1 

MEMORANDUM 

TO: Hillary Ward, U.S. Environmental Protection Agency, OAQPS/Sector Policies and 

Programs Division, Fuel and Incineration Group, Docket 

FROM: Eastern Research Group, Inc. (ERG) 

DATE: July 2015 

SUBJECT: Revised Cost and Emissions Impacts Resulting from the Landfill EG Review 

Introduction 

The purpose of this memorandum is to present the results of the analysis to estimate costs and 

emission reductions for the 2015 supplemental proposed review of the emission guidelines for municipal 

solid waste (MSW) landfills. These impacts were calculated for existing landfills that accepted waste after 

1987 and modified before July 17, 2014. The equations and data inputs used to estimate the impacts are 

discussed in other memoranda in the docket.1, 2,3 

Results are presented in 2012 dollars ($2012) and are based on the annualized costs in 2025 using 

an interest rate of 7 percent. By 2025, the Emission Guidelines are expected to be fully implemented and 

this year is representative of costs and the number of controlling landfills. 

The results of the impacts analysis are presented for the proposed changes to the emission 

guidelines (the proposal) as well as several options. The results are presented as incremental impacts 

relative to impacts associated with the current design capacity and NMOC emission thresholds currently 

in 40 CFR part 60, subpart WWW and the state and federal plans implementing subpart Cf. Landfillspecific details of each option under consideration are documented in the modeling database.4

 This 

memorandum is organized as follows: 

1.0 Overview of Regulatory Options 

2.0 Estimating Cost Impacts 

3.0 Estimating Emission Reductions Impacts 

4.0 Estimating Impacts for Enhanced Surface Emission Monitoring 

Appendix A: Index of Regulatory Options 

Appendix B: Detailed Cost and Emission Reduction Impacts 

 

1

 ERG. 2015. Summary of Updated Landfill Dataset Used in the Cost and Emission Reduction Analysis of 

Landfills Regulations.

2

 ERG. 2015. Updated Methodology for Estimating Cost and Emission Impacts of MSW Landfills 

Regulations.

3

 ERG. 2015. Updated Methodology for Estimating Testing and Monitoring Costs for the MSW Landfill 

Regulations.

4

 ERG. 2015. Summary of Updated Landfill Dataset Used in the Cost and Emission Reduction Analysis of 

Landfills Regulations.
2 

Appendix C: Emissions Profiles 

1. Overview of Regulatory Options 

Descriptions of the current regulatory baseline, the proposed revision, and alternative options are 

included in this section. 

1.1 Baseline 

• Currently, 40 CFR part 60, subpart WWW requires all landfills with a design capacity of 

2.5 million megagrams (Mg) and 2.5 million cubic meters or greater to report their NMOC 

emission rate. When the NMOC emission rate exceeds 50 Mg/yr, a landfill is required to control 

its emissions within 30 months of submitting a report in which the NMOC emissions exceeded 

the threshold. Approximately 989 existing landfills are expected to meet the design capacity 

threshold. Of these 989 landfills, 574 are expected to exceed the NMOC emission threshold and 

install a gas collection and control system (GCCS) by 2025. 

1.2 Proposal 

• The proposal reduces the NMOC emission threshold from 50 Mg/yr to 34 Mg/yr for landfills that 

are open as of the date of this proposal. The number of landfills subject to the rule remains the 

same as the baseline because the design capacity threshold remains the same. However, 106 more 

open landfills are expected to exceed the NMOC emission threshold and install a GCCS by 2025 

when compared to the baseline. 

• Consistent with the current baseline, the proposal employs a modeled initial GCCS installation 

lag time of 3 years after exceeding the NMOC threshold, and an average GCCS expansion lag 

time of 4 years as discussed in another memorandum.5 

1.3 Alternative Regulatory Options 

The impacts of several regulatory options other than proposed option 2.5/34 were also 

considered. The options varied one or more of the size and NMOC control parameters. For each of these 

variations in size and NMOC thresholds, the universe of landfills potentially subject to more stringent 

requirements were analyzed. First, for all landfills (open or closed) meeting the revised criteria and then 

for just landfills that are open as of the date of the proposal and meeting the revised criteria. These options 

are summarized in this memorandum for reference and include the following adjustments to the control 

requirements. A complete index of the characteristics of each option considered is shown in Appendix A. 

• If the proposed threshold of 34 Mg/yr were reduced for all landfills (open and closed), 142 more 

landfills would expect to install a GCCS by 2025 when compared to the baseline. 

• One option incorporated a reduction in the NMOC threshold, to 40 Mg/yr. 62 more open landfills 

are expected to exceed the NMOC emission threshold and install a GCCS by 2025 when 

compared to the baseline. Considering all landfills (open and closed) 84 more landfills would 

install a GCCS in 2025 when compared to the baseline. 

• One option combined a reduced size threshold of 2.0 million Mg design capacity with an NMOC 

emission threshold of 34 Mg/yr. 122 more open landfills are expected to exceed the NMOC 

 

5

 ERG. 2015. Updated Methodology for Estimating Cost and Emission Impacts of MSW Landfills 

Regulations.
3 

emission threshold and install a GCCS by 2025 when compared to the baseline. Considering all 

landfills (open and closed) 162 more landfills would install a GCCS in 2025 when compared to 

the baseline. 

For wet landfills, the EPA also considered options to reduce the lag times to install and expand on the 

GCCS: 

Several options paired the NMOC thresholds of 34 and 40 Mg/yr and size thresholds of 2.0 and 2.5 

million Mg design capacity with shortened the initial lag times for installing the GCCS. For example, 

shortening the initial lag time from 3 years to 2 years would require some landfills to install the controls 

earlier and would also trigger an earlier installation schedule for each subsequent expansion. However, 

because the same subset of landfills would require controls to be installed under the current 3-year lag 

times, the overall additional emission reductions are not as significant over time. Further, when installing 

controls a year earlier as a result of a shortened lag time, the initial system will be designed slightly 

smaller than a system designed to capture gas in a subsequent year. The options that reduced the initial 

lag times also shortened the expansion lag times. Reducing the expansion lag time achieves a larger net 

emission reduction over time because each subsequent expansion is on a shorter 2-year cycle. However, 

the same subset of landfills would still require controls to be installed under either lag time. This 

combination of initial and expansion lag time reductions achieved the largest amount of reductions over 

time because they achieved an earlier installation start date, paired with a tighter frequency of subsequent 

expansions. 

The emission reduction and cost analysis was conducted using a k value of 0.04 for any landfill that is 

located in an area with at least 25 inches of rainfall, consistent with the analysis discussed at 79 FR 

41805. The reductions and cost impacts on wet landfills shown in Appendix B-3a and B-3b were isolated 

for wet landfills, which for the purpose of the preliminary analysis included landfills receiving greater 

than 40 inches of rain fall per year, landfills permitted under the research, development, and 

demonstration (RD&D) rule, or landfills that reported a k value of at least 0.057 to the GHGRP subpart 

HH and indicated they recirculated leachate. Most wet landfills were located in non-arid climate zones, 

but there were nine additional landfills, which are either bioreactor projects permitted under the research, 

development, and demonstration (RD&D) rule or reported significant leachate recirculation to subpart 

HH of the GHGRP were modeled using a k value of 0.02 because they were located in arid areas. The 

results could differ significantly if alternative modeling parameters (k and/or Lo) were used to model 

emissions from this group of wet landfills. 

2. Estimating Cost Impacts 

For each option, the cost impacts analysis compares net annualized costs of the baseline option in 

2025 to the net annualized costs of each regulatory option in 2025. The costs incorporate annualized 

capital costs to install the GCCS, operating and maintenance (O&M) costs for the GCCS, and if relevant, 

any annualized capital and O&M costs for energy recovery equipment. If energy recovery was expected 

to occur at a landfill, the annual revenue from the energy recovery project was subtracted from the total 

annualized costs in order to compute the net annualized cost to each landfill. The detailed control cost 

equations are shown in another memorandum.6 

In addition to the control costs to comply with the regulation, the costs also include testing and 

monitoring costs to demonstrate compliance. The testing and monitoring costs include the labor, 

equipment rental, and any capital expenses involved with preparation of NMOC emission rate reports, 

conducting initial performance tests, monthly wellhead monitoring, continuous combustor monitoring, 

and quarterly surface emission monitoring. The detailed testing and monitoring equations are shown in 

 

6

 ERG. 2015. Updated Methodology for Estimating Cost and Emission Impacts of MSW Landfills 

Regulations.
4 

another memorandum.7 The costs and revenues associated with the baseline and proposal are shown in 

Table 2. 

Table 2. Summary of Cost Impacts for Proposal in 2025 

Option Annualized 

Control 

Cost 

Average 

Annualized 

Revenue 

Average 

Annualized 

Testing and 

Monitoring 

Cost 

Average 

Net Total 

Annualized 

Cost 

Total Costs of Baseline (millions, $2012) 

Baseline 

2.5/50 

1,700 1,408 7.3 299

Incremental Costs above Baseline (millions, $2012) 

Proposal

2.5/34 open 

and 2.5/50 

closed 

102 55.5 0.68 46.8

The incremental costs associated with the other regulatory alternatives as well as a summary of 

each individual cost component are shown in Appendix B. 

3. Estimating Emission Reduction Impacts 

The emission reductions of each regulatory option are presented in terms of NMOC (Mg/yr), 

methane (Mg/yr), and carbon dioxide equivalents (Mg CO2e/yr) based on a global warming potential of 

25 for methane. The detailed emission reductions equations are shown in another memorandum.2 The 

reductions associated with the baseline and the proposal are shown in Table 3. 

Table 3. Summary of Emission Reductions for Proposal in 2025 

Option NMOC 

Reductions 

(Mg/yr) 

Methane 

Reductions 

(million 

Mg/yr) 

Methane 

Reductions 

(million mt 

CO2e/yr)* 

Baseline 57,300 9.0 226

Incremental Reductions above Baseline 

Proposal 

2.5/34 open 

and 2.5/50 

closed 

2,770 0.44 10.9

*A global warming potential of 25 is used to convert methane to CO2-equivalents. Minor secondary air impacts

are not included in this table but are presented in another memorandum.8 

Detailed annual emission reductions for other options for each affected landfill are shown in the 

 

7

 ERG. 2015. Updated Methodology for Estimating Testing and Monitoring Costs for the MSW Landfill 

Regulations.

8

 ERG. 2015. Estimating Secondary Impacts of the Emission Guidelines for MSW Landfills. 
5 

landfill modeling database outputs.9 Table 4 summarizes the overall and incremental cost effectiveness of 

the proposal. The cost effectiveness is presented with and without consideration of project revenue from 

electricity sales. 

Table 4. Summary of Overall Cost-Effectiveness 

Option Net Costa Total 

Cost 

Net Costa Total 

Cost 

Net Costa Total 

Cost 

$/Mg NMOC $/Mg Methane $/CO2e

Baseline 

2.5/50 

5,100 29,800 32.3 189 1.3 7.6 

Proposal

2.5/34 open 

and 2.5/50 

closed 

17,000 37,000 108 235 4.3 9.4 

a Net Cost is the total control and testing and monitoring cost minus any project revenue. The control costs for 

landfills with energy projects includes costs to install and operate a reciprocating engine (and associated electrical 

equipment), which is more expensive than a standard flare. Reciprocating engines are not required by the regulation 

but are expected to be used as control devices when it is cost-effective to recovery the LFG energy. 

The overall cost effectiveness of the baseline is provided for reference and it was calculated by 

dividing the total emission reductions achieved under the baseline by the total costs associated with the 

baseline. The incremental cost effectiveness of the proposal was calculated by dividing the incremental 

costs of the proposal by the incremental reductions of the proposal. 

Additional details about the emission impacts and cost effectiveness of other regulatory 

alternatives can be found in Appendix B. 

4. Impacts Over Time 

While the formal regulatory analysis was based on the costs and benefits in year 2025, the EPA 

recognizes that cost and reduction impacts could vary based on where the landfill is in its lifecycle. This 

variation is not as pronounced when looking at the total impacts of each option in a given snapshot year 

because the landfills controlling in any given year are each at different points of their lifecycle. Appendix 

C presents three different landfills as examples in order to demonstrate how the proposed option affects 

an individual landfill over time. 

 

 

9

 ERG. 2015. Modeling Database Containing Inputs and Results for Review of the MSW Landfill Emission 

Guidelines. 
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Appendix A: Index of Regulatory Options for Landfill Emission Guidelines Review 

Database 

Model 

Option # Option Name Description1 

1, 1a Baseline 

(2.5/50) 

• Design capacity cutoff = 2.5 million Mg 

• NMOC cutoff = 50 Mg/yr 

• Initial lag time = 3 years (30 months in rule, modeled as 3 years to account for 

time between when emission threshold was first exceeded and the time the report 

was submitted) 

• Expansion lag time = 4 years (some will do 2, more will do 5, so use 4 as typical)

3, 3a 2.5/40 Same as current rule, except: • NMOC cutoff = 40 Mg/yr 

4, 4a2 2.5/40, IL, EL Same as current rule, except: • NMOC cutoff = 40 Mg/yr 

• Expansion lag time = 2 years 

• Initial lag time = 2 years 

7, 7a 2.0/34 Same as current rule, except: • Design capacity cutoff = 2.0 million Mg 

• NMOC cutoff = 34 Mg/yr 

13, 13a 2.5/34

PROPOSED 

OPTION 

Same as current rule, except: • NMOC cutoff = 34 Mg/yr 

14, 14a22.5/34, IL, EL Same as current rule, except: • NMOC cutoff = 34 Mg/yr 

• Expansion lag time = 2 years 

• Initial lag time = 2 years 

1 For each option, interest rates of both 3% and 7% were used to annualize the costs. The option number with an “a” 

suffix denotes 3% in the database (i.e. Option 1a) and the option number without this suffix denotes a 7% rate (i.e. 

Option 1) 

2 Options with shorter expansion lag times or initial lag times were evaluated for wet landfills. 

 
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Appendix B: See spreadsheet containing detailed cost and emission reduction impacts. 

 
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Appendix C: Emission Profiles 

• LF ID 1742 would stop controlling in year 2049 under the baseline, but would continue 

on with controls beyond year 2063 with a lower emission threshold. 

• LF ID 52598 would not add controls under the baseline option, but controls would be 

required until 2033 under the lower emission threshold of 34 Mg/yr, according to our 

model. 

• LF 522776 is controlling at the same level throughout the period of 2025-2063, the 

dropoff occurs outside the scope of our modeled emissions.

0

100000

200000

300000

400000

500000

600000

2020202220242026202820302032203420362038204020422044204620482050205220542056205820602062

Mg/yr CO2e Reductions, by landfill

Axis Title

Emissions Profile 2025-2063 for EG (Subpart Cc) Landfills

Baseline - 1742 Proposed Option 2.5/34 - 1742

Baseline - 522776 Proposed Option 2.5/34 - 522776

Baseline - 525598 Proposed Option 2.5/34 - 525598