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MEMORANDUM

TO: Toni Jones, U.S. Environmental Protection Agency

FROM: Eastern Research Group, Inc.

DATE: November 26, 2012

SUBJECT: Summary of the Secondary Impacts of Control Options for CISWI Standards

1.0 PURPOSE

This memorandum summarizes the secondary impacts associated with control devices used to 

comply with the final emission standards for Commercial and Industrial Solid Waste Incineration 

(CISWI) units. Secondary impacts result from the consumption of fuel, water, and electricity 

and generation of solid wastes by control devices. Section 2.0 provides a background for the 

standards, Section 3.0 presents the secondary impact estimates associated with control devices 

necessary for all units to comply with the standards, and Section 4.0 presents the air emission 

estimates associated with the secondary impacts. Section 5.0 discusses secondary impacts 

resulting from new source compliance with CISWI standards.

2.0 BACKGROUND

The U.S. Environmental Protection Agency (EPA), under section 129 of the Clean Air Act 

(CAA), is required to regulate emissions of the following nine pollutants from Commercial and 

Industrial Solid Waste Incineration (CISWI) units: hydrogen chloride (HCl), carbon monoxide 

(CO), lead (Pb), cadmium (Cd), mercury (Hg), particulate matter (PM), dioxins/furans 

(PCDD/PCDF), nitrogen oxides (NOx), and sulfur dioxide (SO2). 

On December 1, 2000, EPA established new source performance standards and emission 

guidelines for CISWI units under Sections 111 and 129 of the CAA. In 2001, EPA was granted 

a petition for reconsideration regarding the definitions of “commercial and industrial waste” and 

“commercial and industrial solid waste incineration unit.” Also in 2001, the United States Court 

of Appeals for the District of Columbia Circuit granted EPA’s voluntary remand, without 

vacatur, of the 2000 rule. In 2005, EPA proposed and finalized the CISWI definition rule which 

revised the definitions of “solid waste,” “commercial and industrial waste,” and “commercial and 

industrial waste incineration unit.” In 2007, the United States Court of Appeals for the District 

of Columbia Circuit vacated and remanded the 2005 commercial and industrial solid waste 

incineration definition rule.

In response to the voluntary remand that was granted in 2001, the vacatur, and remand of the 

CISWI definition rule in 2007, EPA developed these final standards for CISWI units. On March 

21, 2011, the EPA promulgated revised NSPS and EG as its response to the voluntary remand 

that was granted in 2001 and the vacatur and remand of the commercial and industrial solid 

waste incineration definition rule in 2007. In addition, the standards re-development included 

the 5-year technology review of the new source performance standards and emission guidelines 

required under Section 129. Following that action, the Administrator received petition[s] for 

reconsideration and identified some issues that warranted further opportunity for public 
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comment. In addition, data were received that enabled the EPA to revise the CISWI inventory of 

waste-burning kilns and energy recovery units to more accurately reflect the definition of nonhazardous secondary materials. On December 23, 2011, the EPA published proposed 

amendments that incorporated these changes and allowed public comment on specific issues 

identified for reconsideration. In addition, these final standards include the 5-year technology 

review of the new source performance standards and emission guidelines required under Section 

129 of the CAA. The EPA has developed a series of maximum achievable control technology 

(MACT) floor and beyond the MACT floor (BTF) options for consideration in developing the 

final standards. The development of the final emission limits used to determine these options is 

discussed in more detail in a separate memorandum.1 

3.0 SUMMARY OF SECONDARY IMPACT ESTIMATES 

To comply with the final standards, facilities may need to install the following types of controls 

on CISWI units:

• Wet scrubbers (WS) to reduce HCl and SO2 emissions, 

• Fabric filters (FF) to reduce Cd, Pb, and PM emissions,

• Duct sorbent injection/fabric filter (DIFF) systems to reduce HCl and SO2 emissions,

• Regenerative Thermal Oxidizers (RTO) to reduce CO emissions,

• Selective non-catalytic reduction (SNCR) to reduce NOx emissions,

• Activated carbon injection (ACI) systems to reduce PCDD/PCDF and Hg emissions, and

• Afterburner retrofits, tune-ups, or oxidation catalysts to reduce CO emissions.

Additional electricity is required to operate the pumps and fans associated with wet scrubbers, 

FF, DIFF, and SNCR systems. Also, water and subsequent wastewater disposal are required to 

operate wet scrubbers, DIFF and SNCR systems. Activated carbon injection systems require 

activated carbon as well as a method to dispose of the dust produced from the ACI system. 

Likewise, DIFF systems generate dust which must be disposed of. RTOs require natural gas to 

oxidize the carbon monoxide in the flue gas. Although afterburners require natural gas to 

operate, these are primarily replacing existing afterburners, so the change in natural gas 

consumption may be minimal, and we do not have the data to be able to estimate this change.

The algorithms used in the cost analysis provide annual cost estimates for electricity, water, and 

carbon requirements as itemized components of the annual costs for the control device.2 These 

cost elements for the control devices anticipated to be installed to comply with the final 

standards were then summed up to provide an estimate of the overall costs of electricity, water 

and activated carbon. To estimate the secondary impact components (e.g., electricity, water, and 

dust from carbon), the itemized annual cost of each component was divided by the unit price of 

the component utilized by the algorithm. To estimate the additional annual fuel requirements for 

each combustion unit operating an RTO, the annual operating hours were multiplied by the 

natural gas fuel requirement. The increased dust collected by improvements made to existing FF 

systems were estimated based on the PM reduction required to meet the emission limit.

Two control scenarios were considered for the final standards: 

• Compliance by additional control only, and

• Compliance or choose another method of disposal, depending on which cost was lowest.

These scenarios are described in sections 3.1 and 3.2, respectively. 
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3.1 Compliance by Additional Control Only

In the first scenario, each CISWI unit in all subcategories complies with the final MACT floor 

standards by installing the anticipated control devices and associated monitoring equipment. 

Table 3-1 shows the estimated values for secondary impacts, by subcategory, for the “All units 

comply” scenario.

TABLE 3-1. Secondary Impacts for MACT Compliance 

All units comply

Subcategory

Electricity 

Required 

(MWh/yr)

Water Required 

(gal/yr)

Activated 

Carbon 

Required 

(ton/yr)

Dust 

Produced 

(ton/yr)

Supplemental 

Fuel 

Requirements 

(MMft3/yr)

ERU - Liquid/Gas 5,637 21,303,000 0 308 -

ERU - Solids 146,733 70,803,115,725 3,355 13,566 -

Incinerators 7,731 102,582,724 236 342 -

Small, remote 302 0 10 21 -

Kilns 64,542 528,609,726 10,291 11,486 1,444

Totals 224,946 71,455,611,175 13,891 25,724 1,444

3.2 Compliance or Alternative Method of Disposal

The second scenario entails a situation where facilities considered alternative disposal options 

and, where the alternative disposal methods are less expensive than adding control devices to 

comply with the standards, would instead cease burning waste and use alternative disposal 

methods. In addition to the electricity, water, and activated carbon requirements for those 

facilities that choose to add control devices to comply with the standards, secondary impacts also 

occur when alternative waste-handling methods are used. For the majority of incinerators, it 

would be less expensive to send waste to a landfill than to comply with the final emission limits 

(i.e., facilities would choose to shut down CISWI units). According to our estimates based on 

unit capacities and annual operating hours, this would result in approximately 110,567 tons per 

year of additional waste being sent to landfills. This would also result in subsequent landfill gas 

emissions from decomposition of this waste, which would likely be sent to a landfill gas flare. 

This gas flaring would result in emissions of NOx and CO, with some SO2, PM, and small 

amounts of mercury also being emitted. Details on landfill emissions can be found in Appendix 

C of the CISWI emission reductions memorandum.

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 For small, remote units, it was determined 

that it is generally less expensive for facilities to segregate their waste and divert the nonferrous metal 

and chlorinated plastic to a landfill than to landfill all of their waste. In this case, the landfilled material is 

considered non-digestable and will not contribute significantly to landfill emissions. While not 

quantified in our analysis, there are also likely to be secondary emissions associated with the 

transport of the waste to a landfill site. These emissions would be site-specific and depend 

primarily on the number of trips, type of vehicle, and distance traveled necessary to transport the 

waste to the landfill. 
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Table 3-2 shows the estimated values for secondary impacts resulting from each facility 

choosing the lowest-cost option for its units. Details regarding the unit-specific, lowest-cost 

options can be found in the compliance cost memorandum.2

TABLE 3-2. Secondary Impacts for MACT Compliance for Lowest Cost Options

Lowest Cost Option

Subcategory

Electricity 

Required 

(MWh/yr)

Water 

Required 

(gal/yr)

Activated 

Carbon 

Required 

(ton/yr)

Dust 

Produced 

(ton/yr)

Supplemental 

Fuel 

Requirements 

(Million ft3/yr)

Annual Waste 

Diverted to 

Landfill 

(ton/yr)

ERU - Liquid/Gas 5,637 21,303,000 0 308 -

ERU - Solids 146,733 70,803,115,725 3,355 13,566 -

Incinerators 494 8,178 67 68 - 110,567

Small, remote 23 0 1 2 -

Kilns 64,542 528,609,726 10,291 11,486 1,444

Totals 217,429 71,353,036,629 13,714 25,431 1,444 110,567

4.0 SUMMARY OF SECONDARY IMPACT EMISSION ESTIMATES

Emission factors from EPA’s eGRID4 database were used to calculate emissions resulting from 

the electricity required for additional control devices, and emission factors from EPA’s AP-42 

emission factor document5 were used to calculate emissions resulting from the combustion of 

additional fuel for RTOs. Increased electrical use from the control options will require 

additional fuel to be burned in power plants, resulting in emissions of CO2 and criteria pollutants, 

such as SO2, NOx, and CO. Emissions of these pollutants (caused by increase in electricity) were 

estimated using EPA’s eGRID database.4 The eGRID database summarizes emissions of criteria 

pollutants on a per electrical usage basis (lb emitted per MW-hr), on a national average or state 

average basis. For this analysis the national average was used. To estimate emissions from 

combustion of natural gas, emission factors from EPA’s AP-42 emission factor document were 

used.5

 

Tables 4-1 summarizes the resulting emissions of CO2, CO, NOx, and SO2 from combustion of 

natural gas supplemental fuel and increase electricity usage for the control options analyzed for 

existing sources. Table 4-2 shows the resulting emissions of CO2, CO, NOx, and SO2 from 

combustion of natural gas supplemental fuel and increase electricity usage for the lowest cost 

options analyzed for existing sources.

The Appendix to the secondary impacts analysis contains the spreadsheets supporting these 

summaries.
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TABLE 4-1. Secondary Emission Impacts for MACT Compliance

Subcategory

Electricity Requirements and 

Emissions (tons/yr)

Supplemental Fuel Requirements and 

Emissions (tons/yr) Total Secondary Emissions (tons/yr)

Mwhr/yrCO2

Emitted

NOx 

Emitted

SO2

Emitted

Million 

ft3

Natural 

Gas/ yr

CO2

Emitted

CO 

Emitted

NOx 

Emitted

CO2

Emitted

CO 

Emitted

NOx 

Emitted

SO2

Emitted

ERU - Liquid/Gas 5,637 3,747 5.46 14.82 - - - - 3,747 - 5.46 14.82

ERU - Solids 146,733 97,530 142.08 385.83 - - - - 97,530 - 142.08 385.83

Incinerators 7,731 5,139 7.49 20.33 - - - - 5,139 - 7.49 20.33

Small, remote 302 201 0.29 0.79 - - - - 201 - 0.29 0.79

Kilns 64,542 42,900 62.50 169.71 1,444 86,612 60.6 72.2 129,512 60.6 134.67 169.71

Totals 224,946 149,516 218 591 1,444 86,612 60.6 72.2 236,128 60.6 290 591

a. National emission factors from Egrid4 for EGUs.

b. Natural gas emission factors from AP-42.5

TABLE 4-2. Secondary Emission Impacts for Lowest Cost Option

Subcategory

Electricity Requirements and 

Emissions (tons/yr)

Supplemental Fuel Requirements and 

Emissions (tons/yr) Total Secondary Emissions (tons/yr)

Mwhr/yrCO2

Emitted

NOx 

Emitted

SO2

Emitted

Million 

ft3

Natural 

Gas/ yr

CO2

Emitted

CO 

Emitted

NOx 

Emitted

CO2

Emitted

CO 

Emitted

NOx 

Emitted

SO2

Emitted

ERU - Liquid/Gas 5,637 3,747 5.46 14.82 - - - - 3,747 - 5.46 14.82

ERU - Solids 146,733 97,530 142.08 385.83 - - - - 97,530 - 142.08 385.83

Incinerators 494 328 0.48 1.30 - - - - 328 - 0.48 1.30

Small, remote 23 15 0.02 0.06 - - - - 15 - 0.02 0.06

Kilns 64,542 42,900 62.50 169.71 1,444 86,612 60.6 72.2 129,512 60.6 134.67 169.71

Totals 217,429 144,519 211 572 1,444 86,612 60.6 72.2 231,132 60.6 283 572

a. National emission factors from Egrid4 for EGUs.

b. Natural gas emission factors from AP-42.5
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5.0 SUMMARY OF SECONDARY IMPACTS FOR NEW SOURCES

While we do not anticipate any new energy recovery units or waste-burning kilns to be 

constructed, it is conceivable that some new units will be installed in the future. It was 

assumed that 1 new incinerator would come into operation over the next five years. We 

anticipate 3 new small, remote units to come online next year and 1 new small, remote 

unit to be constructed each subsequent year. Please see the CISWI compliance cost memo 

for additional details regarding new source assumptions.2

Secondary impacts for new units were determined by applying the methodology 

described above for existing units. Table 5-1 presents the annual impacts anticipated for 

new sources as a result of the CISWI standards. Table 5-2 shows the expected secondary 

emissions from the electricity required for prescribed control devices.

TABLE 5-1. Annual Secondary Impacts for New Sources

Subcategory

Replacement 

Units 

(#/year)1

Electricity 

Required 

(MWh/yr)

Water 

Required 

(gal/yr)

Activated 

Carbon 

Required 

(ton/yr)

Dust 

Produced 

(ton/yr)

Incinerators 0.2 71 979,804 4 5

Small, remote 1.4 23 0 0.75 1.63

Totals - 94 979,804 4.66 6.82

1. It was assumed that 1 new incinerator would come into operation over the next five years, and we anticipate 3 new 

small, remote units to come online next year and 1 new small remote unit to be constructed each subsequent year. 

TABLE 5-2. Secondary Emission Impacts for New Sources

Subcategory

Electricity 

Required 

(MWh/yr)

Emissions from Electricity 

Requirements (tons/year)

CO2

Emitted

NOx 

Emitted SO2 Emitted

Incinerators 71 47 0.07 0.19

Small, remote 23 15 0.02 0.06

Totals 94 62 0.09 0.25

a. National emission factors from Egrid4 for EGUs
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REFERENCES

1. “CISWI Emission Limit Calculations for Existing and New Sources for the 

Reconsideration Final Rule” Memorandum from Eastern Research Group, Inc. to Amy 

Toni Jones, U.S. Environmental Protection Agency. November 16, 2012.

2. “Final Reconsideration Compliance Cost Analyses for CISWI Units” Memorandum 

from Eastern Research Group, Inc. to Toni Jones, U.S. Environmental Protection 

Agency. November 26, 2012.

3. “Final Reconsideration Baseline Emissions and Emissions Reductions Estimates for 

Existing CISWI Units” Memorandum from Eastern Research Group, Inc. to Toni Jones, 

U.S. Environmental Protection Agency. November 26, 2012.

4. EPA eGRID database eGRID2007 Version 1.1. Year 2005 summary tables located at 

www.epa.gov/cleanenergy/documents/egridzips/eGRID2007V1_1_year05_SummaryTab

les.pdf

5. U.S. Environmental Protection Agency, 1995. Compilation of Air Pollutant Emission 

Factors (AP-42), Fifth Edition, Volume 1: Stationary and Point Sources, Chapter 1: 

External Combustion Sources.