emissions. We determined that four of these sources were already 

controlled by either SCR or ultra-NOx burners and recommended no further control/reductions. For all 

other sources, we agreed with the CoST control and emission reduction estimate.

By-Product Coke Mfg; Oven Underfiring

There are 14 sources in this category. The CoST control technology was selective non-catalytic reduction 

(SNCR) with a 60% reduction in NOx emissions. We reviewed a detailed RACT analysis for a facility in 

Pennsylvania that determined that no controls were feasible. For all sources in this category, we 

recommended that no controls were feasible and thus no reductions were appropriate. 

Cement Preheater/Precalciner Kilns

There are 36 sources in this category. The CoST control technology was biosolid injection technology

with a 23% reduction in NOx emissions. We reviewed permits and consent decrees to identify those kilns 

that are already controlled. Several kilns are already controlled based on NOx SIP Call requirements that 

typically required low NOx burners, mid-kiln firing, or an approved alternative that resulted in a 30% 

reduction. Other kilns already had SNCR installed due to a consent decree, new source review 

requirement, or other state-level requirement.
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EPA expressed a concern whether there was sufficient biosolids availability for use by the uncontrolled 

kilns. Also, EPA has done considerable research on cement kiln NOx controls as part of its Industrial 

Sector Integrated Solutions (ISIS) project. EPA uses the ISIS-cement model help analyze policy options 

for various rulemakings. Based on the ISIS work, we recommended that low-NOx burners and SNCR as 

the appropriate control for all types of kilns.

For uncontrolled kilns, we applied a 65% reduction in NOx emissions. For kilns already controlled with 

low-NOx burners or mid-kiln firing, we applied a 35% incremental reduction to account for the additional 

reductions from SNCR. For kilns already controlled with SNCR, we applied no additional emission 

reductions. 

Cement Manufacturing - Dry Process

There are 20 sources in this category. The CoST control technology was SNCR with a 50% reduction in 

NOx emissions. We reviewed permits and consent decrees to identify those kilns that are already 

controlled. Several kilns are already controlled based on NOx SIP Call requirements that typically 

required low NOx burners, mid-kiln firing, or an approved alternative that resulted in a 30% reduction. 

Other kilns already had SNCR installed due to a consent decree, new source review requirement, or other 

state-level requirement.

As discussed earlier, we recommended that low-NOx burners and SNCR as the appropriate control for all 

types of kilns based on the ISIS work. For uncontrolled kilns, we applied a 65% reduction in NOx 

emissions. For kilns already controlled with low-NOx burners or mid-kiln firing, we applied a 35% 

incremental reduction to account for the additional reductions from SNCR. For kilns already controlled 

with SNCR, we applied no additional emission reductions. 

Cement Manufacturing – Wet Process

There are seven sources in this category. The CoST control technology was mid-kiln firing with a 30% 

reduction in NOx emissions. We determined that two of these kilns were installing a pilot SCR system as 

part of a consent decree. One kiln recently went through NSR review and has state-of-the-art control. 

Another kiln is required to install SNCR as part of a consent decree. No additional reductions were 

applied for these kilns. For the remaining kilns, we applied low-NOx burners and SNCR as described in 

the previous sections.

Coal Cleaning – Thermal Dryer

There was one source in this category. The CoST control technology was a low-NOx burner with a 50% 

reduction in NOx emissions. We could not find any information on this source and accepted the CoST 

controls. 
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Comm/Inst Incinerators

There are two sources in this category. The CoST control technology was SNCR with a 45% reduction in 

NOx emissions. Both of these sources are already controlled by SNCR and we applied no additional 

emission reductions.

External Combustion Boilers, Elec Gen, Solid Waste

There are six sources in this category. The CoST control technology was SNCR with a 50% reduction in 

NOx emissions. All six of these sources are already controlled by SNCR and we applied no additional 

emission reductions.

Fluid Catalytic Cracking Units

There are six sources in this category. The CoST control technology was low-NOx burners and flue gas 

recirculation with a 55% reduction in NOx emissions. Nearly all sources are already controlled or 

required to install controls as a result of the EPA’s global refinery consent decrees. There is one small 

refinery in West Texas that does not appear to be covered by a consent decree, so the CoST 

recommendation was accepted.

Glass Manufacturing – Container, Flat, Pressed 

There are 65 sources in this category. The CoST control technology was oxy-firing with an 85% 

reduction in NOx emissions. There were several concerns about using oxy-firing for this analysis. First, 

there is a concern about the timing of installing oxy-firing technology. Oxy-firing is typically installed at 

the time of a furnace rebuild, which is typically done every 10 to 15 years. Second, oxy-firing is not 

generally required under recent EPA consent decrees. More common control is oxygen-enriched air 

staging (OEAS). We recommended that OEAS with a 50% NOx reduction instead of OXY-firing at 85% 

NOx reduction, except for sources that already had NOx controls in place due to a consent decree, NSR 

requirement, or state regulation. We assumed that a furnace with a NOx emission limit of less than 4 

lbs/ton of glass pulled was already reasonably controlled.

ICI Boilers – Coal/Cyclone

There are eight sources in this category. The CoST control technology was SCR with an 80% reduction in 

NOx emissions. We reviewed the Evaluation of Control Options for Industrial, Commercial and 

Institutional (ICI) Boilers Technical Support Document (TSD), March, 2011 prepared by the Lake 

Michigan Air Directors Consortium (LADCO) and the Ozone Transport Commission (OTC). 

LADCO/OTC also recommended SCR for coal-cyclone boilers. Since the LADCO/OTC recommendation 

was consistent with the CoST control, we agreed with the CoST control technology for five sources 

which we determined were uncontrolled. Two sources were determined to be already controlled. One 

source appears to have shut down their coal-fired boilers. No reductions were applied for these three 

sources since they are already controlled. 
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ICI Boilers – Coal/Stoker

There are 45 sources in this category. The CoST control technology was SCR with an 80% reduction in 

NOx emissions. The LADCO/OTC recommendation was for combustion tuning and SNCR. We agreed 

with the LADCO/OTC recommendation and assumed a 50% control efficiency. We determined that most 

of these sources are currently uncontrolled. Two coal-fired boilers are scheduled to be replaced with gasfired boilers. Two other boilers recently installed SNCR. 

ICI Boilers – Coal/Wall

There are 54 sources in this category. The CoST control technology was low-NOx burners and SCR with 

a 91% reduction in NOx emissions. The LADCO/OTC recommendation was also for low-NOx burners 

and SCR. Since the LADCO/OTC recommendation was consistent with the CoST control, we agreed 

with the CoST control technology and emission reductions.

ICI Boilers – Gas, Natural Gas, Process Gas

There are 130 sources in this category. The CoST control technology was SCR with an 80% reduction in 

NOx emissions. The LADCO/OTC recommendation was for low-NOx burners, flue gas recirculation, or 

low-NOx burners combined with flue gas recirculation. We agreed with the LADCO/OTC 

recommendation of low-NOx burners combined with flue gas recirculation and assumed a 60% control 

efficiency. 

Several of these sources are located in the OTR or ozone nonattainment areas, and as a result already have 

a RACT control requirement or emission limitation that is consistent with the LADCO/OTC 

recommendations. A few of these sources are located at petroleum refineries and were assumed to be 

already controlled due to EPA’s refinery enforcement initiative. 

Municipal Waste Combustors

There are 55 sources in this category. The CoST control technology was SNCR with a 45% reduction in 

NOx emissions. We determined that 35 of these sources are already controlled with SNCR and no 

additional reductions were applied. For the remaining uncontrolled sources, we agreed with the CoST 

controls and emission reductions.

Nitric Acid Manufacturing

There are seven sources in this category. The CoST control technology was non-selective catalytic 

reduction (NSCR) with a 98% reduction in NOx emissions. All but one of these sources is already 

controlled by NSCR or SCR. 

Petroleum Refinery Process Heaters

There are 28 sources in this category. The CoST control technology was SCR with a 95% reduction in 

NOx emissions. All of the sources in this category are covered sources under EPA’s global refinery 

enforcement initiative. The settlements generally require 40-60% reductions across all boilers/heaters that 
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each company operates. Companies have submitted NOx compliance plans to OECA that identify the 

specific sources that have been controlled or are planned to be controlled, along with the technology used. 

But it is not possible at present to identify the individual boilers/heaters that actually have been controlled 

or are scheduled to be controlled due to confidentiality agreements between EPA and companies. No 

additional reductions were included for this category.

Taconite Ore Processing – Induration – Coal or Gas

There are 10 sources in this category. The CoST control technology was SCR with a 90% reduction in 

NOx emissions. All of the sources in this category are already subject to Best Available Retrofit 

Technology (BART) requirements under the Regional Haze program. EPA Region V determined that 

BART is low-NOx burners and agreed that SCR controls are infeasible for indurating furnaces. No 

additional reductions were included for this category. 

Utility Boilers – Coal/Wall, Oil, Gas

There are 11 sources in this category. The CoST control technology was SCR with a 80 to 90% reduction 

in NOx emissions depending on fuel type. All of the sources in this category appear to be uncontrolled 

and we agreed with the CoST control and emission reduction estimate.

REVIEW OF CoST RESULTS FOR THE 25 TO 100 TPY GROUP

Due to the large number of sources in this group, we were not able to review individual permits to 

determine whether the individual source was already controlled. Instead, our recommendations were 

based on of state regulations, enforcement actions, engineering judgment, and other available information. 

We generally assumed that sources located in areas with stringent NOx rules are already well controlled 

and we assumed that no additional reductions were likely from these sources. This assumption was 

generally applied in New Jersey, New York and sources located in the Houston nonattainment area. 

Given more time, we would like to have also applied this assumption in other areas with stringent existing 

regulations, such as Chicago, Milwaukee, and Baton Rouge. In any future analysis, it would be useful to 

examine the stringency of rules that apply strictly to nonattainment areas. 

Table 2 summarizes the source categories included in our analysis, the CoST recommendation for NOx 

control, and the recommendation for changing the CoST control measure assignment and associated 

emission reduction estimates. Following Table 2, there is a discussion for each source group to provide 

more detail on the rationale for the recommended changes for each source group. Attachments 5 to 8 are 

tabular comparisons of the initial CoST emission reduction estimates and the recommended changes. All 

Attachments present the results in terms of tons per ozone season, simply estimated by assuming that 
10

ozone season emissions were equal to 5/12 of the annual emissions. Maps 3A and 3B graphically show 

the location of sources and the magnitude of the recommended emission reductions. 

Table 2 – CoST Controls and Recommended Changes for

25 to 100 TPY Sources

Source Group CoST Control 

Recommendation

Summary of Recommended Changes to 

CoST Controls and Reductions

Ammonia – NG-fired 

Reformers

Selective Catalytic 

Reduction

Agreed with CoST recommendation of SCR 

except for those sources where a permit or 

state regulation already required the source to 

be controlled.

Cement Kilns Biosolid Injection 

Technology

Because of low emissions, assume that the 

kiln is already controlled or have very low 

usage which would result in a unreasonably 

high cost-effectiveness

Cement Manufacturing 

– Wet

Mid-kiln Firing Because of low emissions, assume that the 

kiln is already controlled or have very low 

usage which would result in a unreasonably 

high cost-effectiveness

Ceramic Clay Mfg; 

Drying

Low NOx Burner Questions about technical feasibility for these 

category, assume zero reductions

Coal Cleaning –

Thermal Dryer

Low NOx Burner Agree with CoST recommendation

Comm/Inst Incinerators Selective Non-Catalytic 

Reduction

Agree with CoST recommendation

External Combustion 

Boilers, Elec Gen, 

Sub/Bit Coal

Selective Non-Catalytic 

Reduction

Agree with CoST recommendation, although 

questions as to whether the source is already 

controlled or very low usage which would 

result in a unreasonably high costeffectiveness

Fluid Catalytic Cracking 

Units

Low NOx Burner and Flue 

Gas Recirculation

Nearly all FCCUs are already controlled due 

to the OECA global refinery consent decrees.

Gas Turbines Low NOx Burners Agreed with CoST recommendation except for 

those sources where a state regulation 

already required the source to be controlled.

Glass Manufacturing –

Container, Flat, Pressed 

OXY-Firing Because of low emissions, assume that the 

furnace is already controlled or have very low 

usage which would result in a unreasonably 

high cost-effectiveness

ICI Boilers –

Coal/Stoker

Selective Catalytic 

Reduction

Disagreed with CoST recommendation of 

SCR. CoST has $2200/ton, which appears 

very low for ICI boilers. Used LADCO/OTC 

recommendation of SNCR for Coal-Stokers 

with a 50% reduction, except for those 

sources where a state regulation already 

required the source to be controlled.

ICI Boilers – Coal/Wall Low NOx Burner and 

Selective Catalytic 

Reduction

Agreed with CoST recommendation of SCR 

except for those sources where a state 

regulation already required the source to be 
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Source Group CoST Control 

Recommendation

Summary of Recommended Changes to 

CoST Controls and Reductions

controlled. LADCO/OTC also recommends 

LNB/SCR

ICI Boilers – Distillate 

Oil or Process Gas

Selective Catalytic 

Reduction

Because of low emissions, assume that the 

boiler is already controlled or have very low 

usage which would result in a unreasonably 

high cost-effectiveness

ICI Boilers – Natural 

Gas

Low NOx Burner and 

Selective Catalytic 

Reduction

Disagreed with CoST recommendation of 

SCR. Used LADCO/OTC recommendation of 

Low NOx Burners plus Flue Gas Recirculation 

for Gas-fire ICI boilers with a 60% reduction, 

except for those sources where a permit or 

state regulation already required the source to 

be controlled

ICI Boilers – Residual 

Oil 

Low NOx Burner and 

Selective Non-Catalytic 

Reduction

Agreed with CoST recommendation of SCR 

except for those sources where a state 

regulation already required the source to be 

controlled.

Industrial Incinerators Selective Non-Catalytic 

Reduction

Agreed with CoST recommendation of SNCR 

except for those sources where a state 

regulation already required the source to be 

controlled.

Iron & Steel Mills –

Reheating

Low NOx Burner and Flue 

Gas Recirculation

Agreed with CoST recommendation except for 

those sources where a state regulation 

already required the source to be controlled.

Municipal Waste 

Combustors

Selective Non-Catalytic 

Reduction

Agreed with CoST recommendation of SNCR 

except for those sources where a state 

regulation already required the source to be 

controlled.

Nitric Acid 

Manufacturing

Nonselective Catalytic 

Reduction

Agreed with CoST recommendation of NSCR 

except for those sources where a state 

regulation already required the source to be 

controlled.

Petroleum Refinery 

Process Heaters

SCR or Ultra-Low NOx 

Burner

Nearly all refineries are already controlled due 

to the OECA global refinery consent decrees, 

which generally require 40-60% reductions 

across all boilers/heaters that each company 

operates. Not possible at present to identify 

the individual boilers/heaters that actually 

have been controlled or are scheduled to be 

control due to confidentiality agreements 

between EPA and companies.

Utility Boilers –

Coal/Wall

Selective Catalytic 

Reduction

Agreed with CoST recommendation of SCR 

except for those sources where a state 

regulation already required the source to be 

controlled

Utility Boilers – Oil/Gas Selective Catalytic 

Reduction

Because of low emissions, assume 

unreasonably high cost-effectiveness for 

SCR; use LNB/FGR as reasonable control.
12

Ammonia – NG-fired Reformers

There are seven sources in this category. The CoST control technology was SCR with a 90% reduction in 

NOx emissions. For all other sources, we agreed with the CoST control and emission reduction estimate.

Cement Kilns

There are six sources in this category. The CoST control technology was either biosolid injection 

technology with a 23% reduction in NOx emissions or mid-kiln firing with a 30% reduction. Because of 

the low baseline emissions for these kilns, we assumed that the kilns were already controlled or have low 

usage which would result in a very high cost-effectiveness. We determined that no reductions be applied 

for these sources. 

Coal Cleaning – Thermal Dryer

There are 10 sources in this category. The CoST control technology was a low-NOx burner with a 50% 

reduction in NOx emissions. We agreed with the CoST control and emission reduction estimate.

Commercial/Institutional Incinerators

There are four sources in this category. The CoST control technology was SNCR with a 45% reduction in 

NOx emissions. We agreed with the CoST control and emission reduction estimate.

External Combustion Boilers, Electric Generation, Coal

There are 14 sources in this category. The CoST control technology was SNCR with a 40% reduction in 

NOx emissions. It appears that the sources in this category are low usage spreader stokers. Although there 

may be a concern about the cost-effectiveness for these sources, we agreed with the CoST control and 

emission reduction estimate.

Fluid Catalytic Cracking Units

There are 21 sources in this category. The CoST control technology was low-NOx burners and flue gas 

recirculation with a 55% reduction in NOx emissions. All sources in this category are assumed subject to 

existing control requirements resulting from the OECA global refinery enforcement initiative. 

Additionally, eight of the sources are located in the Houston nonattainment area and are likely subject to 

stringent controls. For these reasons, we assumed no further control or emission reductions for the 

FCCUs. 

Gas Turbines

There are 438 sources in this category. The CoST control technology was for low-NOx burners with a 

68% reduction in NOx emissions. We agreed with the CoST control and emission reduction estimate, 

except for those sources located in the OTR and Houston ozone nonattainment area, where we assumed 

that these sources already had RACT controls.

Glass Manufacturing – Container, Flat, Pressed 
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There are eight sources in this category. The CoST control technology was SCR with a 90% reduction in 

NOx emissions. Because of the low baseline emissions for these furnaces, we assumed that the furnaces 

were already controlled and determined that no reductions be applied for these sources. 

ICI Boilers – Coal/Stoker

There are 133 sources in this category. The CoST control technology was SCR with a 90% reduction in 

NOx emissions. The LADCO/OTC recommendation was for combustion tuning and SNCR. We agreed 

with the LADCO/OTC recommendation and assumed a 50% control efficiency.

ICI Boilers – Coal/Wall

There are 11 sources in this category. The CoST control technology was SCR with a 90% reduction in 

NOx emissions. The CoST control technology was low-NOx burners and SCR with a 91% reduction in 

NOx emissions. The LADCO/OTC recommendation was also for low-NOx burners and SCR. Since the 

LADCO/OTC recommendation was consistent with the CoST control, we agreed with the CoST control 

technology and emission reductions.

ICI Boilers – Natural Gas

There are 376 sources in this category. The CoST control technology was low-NOx burners and SCR 

with a 91% reduction in NOx emissions. The LADCO/OTC recommendation was for low-NOx burners, 

flue gas recirculation, or low-NOx burners combined with flue gas recirculation. We agreed with the 

LADCO/OTC recommendation of low-NOx burners combined with flue gas recirculation and assumed a 

50% control efficiency, except for those sources located in the OTR and Houston ozone nonattainment 

area, where we assumed that these sources already had RACT controls.

ICI Boilers – Process Gas

There are 57 sources in this category. The CoST control technology was SCR with a 90% reduction in 

NOx emissions. Most of these sources are located at petroleum refineries and are assumed subject to 

existing control requirements resulting from the OECA global refinery enforcement initiative, or are 

located in the Houston nonattainment area and are likely subject to stringent controls. For these reasons, 

we assumed no further control or emission reductions.

ICI Boilers – Residual Oil 

There are 28 sources in this category. The CoST control technology was low-NOx burner and SNCR with 

a 69.5% reduction in NOx emissions. We agreed with the CoST control and emission reduction estimate, 

except for those sources located in the OTR and Houston ozone nonattainment area, where we assumed 

that these sources already had RACT controls.

Industrial Incinerators

There are 21 sources in this category. The CoST control technology was SNCR with a 45% reduction in 

NOx emissions. We agreed with the CoST control and emission reduction estimate, except for those 
14

sources located in the OTR and Houston ozone nonattainment area, where we assumed that these sources 

already had RACT controls.

Iron & Steel Mills – Reheating

There are 32 sources in this category. The CoST control technology was low-NOx burners and flue gas 

recirculation with a 77% reduction in NOx emissions. We agreed with the CoST control and emission 

reduction estimate.

Municipal Waste Combustors

There are 25 sources in this category. The CoST control technology was SCR with a 90% reduction in 

NOx emissions. RTI identified the sources are already controlled and no additional reductions were 

applied for these sources. For the remaining sources, we agreed with the CoST controls and emission 

reductions.

Nitric Acid Manufacturing

There are 14 sources in this category. The CoST control technology was NSCR with a 98% reduction in 

NOx emissions. We agreed with the CoST control and emission reduction estimate. 

Petroleum Refinery Process Heaters

There are 30 sources in this category. The CoST control technology was SCR with a 90-98% reduction or 

ultra-low NOx burners with a 30-50% reductions in NOx emissions. Most of these sources are located at 

petroleum refineries and are assumed subject to existing control requirements resulting from the OECA 

global refinery enforcement initiative, or are located in the Houston nonattainment area and are likely 

subject to stringent controls. For these reasons, we assumed no further control or emission reductions.

Utility Boilers – Coal/Wall

There are three sources in this category. The CoST control technology was SCR with a 90% reduction in 

NOx emissions. We agreed with the CoST control and emission reduction estimate.

Utility Boilers – Oil/Gas

There are 27 sources in this category. The CoST control technology was SCR with a 80% reduction in 

NOx emissions. The LADCO/OTC recommendation was for low-NOx burners or flue gas recirculation. 

We agreed with the LADCO/OTC recommendation of low-NOx burners combined with flue gas 

recirculation and assumed a 60% control efficiency.
15

Attachment 1 – NOx Emission Reductions by State for Sources in the > 100 Ton per Year Reduction Group

State

Number of 

Sources

NOx emissions 

reduced from 

controls in CoST 

(tons/O3 season) 

 ( A )

Recommended

NOx emissions 

reduced from 

controls in CoST 

(tons/O3 season) 

 ( B )

Size of correction

in NOx emission 

reductions 

(tons/O3 season) 

 ( A - B )

Alabama 24 2,855 2,287 568

Arkansas 6 455 293 162

Delaware 2 206 0 206

Florida 20 2,158 1,370 788

Illinois 21 2,659 1,472 1,187

Indiana 41 5,405 4,510 896

Iowa 10 1,226 999 227

Kansas 7 735 452 283

Kentucky 11 915 838 77

Louisiana 57 7,623 3,622 4,000

Maryland 10 1,933 355 1,578

Michigan 27 2,758 1,768 990

Mississippi 7 1,054 516 538

Missouri 15 1,698 1,562 136

New Jersey 15 417 0 417

New York 30 3,091 281 2,810

Ohio 37 4,098 2,039 2,058

Oklahoma 20 2,949 1,864 1,086

Pennsylvania 52 5,637 2,215 3,422

Tennessee 13 4,741 1,987 2,755

Texas 65 8,860 6,383 2,477

Virginia 28 3,337 3,033 303

West Virginia 9 1,180 793 387

Wisconsin 20 4,092 3,416 676

547 70,082 42,054 28,028
16

Attachment 2 – NOx Emission Reductions by Source Group for Sources in the > 100 Ton per Year Reduction Group

Source Group

Number of 

Sources

NOx emissions 

reduced from 

controls in CoST 

(tons/O3 season) 

 ( A )

Recommended

NOx emissions 

reduced from 

controls in CoST 

(tons/O3 season) 

 ( B )

Size of correction

in NOx emission 

reductions 

(tons/O3 season) 

 ( A - B )

Ammonia - NG-Fired Reformers 15 2,427 1,551 875

By-Product Coke Mfg; Oven Underfiring 14 1,199 0 1,199

Cement Kilns 36 3,932 6,586 -2,654

Cement Manufacturing - Dry 20 3,672 2,234 1,438

Cement Manufacturing - Wet 7 1,294 1,120 174

Coal Cleaning-Thrml Dryer; Fluidized Bed 1 50 50 0

Comm./Inst. Incinerators 2 137 0 137

External Combustion Boilers, Solid Waste 6 472 0 472

Fluid Cat Cracking Units; Cracking Unit 6 607 52 556

Fuel Fired Equip; Process Htrs; Pro Gas 2 143 143 0

Glass Manufacturing - Container 34 2,759 678 2,081

Glass Manufacturing – Flat 23 10,241 6,024 4,217

Glass Manufacturing - Pressed 8 684 402 282

ICI Boilers - Coal/Cyclone 8 2,987 1,840 1,147

ICI Boilers - Coal/FBC 3 233 180 53

ICI Boilers - Coal/Stoker 45 4,688 2,938 1,750

ICI Boilers - Coal/Wall 54 12,041 7,996 4,045

ICI Boilers – Gas 10 1,266 910 356

ICI Boilers - Natural Gas 84 7,578 3,452 4,126

ICI Boilers - Process Gas 36 3,868 1,229 2,639

ICI Boilers - Residual Oil 2 199 82 117

Indust. Incinerators 9 586 124 461

In-Proc;Process Gas;Coke Oven/Blast Furn 3 299 0 299
17

Source Group

Number of 

Sources

NOx emissions 

reduced from 

controls in CoST 

(tons/O3 season) 

 ( A )

Recommended

NOx emissions 

reduced from 

controls in CoST 

(tons/O3 season) 

 ( B )

Size of correction

in NOx emission 

reductions 

(tons/O3 season) 

 ( A - B )

In-Process; Bituminous Coal; Cement Kiln 2 290 295 -5

Iron & Steel - In-Process Coal Combustion 4 419 0 419

Iron & Steel Mills – Reheating 2 156 156 0

Municipal Waste Combustors 55 1,591 876 715

Nitric Acid Manufacturing 7 687 82 605

Petroleum Refinery Gas-Fired Process Heaters 28 2,025 0 2,025

Taconite Iron Ore - Induration - Coal or Gas 10 829 451 379

Utility Boiler - Coal/Wall 5 555 555 0

Utility Boiler - Oil-Gas/Tangential 2 526 526 0

Utility Boiler - Oil-Gas/Wall 4 1,645 1,524 121

547 70,082 42,054 28,028
18

Attachment 3 – NOx Emission Reductions by 3-Digit NAICS Code for Sources in the > 100 Ton per Year Reduction Group

3-Digit NAICS Code

Number of 

Sources

NOx emissions 

reduced from 

controls in CoST 

(tons/O3 season) 

 ( A )

Recommended

NOx emissions 

reduced from 

controls in CoST 

(tons/O3 season) 

 ( B )

Size of correction

in NOx emission 

reductions 

(tons/O3 season) 

 ( A - B )

211 Oil and Gas Extraction 1 46 30 16

212 Mining (except Oil and Gas) 11 879 500 379

221 Utilities 10 1,186 853 333

311 Food Mfg 12 1,181 815 366

312 Beverage and Tobacco Product Mfg 7 761 761 0

322 Paper Mfg 70 11,616 7,968 3,648

324 Petroleum and Coal Products Mfg 49 3,942 239 3,703

325 Chemical Mfg 132 19,689 10,753 8,937

3272 Glass and Glass Product Mfg 64 13,588 7,047 6,540

3273 Cement and Concrete Product Mfg 64 9,113 10,183 -1,070

3274 Lime & Gypsum Product Mfg 1 75 52 22

331 Primary Metal Mfg 50 4,908 1,837 3,070

333 Machinery Mfg 1 57 35 21

336 Transportation Equipment Mfg 2 148 103 46

424 Merchant Wholesalers, Nondurable Goods 2 160 0 160

531 Real Estate 1 72 0 72

562 Waste Mgmt and Remediation Services 65 2,366 843 1,523

611 Educational Services 5 295 34 261

547 70,082 42,054 28,028
19

Attachment 4 – NOx Emission Reductions by 3-Digit NAICS Code for Sources in the > 100 Ton per Year Reduction Group

Recommended Change to CoST Control

Number of 

Sources

NOx emissions 

reduced from 

controls in CoST 

(tons/O3 season) 

 ( A )

Recommended

NOx emissions 

reduced from 

controls in CoST 

(tons/O3 season) 

 ( B )

Size of correction

in NOx emission 

reductions 

(tons/O3 season) 

 ( A - B )

Already Controlled 138 12,973 0 12,973

Already Controlled by Glass CD 12 1,034 0 1,034

Already Controlled By Refinery CD 52 4,300 0 4,300

Control Technically or Economically Infeasible 18 1,618 0 1,618

Fuel Switch Already Occurred 4 2,370 0 2,370

Low NOx Burner 7 629 500 129

Low NOx Burner and Flue Gas Recirculation 88 8,792 6,022 2,769

Low NOx Burner and SCR 44 7,996 7,996 0

Low NOx Burner and SNCR 41 5,895 10,236 -4,341

Non-Selective Catalytic Reduction 1 82 82 0

Oxygen Enriched Air Staging 47 12,077 7,104 4,973

Selective Catalytic Reduction (SCR) 27 6,088 6,088 0

Selective Non-Catalytic Reduction (SNCR) 62 5,109 4,026 1,083

Source Already Shutdown 6 1,120 0 1,120

547 70,082 42,054 28,028 
20

Attachment 5 – NOx Emission Reductions by State for Sources in the 25 to 100 Ton per Year Reduction Group

State

Number of 

Sources

NOx emissions 

reduced from 

controls in CoST 

(tons/O3 season) 

 ( A )

Recommended

NOx emissions 

reduced from 

controls in CoST 

(tons/O3 season) 

 ( B )

Size of correction

in NOx emission 

reductions 

(tons/O3 season) 

 ( A - B )

Alabama 38 641 517 123

Arkansas 14 277 203 74

Delaware 5 73 58 15

Florida 27 532 399 133

Illinois 91 1,519 845 675

Indiana 44 894 580 314

Iowa 19 422 309 113

Kansas 31 562 421 140

Kentucky 33 619 407 212

Louisiana 101 2,046 1,467 579

Maryland 18 353 209 144

Michigan 67 1,149 844 304

Mississippi 22 366 343 23

Missouri 13 224 179 45

New Jersey 7 72 11 61

New York 41 685 59 625

Ohio 86 1,476 1,075 402

Oklahoma 40 749 669 81

Pennsylvania 79 1,359 423 936

Tennessee 42 742 514 228

Texas 374 6,444 3,311 3,133

Virginia 30 450 350 100

West Virginia 21 421 334 87

Wisconsin 37 697 471 226

1280 22,774 14,000 8,774
21

Attachment 6 – NOx Emission Reductions by Source Group for Sources in the 25 to 100 Ton per Year Reduction Group

Source Group

Number of 

Sources

NOx emissions 

reduced from 

controls in CoST 

(tons/O3 season) 

 ( A )

Recommended

NOx emissions 

reduced from 

controls in CoST 

(tons/O3 season) 

 ( B )

Size of correction

in NOx emission 

reductions 

(tons/O3 season) 

 ( A - B )

Ammonia - NG-Fired Reformers2 7 200 155 45

Cement Kilns 4 93 0 93

Cement Manufacturing - Wet 2 60 0 60

Ceramic Clay Mfg; Drying 4 29 0 29

Coal Cleaning-Thrml Dryer; Fluidized Bed 10 188 188 0

Comm./Inst. Incinerators 4 47 47 0

Ext Comb Boilers, Elec Gen, Nat Gas (2) 1 28 28 0

Ext Comb Boilers, Elec Gen, Sub/Bit Coal (3) 14 158 158 0

Fbrglass Mfg; Txtle-Type Fbr; Recup Furn 2 9 9 0

Fluid Cat Cracking Units; Cracking Unit 21 393 0 393

Fuel Fired Equip; Furnaces; Natural Gas 3 18 18 0

Fuel Fired Equip; Process Htrs; Pro Gas 7 86 86 0

Gas Turbines - Natural Gas 438 7,193 5,749 1,444

Glass Manufacturing - Flat 8 190 0 190

ICI Boilers - Coal/FBC 1 35 22 13

ICI Boilers - Coal/Stoker 133 2,502 1,629 873

ICI Boilers - Coal/Wall 11 246 246 0

ICI Boilers - Distillate Oil 4 75 0 75

ICI Boilers - Gas 26 601 0 601

ICI Boilers - Natural Gas 350 6,814 3,705 3,109

ICI Boilers - Oil 2 41 0 41

ICI Boilers - Process Gas 31 609 0 609

ICI Boilers - Residual Oil 28 484 437 47
22

Source Group

Number of 

Sources

NOx emissions 

reduced from 

controls in CoST 

(tons/O3 season) 

 ( A )

Recommended

NOx emissions 

reduced from 

controls in CoST 

(tons/O3 season) 

 ( B )

Size of correction

in NOx emission 

reductions 

(tons/O3 season) 

 ( A - B )

Indust. Incinerators 21 230 118 113

In-Proc;Process Gas;Coke Oven/Blast Furn 4 33 8 25

Iron & Steel - In-Process Comb - Coal 1 19 0 19

Iron & Steel Mills - Reheating 32 481 481 0

Municipal Waste Combustors 25 472 228 243

Nitric Acid Manufacturing 14 363 289 74

Petroleum Refinery Gas-Fired Process Heaters 30 456 0 456

Solid Waste Disp;Gov;Other Incin;Sludge 1 6 6 0

Space Heaters - Natural Gas 2 17 13 4

Steel Foundries; Heat Treating Furn 7 122 122 0

Surf Coat Oper;Coating Oven Htr;Nat Gas 2 11 0 11

Utility Boiler - Coal/Wall 2 48 48 0

Utility Boiler - Coal/Wall2 1 13 13 0

Utility Boiler - Oil-Gas/Tangential 8 99 62 37

Utility Boiler - Oil-Gas/Wall 19 307 137 170

1280 22,774 14,000 8,774
23

Attachment 7 – NOx Emission Reductions by 3-Digit NAICS Code for Sources in the 25 to 100 Ton per Year Reduction Group

3-Digit NAICS Code

Number of 

Sources

NOx emissions 

reduced from 

controls in CoST 

(tons/O3 season) 

 ( A )

Recommended

NOx emissions 

reduced from 

controls in CoST 

(tons/O3 season) 

 ( B )

Size of correction

in NOx emission 

reductions 

(tons/O3 season) 

 ( A - B )

211 Oil and Gas Extraction 146 2,674 2,573 100

212 Mining (except Oil and Gas) 12 247 227 20

213 Support Activities for Mining 1 20 20 0

221 Utilities 96 1,575 1,035 540

311 Food Manufacturing 46 715 450 266

312 Beverage and Tobacco Products 9 151 91 60

313 Textile Mills 1 24 15 9

314 Textile Product Mills 1 12 7 4

316 Leather and Allied Product Manufacturing 1 10 7 3

321 Wood Product Manufacturing 6 100 56 44

322 Paper Manufacturing 79 1,662 1,028 634

324 Petroleum and Coal Products 115 2,083 527 1,556

325 Chemical Manufacturing 332 6,480 3,218 3,262

326 Plastics and Rubber Products 13 206 142 65

327 Nonmetallic Mineral Product Manufacturing 24 417 32 385

331 Primary Metal Manufacturing 87 1,380 1,094 285

332 Fabricated Metal Product Manufacturing 4 80 46 33

333 Machinery Manufacturing 2 20 14 6

334 Computer and Electronic Products 1 9 9 0

336 Transportation Equipment Manufacturing 13 261 192 69

337 Furniture and Related Products 2 18 18 0

447 Gasoline Stations 1 7 0 7

454 Nonstore Retailers 1 9 0 9
24

3-Digit NAICS Code

Number of 

Sources

NOx emissions 

reduced from 

controls in CoST 

(tons/O3 season) 

 ( A )

Recommended

NOx emissions 

reduced from 

controls in CoST 

(tons/O3 season) 

 ( B )

Size of correction

in NOx emission 

reductions 

(tons/O3 season) 

 ( A - B )

482 Rail Transportation 3 37 23 14

486 Pipeline Transportation 156 2,551 2,034 517

488 Support Activities for Transportation 1 18 12 6

531 Real Estate 8 147 0 147

541 Professional Services 6 81 77 4

561 Administrative and Support Services 1 8 0 8

562 Waste Mgmt and Remediation Services 21 376 184 192

611 Educational Services 62 963 617 346

622 Hospitals 7 116 36 80

713 Amusement, Gambling, and Recreation 2 49 45 4

721 Accommodation 2 25 10 15

922 Justice, Public Order, and Safety Activities 4 29 17 12

923 Administration of Human Resources 1 12 8 4

928 National Security and International Affairs 13 201 135 66

1280 22,774 14,000 8,774
25

Attachment 8 – NOx Emission Reductions by 3-Digit NAICS Code for Sources in the 25 to 100 Ton per Year Reduction Group

Recommended Change to CoST Control

Number of 

Sources

NOx emissions 

reduced from 

controls in CoST 

(tons/O3 season) 

 ( A )

Recommended

NOx emissions 

reduced from 

controls in CoST 

(tons/O3 season) 

 ( B )

Size of correction

in NOx emission 

reductions 

(tons/O3 season) 

 ( A - B )

Already Controlled 207 3,380 0 3,380

Already Controlled by Refinery CD 40 704 0 704

Low NOx Burner 362 6,087 6,087 0

Low NOx Burner and Flue Gas Recirculation 361 6,726 4,491 2,235

Low NOx Burner and SCR 11 246 246 0

Low NOx Burner and SNCR 24 437 437 0

Natural Gas Reburn 1 28 28 0

Non-Selective Catalytic Reduction 12 289 289 0

Questions About Feasibility 1 22 0 22

Questions About Feasibility - Cement 6 154 0 154

Questions About Feasibility - Ceramic Clay Mfg 4 29 0 29

Questions about Feasibility - Coating Ovens 2 11 0 11

Questions about Feasibility - Distillate Oil 6 116 0 116

Questions About Feasibility - Glass 7 167 0 167

Questions about Feasibility - Process Gas 50 1,070 0 1,070

Selective Catalytic Reduction 8 216 216 0

Selective Non-Catalytic Reduction 178 3,094 2,207 886

1280 22,774 14,000 8,774