Methane: An Introduction to
Emission Sources and Reduction Strategies

Richard K. Lattanzio, Coordinator
Analyst in Environmental Policy
Kelsi Bracmort
Specialist in Agricultural Conservation and Natural Resources Policy
James E. McCarthy
Specialist in Environmental Policy
Lynn J. Cunningham
Information Research Specialist
October 1, 2015
Congressional Research Service
7-5700
www.crs.gov
R43860


Methane: An Introduction to Emission Sources and Reduction Strategies

Summary
The Obama Administration’s Strategy to Reduce Methane Emissions

On June 25, 2013, President Obama announced a national “Climate Action Plan” (CAP) to reduce
emissions of carbon dioxide (CO2) and other greenhouse gases (GHGs), as well as to encourage
adaptation to expected climate change. One of the more significant initiatives within the CAP
focused on the control of methane emissions, a potent short-lived climate pollutant. It called for
the U.S. Environmental Protection Agency (EPA) and the Departments of Agriculture, Energy,
Interior, Labor, and Transportation to develop a comprehensive interagency “Strategy to Reduce
Methane Emissions.” The Strategy, released on March 28, 2014, committed to steps to cut
methane emissions by 40%-45% from 2012 levels by 2025 through both voluntary actions and
agency rulemaking. It also outlined the Administration’s efforts to improve the measurement and
assessment of these emissions.
Perspectives on the Strategy
Many of the affected industries (including some in the agriculture, fossil energy, and waste
management sectors) have raised concerns over federal proposals requiring more stringent
controls. They argue that further regulation of emissions would be either insupportable from an
economic standpoint or ineffective at providing significant health and environmental benefits.
Some industry stakeholders contend that they are already doing everything feasible to capture and
reuse methane emissions (for requisite safety and economic reasons) and that state and local
authorities—who share a closer understanding of the industries’ specific circumstances—are best
equipped to oversee and enforce emission reduction efforts within their jurisdictions.
Health and environmental advocates, however, contend that the Strategy and its proposed
rulemakings fall short. They argue that methane emissions can jeopardize worker safety, lead to
ground-level ozone formation (commonly referred to as “smog”), and act as a potent GHG.
Recent events in the United States (e.g., the rise in domestic oil and natural gas production, the
encroachment of domestic oil and natural gas production on new or more populated areas, and the
revitalization of the petrochemical manufacturing sector) have led these stakeholders to suggest
the need for more enforceable standards.
The Role of Methane
Behind it all is methane—the world’s simplest hydrocarbon and the primary component of natural
gas. It is released into the atmosphere by both natural sources (such as wetlands and wildfires)
and human activities (such as oil and natural gas systems, coal mines, landfills, and the raising of
livestock). When captured, methane can be used as either a fuel or a chemical feedstock, with
many advantages over other fossil fuels. (E.g., it is more versatile and less polluting and provides
energy security benefits.) Its dual nature as both a pollutant and a commodity makes efforts to
control emissions potentially beneficial to both the economy and the environment.
For these reasons, as far back as the 1970s, the federal government has sought policies to help
reduce, capture, and reuse methane emissions. Whether strategies to control emissions are
effective and cost-efficient for a given industry may depend upon a number of factors, including
the nature and extent of the emissions, the technology available for capture, and the market price
for the recovered products. In this way, the cost-benefit considerations are similar to those of
energy efficiency efforts, wherein high up-front investments and other market barriers, if
confronted by producers, may be offset over time. Recent federal policies have included a variety
of funding programs for research and technology development as well as voluntary programs and
tax incentives for industry. Currently, methane emissions are addressed directly by two federal
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Methane: An Introduction to Emission Sources and Reduction Strategies

rules: one on new municipal landfills and another on federal oil and gas leases. Since the
Strategy’s release, the Administration has proposed several additional rules—on oil and natural
gas systems, coal mines, and municipal landfills. These proposals—as well as a variety of
legislative efforts in Congress—attest to the continued interest in an appropriate policy response
to the issue of methane emissions.
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Methane: An Introduction to Emission Sources and Reduction Strategies

Contents
Introduction ..................................................................................................................................... 1
Issues for Congress .......................................................................................................................... 3
Legislative Initiatives ................................................................................................................ 5
Administrative Initiatives .......................................................................................................... 6
The Obama Administration’s Strategy to Reduce Methane Emissions .............................. 7
Methane: A Primer ........................................................................................................................... 8
Emissions .................................................................................................................................. 9
Historical Trends ..................................................................................................................... 10
Source Sectors and Mitigation Activities ................................................................................ 13
Agriculture Sector ............................................................................................................. 13
Fossil Energy Sector ......................................................................................................... 15
Waste Management Sector ................................................................................................ 20
Issues in Measurement ............................................................................................................ 22
Conclusion ..................................................................................................................................... 25

Figures
Figure 1. U.S. Methane Emissions: Sources ................................................................................. 10
Figure 2. U.S. Methane Emissions: Historical Trends by Source Sector ....................................... 11
Figure 3. U.S. Methane Emissions: Historical Trends by Source Category .................................. 12
Figure 4. Natural Gas Industry Sectors ......................................................................................... 17

Tables

Table A-1. A Selection of Recent Legislative Proposals with Methane Components ................... 27

Appendixes
Appendix A. Recent Legislative Proposals ................................................................................... 27
Appendix B. Recent Executive Branch Initiatives ........................................................................ 40

Contacts
Author Contact Information .......................................................................................................... 42
Acknowledgments ......................................................................................................................... 42

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Methane: An Introduction to Emission Sources and Reduction Strategies

Introduction
Methane is the world’s simplest hydrocarbon, with a chemical formula CH4 (one atom of carbon
and four atoms of hydrogen). It is gaseous under normal atmospheric conditions and is commonly
produced through the decomposition of organic materials in the absence of oxygen. It is released
into the atmosphere by natural sources such as wetlands, oceans, sediments, termites, volcanoes,
and wildfires,1 as well as human activities such as oil and natural gas systems, coal mines,
landfills, wastewater treatment facilities, and the raising of livestock.
Methane, when captured, can be used as either a fuel or a chemical feedstock. When used as a
fuel—for example, methane is the primary component of natural gas2—it has many advantages
over other hydrocarbons (e.g., coal and oil). Methane is more versatile: It can heat homes, fuel
stoves, run vehicles, fire power plants, and, when liquefied, be exported to support the energy
needs of U.S. allies and trading partners. Methane is cleaner-burning: It emits, on average, about
half as much CO2 as coal and one-quarter less than oil when consumed in a typical electric utility
plant.3 Further, its combustion emits no mercury (a persistent, bioaccumulative neurotoxin),
virtually no particulate matter or sulfur dioxide, and less nitrogen oxides, per unit of combustion,
than either coal or oil. Recent expansion in natural gas production, primarily as a result of
improved technologies (e.g., hydraulic fracturing and directional drilling)4 used on
unconventional resources (e.g., shale, tight sands, and coalbed methane),5 has made methane an
increasingly significant component in the energy supply and security of the United States.
When used as a chemical feedstock, methane is a manufacturing component for a variety of
household and industrial products including plastic, fertilizer, antifreeze, and fabrics. Abundant
and economical supplies of methane may serve arguably to reinvigorate the U.S. petrochemical

1 For a discussion of the sources of naturally occurring methane, see U.S. Environmental Protection Agency (EPA),
Methane and Nitrous Oxide Emissions from Natural Sources, EPA 430-R-10-001, Washington, DC, April 2010.
2 Natural gas extracted through drilling operations by the oil and gas industry is commonly composed of the following:
methane, 70%-90%; ethane, propane, and butane, 0%-20%; carbon dioxide, 0%-8%; oxygen, 0%-0.2%; nitrogen, 0%-
5%; hydrogen sulfide, 0%-5%; and rare gases (e.g., A, He, Ne, Xe) in trace amounts. See the Natural Gas Supply
Association’s educational website, http://naturalgas.org/overview/background/, for further discussion of composition.
3 The stated reduction values are estimates based on carbon dioxide emitted per unit of energy generated. For a more
detailed discussion, see CRS Report R44090, Life-Cycle Greenhouse Gas Assessment of Coal and Natural Gas in the
Power Sector
, by Richard K. Lattanzio.
4 Hydraulic fracturing (hydrofracking, fracking, or fracing) is commonly defined as an oil or gas well completion
process that directs pressurized fluids typically containing any combination of water, proppant, and any added
chemicals to penetrate tight rock formations, such as shale or coal formations, in order to stimulate the oil or gas
residing in the formation and subsequently requires high-rate, extended flowback to expel fracture fluids and solids.
The National Petroleum Council estimates that hydraulic fracturing will account for nearly 70% of natural gas
development within the next decade. See National Petroleum Council, Prudent Development: Realizing the Potential of
North America’s Abundant Natural Gas and Oil Resources
, September 15, 2011. For more discussion on this
technology, see the section on “Hydraulic Fracturing” in CRS Report R42333, Marcellus Shale Gas: Development
Potential and Water Management Issues and Laws
, by Mary Tiemann et al.
5 These unconventional resources are commonly defined as follows: Tight sands gas is natural gas trapped in low-
permeability and nonporous sandstones. Shale gas is natural gas trapped in shale deposits, a very fine-grained
sedimentary rock that is easily breakable into thin, parallel layers. Coalbed methane is natural gas trapped in coal
seams. These resources are referred to as “unconventional” because, in the broadest sense, they are more difficult
and/or less economical to extract than “conventional” natural gas, usually because the technology to reach them had not
until recently been developed fully or had been too expensive. For a more detailed discussion of these definitions, see
the Natural Gas Supply Association’s website, http://naturalgas.org/overview/unconventional-ng-resources/.
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sector, bringing manufacturing industries back on shore and aiding in the creation of domestic
jobs and economic development.6
For these reasons, many in both the public and private sectors have advocated for the increased
production and use of methane (via natural gas extraction or other capture technologies) and have
hailed it as a potential “cost-effective bridge” to a less polluting and lower GHG-intensive
economy.7 This position has been supported by many Members of Congress as well as the Obama
Administration.8
Methane, however, when released or allowed to escape into the atmosphere (commonly referred
to as “vented” and “fugitive” emissions, respectively), has adverse impacts on human health,
safety, and the environment. The U.S. Occupational Safety and Health Administration lists
methane as both an asphyxiant and an explosive, as increased concentrations in local settings can
jeopardize worker safety.9 Further, the U.S. Environmental Protection Agency (EPA) classifies
methane as both a precursor to ground-level ozone formation10 (commonly referred to as “smog”)
and a potent greenhouse gas (GHG), albeit with a shorter atmospheric life than CO2.11 Methane’s
effect on climate change is up to 34 times greater than that of CO2 when averaged over a 100-year
time period and even greater when considered over the first 20 years after it is emitted.12 An
increase in emissions may counteract some of the environmental benefits that the U.S. economy
has to gain by switching from coal or oil to natural gas and other sources of methane. For these
reasons, some stakeholders, including some Members of Congress, have called for increased
controls on methane emissions in several sectors of the economy, including oil and natural gas
production, coal mining, industrial processes, and agriculture.
In many cases, efforts to control air pollution can compete against the economic considerations of
the affected industries. However, in methane’s case, its dual nature as both a commodity and a
pollutant provides a unique set of incentives. Under certain conditions, the value of fugitive
methane and other byproducts that can be recovered and sold at market may be able to offset the

6 “Growth in production of dry natural gas and natural gas plant liquids contributes to the expansion of several
manufacturing industries (such as bulk chemicals and primary metals) and the increased use of [natural gas] feedstocks
in place of petroleum-based naphtha feedstocks.” U.S. Energy Information Administration, Annual Energy Outlook
2015
, April 14, 2015.
7 Ernest J. Moniz et al., The Future of Natural Gas: An Interdisciplinary MIT Study, June 25, 2010.
8 In his 2012 State of the Union speech, President Obama stated, “We have a supply of natural gas that can last
America nearly 100 years, and my administration will take every possible action to safely develop this energy.”
President Barack Obama, “Remarks by the President in State of the Union Address,” Washington, DC, January 24,
2012.
9 U.S. Department of Labor, Occupational Safety and Health Administration, Chemical Sampling Information,
Methane.

10 Health effects associated with exposure to ozone include premature death, heart failure, chronic respiratory damage,
and premature aging of the lungs. Ozone may also exacerbate existing respiratory illnesses such as asthma and
emphysema. See EPA, Regulatory Impact Analysis: Final National Ambient Air Quality Standards for Ozone, July
2011. While methane is a precursor to ground-level ozone formation, it is less reactive than other hydrocarbons. For
further discussion on methane as an ozone precursor, see section “Methane: A Primer.”
11 As a GHG, methane emitted into the atmosphere absorbs terrestrial infrared radiation, which contributes to increased
global warming and continuing climate change. For further discussion on methane as a GHG, see section “Methane: A
Primer.
” For further discussion on climate change and its potential impacts, see CRS Report RL34266, Climate
Change: Science Highlights
, by Jane A. Leggett.
12 Here, as elsewhere in the report, GHGs are quantified using a unit measurement called carbon dioxide equivalent
(CO2e), wherein gases are indexed and aggregated against one unit of CO2. This indexing is referred to as the Global
Warming Potential (GWP) of the gas. For more discussion on GWP, see section “Methane: A Primer.”
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cost of their capture. Further, the value of these recovered products during oil and gas extraction
could contribute to increased royalty payments to state and federal governments.
The difficulty, however, is that methane emissions are not always easy to capture. Methane,
unlike some other pollutants (e.g., sulfur dioxide or CO2), is not commonly emitted in a
concentrated stream from industrial processes. Rather, it is released into the atmosphere through
dispersion, leaks, vents, accidents, and ruptures. In this way, methane emissions are most similar
to those of volatile organic compounds (VOCs), both in manner and control.13 Efforts to capture
or abate these emissions are generally more difficult and costly than for other pollutants. Whether
recovery of methane is profitable for producers may depend upon a number of factors, including
the nature and extent of the release, the technology available for capture, and the market price for
the recovered products. In this way, the cost-benefit consideration of methane capture becomes
very similar to that of energy efficiency efforts, wherein high up-front investments and other
market barriers, if confronted by producers, may have the potential to be offset over time.
This report examines the many facets of methane: from commodity to coproduct to byproduct to
waste. It begins with a survey of past and present attempts by Congress and the executive branch
to address methane emissions for the purposes of energy policy and pollution control. It then
provides a general overview of methane before focusing on specific sectors of the economy in
order to (1) characterize different sources of methane and the data available on their emissions;
(2) discuss current practices, opportunities, and challenges for emission controls; and (3) outline
recent initiatives proposed by Congress and the Administration.
Issues for Congress
Through the years, the federal government has sought policies to control methane emissions for a
variety of economic, environmental, and public health and safety reasons. Some justifications for
federal involvement have included the following:
1. Promoting domestic energy production and energy independence,
2. Protecting the property rights of mineral owners (including federal resources and
associated royalties to the American taxpayer),
3. Assuring the operational safety of employees who work with or near significant
emission sources, and
4. Safeguarding the general population from air pollution that may reasonably be
anticipated to endanger public health or welfare.
Initially, policies to capture methane emissions were motivated in part by the Organization of
Arab Petroleum Exporting Countries oil embargo of 1973 and the subsequent calls for U.S.
energy independence. During this time, the United States saw natural gas and other sources of
methane as a potential alternative to imported crude oil. Efforts to incentivize the capture of
methane and use it as an alternative fuel were proposed by both Congress and the Administration
across the full range of commercial sectors. They included a variety of funding programs for
research and technology development, voluntary guidelines and tax incentives for industry, and/or
rules for mineral rights lessees on federal lands.

13 Like methane, VOCs are difficult to capture because of the diffuse nature of their releases. Also, leak prevention and
recovery of VOCs may pay dividends in reducing product losses. Because the value of VOCs is highly variable, state
and federal regulatory programs have required control of VOC emissions, even when the product value does not result
in a net cost savings to the potential emitter (e.g., National Emission Standards for Hazardous Air Pollutants, vehicle
standards, and State Implementation Plans for ozone precursor controls).
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As an understanding of methane’s role in ozone formation and climate change grew during the
1990s, some state and federal authorities turned their attention to reducing methane emissions as
a form of pollution control. Once again, the key policy tools used for pollution abatement took the
form of voluntary guidelines and tax incentives. However, in a few instances, where reductions in
other pollutants could serve the co-benefit of aiding in the reduction of methane, regulatory
emission standards were proposed and/or promulgated. In the 2000s, as Congress considered
comprehensive market-based strategies to reduce GHG emissions across the entire U.S. economy,
more innovative proposals for methane reduction became prevalent. Methane capture was
commonly suggested as an “offset” credit for higher GHG-emitting industries, as the net costs of
reducing methane emissions, in some instances, could be more favorable than directly controlling
for CO2 emissions.
Recent events in the United States (e.g., the rise in domestic oil and natural gas production, its
encroachment on new or more populated areas, and the revitalization of the petrochemical
manufacturing sector) have led some stakeholders to suggest the need for more enforceable
standards. At the state level, Colorado, Wyoming, Ohio, and California have recently promulgated
or proposed rules to control for methane emissions from their oil and gas sectors.14 At the federal
level, two methane-emitting source categories are addressed directly by regulations. They include
(1) EPA’s 1996 standards on municipal landfills,15 and (2) the Bureau of Land Management’s
(BLM) 1980 notice on venting and flaring for oil and gas leases on federal lands.16
EPA has the authority to regulate methane emissions as both an ozone precursor and a GHG
under the Clean Air Act (CAA).17 Currently, EPA has no standards in place to regulate methane as
an ozone precursor, and it has shown a disinclination for doing so in the past.18 The agency’s
authority to regulate methane as a GHG was upheld by the Supreme Court’s 2007 decision in
Massachusetts v. EPA,19 which determined that GHGs fall under the definition of “air pollutant”
as used in the CAA. Following this decision, EPA determined that six GHGs, including methane,
endangered public health and welfare20 and issued several rules focused primarily on CO2.21
Recently, under the directive of the Obama Administration’s 2014 “Strategy to Reduce Methane

14 See discussion under section “Fossil Energy Sector.”
15 EPA, “Standards of Performance for New Stationary Sources and Guidelines for Control of Existing Sources:
Municipal Solid Waste Landfills,” 61 Federal Register 9905, March 12, 1996. The rule states that “the emissions of
concern are non-methane organic compounds (NMOC) and methane” and that “methane emissions contribute to global
climate change and can result in fires or explosions when they accumulate in structures on or off the landfill site.”
16 U.S. Department of the Interior, “Notice to Lessees and Operators of Onshore Federal and Indian Oil and Gas Leases
(NTL-4A): Royalty or Compensation for Oil and Gas Loss,” January 1, 1980.
17 Clean Air Act, as amended, 42 U.S.C. 7401 et seq. For a summary of the CAA and EPA’s air and radiation activities
and its authorities, see EPA’s website and CRS Report RL30853, Clean Air Act: A Summary of the Act and Its Major
Requirements
, by James E. McCarthy and Claudia Copeland.
18 While methane is a precursor to ground-level ozone formation, it is less reactive than other hydrocarbons. Thus, EPA
has officially excluded it from the definition of regulated hydrocarbons called volatile organic compounds (VOCs). See
EPA, Conversion Factors for Hydrocarbon Emission Components, EPA-420-R-10-015, July 2010.
19 Massachusetts v. EPA, 549 U.S. 497 (2007).
20 EPA, “Endangerment and Cause or Contribute Findings for Greenhouse Gases,” 74 Federal Register 66496,
December 15, 2009. The “endangerment” language in Sections 108, 111, 211, 213, 115, and 231 provides fundamental
authorities. Also, Section 111(d) provides authority to control GHG emissions from existing sources, and Section
111(b) and (e) provide similar authorities for new sources.
21 For example, EPA and National Highway Traffic Safety Administration, “2017 and Later Model Year Light-Duty
Vehicle Greenhouse Gas Emissions and Corporate Average Fuel Economy Standards; Final Rule,” 77 Federal Register
62623, October 15, 2012; and EPA, “Carbon Pollution Emission Guidelines for Existing Stationary Sources: Electric
Utility Generating Units; Proposed Rule,” 79 Federal Register 34829, June 18, 2014.
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Emissions”22 (discussed in further detail in the remainder of this report), EPA proposed a suite of
voluntary and regulatory programs to address methane emissions across a range of industrial
sectors. Additionally, the Departments of Agriculture, Energy, Interior, Labor, and Transportation
have some authorities to monitor, give guidance for, and make rules to control for methane
emissions. As with EPA, some of these agencies have also proposed initiatives under the directive
of the Administration’s Strategy.
Many affected industries—specifically those in the energy and the agricultural sectors—have
raised concerns over increased controls. They argue that further regulation would be either
insupportable from an economic standpoint or ineffective at providing significant health and
environmental benefits. Some industry stakeholders contend that they are already doing
everything feasible to capture and reuse methane emissions (for requisite safety and economic
reasons) and that state and local authorities—who share a closer understanding of an industry’s
specific circumstances—are best equipped to oversee and enforce any emission reduction efforts
within their jurisdictions.
Efforts by the federal government to incentivize the reduction, capture, and reuse of methane—
including the Obama Administration’s Strategy—are summarized in the following two sections:
“Legislative Initiatives” and “Administrative Initiatives.” Further, Table A-1 of Appendix A
provides a detailed list of recent congressional proposals both in support of and in opposition to
increased methane emission controls. Finally, Appendix B provides a selected chronology of
recent executive branch initiatives.
Legislative Initiatives
The U.S. Congress has pursued policies in support of methane reduction since the 1970s.
Legislation aimed at capturing methane emissions from agricultural activities and promoting the
use of the recovered gas dates back, at least, to the 94th Congress.23 Similar bills targeting
emissions from coal mines and municipal landfills were introduced in the 96th and 97th
Congresses, respectively.24 These efforts often promoted methane as an alternative fuel source,
specifically as a replacement for imported crude oil. Legislation addressing methane’s role as an
air pollutant (e.g., as a GHG) reaches back to the 101st Congress, wherein several bills were
introduced with specific methane control provisions. These included one in 1989 by then-Senator
Al Gore to analyze “the contribution of methane to global climate change, the sources and sinks
of methane, and the methods of controlling emissions of methane.”25 A similar set of studies was
codified by the Clean Air Act Amendments of 1990, which required EPA to report on the
“activities, substances, processes, or combinations thereof that could reduce methane emissions
and that are economically and technologically justified.”26 Methane reduction was also included

22 Executive Office of the President (EOP), “Climate Action Plan: Strategy to Reduce Methane Emissions,” March
2014.
23 For example, the Family Farm Energy Conversion Act (S. 3714).
24 For example, the Underground Coal Gasification and Unconventional Gas Research, Development and
Demonstration Act (S. 2774) and the bill “to provide for the development and improvement of the recreation facilities
and programs of Gateway National Recreation Area through the use of funds obtained from the development of
methane gas resources within the Fountain Avenue Landfill site by the City of New York” (S. 2218) ().
25 World Environment Policy Act of 1989 (S. 201).
26 Clean Air Act Amendments of 1990 (S. 1630,). The findings were reported in EPA, Anthropogenic Methane
Emissions in the United States: Estimates for 1990, Report to Congress
, EPA 430-R-93-003, 1993, which was
expanded and replaced by EPA, U.S. Methane Emissions 1990-2020: Inventories, Projections, and Opportunities for
Reductions
, EPA 430-R-99-013, 1999.
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as a qualifying activity in market-based GHG control proposals as far back as the 101st
Congress.27
Recent congressional interest continues to focus on methane’s role as a GHG, with legislative
efforts aimed at both supporting EPA’s authority to regulate methane emissions and revoking it.
Recent bills and amendments in the 114th Congress have proposed several different policy tools as
strategies for reduction. They include (1) providing economic incentives (e.g., tax benefits) for
activities that capture and use fugitive gas (e.g., H.R. 2142, the Capitalizing on American
Methane Act of 2015), (2) authorizing the Administration or a specific agency to investigate or
directly regulate methane emissions (e.g., H.R. 508, the SUPER Act of 2015), and (3) providing a
market-based mechanism (e.g., fee) to incentivize methane reduction (e.g., S. 1548, the American
Opportunity Carbon Fee Act of 2015).
Conversely, many bills in recent Congresses have aimed to remove the executive branch’s
authority to regulate methane emissions based predominantly on arguments for economic growth
and employment. Some examples of these efforts include (1) amending the CAA to remove
“methane” and other GHGs from the definition of “air pollutant” (e.g., H.R. 1806, America
COMPETES Reauthorization Act of 2015) and (2) prohibiting appropriated funds from being
used by agencies to regulate methane (e.g., H.R. 2822, Department of the Interior, Environment,
and Related Agencies Appropriations Act, 2016).
For a selected list of recent bills and amendments that address methane, see Table A-1 of
Appendix A.
Administrative Initiatives
Historically, many of the methane control initiatives administered by the federal government have
taken the form of either research funding or voluntary public-private partnerships with industry.
Federal funding has been provided for the research and development of new technologies aimed
at enabling more cost-effective emission reductions across various sectors of the economy.
Offices that have provided financial and technical assistance in the past include the Department of
Agriculture (USDA) Conservation Innovation Grants, Environmental Quality Incentive Program,
Rural Energy for America Program, Bioenergy Program for Advanced Biofuels, and Biorefinery
Assistance Program; the Department of Energy (DOE) Office of Fossil Fuels, Office of Energy
Policy and Systems Analysis, and Section 1703 Loan Guarantee Program; the Department of
Labor (DOL) Mine Safety and Health Administration; the Department of Transportation (DOT)
Pipeline and Hazardous Materials Safety Administration, the EPA Office of Air and Radiation;
and the Department of the Interior (DOI) BLM.
Similarly, voluntary partnerships managed by federal agencies have aimed to leverage the
resources of the federal government to assist the private sector in overcoming the economic
barriers to methane capture. They include the EPA’s Natural Gas STAR Program and the Coalbed
Methane Outreach Program for the energy sector, EPA/USDA’s AgSTAR Program for the
agricultural sector, EPA’s Landfill Methane Outreach Program for the waste sector, and EPA’s
Global Methane Initiative for international activities.28 The goals of these programs are to (1)
raise awareness of emission levels and the value of lost fuel, (2) provide information and training
on new technologies and practices, and (3) discuss the barriers embedded in traditional

27 CO2 Offsets Policy Enabling Act of 1990 (H.R. 5966).
28 These programs are discussed in more detail in subsequent sections of this report.
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operations, limited infrastructure, and uncertain investment climates. As with many voluntary
initiatives, these programs have returned mixed results.29
The Obama Administration’s Strategy to Reduce Methane Emissions
On June 25, 2013, President Obama refocused his Administration’s efforts to address GHG
emissions with the release of the “Climate Action Plan” (CAP).30 Federal activities in support of
methane emission reductions became one of the cornerstones of the CAP. During its presentation,
the President stated that “curbing emissions of methane is critical to our overall effort to address
global climate change.” Many stakeholders have suggested that the Administration’s recent GHG
reduction targets, offered under the U.S. commitments to the United Nations Framework
Convention on Climate Change,31 would be unattainable without significant methane controls.32
The CAP set guidelines for EPA and the Departments of Agriculture, Energy, Interior, Labor, and
Transportation to develop a comprehensive interagency methane strategy,33 which was released
on March 28, 2014, under the title “Strategy to Reduce Methane Emissions.”
Key initiatives of the Strategy include the following:
1. Agriculture. A joint USDA, EPA, and DOE “Biogas Roadmap” outlining voluntary
strategies to accelerate adoption of methane digesters and other cost-effective
technologies to reduce U.S. dairy sector GHG emissions by 25% by 2020 (released on
August 1, 2014).34
2. Petroleum and Natural Gas.
 An EPA proposal35 to (1) build on the 2012 New Source Performance
Standards (NSPS) for VOC emissions36 to address methane emissions from
new and modified activities and equipment in the sector uncovered by the
previous rule, (2) extend VOC reduction requirements to existing oil and gas
sources in ozone nonattainment areas and states in the Ozone Transport
Region, and (3) expand voluntary efforts under the Natural Gas STAR
program (released August 18, 2015).
 A BLM proposal to update standards to reduce venting and flaring from oil
and gas production on public lands (scheduled for release in October 2015).

29 For a discussion of the performance of these and other voluntary programs, see the subsequent sections of this report
on the respective industry sectors.
30 EOP, The President’s Climate Action Plan, June 2013. For a summary of the CAP, see CRS Report R43120,
President Obama’s Climate Action Plan, coordinated by Jane A. Leggett.
31 For a discussion of the pledged commitments to the UNFCCC, see CRS Report R44092, Greenhouse Gas Pledges by
Parties to the United Nations Framework Convention on Climate Change
, by Jane A. Leggett.
32 See, as one example, projections made by the Climate Action Tracker, an independent scientific analysis produced
by four research organizations, including Climate Analytics, Ecofys, NewClimate Institute, and the Potsdam Institute
for Climate Impact Research, http://climateactiontracker.org/countries/usa.html.
33 CAP, p. 10.
34 U.S. Department of Agriculture, “Fact Sheet: Biogas Opportunities Roadmap: Voluntary Actions to Reduce Methane
Emissions, Increase Energy Independence and Grow the Economy,” August 1, 2014.
35 EPA, “Oil and Natural Gas Sector: Emission Standards for New and Modified Sources, Proposed Rule,” 80 Federal
Register
56593, September 18, 2015.
36 EPA, “Oil and Natural Gas Sector: New Source Performance Standards and National Emission Standards for
Hazardous Air Pollutants Reviews, Final Rule,” 77 Federal Register 49489, August 16, 2012.
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 A Department of Transportation Pipeline and Hazardous Materials Safety
Administration (PHMSA) proposal for natural gas pipeline safety standards
(scheduled for release in 2015).37
 DOE-convened roundtables, as part of the Quadrennial Energy Review, to
identify “downstream” methane reduction opportunities (the summary of
which was released on July 29, 2014).38
3. Coal Mines. A BLM Advance Notice of Proposed Rulemaking (ANPRM) to gather public
input on the development of a program for the capture and sale or disposal of waste mine
methane on lands leased by the federal government (released on April 28, 2014).39
4. Landfills. An EPA proposal to update standards to reduce methane from new and existing
municipal solid waste landfills (released on August 14, 2015).40
5. Improving Methane Measurement. Data quality improvement, including developing new
measurement technologies, addressing areas of higher uncertainty in bottom-up
inventories, and enhancing top-down modeling and monitoring based on direct
measurement of atmospheric concentrations.
These initiatives are summarized in greater detail, by sector, in the remainder of this report. For a
selected chronology of executive branch initiatives related to the White House’s Strategy, see
Appendix B.
Methane: A Primer
Methane is both a precursor to ground-level ozone formation and a potent GHG. As a precursor to
ground-level ozone formation, methane reacts with nitrogen oxides in the presence of sunlight to
form what is commonly referred to as smog. Methane, however, is generally less reactive than
other hydrocarbons. For this reason—and at this time—EPA has excluded it from the definition of
regulated hydrocarbons called volatile organic compounds (VOCs).41
As a GHG, methane emitted into the atmosphere absorbs terrestrial infrared radiation, which
contributes to increased global warming and continuing climate change. According to the
Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report 2013 (AR5), in
2011, methane concentrations in the atmosphere exceeded preindustrial levels by 150%. Further,
they contributed about 16% to global warming due to anthropogenic GHG sources, making
methane the second-leading climate forcer after CO2 globally.42 While the perturbation lifetime
for methane is only 12 years (compared to CO2’s, which is considerably longer and does not
undergo a simple decline over a single predictable timescale), its immediate impacts are
significantly greater (see Text Box). For this reason, methane is commonly characterized as a
“short-lived climate forcer,” along with black carbon and various hydrofluorocarbons (HFCs).


37 For an update on PHMSA pipeline rulemaking, see http://www.phmsa.dot.gov/pipeline/regs.
38 DOE, “Factsheet: An Initiative to Help Modernize Natural Gas Transmission and Distribution Infrastructure,” July
29, 2014.
39 BLM, “Waste Mine Methane Capture, Use, Sale, or Destruction,” 79 Federal Register 23923, April 28, 2014.
40 EPA, “Standards of Performance for Municipal Solid Waste Landfills, Proposed Rule,” August 14, 2015.
41 EPA, Conversion Factors for Hydrocarbon Emission Components, Washington, DC, EPA-420-R-10-015, July 2010.
42 IPCC, Climate Change 2013: The Physical Science Basis, Working Group I Contribution to the Fifth Assessment
Report of the Intergovernmental Panel on Climate Change.
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Global Warming Potential
The climate change impacts of methane are commonly compared to those of CO2 through the use of an index
referred to as “global warming potential” (GWP): a measure of the total energy that a gas absorbs over a particular
period of time compared to CO2. Key factors affecting the GWP of any given gas include its average atmospheric
lifetime and the ability of that molecule to trap heat. While methane is a highly potent GHG for a short period of time
after its initial release, its capacity to trap heat dissipates after approximately 12 years. By comparison, CO2’s
perturbation lifetime is considerably longer and does not undergo a simple decline over a single predictable timescale.
Instead, the excess atmospheric carbon from CO2 emissions mixes into the oceans and biosphere (e.g., plants) over a
period of a few hundred years, and then it is slowly removed over hundreds of thousands of years as it is gradually
incorporated into carbonate rocks.
As recently as November 2013, EPA reported GWP values for methane that were accepted by parties to the United
Nations Framework Convention on Climate Change (UNFCCC) as they were presented in the IPCC Second
Assessment Report 1995
(SAR). The SAR lists methane’s GWP as 21 over a 100-year time horizon. (That is, the same
amount of methane emissions by mass is approximately 21 times more potent than CO2 emissions when averaged
over a 100-year time horizon.) EPA recently adopted GWP values for methane that were accepted by parties to the
UNFCCC as they were presented in the IPCC Fourth Assessment Report 2007 (AR4).43 The AR4 lists methane’s GWP
as 25 and 72 over a 100-year and a 20-year time horizon, respectively. EPA’s most recent Inventory of U.S. Greenhouse
Gas Emissions and Sinks: 1990-2013
, released in April 2015, uses the AR4 values. AR5, released in September 2013,
lists methane’s GWP as 28 and 84 over a 100-year and a 20-year time horizon, respectively, but these values have not
yet been accepted officially by parties to the UNFCCC. Further, the AR5 reports methane’s GWP inclusive of
methane’s indirect effects on aerosols as 34 and 86 over a 100-year and a 20-year time horizon, respectively.
The data in this report are based on EPA’s 2015 Inventory and the IPCC AR4 GWP values for methane.
Emissions
According to EPA, methane is the second-most prevalent GHG emitted by the United States
(behind CO2), and in 2013 it accounted for 636.3 million metric tons of CO2 equivalent, or about
9.5% of all domestically produced emissions from human activities (see Figure 1).44 Some
academic studies have put these emissions higher.45 Of the total, over 40% was emitted from
sources in the energy production sector, over 35% from sources in the agricultural sector, and
over 20% from sources in the waste management sector (see Figure 2).

43 See IPCC, Climate Change 2007: The Physical Science Basis, Working Group I Contribution to the Fourth
Assessment Report of the Intergovernmental Panel on Climate Change, and U.S. Environmental Protection Agency,
“2013 Revisions to the Greenhouse Gas Reporting Rule and Final Confidentiality Determinations for New or
Substantially Revised Data Elements,” 78 Federal Register 71903, November 29, 2013.
44 As calculated over 100 years. EPA, Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990-2013, EPA 430-R-
15-004, April 15, 2015.
45 For further discussion, see section “Issues in Measurement.”
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Figure 1. U.S. Methane Emissions: Sources

Source: CRS, with data from the U.S. Environmental Protection Agency, Inventory of U.S. Greenhouse Gas
Emissions and Sinks: 1990-2013
, EPA 430-R-15-004, April 15, 2015.
Historical Trends
Between 1990 and 2013, methane emissions in the United States decreased by almost 15%.
During this time period, emissions from sources associated with agricultural activities have
increased, while emissions from sources associated with waste management and energy and
industrial processes have decreased (see Figure 2). Comparatively, the source categories for
landfills and coal mining have seen the most notable reductions over the past 20 years (-38% and
-33% respectively) and manure management the most notable increase (+65%), but many other
subcategories have seen little or no change (see Figure 3).
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Figure 2. U.S. Methane Emissions: Historical Trends by Source Sector

Source: CRS, with data from the U.S. Environmental Protection Agency, Inventory of U.S. Greenhouse Gas
Emissions and Sinks: 1990-2013
, EPA 430-R-15-004, April 15, 2015.
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Figure 3. U.S. Methane Emissions: Historical Trends by Source Category

Source: CRS, with data from the U.S. Environmental Protection Agency, Inventory of U.S. Greenhouse Gas
Emissions and Sinks: 1990-2013
, EPA 430-R-15-004, April 15, 2015.
Note: “Other” sources include rice cultivation; stationary and mobile combustion; abandoned coal mines;
petrochemical production; composting; iron, steel, and coke production; and the burning of agricultural residue.
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Source Sectors and Mitigation Activities
Emissions of methane can be categorized into three broad source categories: agriculture, energy
and industrial processes, and waste management. The following section reviews each of these
categories, and
 characterizes the major sources in the sector and the respective data on
emissions,46
 discusses current practices, opportunities, and challenges for emission control,
 summarizes current and applicable government programs and program
performance data, and
 outlines the proposed initiatives in the White House’s recent Strategy.
Agriculture Sector47
Agricultural sources of methane emissions include the following:
Enteric fermentation. Methane is produced as part of normal digestive
processes in animals, which is more so an issue with ruminant livestock (e.g.,
cattle). Microbes that reside in the animal’s digestive system ferment food
consumed by the animal and produce methane as a byproduct, which can be
eructated (i.e., belching or flatulence) by the animal.
Manure management. Methane is produced from manure management systems,
primarily liquid and slurry systems. The treatment and storage of livestock
manure can produce methane through its anaerobic decomposition.
Rice cultivation. Methane is produced from the anaerobic environment resulting
from flooded fields used for rice cultivation. Decomposition of organic material
gradually depletes most of the oxygen present in the soil, causing anaerobic soil
conditions.
Field burning of agricultural residues. Methane is emitted from the field
burning of agricultural residues, which is done usually for disposal purposes.
Field burning of agricultural residues occurs more frequently in some parts of the
United States and is regulated or monitored depending on state and local law.
Internationally, slash-and-burn agriculture is a common form of field burning in
tropical and forested areas.
The agriculture sector constituted approximately 37% of U.S. anthropogenic methane emissions
in 2013.48 From 1990 to 2013, methane emissions from agricultural sources increased by nearly
12% (see Figure 2). Enteric fermentation is the leading source of agricultural methane emissions
and the leading source of methane emissions from all industry sectors. Livestock manure
management is the second-leading agricultural source (see Figure 3).

46 As shown in Figure 3, there are many sources of methane emissions. For editorial reasons, this report focuses only
on the most significant emitters. For greater discussion on smaller sources of emissions (such as forest fires, rice
cultivation, stationary combustion, abandoned coal mines, petrochemical production, mobile combustion, and iron,
steel, and coke production), see EPA, Inventory.
47 This section was authored by Kelsi Bracmort, Specialist in Agricultural Conservation and Natural Resources Policy.
48 EPA, Inventory.
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While best practices exist to reduce methane emitted from enteric fermentation (e.g., diet
modification), it has been economically and technically challenging to systematically capture a
significant portion of the methane emitted at this stage. There are, however, opportunities to
reduce methane emissions from other agricultural sources, and efforts have focused on the
second-largest agricultural source, manure management.
Anaerobic digestion (AD) systems49 employed on stockpiles of manure at animal feeding
operations may offer the most practical and economic method of capture. Operators have
experience with AD systems partly because, for at least the last 20 years, USDA, DOE, and EPA
have supported their use with financial and technical assistance (e.g., EPA/USDA’s AgSTAR
Program, established in 1994).50 There are, however, some economic, operational, and safety
concerns associated with the use of AD systems.51
The Obama Administration’s Strategy takes a two-pronged approach to the reduction of
agricultural methane from manure management. First, the Strategy supports a Biogas Roadmap—
issued by USDA, EPA, and DOE on August 1, 2014—that outlines voluntary strategies to
accelerate the adoption of AD systems and other technologies.52 The Biogas Roadmap is a
deliverable of an April 2013 Memorandum of Understanding between USDA and the Innovation
Center for U.S. Dairy.53 Second, the Strategy supports the continued use of previously established
voluntary efforts (e.g., AD system deployment through assistance from numerous USDA
programs).
If the primary goal of the Administration’s Strategy is methane emission reduction, then the
omission of the sector’s major source of emissions—enteric fermentation—is noteworthy. With
this omission, some may wonder how much impact methane reduction from the agricultural
sector can have. However, if the primary goal is cost-effective methane emission reduction,
addressing manure management may be the most viable option for the agriculture sector at the
moment.
Although federal support for AD systems using voluntary measures is not new, it is difficult to
calculate the full impact of past and continued federal support. It is not clear that an adequate
emissions baseline has been established among the appropriate federal entities for AD systems
that receive federal support. An emissions baseline could allow for long-term analysis, which is
necessary to gauge future impacts (e.g., number of AD systems, number of AD systems that are
fully operational, amount of financial assistance provided, amount of methane captured, amount

49 An AD system feeds manure or other feedstock into a digester that breaks it down in a closed facility in the absence
of oxygen to produce a variety of outputs including methane. The methane can then be captured for use as an energy
source to produce heat or generate electricity. For more information on AD systems, see CRS Report R40667,
Anaerobic Digestion: Greenhouse Gas Emission Reduction and Energy Generation, by Kelsi Bracmort.
50 AgSTAR is a collaborative outreach effort of EPA, USDA, and DOE designed to reduce methane emissions from
livestock waste management operations by promoting the use of biogas recovery systems. For more on the program,
see information at http://www.epa.gov/agstar/. Federal funding opportunities available for AD systems are provided at
http://www.epa.gov/agstar/tools/financing/index.html.
51 AD system concerns include the expense associated with system construction and operation. Additionally, the
technology requires daily operation and maintenance, some of which may exceed the technical capability of the
average agricultural producer. Lastly, if the methane captured from an AD system is generated for electricity and sold
to a utility, there may be utility collaboration concerns, especially regarding whether the utility will accept the
electricity generated and at what price.
52 USDA, “Fact Sheet: Biogas Opportunities Roadmap: Voluntary Actions to Reduce Methane Emissions, Increase
Energy Independence and Grow the Economy,” August 1, 2014.
53 USDA, “USDA and Dairy Producers Renew Agreement to Reduce Greenhouse Gas Emissions and Increase
Sustainability of Dairy Production,” press release, April 24, 2013.
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of methane flared, amount of methane used to generate electricity). Federal program data about
AD systems tend to be disparate. The Strategy may give the federal government an opportunity to
improve methods to document the impact of AD systems.
Beyond the availability and impact of adequate mitigation technologies for the agricultural sector,
economic factors may also dampen the adoption of best practices. For these reasons, it could be
argued that the establishment of a carbon market, the use of direct government payment programs
for mitigating technologies such as anaerobic digestion systems, and the development of
voluntary mitigation-related contracts54 could help alleviate costs and incentivize innovation. On
the other hand, expansion of mitigation technologies such as anaerobic digestion systems may
face challenges larger than economics, such as national infrastructure and cooperation with
utilities or other industries that can use—but do not necessarily agree that they need—the product
being sold.
Fossil Energy Sector55
Fossil energy sources of methane emissions include the following:
Petroleum systems. Methane emissions from petroleum systems are primarily
associated with crude oil production, transportation, and refining operations.
During each of these activities, methane is released to the atmosphere as fugitive
emissions, vented emissions, emissions from operational accidents, and
emissions from incomplete fuel combustion.
Natural gas systems. The U.S. natural gas system encompasses hundreds of
thousands of wells, hundreds of processing and liquefaction facilities, and over 1
million miles of transmission and distribution pipelines. Emissions of methane
(i.e., the principle component of natural gas) arise from vented and fugitive
emissions from system components, natural gas engine and turbine uncombusted
exhaust, bleed and discharge emissions from pneumatic devices, and emissions
from operational accidents.
Coal mining. Three types of coal-mining-related activities release methane to the
atmosphere: underground mining, surface mining, and post-mining (i.e., coal-
handling) activities. While surface mines account for the majority of U.S. coal
production, underground coal mines contribute the largest share of methane
emissions due to the higher methane concentrations in deeper coal seams.
The fossil energy sector constituted nearly 40% of U.S. anthropogenic methane emissions in
2013.56 From 1990 through 2013, methane emissions from fossil energy sources have decreased
by approximately 20% (see Figure 2). Natural gas systems are the leading source of emissions
from the sector, and they have historically vied with enteric fermentation as the leading man-
made source of methane emissions in the United States (see Figure 3). In its 2015 Inventory, EPA
reported that methane emitted by the oil and gas sector had generally declined by 12% since
1990. However, EPA reports that it appears to be on the rise again, corresponding to increases in

54 ICF International, Greenhouse Gas Mitigation Options and Costs for Agricultural Land and Animal Production
within the United States
, February 2013. See chapter 3 of the report for more information on methane emission
reduction potential of selected types of AD systems and break-even costs.
55 This section was authored by Richard Lattanzio, Analyst in Environmental Policy.
56 EPA, Inventory.
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domestic onshore oil and gas production.57 Methane emissions from coal mining have fluctuated
over the past two decades—but for the most part declined—and currently account for
approximately 10% of made-made emissions in the United States.
Taken together, the petroleum and natural gas industry (as shown in Figure 4) is one of the
largest sources of methane emissions in the country, contributing in excess of 28% of U.S.
anthropogenic methane emissions in 2013.58
Sources of emissions in the oil and gas sector include the following:
Upstream production. Methane may be emitted while drilling through gas-
bearing geologic formations, during drilling mud circulation, during well
development (following well stimulation by hydraulic fracturing) when
formation fluids and fracture fluids flow back to the surface, and from field
treatment equipment that separates oil, gas, and water.
Midstream processing and transmission. Gathering lines connecting the
wellhead to oil field treatment equipment that separates gas, oil, and water into
product streams represent another source for fugitive methane and gas
condensate emissions. Leaking valves, transmission lines, and pump stations add
to this sector’s emissions.
Downstream distribution. Emissions from leaking distribution pipelines are
most likely to occur from older pipelines. In 2013, there were more than 1.2
million miles of distribution mains in the United States. Of these, more than
32,000 miles of mains were older cast iron or wrought iron, and more than
61,000 miles were unprotected steel.
Some companies in the oil and gas industries have made significant voluntary reductions in
methane emissions over the past decade. By volume, some of the largest reductions have come
using reduced emissions completions (or “green completions”)59 during hydraulic fracturing
activities, leak detection and repair technologies at processing facilities and compressor stations,
reduced venting of associated gas at oil wells, and the replacement of high‐emitting pneumatic
devices. A number of these technologies and practices have been promoted and supported by
EPA’s public-private partnerships with industry, including the Natural Gas STAR Program60 and
the Coalbed Methane Outreach Program.61 However, voluntary adoption of control techniques
has been uneven across companies and regions. Consequently, in 2012, EPA promulgated
emission standards for conventional pollutants (e.g., volatile organic compounds) for the oil and

57 Ibid.
58 Ibid.
59 A reduced emissions completion is “a well completion following fracturing or refracturing where gas flowback that
is otherwise vented is captured, cleaned, and routed to the flow line or collection system, reinjected into the well or
another well, used as an on-site fuel source, or used for other useful purpose that a purchased fuel or raw material
would serve, with no direct release to the atmosphere.” EPA, “Oil and Natural Gas Sector: New Source Performance
Standards and National Emission Standards for Hazardous Air Pollutants Reviews, Final Rule,” 77 Federal Register
49489, August 16, 2012.
60 EPA’s Natural Gas STAR Program is designed to be a flexible, voluntary partnership that encourages oil and natural
gas companies—both domestically and abroad—to adopt cost-effective technologies and practices that improve
operational efficiency and reduce emissions of methane. For more on the program, including recommended
technologies and practices, see http://www.epa.gov/gasstar/.
61 EPA’s Coalbed Methane Outreach Program is designed to be a voluntary program with a goal of reducing methane
emissions from coal mining activities. For more on the program, including recommended technologies and practices,
see http://www.epa.gov/cmop/.
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gas sector through a series of New Source Performance Standards (NSPS) and National
Emissions Standards for Hazardous Air Pollutants.62 These standards have the co-benefit of
reducing methane emissions from certain new sources in some segments of the gas industry.63
Further, some states have established or proposed regulations that specifically address methane
emissions from the oil and gas industry (e.g., Colorado, California, Ohio, and Wyoming, as well
as a Western Governors’ Association policy resolution).64 Notwithstanding, many sources have
remained uncontrolled by state or federal standards.
Figure 4. Natural Gas Industry Sectors

Source: DTE Energy, Natural Gas Processing, Delivery, and Storage.
Additional to EPA’s standards, BLM has issued rulemakings that indirectly address methane
emissions on federal lands under the Mineral Leasing Act (MLA).65 The MLA authorizes the

62 EPA, Oil and Natural Gas Sector NSPS.
63 For further discussion, see CRS Report R42986, An Overview of Air Quality Issues in Natural Gas Systems, by
Richard K. Lattanzio.
64 See Colorado’s rules at http://www.colorado.gov/cs/Satellite/GovHickenlooper/CBON/1251648046456, California’s
rules at http://leginfo.legislature.ca.gov/faces/billNavClient.xhtml?bill_id=201320140SB1371, Ohio’s proposed rules at
http://www.epa.ohio.gov/dapc/genpermit/genpermits.aspx, Wyoming’s proposed rules at http://deq.state.wy.us/aqd/
proposedrules.asp, and the Western Governors’ Association Policy Resolution 2015-02, Methane Emissions
Regulation, at http://westgov.org/images/stories/policies/RESO_Methane_15-02.pdf.
65 Mineral Leasing Act, as amended and supplemented, 30 U.S.C. 181 et seq. For a summary of the MLA and BLM’s
(continued...)
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Secretary of the Interior to lease onshore lands owned by the United States that contain fossil fuel
deposits, with the federal government retaining title to the lands. The framework of the MLA
provides BLM and the federal government with flexibility to use federal lands to help satisfy the
nation’s energy needs while generating revenue for the federal government and protecting
environmentally sensitive areas. Existing BLM rulemakings affecting methane emissions include
BLM’s 1980 “Notice to Lessees and Operators of Onshore Federal and Indian Oil and Gas Leases
(NTL-4A): Royalty or Compensation for Oil and Gas Loss,”66 which outlines appropriate
payment terms for losses of natural resources under the authority of the MLA. The notice lists
circumstances wherein operators are authorized to vent or flare methane without incurring royalty
obligations.
The Obama Administration’s Strategy targets methane control in the fossil energy sector through
a number of agencies. Since its release, the Administration has proposed a number of
rulemakings,67 including
 An EPA proposal to build on the 2012 NSPS “to set standards for methane and
VOC emissions from new and modified oil and gas production sources, and
natural gas processing and transmission sources”68 (released on August 18,
2015).69 The new standards would extend controls for methane and VOC
emissions beyond the existing requirements to include new or modified
hydraulically fractured oil wells, pneumatic pumps, compressor stations, and leak
detection and repair at well sites, gathering and boosting stations, and processing
plants. EPA estimates that the standards for new and modified sources are
expected to reduce 340,000 to 400,000 short tons of methane in 2025—the
equivalent of reducing 7.7 million to 9 million metric tons of carbon dioxide—
and yield net climate benefits of $120 million to $150 million in 2025.
 An EPA proposal to extend VOC reduction requirements to existing oil and gas
sources in ozone nonattainment areas and states in the Ozone Transport Region
(released on August 18, 2015).70 These requirements would be in the form of
Control Techniques Guidelines and would be similar to the proposed NSPS.
However, Control Techniques Guidelines do not apply any requirements directly
to facilities; rather, they provide recommendations for state and local air agencies
to consider in determining reasonably available control technology for reducing
emissions from covered processes and equipment. States may use different
technology and approaches, subject to EPA approval, provided they achieve the
same level of emissions reductions as would be achieved under the guidelines.

(...continued)
leasing activities, see BLM’s website and CRS Report R40806, Energy Projects on Federal Lands: Leasing and
Authorization
, by Adam Vann.
66 DOI, “Notice to Lessees and Operators of Onshore Federal and Indian Oil and Gas Leases (NTL-4A): Royalty or
Compensation for Oil and Gas Loss,” January 1, 1980.
67 EOP, “Fact Sheet: Administration Takes Steps Forward on Climate Action Plan by Announcing Actions to Cut
Methane Emissions,” January 14, 2015.
68 Ibid. For a discussion of the source categories, see EPA, “White Papers on Methane and VOC Emissions,” April 15,
2014, http://www.epa.gov/airquality/oilandgas/whitepapers.html.
69 EPA, “Oil and Natural Gas Sector: Emission Standards for New and Modified Sources, Proposed Rule,” 80 Federal
Register
56593, September 18, 2015.
70 EPA, “Control Techniques Guidelines for the Oil and Natural Gas Industry (Draft),” EPA-453/P-15-001, August
2015, http://www.epa.gov/airquality/oilandgas/pdfs/og_ctg_draft_081815.pdf.
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 An EPA proposal to clarify the definitions for “major source” categories in the oil
and natural gas sector for the purpose of permitting (released on August 18,
2015).71
 An EPA proposal to expand voluntary efforts under the Natural Gas STAR
program and provide several new mechanisms through which oil and gas
companies could make and track commitments to reduce methane emissions
(released on July 23, 2015).72
 An EPA proposal to strengthen its Greenhouse Gas Reporting Program to require
reporting in all segments of the industry (released on December 9, 2014).73
 A BLM proposal to update standards to reduce venting and flaring from oil and
gas production on federal lands (scheduled for release in October 2015) and an
ANPRM to develop a program for the capture and sale or disposal of waste mine
methane on lands leased by the federal government (released on April 28,
2014).74
 A Department of Transportation PHMSA proposal for natural gas pipeline safety
standards (scheduled for release in 2015).
 The President’s FY2016 budget request for $15 million in funding for DOE to
develop and demonstrate more cost-effective technologies to detect and reduce
losses from natural gas transmission and distribution systems and $10 million in
funding to launch a program to enhance the quantification of emissions from
natural gas infrastructure.
 DOE proposals to issue energy efficiency standards for natural gas and air
compressors, advance research and development to bring down the cost of
detecting leaks, work with Federal Energy Regulatory Commission to modernize
natural gas infrastructure, and partner with local distribution companies to
accelerate pipeline repair and replacement at the local level.
 DOE’s Quadrennial Energy Review, which would include “additional policy
recommendations and analysis on the environmental, safety, and economic
benefits of investments that reduce natural gas system leakage.”75
The Administration states that these proposals are key components under the CAP to put the
United States on track to reduce methane emissions from the oil and gas sector by 40%-45% from
2012 levels by 2025. The oil and natural gas industry has argued against the need for additional
standards, contending that they are unnecessary (due to the historical decline in the sector’s
emissions), duplicative (of many state requirements), and a burden (as many domestic producers
are already doing everything feasible to capture and reuse methane emissions for requisite safety

71 EPA, “Source Determination for Certain Emission Units in the Oil and Natural Gas Sector: Proposed Rule,” 80
Federal Register 56579, September 18, 2015.
72 EPA, Natural Gas STAR Methane Challenge Program Proposal, http://www.epa.gov/gasstar/methanechallenge/
index.html.
73 EPA, “Greenhouse Gas Reporting Rule: 2015 Revisions and Confidentiality Determinations for Petroleum and
Natural Gas Systems; Proposed Rule,” 79 Federal Register 73148, December 9, 2014.
74 BLM, “Waste Mine Methane Capture, Use, Sale, or Destruction,” 79 Federal Register 23923, April 28, 2014.
75 EOP, Fact Sheet. For more discussion, see DOE, “Factsheet: An Initiative to Help Modernize Natural Gas
Transmission and Distribution Infrastructure,” http://energy.gov/articles/factsheet-initiative-help-modernize-natural-
gas-transmission-and-distribution.
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and economic reasons). Health and environmental advocates welcomed the proposed rules but
suggested that the NSPS does not go far enough in addressing existing sources of emissions.
Notwithstanding these criticisms, the possibility remains open for EPA to propose performance
standards on methane emissions for existing sources in the future. That is, for certain pollutants,
promulgation of NSPS under Section 111(b) triggers a mandatory EPA duty under CAA Section
111(d) to address existing sources in the same source category. At present, however, there is a
looming legal question as to precisely what those “certain pollutants” are. This question of which
pollutants trigger the Section 111(d) program for existing sources is likely to be front and center
in the litigation expected soon over EPA’s Clean Power Plan.76 The answer provided by the courts
could affect EPA’s willingness to move forward with regulation of existing sources of methane
from the oil and natural gas sector.
Waste Management Sector77
Waste management sources of methane emissions include the following:
Landfills. Landfill gas—a mixture of roughly 50% methane, 50% CO2, and
small amounts of other gases—is released into the atmosphere if not captured.
The amount of gas produced at any given landfill depends on the amount of
organic material in the waste, the landfill’s design, the climate at the site of the
landfill, and the operating practices used by the site’s operator. In general, large
amounts of organic waste and high levels of moisture in a landfill lead to greater
gas production.
Wastewater treatment. Wastewater from domestic and industrial sources is
commonly treated to remove soluble organic matter and other contaminants.
Soluble organic matter may be removed using biological processes in which
microorganisms consume the organic matter for maintenance and growth. On
occasion, these processes may be accidentally or deliberately managed under
anaerobic conditions, producing methane.
Composting. Composting of organic waste—such as food waste, garden (yard)
and park waste, and sludge—is a common practice in the United States. Methane
is formed in anaerobic sections of the compost, but its impacts are generally
mitigated due to oxygenation in the aerobic sections of the compost.
Waste management and treatment activities constituted approximately 21% of U.S. anthropogenic
methane emissions in 2013. Landfills accounted for approximately 18% of this total, the third-
largest contribution of any methane source in the United States. Landfills emitted 114.6 million
metric tons of CO2 equivalents, or 1.7% of total U.S. GHG emissions (see Figure 1).78 Although
substantial, methane emissions from landfills have declined almost 40% in recent years from a
high of 191.2 million metric tons (MMT) in 1993 (see Figure 3). Additionally, wastewater
treatment and composting of organic waste accounted for 2.4% and less than 1% of U.S. methane
emissions, respectively.
Currently, landfill gas is captured at the nation’s largest landfills. A common landfill gas capture
system consists of an arrangement of vertical wells and horizontal collectors usually installed

76 For further discussion, see CRS Legal Sidebar WSLG781, EPA Regulation of Greenhouse Gases from Existing
Power Plants—Part One: Does the Clean Air Act Allow It?, by Robert Meltz.
77 This section was authored by James E. McCarthy, Specialist in Environmental Policy.
78 EPA, Inventory.
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after a landfill cell has been capped. A 1996 CAA regulation known as the “Landfill Gas Rule”
established NSPS and guidelines that require landfills with a 2.5 MMT design capacity that
accepted waste after November 8, 1987, to capture and burn the gas. The gas can be either flared
or used for energy production—it is often used as fuel for electricity generation. In promulgating
the 1996 rule, EPA said that the 2.5 MMT minimum “corresponds to cities greater than 100,000
people.” The agency also stated that the regulations “will only affect less than 5 percent of all
landfills” but would reduce emissions of methane by 37% at new landfills and by 39% at existing
facilities. Partly as a result of the 1996 regulation, and partly due to tax incentives and voluntary
programs, there are 645 operational methane capture projects at landfills as of March 2015.79 This
represents roughly one-third of the 1,800 to 1,900 operational municipal solid waste landfills
reported in operation by EPA.80
Even under ideal conditions, the capture of landfill gas is a technical challenge in an operationally
dynamic environment. Whatever success existing regulations, tax incentives, and voluntary
programs may be having, a significant amount of methane continues to be emitted even at
landfills subject to the Landfill Gas Rule. In addition, there are few methane capture projects at
smaller landfills and at landfills that ceased operation before November 1987 (those not covered
under the CAA). The latter group, numbering in the tens of thousands of sites, poses a particular
challenge. Often, there is no responsible party who might implement a methane collection system
if the site’s original owner is no longer in business.
Thus, in response to the Administration’s Strategy, EPA is in the process of reviewing the 1996
Landfill Gas Rule and Guideline. On August 14, 2015, the agency released proposed revisions to
the NSPS for new and modified landfills and to the Emission Guidelines for existing landfills.81
The NSPS would make no change in the universe of new or modified landfills subject to its
requirements: The threshold would remain at 2.5 MMTof design capacity (or 2.5 million cubic
meters of waste), but it would change the emission threshold at which landfills would be required
to begin capturing landfill gases. Under the proposed rule, EPA would require that a gas
collection control system be installed and operational within 30 months after landfill gas
emissions reach 34 metric tons of nonmethane organic compounds or more per year. Under the
current NSPS, this threshold is 50 metric tons per year.
EPA expects relatively few landfills to be affected by the proposed NSPS, because few new and
modified landfills will be constructed. According to an agency fact sheet, 127 new, modified, or
reconstructed landfills would be subject to the emission control requirements of the proposed
standards by 2025. The proposal would reduce annual methane emissions by 51,400 metric tons
beginning in 2025, compared to current requirements. This would be the equivalent of reducing
carbon dioxide emissions by 1.3 MMT per year, about 1% of current estimated landfill
emissions.82

79 EPA, Landfill Methane Outreach Program, Energy Projects and Candidate Landfills, http://www.epa.gov/lmop/
projects-candidates/index.html.
80 Slightly different estimates of the number of operational MSW landfills were presented at various points in EPA’s
July 2014 ANPRM for existing MSW landfills. See EPA, “Emission Guidelines and Compliance Times for Municipal
Solid Waste Landfills,” Advance Notice of Proposed Rulemaking, 79 Federal Register 41778, July 17, 2014.
81 The NSPS proposal is actually a supplemental proposal to an earlier version that EPA proposed on July 17, 2014.
The new version lowers the emission threshold at which new, modified, or reconstructed landfills would be required to
begin capturing landfill gas emissions from 40 metric tons per year to 34 metric tons.
82 EPA, “Supplemental Proposal for New Landfills: Fact Sheet,” http://www.epa.gov/ttn/atw/landfill/
20150814nspsfs.pdf.
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The proposed guidelines for existing landfills would require the installation of landfill gas
collection and control systems at active landfills that emit more than 34 metric tons of
nonmethane organic compounds annually, as well. The annual threshold has been 50 metric tons
under the 1996 guidelines. Closed landfills would remain subject to the current threshold of 50
metric tons per year, however.
As a result of the lower threshold for active landfills, EPA estimates that the proposed emission
control requirements would apply at 680 existing open and closed landfills, as compared to 574
facilities currently subject to emission control requirements. Methane emissions are expected to
be reduced by more than 436,000 metric tons annually beginning in 2025 at these existing
facilities, compared to current requirements (the equivalent of reducing 10.9 MMT of CO2). This
would be about a 10% reduction from the current level of landfill methane emissions.83
Issues in Measurement84
Unlike CO2, whose emissions are reported using well-tracked energy statistics,85 methane is
emitted to the atmosphere primarily through fugitive releases of the gas (e.g., leaks in
infrastructure, vapors from landfills, eructation [i.e., belching or flatulence] from livestock). By
definition, fugitive emissions are diffuse, transitory, and elusive. Thus, one of the greater
difficulties in understanding the impacts of methane emissions is acquiring comprehensive and
consistent observational data. Broadly, there are two approaches to measuring fugitive emissions
of methane: “bottom-up” and “top-down.” Each approach has its respective strengths,
weaknesses, and uncertainties. At present, the difference in data acquisition and analysis between
these two approaches has returned competing—and occasionally conflicting—emission estimates.
Bottom-up approaches. Bottom-up methodologies begin by directly measuring
the emissions from a number of randomly selected pieces of equipment or
activities to determine an average “emission factor” (i.e., formula) for each type.
Emissions for the entire industry are then estimated by multiplying these
emission factors by the activity levels for each component (e.g., the total
population of livestock and its diet, the number of oil and gas wellheads and
other components, or the volume of landfill material). Thus, while the inventory
is supported by initial direct measurements, the final results are statistical
averages derived through computation and may not reflect actual emissions in the
field. Because the quality of methane data for some sources can be either absent
or highly variable, bottom-up emission estimates entail considerable uncertainty.
Top-down approaches. Other studies use “top-down” methodologies for the
calculation of leakage (e.g., satellite observations, ambient atmospheric
measurements, and geostatistical inverse modeling). Atmospheric studies use
data sets of ambient concentrations of methane and related hydrocarbons in the
vicinity of the targeted industry, along with the known emission profiles for these
gases from industry operations, to infer the emissions from the sectors. (That is,
these methodologies capture methane emissions from all natural, agricultural,
and industrial activities. Researchers must then parse data estimates for

83 See EPA, “Proposed Emission Guidelines for Existing Landfills: Fact Sheet,” http://www.epa.gov/ttn/atw/landfill/
20150814egfs.pdf.
84 This section was authored by Richard Lattanzio, Analyst in Environmental Policy.
85 According to EPA’s Inventory, over 93% of CO2 emissions in 2013 are attributed to fossil fuel combustion for
energy use. Further, many other CO2 emissions arise from similar combustion processes in various industries.
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attribution to their appropriate sources using such analyses as isotopic ratios or
prevalence signatures from accompanying nonmethane hydrocarbons.) Due to
the technology requirements, these studies are rarer than bottom-up approaches.
As with the bottom-up approaches, different top-down studies have returned
different emission estimates. Further, reported emission rates have varied
considerably across different regions, making source attribution highly uncertain
at the national level.
In general, top-down methodologies have returned higher emission estimates than bottom-up
approaches. Reasons for this discrepancy include (1) researchers may be attributing naturally
occurring methane emissions to man-made sources; (2) researchers may be attributing emissions
inaccurately from one man-made sector to another; (3) atmospheric measurements may capture
emissions that are not accounted for in EPA’s Inventory (e.g., leakage from abandoned gas wells);
(4) atmospheric measurements capture all the gross emitters, accidents, spills, and human errors,
whereas component measurements use emission factors averaged over instances of “normal
operation”; and (5) atmospheric studies may be biased to regions where there is known leakage.
Currently, the primary source of information on methane emissions in the United States is EPA’s
annually published Inventory of U.S. Greenhouse Gas Emissions and Sinks. EPA’s Inventory is a
“bottom-up” approach, employing commonly accepted emission factors and activity levels to
calculate aggregate estimates for all source categories. Methodologies for the Inventory are based
primarily on 2006 guidelines released by the IPCC86 and supplemented with additional domestic
information where available.87 Bottom-up methodologies are used also for EPA’s Greenhouse Gas
Reporting Program,88 as well as the Energy Information Administration’s Natural Gas Annual.
Further, there are many examples of state,89 local, and nongovernmental inventories90
commissioned by a range of stakeholders—from regional and municipal agencies to community
groups and academic institutions.

86 IPCC, 2006 IPCC Guidelines for National Greenhouse Gas Inventories.
87 EPA has undertaken its own emissions studies and modeling practices for the various U.S. sectors, including the
development of the EPA Cattle Enteric Fermentation Model the Gas Research Institute and EPA, Methane Emissions
from the Natural Gas Industry, Volumes 1-15,
GRI-94/0257 and EPA 600/R-96-080, June 1996. EPA also references a
multitude of academic literature for its calculations (see respective references in the Inventory). Further to this, EPA
annually takes comments on its Inventory methodology, and adopts revisions where appropriate.
88 In response to the Consolidated Appropriations Act, 2008 (H.R. 2764; P.L. 110-161), EPA issued the Greenhouse
Gas Reporting Rule (74 Federal Register 56260), which requires reporting of GHG data and other relevant information
from large sources and suppliers in the United States. Sectors include petroleum and natural gas systems, industrial and
municipal landfills, and industrial wastewater treatment facilities but not agriculture or forestry sources. See EPA GHG
Reporting Program website at http://www.epa.gov/ghgreporting/.
89 See, for example, Texas Commission on Environmental Quality, Barnett Shale Phase Two Special Inventory Data,
2011, http://www.tceq.texas.gov/airquality/point-source-ei/psei.html; Colorado Department of Natural Resources
“State to Undertake Major Study on Oil and Gas Emissions,” press release, January 9, 2013, http://dnr.state.co.us/
Media/Pages/PressReleases.aspx; and California Greenhouse Gas Emission Inventory, http://www.arb.ca.gov/cc/
inventory/inventory.htm.
90 See, for example, the Environmental Defense Fund, which, in conjunction with several universities and
environmental engineering firms, announced on October 10, 2012, the launch of a comprehensive study of methane
emissions from natural gas infrastructure in an effort to accumulate new data. These studies replicate the “component
measurement” methodologies of EPA’s Inventory, using current conditions and measurement practices. The first sector
study—production—was published in 2013 (David T. Allen et al., “Measurement of Methane Emissions at Natural Gas
Production Sites in the United States,” Proceedings of the National Academy of Sciences of the United States of
America
, vol. 10, no. 44, pp. 17768-17773, October 29, 2013). For more information, see Environmental Defense
Fund’s Methane Leakage Study at http://www.edf.org/methaneleakage.
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Due to the differences in emission factors, industry reporting, and levels of uncertainty, current
inventories have returned a variety of emission estimates. These differences have also contributed
to periodic revisions to EPA’s Inventory, and these revisions have returned occasionally
significant fluctuations in reporting. (For example, emission estimates in the Inventory for natural
gas systems have fluctuated between 96.4 MMTCO2e and 221.2 MMTCO2e over the past five
years due simply to changes in reporting methodology.) Furthermore, EPA’s Inventory has been
challenged by a number of academic studies as under-reporting methane releases from man-made
sources. (As examples, a 2015 study by Yale researchers concludes that methane emissions from
U.S. landfills may be double EPA’s estimates,91 a 2014 study by federal and academic researchers
suggests that methane emissions from gas-producing areas in Colorado are as much as three times
higher than EPA inventories,92 a 2013 paper published by Harvard University researchers and
federal scientists suggests that EPA’s oil and gas figures may be underestimated in some cases by
as much as 50%,93 and a February 2014 study by Stanford University researchers estimates that
methane leakage from natural gas lines and other sources could be 50% higher than current EPA
estimates.94)
The White House Strategy proposes actions to enhance U.S. methane measurement in support of
two broad goals: (1) improving the bottom-up emission data relevant for mitigation, and (2)
advancing the science and technology for monitoring and validating atmospheric
concentrations.95 Actions in the Strategy include efforts to (1) enhance EPA’s Inventory through
new scientific evidence and data sources, (2) encourage the development of cost-effective
measurement technologies through funding at DOE’s Advanced Research Projects Agency—
Energy, (3) maintain and further develop a nationwide methane monitoring network through
funding at the National Oceanic and Atmospheric Administration,96 and (4) improve local,
regional, and global emission modeling at EPA and DOE. EPA is already in the process of
outlining a comprehensive strategy for significantly improving its methodology for estimating
emissions from the oil and natural gas sector. This effort is in response to recommendations made
by an EPA inspector general report.97 Moving forward, the Strategy will need to find a way to
harmonize the differences in reporting between the bottom-up and top-down studies, dampen the
artificial annual fluctuations in reported estimates, and provide more transparent and unbiased
source data in order to guarantee credibility in EPA’s Inventory for all stakeholders and fairness in
any subsequent rulemaking.

91 Jon T. Powell et al., “Estimates of Solid Waste Disposal Rates and Reduction Targets for Landfill Gas Emissions,”
Nature Climate Change, published online September 21, 2015.
92 Gabrielle Patron et al., “A New Look at Methane and Non-Methane Hydrocarbon Emissions from Oil and Natural
Gas Operations in the Colorado Denver-Julesburg Basin,” Journal of Geophysical Research: Atmospheres, vol. 119,
no. 11 (June 16, 2014), pp. 6836-6852.
93 Scott Miller et al., “Anthropogenic Emissions of Methane in the United States,” Proceedings of the National
Academy of Sciences of the United States of America
, vol. 110, no. 50 (December 10, 2013), pp. 20018–20022.
94 Adam Brandt, et al., “Methane Leaks from North American Natural Gas Systems,” Science, vol. 343, no. 6172
(February 14, 2014), pp. 733-735.
95 EOP, Strategy, pp. 11-14.
96 The President’s FY2015 budget requests $8 million above current funding of $6.5 million for this program.
97 EPA, Office of the Inspector General, “EPA Needs to Improve Air Emissions Data for the Oil and Natural Gas
Production Sector,” Report No. 13-P-0161, February 20, 2013.
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Conclusion
For a variety of economic, environmental, and public health and safety reasons, various
stakeholders have sought policies to reduce, capture, and reuse methane emissions for the past
several decades. But emissions of methane have proven to be difficult to measure and hard to
control. Their naturally occurring presence in the environment, their wide and varied sources of
emissions, and the fugitive nature of their release have contributed to these difficulties.
Nevertheless, methane is a valuable resource. Its dual nature as both pollutant and commodity has
offered a unique opportunity for control, and many strategies have attempted to capitalize on the
economics of recovery. Whether a given control strategy is effective and cost-efficient for a given
industry depends upon a number of factors, including (1) the nature and extent of the emissions,
(2) the technology available for capture, and (3) the market price for the recovered products. (For
example, with declining natural gas prices, the economics of capture technology are less
favorable.) Some significant efforts have been made by industry and some state regulators to
address methane emissions in their particular localities. For its part, the federal government has
contributed funding for research and technology development, voluntary guidelines and tax
incentives for industry, rules for mineral rights lessees on federal lands, and, on occasion, air
pollution standards.
While the most current data on domestic methane emissions show close to a 15% decrease over
the past two decades, the source categories that have contributed to these reductions are few (i.e.,
landfills, coal mines, and natural gas systems). While these industries have made noteworthy
strides in emission reductions through a combination of best management practices and the co-
benefits provided by other air pollution standards, they may represent only the “low-hanging
fruit.” Other sources of methane emissions have confronted greater challenges. They may lack
adequately demonstrated control technologies or cost-effective opportunities. They may not co-
emit methane with other air pollutants and thus may lack the “co-benefits” accrued through other
air quality standards. Some of these sources have seen recent or sustained increases in emissions
(e.g., petroleum systems and manure management, respectively). Other sources (e.g., enteric
fermentation and wastewater treatment) have gone unaddressed for decades, as no economically
viable technology solution has been offered.
The Obama Administration’s recent Strategy—as well as a variety of recent proposals in
Congress—attests to the continued interest in better emission assessments and appropriate policy
responses. In considering strategies moving forward, it may be useful to ask the following
questions:
1. Is the current set of methodologies used for measurement adequate enough to
rationalize and/or prioritize the appropriate controls?
2. Is the projected rise in domestic fossil fuel production and petrochemical
manufacturing significant enough to rationalize and/or prioritize additional
controls?
3. Is the current rate of decline in observed emissions expected to continue, and, if
so, is it sufficient enough to discharge the public health, safety, and
environmental concerns?
4. To what extent might fluctuations in the market price of crude oil and natural gas
affect industry and regulatory efforts in mitigating and/or recovering methane
emissions?
5. To what extent may recently promulgated and proposed rulemaking for air
pollutants commonly co-emitted with methane also serve the co-benefit of
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reducing emissions of methane (e.g., the NSPS for VOCs on the oil and gas
production sector and the petroleum refinery sector, and the revised National
Ambient Air Quality Standard for ozone)?
6. To what extent may the recently proposed rulemakings for methane emissions in
the oil and natural gas sector and the landfill sector serve to (1) curb emissions
from both new and existing sources in each sector and (2) curb the aggregate of
all domestic emissions?
7. If further reductions are under consideration for a given source category, should
the response come from the federal government, state governments, the
industries, or the market?
8. If further reductions are under consideration for a given source category, which
policy tool(s) would be most appropriate: (1) increased funding for technology
research, (2) expanded public-private demonstration projects with industry, (3)
regionally targeted or state-sponsored guidance or rulemaking, (4) methane-
specific state or federal command-and-control air pollution standards, or (5)
economy-wide market-based mechanisms for either ozone or GHG controls?
9. How should the burden of GHG reductions be distributed among the various
GHG emissions sources?
10. How should methane’s other environmental benefits (in comparison to oil and
coal combustion) be weighed in the context of its GHG control?
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Appendix A. Recent Legislative Proposals
Table A-1. A Selection of Recent Legislative Proposals with Methane Components
Cong.
Bill No.
Bill Title
Sponsor
Last Action
Methane Component
114
H.R. 3289
Natural Gas
Rep.
7/29/2015:
The bil would aim to prevent the
Environmental
Lowenthal,
referred to the
waste of gas produced under oil
and Economic
Alan S.
Committee on
and gas leases on federal land and
Security Act
Natural
to col ect royalty on all gas
Resources.
production.
114
H.R. 3140
AMPLE Oil and Rep. Lipinski,
8/4/2015:
The bil would require federal oil
Gas Royalties
Daniel
referred to the
and gas leases to report and pay
Act
Subcommittee
royalties on oil and gas production
on Energy and
based on the actual volume of oil
Mineral
and gas withdrawn under a lease.
Resources.
114
H.R. 2822
Department of
Rep. Calvert,
7/8/2015:
The bil would prohibit any funds
the Interior,
Ken
Committee of
made available in the act to be used
Environment,
the Whole
to promulgate or implement any
and Related
House on the
regulation requiring the issuance of
Agencies
state of the
permits under Title V of the CAA
Appropriations
Union rises
(42 U.S.C. 7661 et seq.) for carbon
Act, 2016
leaving H.R.
dioxide, nitrous oxide, water vapor,
2822 as
or methane emissions resulting
unfinished
from biological processes
business.
associated with livestock
production.
114
H.R. 2202
Tax Pol ution,
Rep.
5/1/2015:
The bil would amend the Internal
Not Profits Act Delaney,
referred to the
Revenue Code to impose an excise
John K.
Committee on
tax on GHG emissions, including
Education and
methane, from fossil fuel products
the Workforce.
and from any facility that is
required to report emissions or to
which emissions are attributed. The
tax is equal to $30 per metric ton
of CO2 or CO2 equivalent in 2016,
increasing each subsequent year at
4% above inflation.
114
H.R. 2142
Capitalizing on
Rep.
4/30/2015:
The bil would amend the Internal
American
Thompson,
referred to the
Revenue Code to include in the tax
Methane Act of Glenn
Committee on
credit for investment in a qualifying
2015
Ways and
gasification project any qualified
Means.
methane conversion technology.
114
H.R. 2111
Wasteful EPA
Rep. Johnson, 5/27/2015:
The bil would prohibit EPA from
Programs
Sam
referred to the
using any funds to implement an
Elimination Act
Subcommittee
ozone standard, including any
of 2015
on
national primary or secondary
Conservation
ambient air quality standard for
and Forestry.
ozone promulgated (or revised)
under Section 109 of the Clean Air
Act, and eliminate funding for the
Global Methane Initiative, among
other EPA GHG programs.
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Cong.
Bill No.
Bill Title
Sponsor
Last Action
Methane Component
114
H.R. 1971
Climate
Rep. Lieu,
4/24/2015:
The bil would require the EPA
Solutions Act
Ted
referred to the
Administrator to promulgate annual
of 2015
Subcommittee
GHG emission reduction targets,
on Energy and
inclusive of methane, for each of
Power.
calendar years 2030 through 2050.
114
H.R. 1926
Robert C. Byrd Rep. Scott,
4/22/2015:
The bil would have required the
Mine Safety
Robert C.
referred to the
Secretary of Health and Human
Protection Act
“Bobby"
Committee on
Services to promulgate regulations
of 2015
Education and
requiring that mining equipment
the Workforce. used in a coal mine incorporate an
atmospheric monitoring and
recording device that samples and
records the methane, oxygen,
carbon monoxide, and coal dust
levels in the mine. The bil was
introduced in the 112th Congress as
S. 3443 and the 113th Congress as
S. 805.
114
H.R. 1806
America
Rep. Smith,
Passed House;
The bil would amend Section
COMPETES
Lamar
5/21/2015:
302(g) of the CAA (42 U.S.C.
Reauthorizatio
received in the
7602(g)) by adding “The term ‘air
n Act of 2015
Senate and read pol utant’ does not include carbon
twice and
dioxide, water vapor, methane,
referred to the
nitrous oxide, hydrofluorocarbons,
Committee on
perfluorocarbons, or sulfur
Commerce,
hexafluoride.”
Science, and
Transportation.
114
H.R. 1487
American
Rep.
4/8/2015:
The bil would amend Section
Energy
Bridenstine,
referred to the
302(g) of the CAA (42 U.S.C.
Renaissance
Jim
Subcommittee
7602(g)) by adding “The term ‘air
Act of 2015
on Indian,
pol utant’ does not include carbon
Insular and
dioxide, water vapor, methane,
Alaska Native
nitrous oxide, hydrofluorocarbons,
Affairs.
perfluorocarbons, or sulfur
hexafluoride.”
114
H.R. 972
Managed
Rep.
2/20/2015:
The bil would amend the Internal
Carbon Price
McDermott,
referred to the
Revenue Code to require U.S. coal
Act of 2015
Jim
Subcommittee
producers, oil refinery operators,
on Energy and
first sellers of natural gas, and
Power.
producers of other GHG emission
substances and importers of any
GHG emission substance to
purchase a federal emission permit
from the Department of the
Treasury for the sale, combustion,
or other use of a GHG emission
substance and would establish
emission reduction targets for 2016
through 2060 decreasing from 90%
to 20% of the CO2 equivalents
emitted in the United States in
2005.
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Cong.
Bill No.
Bill Title
Sponsor
Last Action
Methane Component
114
H.R. 508
SUPER Act of
Rep. Peters,
1/23/2015:
The bil would have required the
2015
Scott H.
referred to the
President to establish a task force
Subcommittee
on short-lived climate pol utants
on Energy and
including methane. The task force
Power.
would review existing and potential
policies that promote emissions
reduction, identify duplications and
gaps in current programs,
recommend efficiencies, and
identify, compile, evaluate, and
develop best practices. The bil was
introduced in the 113th Congress as
H.R. 1943.
114
S. 1645
Department of
Sen.
6/23/2015:
The bil would prohibit any funds
the Interior,
Murkowski,
placed on
made available in the act to be used
Environment,
Lisa
Senate
to promulgate or implement any
and Related
Legislative
regulation requiring the issuance of
Agencies
Calendar under
permits under Title V of the CAA
Appropriations
General
(42 U.S.C. 7661 et seq.) for CO2,
Act, 2016
Orders.
nitrous oxide, water vapor, or
Calendar No.
methane emissions resulting from
126.
biological processes associated with
livestock production.
114
S. 1548
American
Sen.
6/10/2015: read
The bil would amend the Internal
Opportunity
Whitehouse,
twice and
Revenue Code of 1986 to provide
Carbon Fee
Sheldon
referred to the
for CO2 and other GHG emission
Act of 2015
Committee on
fees, including supplemental fees for
Finance.
escaped methane from coal,
petroleum, and natural gas
production activities. Further, the
bil would establish and implement
a program to provide for the
col ection of data on methane
emissions by major non-natural
sources, including methane
emissions attributable to the
extraction and distribution of coal,
petroleum products, and natural
gas.
114
S. 1264
Renewable
Sen. Udal ,
5/19/2015:
The bil would amend the Public
Electricity
Tom
Committee on
Utility Regulatory Policies Act of
Standard Act
Energy and
1978 to establish a renewable
Natural
electricity standard, including
Resources.
landfil methane as a category of
Hearings held.
biogas.
114
S. 1215
Methane
Sen.
5/19/2015:
The bil would amend the Methane
Hydrate
Murkowski,
Committee on
Hydrate Research and
Research and
Lisa
Energy and
Development Act of 2000 to
Development
Natural
provide for the development of
Amendments
Resources.
methane hydrate as a commercially
Act of 2015
Hearings held.
viable source of energy.
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Methane: An Introduction to Emission Sources and Reduction Strategies

Cong.
Bill No.
Bill Title
Sponsor
Last Action
Methane Component
114
S. 1208
Pipeline
Sen. Markey,
5/6/2015: read
The bil would require operators of
Modernization
Edward J.
twice and
a gas pipeline facility, in accordance
and Consumer
referred to the
with an integrity management
Protection Act
Committee on
program, to accelerate the repair,
Commerce,
rehabilitation, and replacement of
Science, and
gas piping or equipment that is
Transportation.
leaking or may pose high risk of
leaking. Further, the bil would
direct the administrator of the
Pipeline and Hazardous Materials
Safety Administration to issue
nonbinding best practices guidelines
for identifying and classifying high-
risk pipeline infrastructure and
leaks for repair or replacement.
114
S. 1145
Robert C. Byrd Sen. Casey,
4/30/2015: read
The bil would have required the
Mine Safety
Robert P., Jr.
twice and
Secretary of Health and Human
Protection Act
referred to the
Services to promulgate regulations
of 2015
Committee on
requiring that mining equipment
Health,
used in a coal mine incorporate an
Education,
atmospheric monitoring and
Labor, and
recording device that samples and
Pensions.
records the methane, oxygen,
carbon monoxide, and coal dust
levels in the mine. The bil was
introduced in the 112th Congress as
S. 3443 and the 113th Congress as
S. 805.
114
S. 828
Fracturing
Sen. Inhofe,
3/19/2015: read
The bil would give states the sole
Regulations are James M.
twice and
authority to promulgate or enforce
Effective in
referred to the
any regulation, guidance, or permit
State Hands
Committee on
requirement regarding hydraulic
Act
Energy and
fracturing on or under any land
Natural
within their boundaries.
Resources.
114
S. 791
American
Sen. Cruz,
3/18/2015: read
The bil would amend Section
Energy
Ted
twice and
302(g) of the CAA (42 U.S.C.
Renaissance
referred to the
7602(g)) by adding “The term ‘air
Act of 2015
Committee on
pol utant’ does not include carbon
Energy and
dioxide, water vapor, methane,
Natural
nitrous oxide, hydrofluorocarbons,
Resources.
perfluorocarbons, or sulfur
hexafluoride.”
113
H.R. 3895
Energy
Rep. Duncan, 6/20/2014:
The bil would have aimed to
(H.R. 4286,
Exploration
Jeff
referred to
reduce or eliminate financial,
H.R. 4304,
and Production
House
regulatory, and technical barriers to
and S. 2170
to Achieve
subcommittee.
energy exploration and production.
include
National
It would have amended Section
similar
Demand Act
302(g) of the CAA (42 U.S.C.
provisions.)
7602(g)) by adding “The term ‘air
pol utant' does not include carbon
dioxide, water vapor, methane,
nitrous oxide, hydrofluorocarbons,
perfluorocarbons, or sulfur
hexafluoride."
Congressional Research Service
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Methane: An Introduction to Emission Sources and Reduction Strategies

Cong.
Bill No.
Bill Title
Sponsor
Last Action
Methane Component
113
H.R. 3547
Consolidated
Rep. Smith,
1/17/2014:
The bil prohibited any funds made
Appropriations
Lamar
became P.L.
available in the act to be used to
Act, 2014
113-76.
promulgate or implement any
regulation requiring the issuance of
permits under Title V of the CAA
(42 U.S.C. 7661 et seq.) for CO2,
nitrous oxide, water vapor, or
methane emissions resulting from
biological processes associated with
livestock production.
113
H.R. 3424
Converting
Rep. Larson,
10/30/2013:
The bil would have amended the
Methane Into
John B.
referred to
Internal Revenue Code to (1)
Petroleum Act
House
include in the tax credit for
of 2013
committee.
investment in a qualifying
gasification project any qualified
methane conversion technology,
and (2) allow an alternative fuel
excise tax credit for liquid fuel
produced through qualified
methane conversion technology at
a facility. It defined “qualified
methane conversion technology" as
a process for the molecular
conversion of methane into other
hydrocarbons and the use of such
hydrocarbons to replace or reduce
the quantity of petroleum present
in motor vehicle fuel and for the
production of chemicals.
113
H.Amdt. 507
Amendment to
Rep. Holt,
11/20/2013:
Amendment would have allowed
H.R. 2728
Rush
House
the Secretary of the Interior to
amendment not
issue regulations to reduce
agreed to; failed methane emissions from oil and gas
by recorded
dril ing operations on public lands.
vote: 190-230
(Rol no. 601).
113
H.R. 1943
SUPER Act of
Rep. Peters,
5/10/2013:
The bil would have required the
2013
Scott H.
referred to
President to establish a task force
House
on short-lived climate pol utants
subcommittee.
including methane. The task force
would review existing and potential
policies that promote emissions
reduction, identify duplications and
gaps in current programs,
recommend efficiencies, and
identify, compile, evaluate, and
develop best practices.
113
H.Amdt. 512
Amendment to
Rep. Tonko,
11/21/2013:
The amendment would have
H.R. 1900
Paul
House
required an application for a natural
amendment not
gas pipeline to include information
agreed to; failed ensuring that methane emissions
by recorded
would be minimized before such
vote: 183-233
application can be considered for
(Rol no. 605).
approval.
Congressional Research Service
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Methane: An Introduction to Emission Sources and Reduction Strategies

Cong.
Bill No.
Bill Title
Sponsor
Last Action
Methane Component
113
H.R. 621
Ensuring
Rep. Poe,
2/15/2013:
The bil would have prohibited any
Affordable
Ted
referred to
funds appropriated or otherwise
Energy Act
House
available for the EPA Administrator
subcommittee.
from being used to implement or
enforce (1) a cap-and-trade
program, or (2) any statutory or
regulatory requirement pertaining
to emissions of one or more
GHGs, including methane, from
stationary sources.
113
H.R. 83
Consolidated
Rep.
12/16/2014:
The bil prohibited any funds made
and Further
Christensen,
became P.L.
available in the act to be used to
Continuing
Donna M.
113-235.
promulgate or implement any
Appropriations
regulation requiring the issuance of
Act, 2015
permits under Title V of the CAA
Act (42 U.S.C. 7661 et seq.) for
CO2, nitrous oxide, water vapor,
or methane emissions resulting
from biological processes
associated with livestock
production and any provision in a
rule requiring mandatory reporting
of GHG emissions from manure
management systems.
113
S. 2940
American
Sen.
11/19/2014:
The bil would have amended the
Opportunity
Whitehouse,
referred to
Internal Revenue Code to impose a
Carbon Fee
Sheldon
Senate
fee on (1) fossil fuel products
Act
committee.
including coal, petroleum products,
and natural gas, for CO2 emissions;
and (2) emissions of any GHG,
including methane, from any GHG
emission source. The bil would
have established, implemented, and
reported on a program to col ect
data on methane emissions by
major non-natural sources,
including emissions attributable to
the extraction and distribution of
coal, petroleum products, and
natural gas.
113
S. 2911
Super
Sen. Murphy,
12/2/2014:
The bil would have established a
Pol utants Act
Chris, and
Committee on
task force to review policies and
of 2014
Sen. Col ins,
Environment
measures to promote, and develop
Susan
and Public
best practices for, reduction of
Works.
short-lived climate pol utants
Hearings held.
including methane.
Congressional Research Service
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Methane: An Introduction to Emission Sources and Reduction Strategies

Cong.
Bill No.
Bill Title
Sponsor
Last Action
Methane Component
113
S. 2739
Biogas
Sen.
7/31/2014:
The bil would have amended the
(H.R. 860
Investment Tax Schumer,
referred to
Internal Revenue Code to allow for
includes
Credit Act of
Charles
Senate
an energy tax credit through 2018
similar
2014
committee.
for investment in qualified biogas
provisions.)
property, among other things.
Eligible qualified biogas property
was defined as including systems
that use anaerobic digesters or
other biological, chemical, thermal,
or mechanical processes (alone or
in combination) to convert biomass
into methane for use as a fuel.
113
S. 805
Robert C. Byrd Sen.
4/24/2013:
The bil would have required the
Mine and
Rockefeller,
referred to
Secretary of Health and Human
Workplace
John D., IV
Senate
Services to promulgate regulations
Safety and
committee.
requiring that mining equipment
Health Act of
used in a coal mine incorporate an
2013
atmospheric monitoring and
recording device that samples and
records the methane, oxygen,
carbon monoxide, and coal dust
levels in the mine. The bil was
introduced in the 112th Congress
as S. 3443.
113
S. 332
Climate
Sen. Sanders,
2/14/2013:
The bil would have required the
Protection Act
Bernard
referred to
EPA Administrator to impose a fee
of 2013
Senate
on any manufacturer, producer, or
committee.
importer of a GHG pol uting
substance and submit to Congress
a report describing the quantity of
fugitive methane emissions emitted
as a result of any leak in natural gas
infrastructure, including
recommendations for eliminating
each such leak.
112
H.R. 6212
Biogas
Rep. Kind,
7/26/2012:
The bil would have amended the
Investment Tax Ron
referred to
Internal Revenue Code to allow for
Credit Act of
House
an energy tax credit through 2018
2012
committee.
for investment in qualified biogas
property. Eligible qualified biogas
property was defined as including
systems that use anaerobic
digesters or other biological,
chemical, thermal, or mechanical
processes (alone or in combination)
to convert biomass into methane
for use as a fuel.
Congressional Research Service
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Methane: An Introduction to Emission Sources and Reduction Strategies

Cong.
Bill No.
Bill Title
Sponsor
Last Action
Methane Component
112
H.R. 2055
Consolidated
Rep.
12/23/2011:
The bil prohibited any funds made
Appropriations
Culberson,
became P.L.
available in the act or any other act
Act, 2012
John Abney
112-74.
to be used to promulgate or
implement any regulation requiring
the issuance of permits under Title
V of the CAA (42 U.S.C. 7661 et
seq.) for CO2, nitrous oxide, water
vapor, or methane emissions
resulting from biological processes
associated with livestock
production.
112
H.R. 199
Protect
Rep. Capito,
2/1/2011:
The bil would have suspended,
(S. 231 and
America’s
Shelley
referred to
during the two-year period
S.Amdt. 215
Energy and
Moore
House
beginning on the date of enactment
to S. 493
Manufacturing
subcommittee.
of the act, any EPA action under
include
Jobs Act of
the CAA with respect to CO2 or
similar
2011
methane pursuant to certain
provisions.)
proceedings, other than with
respect to motor vehicle emissions.
112
H.R. 153
Ensuring
Rep. Poe,
2/1/2011:
The bil would have prohibited any
Affordable
Ted
referred to
funds appropriated or otherwise
Energy Act
House
available for the EPA Administrator
subcommittee.
from being used to implement or
enforce (1) a cap-and-trade
program, or (2) any statutory or
regulatory requirement pertaining
to emissions of one or more
GHGs, including methane, from
stationary sources.
112
H.R. 97
Free Industry
Rep.
2/1/2011:
The bil would have amended
(H.R. 1023,
Act
Blackburn,
referred to
Section 302(g) of the CAA (42
H.R. 1287,
Marsha
House
U.S.C. 7602(g)) by adding “The
H.R. 1292,
subcommittee.
term ‘air pol utant' does not include
H.R. 1777,
carbon dioxide, water vapor,
H.R. 3400,
methane, nitrous oxide,
H.R. 4301, S.
hydrofluorocarbons,
706, S. 1720,
perfluorocarbons, or sulfur
S. 2199, and
hexafluoride." Some similar bil s
S. 2365
focused solely on the exclusion of
include
agricultural emissions.
similar
provisions.)
112
S. 3443
Robert C. Byrd Sen.
7/25/2012:
The bil would have required the
Mine and
Rockefeller,
referred to
Secretary of Health and Human
Workplace
John D., IV
Senate
Services to promulgate regulations
Safety and
committee.
requiring that mining equipment
Health Act of
used in a coal mine incorporate an
2012
atmospheric monitoring and
recording device that samples and
records the methane, oxygen,
carbon monoxide, and coal dust
levels in the mine.
Congressional Research Service
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Methane: An Introduction to Emission Sources and Reduction Strategies

Cong.
Bill No.
Bill Title
Sponsor
Last Action
Methane Component
111
H.R. 6511
Ensuring
Rep. Poe,
12/9/2010:
The bil would have prohibited any
Affordable
Ted
referred to
funds appropriated or otherwise
Energy Act
House
available for the EPA Administrator
committee.
from being used to implement or
enforce (1) a cap-and-trade
program, or (2) any statutory or
regulatory requirement pertaining
to emissions of one or more
GHGs, including methane, from
stationary sources.
111
H.R. 4753
Stationary
Rep. Rahall,
3/4/2010:
The bil would have suspended,
(S. 3072
Source
Nick J., II
referred to
during the two-year period
includes
Regulations
House
beginning on the date of enactment
similar
Delay Act
committee.
of the act, any EPA action under
provisions.)
the CAA with respect to CO2 or
methane pursuant to certain
proceedings, other than with
respect to motor vehicle emissions.
111
H.R. 3598
Energy and
Rep. Gordon, 12/1/2009:
The bil would have directed the
Water
Bart
passed/agreed
Secretary of Energy to identify each
Research
to in House by
of DOE’s energy research,
Integration Act
voice vote.
development, and demonstration
12/2/2009:
programs and projects into which it
referred to
would be appropriate to integrate
Senate
water considerations. This included
committee.
developing a strategic plan to
evaluate and establish technical
milestones for technologies to treat
and utilize produced waters
discharged from oil, natural gas,
coalbed methane, and mining
activities, among others.
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Methane: An Introduction to Emission Sources and Reduction Strategies

Cong.
Bill No.
Bill Title
Sponsor
Last Action
Methane Component
111
H.R. 3534
Consolidated
Rep. Rahall,
7/30/2010:
The bil , as introduced in the
Land, Energy,
Nick J., II
passed/agreed
House, would have amended the
and Aquatic
to in House by
Mineral Leasing Act (30 U.S.C. 201
Resources Act
the Yeas and
et seq.) to require any federal coal
of 2010
Nays: 209-193,
lease and any modification of an
1 Present (Rol
existing coal lease to include terms
no. 513).
that establish (1) the inclusion of
8/4/2010:
methane released in conjunction
placed on
with mining activities within the
Senate
scope of the lease if the United
Legislative
States owns both the coal and gas
Calendar under
resources, (2) a requirement that
General
the lessee recover the associated
Orders.
methane to the maximum feasible
extent, (3) a requirement to
analyze the extent to which
associated methane can be
economically captured, and (4) a
requirement that any federal coal
mine methane resources that are
captured and used or sold pursuant
to a federal coal lease be subject to
a royalty of not less than 12.5%.
(These provisions were not
included in the bil as reported or
engrossed in the House or placed
on the Senate calendar.)
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Methane: An Introduction to Emission Sources and Reduction Strategies

Cong.
Bill No.
Bill Title
Sponsor
Last Action
Methane Component
111
H.R. 2454
American
Rep.
6/26/2009:
The bil would have set forth
Clean Energy
Waxman,
passed/agreed
provisions concerning clean energy,
and Security
Henry A.
to in House;
energy efficiency, reducing global
Act of 2009
passed by
warming pol ution, transitioning to
recorded vote:
a clean energy economy, and
219-212 (Rol
providing for agriculture and
no. 477).
forestry related offsets. The bil
7/7/2009:
would have required the EPA
placed on
Administrator to establish a cap-
Senate
and-trade system for GHG
Legislative
emissions and set goals for reducing
Calendar under
such emissions from covered
General
sources by 83% of 2005 levels by
Orders.
2050. Methane was defined as a
GHG, given a GWP of 25, and
included in the offset program. Any
source category that was
responsible for at least 10% of the
uncapped methane emissions in
2005 was covered under the
program. Methane recovered from
landfil gas, wastewater treatment
gas, coal mine methane used to
generate electricity at or near the
mine mouth, and qualified waste-to-
energy projects were covered
under the program’s renewable
electricity standard. The bil would
have explicitly exempted
agriculture from the cap-and-trade
program.
111
H.R. 1426
To amend the
Rep. Lucas,
3/12/2009:
The bil would have amended the
(S. 527
Clean Air Act
Frank D.
referred to
CAA to prohibit the issuance of
includes
to prohibit the
House
permits under Title V of that act
similar
issuance of
subcommittee.
for any CO2, nitrogen oxide, water
provisions.)
permits under
vapor, or methane emissions
title V of that
resulting from biological processes
Act for certain
associated with livestock
emissions from
production.
agricultural
production
111
H.R. 1158
Biogas
Rep. Higgins,
2/24/2009:
The bil would have amended the
Production
Brian
referred to
Internal Revenue Code to allow for
Incentive Act
House
an energy tax credit for investment
of 2009
committee.
in qualified biogas property. Eligible
qualified biogas property was
defined as including systems that
use anaerobic digesters or other
biological, chemical, thermal, or
mechanical processes (alone or in
combination) to convert biomass
into methane for use as a fuel.
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Methane: An Introduction to Emission Sources and Reduction Strategies

Cong.
Bill No.
Bill Title
Sponsor
Last Action
Methane Component
111
H.R. 469
Produced
Rep. Hall,
2/11/2009:
The bil would have set forth
Water
Ralph M.
passed House
provisions for the Secretary of
Utilization Act
on voice vote.
Energy to encourage research,
of 2009
2/12/2009:
development, and demonstration of
received in
technologies to facilitate the
Senate and
utilization of water produced in
referred to
connection with the development
committee.
of domestic energy resources
including coalbed methane, oil,
natural gas, or any other substance
to be used as an energy source.
111
H.R. 391
To amend the
Rep.
1/14/2009:
The bil would have amended
Clean Air Act
Blackburn,
referred to
Section 302(g) of the CAA (42
to provide that
Marsha
House
U.S.C. 7602(g)) by adding “The
greenhouse
subcommittee.
term ‘air pol utant' does not include
gases are not
carbon dioxide, water vapor,
subject to the
methane, nitrous oxide,
Act, and for
hydrofluorocarbons,
other purposes
perfluorocarbons, or sulfur
hexafluoride." Some similar bil s
focused on this definition solely
with respect to agricultural
emissions.
111
S. 2729
Clean Energy
Sen.
11/4/2009:
The bil would have set forth
Partnerships
Stabenow,
referred to
provisions to establish a program
Act of 2009
Debbie
Senate
to govern the creation of credits
committee.
from emission reductions from
uncapped domestic sources and
sinks. The bil would have required
the Secretary of Agriculture and
the EPA Administrator to establish
a cap-and-trade system for GHG
emissions. Methane controls were
an eligible offset activity and
included col ection and combustion
projects at mines, landfil s, natural
gas systems; manure management,
composting, or anaerobic digestion;
recycling and waste minimization;
rice cultivation; and animal
management practices including
dietary modifications and pasture-
based livestock systems. Further,
the bil would have exempted the
requirement to hold allowances for
emissions resulting from the use of
gas as an energy source if the gas
was derived from a domestic
methane offset project. The bil
included research and
demonstration assistance for
approaches to reducing methane
emissions associated with
agricultural production (including
livestock and crop production),
including quantification of those
reductions.
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Methane: An Introduction to Emission Sources and Reduction Strategies

Cong.
Bill No.
Bill Title
Sponsor
Last Action
Methane Component
111
S. 1733
Clean Energy
Sen. Kerry,
2/2/2010:
The bil would have set forth
Jobs and
John F.
reported out of
provisions concerning the
American
the Committee
reduction of global warming
Power Act
on Environment pol ution, energy efficiency,
and Public
renewable energy, water efficiency,
Works; placed
green jobs and worker transition,
on Senate
and adaptation to the impacts of
Legislative
climate change. The bil would have
Calendar under
required the EPA Administrator to
General
establish a cap-and-trade system for
Orders.
GHG emissions. Methane was
defined as a GHG, given a GWP of
25, and included in the offset
program. Eligible offset activity
included methane col ection and
combustion projects at active
underground coal mines, landfil s,
oil and natural gas systems, and
manure management and biogas
facilities.
111
S. 1462
American
Sen.
7/16/2009:
The bil would have required the
Clean Energy
Bingaman, Jeff placed on
Secretary of Energy, in consultation
Leadership Act
Senate
with other appropriate agencies, to
of 2009
Legislative
support a civilian research program
Calendar under
to develop advanced membrane
General
technology that would be used in
Orders.
the separation of gases from
applications, including those that
pul gases from landfil s and
separate out methane.
Source: CRS.
Notes: This section was prepared with the assistance of Lynn J. Cunningham, Information Research Specialist.
The table lists only those bil s that specifically mention “methane.” Bil s are ordered by Congress, split between
the House and the Senate, and arranged by bil number starting with the most recent. If similar language is
contained in different bil s from the same Congress, the first bil introduced is presented in the table (with the
subsequent bil numbers given in parentheses).
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Methane: An Introduction to Emission Sources and Reduction Strategies

Appendix B. Recent Executive Branch Initiatives
A Selected Chronology of Recent Executive Branch Initiatives
June 25, 2013
White House released “The President's Climate Action Plan" (CAP) with a stated
goal of "reducing methane emissions" through the development of an interagency
strategy and the pursuit of col aborative approaches across the economy.
November 29, 2013
EPA released a Final Rule (FR) to amend the GHG reporting rule to raise the 100-
year GWP of methane from 21 to 25, in line with the 2007 IPCC AR4 findings
agreed to by parties to the UNFCCC. EPA, “2013 Revisions to the Greenhouse Gas
Reporting Rule and Final Confidentiality Determinations for New or Substantially
Revised Data Elements, FR,” 78 Federal Register 71903.
March 28, 2014
White House released the "Strategy to Reduce Methane Emissions." The Strategy
summarized the sources of methane emissions, committed to new steps to cut
emissions, and outlined the Administration’s efforts to improve the measurement of
these emissions. The Strategy proposed steps to further cut methane emissions
from landfil s, coal mining, agriculture, and oil and gas systems through both
voluntary actions and potential regulatory standards.
April 15, 2014
EPA released the Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990-2012,
which reported that U.S. GHG emissions in 2012 totaled 6,526 MMT of CO2
equivalents, of which 567.3, or about 9%, was methane.
April 15, 2014
EPA released for external peer review five technical white papers on potentially
significant sources of methane emissions in the oil and gas sector (pneumatic
devices, liquids unloading, well completions, compressors, and leak detection). The
white papers focused on technical issues covering emissions and mitigation
techniques that target methane and VOCs.
April 28, 2014
BLM released an ANPRM soliciting input on the development of a program to
capture, sell, or otherwise dispose of coalbed methane or methane gases that are
released from coal or other type of mineral seam into the air during extraction
operations. BLM, “Waste Mine Methane Capture, Use, Sale, or Destruction,
ANPRM,” 79 Federal Register 23923.
April 27, 2014
DOE hosted a roundtable under the CAP with representatives of labor and
manufacturing organizations to discuss methane emissions from the midstream and
downstream natural gas systems.
May 8, 2014
EPA proposed the "Gas STAR Gold" initiative, a program to certify oil and gas
facilities that reduce emissions of methane.
May 20, 2014
DOE hosted a roundtable under the CAP with scientists and representatives from
environmental groups and other nongovernmental organizations to discuss methane
emissions from the natural gas sector.
July 17, 2014
EPA released a Proposed Rule that updated the standards of performance for new
municipal solid waste landfil s. The proposed limits for new landfil s would require
operators to capture two-thirds of their methane and air toxics emissions by 2023.
EPA, “Standards of Performance for Municipal Solid Waste Landfil s,” 79 Federal
Register
41795. EPA released an ANPRM soliciting input on methods to reduce
methane and other emissions from existing municipal solid waste landfil s. EPA,
“Emission Guidelines and Compliance Times for Municipal Solid Waste Landfil s,”
Advance Notice of Proposed Rulemaking, 79 Federal Register 41772.
July 25, 2014
EPA’s Office of Inspector General (OIG) released a report that stated that EPA “has
placed little focus and attention on reducing methane emissions from pipelines in the
natural gas distribution sector.” EPA OIG, "Improvements Needed in EPA Efforts to
Address Methane Emissions From Natural Gas Distribution Pipelines," Report No.
14-P-0324.
July 29, 2014
DOE announced a series of steps aimed at reducing methane emissions from natural
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Methane: An Introduction to Emission Sources and Reduction Strategies

gas transmission and distribution systems, including setting energy efficiency rules
for new natural gas compressors and working with industry on research and
development to improve natural gas system efficiency and reduce leaks. DOE,
"Factsheet: An Initiative to Help Modernize Natural Gas Transmission and
Distribution Infrastructure."
July 31, 2014
USDA released guidance for calculating GHG emissions from agriculture and
forestry activities, part of its larger efforts to address agriculture’s potential effects
on climate change. USDA, “Quantifying Greenhouse Gas Fluxes in Agriculture and
Forestry: Methods for Entity-Scale Inventory.”
August 1, 2014
USDA, DOE, and EPA released the "Biogas Opportunities Roadmap: Voluntary
Actions to Reduce Methane Emissions and Increase Energy Independence,” a
comprehensive list of programs, funding opportunities, and strategies to increase
construction and use of methane-fed biogas reactors in the agriculture, wastewater
treatment, landfil , and other sectors in part as a way to create a market for use of
the gas.
November 24, 2014
BLM’s Notice of Proposed Rulemaking for Onshore Oil and Gas Order 9, Waste
Prevention and Use of Produced Oil and Gas for Beneficial Purposes, is placed on
the Fall 2014 Unified Agenda with an April 2015 date for the NPRM and an April
2016 date for final action.
December 9, 2014
EPA proposed amendments to subpart W of the Greenhouse Gas Reporting
Program that would add reporting of GHG emissions from gathering and boosting
systems, completions and workovers of oil wells using hydraulic fracturing, and
blowdowns of natural gas transmission pipelines. EPA, “Greenhouse Gas Reporting
Rule: 2015 Revisions and Confidentiality Determinations for Petroleum and Natural
Gas Systems; Proposed Rule,” 79 Federal Register 73148.
December 16, 2014
DOE’s Advanced Research Projects Agency—Energy office announced $60 mil ion
in awarded grants for cutting-edge technology that wil detect, locate, and measure
methane emissions, among other initiatives.
January 14, 2015
EPA announced a series of steps the agency plans to take in 2015 to address
methane emissions from the oil and gas sector, including (1) building on the 2012
NSPS for VOCs to address new and modified activities and equipment in the sector
uncovered by the previous rule, (2) extending VOC reduction requirements to
existing oil and gas sources in ozone nonattainment areas and states in the Ozone
Transport Region (in the form of Control Techniques Guidelines, which states
would need to address in their State Implementation Plans), and (3) expanding
voluntary efforts under the Natural Gas STAR program.
April 16, 2015
The Federal Energy Regulatory Commission released a policy statement, “Cost
Recovery Mechanisms for Modernization of Natural Gas Facilities,” which would
allow interstate natural gas pipelines to recover the costs of modernizing their
facilities and infrastructure to enhance the efficient and safe operation of their
systems.
April 21, 2015
DOE released the Quadrennial Energy Review, which called for a competitive
program that would provide financial assistance to states to help speed replacement
of old natural gas distribution lines. The proposal envisioned “targeted funding to
offset incremental costs to low income households, and funding for enhanced direct
inspection and maintenance programs,” with an estimated costs of $2.5 bil ion to
$3.5 bil ion over 10 years.
April 22, 2015
DOJ, in a settlement with the natural gas company Noble Energy over alleged Clean
Air Act violations, set a precedent for a “basin-wide” approach to curbing emissions
from energy extraction, an approach that some believe would aid regulators in
implementing further EPA rules regulating methane.
July 13, 2015
BLM released proposed, updated regulations to its Order 3 rulemaking to ensure
accurate measurement, accountability, and royalty payments for oil and gas
production from federal and Indian leases aimed at preventing theft and loss of the
resources. Public comment on the rule ran through September 11, 2015. BLM,
Congressional Research Service
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Methane: An Introduction to Emission Sources and Reduction Strategies

"Onshore Oil and Gas Operations; Federal and Indian Oil and Gas Leases; Site
Security," Proposed Rule, 80 Federal Register 40767.
July 23, 2015
EPA released its proposed framework for a revised Natural Gas STAR program for
voluntary cuts in methane emissions from existing sources, proposing a program
that the agency says included more flexibility for industry, such as company-wide
options, than the facility-based approach that the agency was forced to withdraw
last year in the face of industry opposition.
August 14, 2015
EPA released a proposed supplement to the 2014 proposed NSPS for new municipal
solid waste landfil s, “Standards of Performance for Municipal Solid Waste Landfil s,”
and a proposed rule for existing municipal landfil s, “Emission Guidelines and
Compliance Times for Municipal Solid Waste Landfil s.” The proposals would set an
emissions threshold of 34 metric tons of methane, a level at which landfil s would be
required to begin capturing emissions of landfil gas, which contains methane and
other pol utants. The figure is lower than a 40-ton threshold EPA proposed in 2014
as well as the current NSPS threshold of 50 metric tons.
August 18, 2015
EPA released proposed rules for the oil and gas industry, including (1) proposed
updates to the 2012 NSPS that would set methane and VOC requirements for
additional new and modified sources in the oil and gas industry; (2) Draft Control
Techniques Guidelines, which would target VOC emissions from existing oil and gas
sources in certain ozone nonattainment areas and states in the Ozone Transport
Region; (3) a proposed source determination rule, which would clarify EPA’s air
permitting requirements as they apply to the oil and natural gas industry; and (4) a
proposed Federal Implementation Plan for EPA’s Indian Country Minor New Source
Review program for oil and gas production sources.
September 21, 2015
BLM sent its proposal to update standards to reduce venting and flaring from oil and
gas production on federal lands to OMB for review.
Source: CRS.
Note: Initiatives were selected based upon CRS’s consideration of significance.

Author Contact Information

Richard K. Lattanzio, Coordinator
James E. McCarthy
Analyst in Environmental Policy
Specialist in Environmental Policy
rlattanzio@crs.loc.gov, 7-1754
jmccarthy@crs.loc.gov, 7-7225
Kelsi Bracmort
Lynn J. Cunningham
Specialist in Agricultural Conservation and Natural
Information Research Specialist
Resources Policy
lcunningham@crs.loc.gov, 7-8971
kbracmort@crs.loc.gov, 7-7283

Acknowledgments
This report was originally co-authored by Anthony Andrews, former CRS Specialist in Energy Policy. The
current authors would also like to thank Amber Hope Wilhelm, Graphics Specialist, CRS; and James Kidd,
Editor, CRS.
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