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
Anthony Andrews
Specialist in Energy Policy
James E. McCarthy
Specialist in Environmental Policy
Lynn J. Cunningham
Information Research Specialist
January 14, 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†(Strategy). The Strategy, released on March 28, 2014, commits to new steps
to cut emissions through both voluntary actions and proposed rulemaking, and outlines 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 increased controls. They argue that further
regulation of emissions would be either untenable from an economic standpoint or ineffective at
providing significant health and environmental benefits. They contend that industries 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. Some U.S. lawmakers support these viewpoints, and have
proposed legislation to roll back the federal initiatives.
Health and environmental advocates, however, contend that the Strategy falls short. They argue
that methane emissions can jeopardize worker safety, lead to ground-level ozone formation
(commonly referred to as “smogâ€), 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. Some U.S. lawmakers agree, and they have proposed new controls or
pushed for federal agencies to more fully regulate methane emissions.
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, the federal government has sought policies to help reduce, capture, and reuse
methane emissions as far back as the 1970s. 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
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Methane: An Introduction to Emission Sources and Reduction Strategies
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 have the potential to 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 rules: one on new municipal landfills and another on federal oil and gas leases. The
Obama Administration’s recent Strategy—as well as a variety of recent proposals in Congress—
attests 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 .......................................................................................................... 7
The Obama Administration’s Strategy to Reduce Methane Emissions ............................... 7
Methane: A Primer ........................................................................................................................... 9
Emissions ................................................................................................................................. 10
Historical Trends ..................................................................................................................... 11
Source Sectors and Mitigation Activities ................................................................................ 14
Agriculture Sector ............................................................................................................. 14
Fossil Energy Sector .......................................................................................................... 16
Waste Management Sector ................................................................................................ 20
Issues in Measurement ............................................................................................................ 22
Conclusion ..................................................................................................................................... 25
Figures
Figure 1. U.S. Methane Emissions: Sources .................................................................................. 11
Figure 2. U.S. Methane Emissions: Historical Trends by Source Sector ....................................... 12
Figure 3. U.S. Methane Emissions: Historical Trends by Source Category .................................. 13
Figure 4. Natural Gas Industry Sectors .......................................................................................... 18
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 ........................................................................ 36
Contacts
Author Contact Information........................................................................................................... 38
Acknowledgments ......................................................................................................................... 38
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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., oil and coal). 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, and less sulfur dioxide and nitrogen oxide, on average, 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 coal-bed 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, 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. See Energy
Information Administration (EIA), Office of Oil and Gas. Carbon Monoxide: derived from EIA, Emissions of
Greenhouse Gases in the United States 2009. Other pollutants derived from U.S. Environmental Protection Agency,
Compilation of Air Pollutant Emission Factors, Vol. 1, Stationary Point and Area Sources, 1998.
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 that 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. Coal-bed 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. For these reasons, many in both the public and private sector
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.6 This position has been supported by many
members of Congress as well as the Obama Administration.7
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 (OSHA)
lists methane as both an asphyxiant and an explosive, as increased concentrations in local settings
can jeopardize worker safety.8 Further, the U.S. Environmental Protection Agency (EPA)
classifies methane as both a precursor to ground-level ozone formation9 (commonly referred to as
“smogâ€) and a potent greenhouse gas (GHG), albeit with a shorter atmospheric life than CO2.10
Methane’s effect on climate change is up to 34 times greater than that of CO2 when considered
over a 100-year time period, and even greater when considered over the first 20 years after it is
emitted.11 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 by-products that can be recovered and sold at market may be able to offset the
cost of their capture. Further, the value of these recovered products during oil and gas extraction
would contribute to increased royalty payments to state and federal governments.
6 Ernest J. Moniz et al., The Future of Natural Gas: An Interdisciplinary MIT Study, June 25, 2010.
7 Support for natural gas production has come from the Obama White House. 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.
8 U.S. Department of Labor, Occupational Safety and Health Administration (OSHA), Chemical Sampling Information,
Methane.
9 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 U.S. Environmental Protection Agency, Regulatory Impact Analysis: Final National Ambient Air
Quality Standards for Ozone, Research Triangle Park, NC, 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.â€
10 As a greenhouse gas (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.
11 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.â€
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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.12 Efforts to capture
or abate these emissions are generally more difficult and costly than for other pollutants. Whether
or not 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 by-product 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 utilize 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
12 Like methane, volatile organic compounds (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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programs for research and technology development, voluntary guidelines and tax incentives for
industry, and/or rules for mineral rights lessees on federal lands.
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
methane emissions could serve the co-benefit of aiding in the reduction of other pollutants,
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.13 At the federal
level, two methane-emitting source categories are addressed directly by regulations. They include
(1) EPA’s 1996 standards on municipal landfills,14 and (2) the Bureau of Land Management’s
(BLM’s) 1980 notice on venting and flaring for oil and gas leases on federal lands.15 However,
many emission sources in the oil and gas industry, as well as many activities in the agricultural
and waste management sectors, remain uncovered by any regulatory standard. For this reason,
some U.S. lawmakers have proposed controls and/or have pushed for federal agencies to more
fully regulate methane emissions.
EPA has the authority to regulate methane emissions as both an ozone precursor and a GHG
under the Clean Air Act (CAA).16 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.17 The agency’s
authority to regulate methane as a GHG has been upheld by the Supreme Court’s 2007 decision in
Massachusetts v. EPA18 which determined that GHGs fall under the definition of “air pollutant†as
13 See discussion under section “Fossil Energy Sector.â€
14 U.S. Environmental Protection Agency, “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.â€
15 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.
16 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.
17 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
U.S. Environmental Protection Agency, Conversion Factors for Hydrocarbon Emission Components, Washington, DC,
EPA-420-R-10-015, July 2010.
18 Massachusetts v. EPA, 549 U.S. 497 (2007).
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used in the CAA. Following this decision, EPA determined that six GHGs, including methane,
endangered public health and welfare,19 and issued several rules to control GHGs focused
primarily on CO2.20 The Administration has been pressured by many health and environmental
organizations to promulgate performance standards specific to methane emissions. However, to
this point, EPA has not advanced such standards. The agency maintains that existing rules set on
other air pollutants commonly co-emitted with methane (e.g., VOCs) as well as its voluntary
programs with industry have adequately returned cost-effective reductions in emissions.21 In
addition to EPA, 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.
Current and proposed initiatives—including the Obama Administration’s 2014 “Strategy to
Reduce Methane Emissionsâ€â€”are discussed in further detail in the remainder of this report.
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
untenable from an economic standpoint or ineffective at providing significant health and
environmental benefits. They contend that industries 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.
Some U.S. lawmakers have supported these viewpoints.
Efforts by the federal government to incentivize the reduction, capture, and reuse of methane
emissions 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
19 U.S. Environmental Protection Agency, “Endangerment and Cause or Contribute Findings for Greenhouse Gases,â€
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.
20 For example, U.S. Environmental Protection Agency 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 U.S. Environmental Protection Agency,
“Carbon Pollution Emission Guidelines for Existing Stationary Sources: Electric Utility Generating Units; Proposed
Rule,†79 Federal Register 34829, June 18, 2014.
21 While the 1996 landfill standards are the only EPA rulemaking that specifically targets methane, many performance
standards set on facilities for other air pollutants can have the co-benefit of reducing methane emissions. One example
is EPA’s August 2012 New Source Performance Standards (NSPS) for the “Crude Oil and Natural Gas Productionâ€
and the “Natural Gas Transmission and Storage†source categories. The NSPS regulate volatile organic compound
(VOC) emissions from gas wells, compressors, and other equipment. See U.S. Environmental Protection Agency, “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. For a summary of the NSPS, see CRS
Report R42833, Air Quality Issues in Natural Gas Systems, by Richard K. Lattanzio.
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use of the recovered gas dates back, at least, to the 94th Congress.22 Similar bills targeting
emissions from coal mines and municipal landfills were introduced in the 96th and 97th
Congresses, respectively.23 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.â€24 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.â€25 Methane reduction was also included
as a qualifying activity in market-based GHG control proposals as far back as the 101st
Congress.26
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 as well as
revoking it. Recent bills and amendments have proposed several different policy tools as
strategies for reduction. They include (1) providing economic incentives (e.g., through tax
benefits) for activities that capture and use fugitive gas (e.g., H.R. 860, the Biogas Investment Tax
Credit Act of 2013), (2) authorizing the Administration or a specific agency to investigate or
directly regulate methane emissions (e.g., H.Amdt. 507 to H.R. 2728 sought to allow the
Secretary of the Interior to issue regulations to reduce methane emissions from oil and gas
operations on federal and Indian lands), and (3) providing a market-based mechanism (e.g., fee)
to incentivize methane reduction (e.g., S. 332, the Climate Protection Act of 2013).
Conversely, many bills in recent Congresses have also aimed to remove the executive branch’s
authority to regulate methane emissions based predominantly on arguments for economic growth
and employment. Some examples of the most recent efforts include (1) amending the CAA to
remove “methane†and other GHGs from the definition of “air pollutant†(e.g., H.R. 3895, the
Energy Exploration and Production to Achieve National Demand Act [of 2014]), and (2)
prohibiting appropriated funds from being used by agencies to regulate methane (e.g., H.R. 621,
the Ensuring Affordable Energy Act [of 2013]).
For a selected list of recent bills and amendments that address methane, see Table A-1 of
Appendix A.
22 For example, the Family Farm Energy Conversion Act (S. 3714).
23 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) (P.L. 97-232).
24 World Environment Policy Act of 1989 (S. 201).
25 Clean Air Act Amendments of 1990 (S. 1630, P.L. 101-549). The findings were reported in U.S. Environmental
Protection Agency, 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 U.S. Environmental Protection Agency, U.S. Methane
Emissions 1990-2020: Inventories, Projections, and Opportunities for Reductions, EPA 430-R-99-013, 1999.
26 CO2 Offsets Policy Enabling Act of 1990 (H.R. 5966).
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Administrative Initiatives
Historically, many of the methane control initiatives managed by the federal government have
taken the form of either research and development programs or voluntary public-private
partnerships with industry. Federal research and development programs have provided funding
for new technologies to enable more cost-effective emission reductions across various sectors of
the economy. Offices that have provided financial and technical assistance 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; and the
Department of Transportation (DOT) Pipeline and Hazardous Materials Safety Administration, as
well as 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.27 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
operations, limited infrastructure, and uncertain investment climates. As with many voluntary
initiatives, these programs have returned mixed results.28
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).29 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, would be unattainable without significant methane controls. The
CAP set guidelines for EPA and the Departments of Agriculture, Energy, Interior, Labor, and
Transportation to develop a comprehensive interagency methane strategy,30 which was released
on March 28, 2014, under the title “Strategy to Reduce Methane Emissions†(Strategy).31
27 These programs are discussed in more detail in subsequent sections of this report.
28 For a discussion of the performance of these and other voluntary programs, see the subsequent sections of this report
on the respective industry sectors.
29 Executive Office of the President, 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.
30 EOP, CAP, op cit., p. 10.
31 Executive Office of the President, “Climate Action Plan: Strategy to Reduce Methane Emissions,†March 2014.
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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).32
2. Petroleum and Natural Gas.
• An EPA assessment of several potentially significant sources of methane and
other emissions from the oil and gas sector through a series of technical
white papers33 and a determination on how best to pursue further methane
reductions from these sources. The White House announced on January 14,
2015, that these steps would include (1) a proposal to build on a set of 2012
New Source Performance Standards (NSPS) for VOC emissions to address
new and modified activities and equipment in the sector uncovered by the
previous rule (scheduled for release in the summer of 2015), (2) extending
VOC reduction requirements to existing oil and gas sources in ozone
nonattainment areas and states in the Ozone Transport Region, and (3)
expanding voluntary efforts under the Natural Gas STAR program.34
• A BLM proposal to update standards to reduce venting and flaring from oil
and gas production on public lands (scheduled for release in April 2015).
• A Department of Transportation Pipeline and Hazardous Materials Safety
Administration (PHMSA) proposal for natural gas pipeline safety standards
(scheduled for release in 2015).
• 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).35
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).36
4. Landfills. An EPA proposal to update standards to reduce methane from new landfills, and
to take public comment on whether to update standards for existing landfills (released on
July 17, 2014).37
32 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.
33 U.S. Environmental Protection Agency, “White Papers on Methane and VOC Emissions,†April 15, 2014.
34 Executive Office of the President, “FACT SHEET: Administration Takes Steps Forward on Climate Action Plan by
Announcing Actions to Cut Methane Emissions,†January 14, 2015.
35 U.S. Department of Energy, “Factsheet: An Initiative to Help Modernize Natural Gas Transmission and Distribution
Infrastructure,†July 29, 2014.
36 U.S. Department of the Interior, Bureau of Land Management, “Waste Mine Methane Capture, Use, Sale, or
Destruction,†79 Federal Register 23923, April 28, 2014.
37 U.S. Environmental Protection Agency, “Standards of Performance for Municipal Solid Waste Landfills,†Proposed
Rule, 79 Federal Register 41807, July 17, 2014; and U.S. Environmental Protection Agency, “Emission Guidelines and
(continued...)
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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).38
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.39 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, it is commonly characterized as a “short-
lived climate forcer,†along with black carbon and various hydrofluorocarbons (HFCs).
(...continued)
Compliance Times for Municipal Solid Waste Landfills,†Advance Notice of Proposed Rulemaking, 79 Federal
Register 41772, July 17, 2014.
38 U.S. Environmental Protection Agency, Conversion Factors for Hydrocarbon Emission Components, Washington,
DC, EPA-420-R-10-015, July 2010.
39 Intergovernmental Panel on Climate Change (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. According to the current metrics used by EPA, the same amount
of methane emissions by mass is approximately 25 times more potent than CO2 emissions when averaged over a 100-
year time horizon.40 Further, methane chemically reacts in the atmosphere to produce other climate warming gases—
for example, ozone in the troposphere and water in the stratosphere. An estimate of the warming effects of these
product gases is included in the GWP of 25. However, these reactions also indirectly affect aerosols in the
atmosphere, likely further enhancing the warming effect of methane.41
As stated, methane reacts with other chemicals in the atmosphere and dissipates. Thus, while methane is a highly
potent GHG for a short period after its initial release, its capacity to trap heat dissipates after approximately 12 years.
By comparison, CO2’s 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. EPA’s most recent
Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990-2012, released in April 2014, uses the SAR GWP of 21 (and,
by extension, al of the data and graphics in this report use the SAR GWP of 21). EPA has 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).42 The AR4 lists methane’s GWP as 25 and 72 over a 100-year and a 20-year time
horizon, respectively. EPA’s 2015 Inventory will employ these GWPs. Accordingly, due to this reevaluation of climate
impacts, methane’s comparative role as a GHG will increase by approximately 20% under the new reporting. The
IPCC Fifth Assessment Report 2013 (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 official y 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.
Emissions
According to EPA, methane is the second-most prevalent GHG emitted by the United States
(behind CO2), and in 2012 it accounted for 567.3 million metric tons of CO2 equivalent, or about
9% of all domestically produced emissions from human activities.43 Some academic studies have
put these emissions even higher.44 Of the total, nearly 40% was emitted from sources in the
energy production sector, a third from sources in the agricultural sector, and a fifth from sources
in the waste management sector (see Figure 1).
40 Intergovernmental Panel on Climate Change, Climate Change 2007: The Physical Science Basis, Working Group I
Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change.
41 This description of GWP is summarized from James Bradbury et al., Clearing the Air, World Resources Institute,
April 2013, p. 11.
42 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.
43 As calculated over 100 years. U.S. Environmental Protection Agency, Inventory of U.S. Greenhouse Gas Emissions
and Sinks: 1990-2012, Washington, DC, EPA 430-R-14-003, April 15, 2014.
44 For further discussion, see section “Issues in Measurement.â€
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Figure 1. U.S. Methane Emissions: Sources
Source: Congressional Research Service, with data from the U.S. Environmental Protection Agency, Inventory of
U.S. Greenhouse Gas Emissions and Sinks: 1990-2012, Washington, DC, EPA 430-R-14-003, April 15, 2014.
Historical Trends
Between 1990 and 2012, methane emissions in the United States decreased by almost 11%.
During this time period, emissions have increased from sources associated with agricultural
activities, while emissions have decreased from sources associated with waste management and
the exploration and production of natural gas and petroleum products (see Figure 2).
Comparatively, the source categories for natural gas systems and landfills have seen the most
notable reductions over the past 20 years, and manure management the most notable increase, but
many other subcategories have seen little to no change (see Figure 3).
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Figure 2. U.S. Methane Emissions: Historical Trends by Source Sector
Source: Congressional Research Service, with data from the U.S. Environmental Protection Agency, Inventory of
U.S. Greenhouse Gas Emissions and Sinks: 1990-2012, Washington, DC, EPA 430-R-14-003, April 15, 2014.
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Figure 3. U.S. Methane Emissions: Historical Trends by Source Category
Source: Congressional Research Service, with data from the U.S. Environmental Protection Agency, Inventory of
U.S. Greenhouse Gas Emissions and Sinks: 1990-2012, Washington, DC, EPA 430-R-14-003, April 15, 2014.
Note: “Other†sources include rice cultivation, stationary 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,45
• 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 Sector46
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 by-product, 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 36% of U.S. anthropogenic methane emissions
in 2012.47 From 1990 to 2012, methane emissions from agricultural sources increased by nearly
14% (see Figure 2). Enteric fermentation is the leading source of agricultural methane emissions,
45 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, op cit.
46 This section was authored by Kelsi Bracmort, Specialist in Agricultural Conservation and Natural Resources Policy.
47 EPA, Inventory, op cit.
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as well as the leading source of methane emissions from all industry sectors. Livestock manure
management is the second-leading agricultural source (see Figure 3).
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) systems48 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).49 There are, however, some economic, operational, and safety
concerns associated with the use of AD systems.50
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.51 The Biogas Roadmap is a
deliverable of an April 2013 Memorandum of Understanding between USDA and the Innovation
Center for U.S. Dairy.52 Second, the Strategy supports the continued use of previously established
voluntary efforts (e.g., AD system deployment through assistance from numerous USDA
programs).
The Strategy’s goal is methane emission reduction, but the major agricultural source of methane
emissions—enteric fermentation—is omitted from the Strategy. Some may wonder how much
impact methane reduction from the agricultural sector can have if the major source is omitted.
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.
48 An anaerobic digestion (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.
49 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.
50 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.
51 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.
52 U.S. Department of Agriculture, “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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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
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 also may 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 like anaerobic digestion systems, and the development of voluntary
mitigation-related contracts53 could help alleviate costs and incentivize innovation. On the other
hand, it may be that expansion of mitigation technologies such as anaerobic digestion systems
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 Sector54
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. Methane emissions arise
from natural gas engine and turbine uncombusted exhaust, bleed and discharge
emissions from pneumatic devices, and fugitive emissions from system
components, as well as 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.
53 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.
54 This section was authored by Anthony Andrews, Specialist in Energy Policy, and Richard Lattanzio, Analyst in
Environmental Policy.
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The fossil energy sector constituted nearly 40% of U.S. anthropogenic methane emissions in
2012.55 From 1990 through 2012, 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 2014 Inventory, EPA
reported that methane emitted by the oil and gas sector had generally declined by 16% since
1990. However, EPA reports that it appears to be on the rise again, corresponding to increases in
domestic onshore oil and gas production.56 Methane emissions from coal mining have remained
relatively constant over the past several decades, accounting 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 2012.57
Sources of emissions in the oil and gas sector include the following:
• Upstream Production Sector. 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 Sector. 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 Sector. Emissions from leaking distribution pipelines
are most likely to occur from older pipelines. In 2012, 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 completionsâ€)58 during hydraulic fracturing, leak
detection and repair technologies at facilities and gas compressors, reduced venting of associated
gas at oil wells, and the replacement of highâ€emitting pneumatic devices. However, voluntary
adoption of control techniques has been uneven across companies and regions. Consequently, in
55 EPA, Inventory, op cit.
56 EPA, Inventory, op cit.
57 EPA, Inventory, op cit.
58 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.†U.S. Environmental Protection Agency, “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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2012, EPA promulgated emission standards for conventional pollutants (e.g., volatile organic
compounds) for the oil and gas sector through a series of New Source Performance Standards
(NSPS) and National Emissions Standards for Hazardous Air Pollutants.59 These standards have
the co-benefit of reducing methane emissions from certain new sources in some segments of the
gas industry.60 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).61 Notwithstanding,
many sources remain uncontrolled by state or federal standards.
Figure 4. Natural Gas Industry Sectors
Source: DTE Energy, Natural Gas Processing, Delivery, and Storage.
59 EPA, NSPS, op cit.
60 For further discussion, see CRS Report R42833, Air Quality Issues in Natural Gas Systems, by Richard K. Lattanzio.
61 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.
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BLM has issued rulemakings that address methane emissions on federal lands under the Mineral
Leasing Act (MLA), but do not require practices to minimize methane emissions.62 The MLA
authorizes the 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 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.â€63 This 1980
notice to operators of oil and gas leases 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 announced a series of steps it
would take in 2015 and beyond. These include the following:64
• 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 sourcesâ€65 (scheduled for release in the
summer of 2015).
• 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
(scheduled for release in the summer of 2015). These requirements would be in
the form of Control Techniques Guidelines, which states would be required to
address in their State Implementation Plans.
• An EPA proposal to expand voluntary efforts under the Natural Gas STAR
program and the Coalbed Methane Outreach Program.
• An EPA proposal to strengthen its Greenhouse Gas Reporting Program to require
reporting in all segments of the industry (released on December 9, 2014).66
• A BLM proposal to update standards to reduce venting and flaring from oil and
gas production on federal lands (scheduled for release in April 2015), and an
Advance Notice of Proposed Rulemaking (ANPRM) to develop a program for
62 Mineral Leasing Act, as amended and supplemented, 30 U.S.C. 181 et seq. For a summary of the MLA and BLM’s
leasing activities, see BLM’s website and CRS Report R40806, Energy Projects on Federal Lands: Leasing and
Authorization, by Adam Vann.
63 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.
64 Executive Office of the President, “Fact Sheet: Administration Takes Steps Forward on Climate Action Plan by
Announcing Actions to Cut Methane Emissions,†January 14, 2015.
65 EOP, Fact Sheet, op cit. For a discussion of the source categories under consideration, see U.S. Environmental
Protection Agency, “White Papers on Methane and VOC Emissions,†April 15, 2014, http://www.epa.gov/airquality/
oilandgas/whitepapers.html.
66 U.S. Environmental Protection Agency, “Greenhouse Gas Reporting Rule: 2015 Revisions and Confidentiality
Determinations for Petroleum and Natural Gas Systems; Proposed Rule,†79 Federal Register 73148, December 9,
2014.
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the capture and sale, or disposal, of waste mine methane on lands leased by the
federal government (released on April 28, 2014).67
• A Department of Transportation Pipeline and Hazardous Materials Safety
Administration (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.â€68
Many of these steps have yet to be proposed or are still in the very early stages of proposed
rulemaking. Thus, many of the requirements have yet to be specified.
Waste Management Sector69
Waste management sources of methane emissions include the following:
• Landfills. Landfill gas—a mixture of roughly 50% methane and 50% CO2, and
including 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 is generally 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.
67 U.S. Department of the Interior, Bureau of Land Management, “Waste Mine Methane Capture, Use, Sale, or
Destruction,†79 Federal Register 23923, April 28, 2014.
68 EOP, Fact Sheet, op cit. For more discussion, see U.S. Department of Energy, “Factsheet: An Initiative to Help
Modernize Natural Gas Transmission and Distribution Infrastructure.â€
69 This section was authored by James E. McCarthy, Specialist in Environmental Policy.
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• 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 2012. Landfills accounted for approximately 18% of total U.S.
anthropogenic methane emissions in 2012, the third-largest contribution of any methane source in
the United States. Their methane emissions totaled 102.8 million metric tons of CO2 equivalents,
1.6% of total U.S. GHG emissions (see Figure 1).70 Although substantial, methane emissions
from landfills have declined 31% in recent years from a high of 149.3 million metric tons (MMT)
in 1992 (see Figure 3). Additionally, wastewater treatment and composting of organic waste
accounted for 2.2% 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
after a landfill cell has been capped. A 1996 CAA regulation known as the “Landfill Gas Ruleâ€
established New Source Performance Standards and Guidelines that require landfills with a 2.5-
million-metric-ton design capacity that accepted waste after November 8, 1987, to capture and
burn the gas. The gas can either be flared or used for energy production—often it is used as fuel
for electricity generation. In promulgating the 1996 rule, EPA said that the 2.5-million-metric-ton
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 636 operational
methane capture projects at landfills as of January 2014.71 This represents roughly one-third of
the 1,800 to 1,900 operational municipal solid waste landfills reported in operation by EPA.72
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 President’s Climate Action Plan and the March 2014 methane Strategy
document, EPA is in the process of reviewing the 1996 Landfill Gas Rule and Guideline. On June
30, 2014, the agency released a proposed revision to the NSPS for new and modified landfills and
an ANPRM for existing landfills. EPA is under a consent decree to issue a final NSPS rule by
March 30, 2015. 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 million metric tons of design
70 EPA, Inventory, op cit.
71 U.S. Environmental Protection Agency, Landfill Methane Outreach Program, Energy Projects and Candidate
Landfills, http://www.epa.gov/lmop/projects-candidates/index.html.
72 Slightly different estimates of the number of operational MSW landfills were presented at various points in EPA’s
July 2014 Advance Notice of Proposed Rulemaking (ANPRM) for existing MSW landfills. See U.S. Environmental
Protection Agency, “Emission Guidelines and Compliance Times for Municipal Solid Waste Landfills,†Advance
Notice of Proposed Rulemaking, 79 Federal Register 41778, July 17, 2014.
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capacity (or 2.5 million cubic meters of waste). The agency explains this decision by stating the
following in the preamble to the proposed rule:
[T]he cost burden for installing a collection and control system is more significant for small
landfills, which are more often owned by small entities, than larger landfills. Certain costs to
construct the gas collection system (e.g., flat fees for drill rig mobilization, and monitoring
and construction costs) remain relatively constant regardless of the size of the landfill.
For these reasons, the EPA is not proposing any changes to the current design capacity
threshold of 2.5 million Mg [metric tons] and 2.5 million m3 [cubic meters].73
But the proposed rule would require that a gas collection control system be installed and
operational within 30 months after landfill gas emissions reach 40 metric tons of nonmethane
organic compounds or more per year. Under the current NSPS, this threshold is 50 metric tons per
year.
EPA expects few landfills to be affected by the proposed rule: according to an agency fact sheet,
“EPA estimates that 17 new landfills would be subject to the proposed updated standards;
however, only 11 would be required to install controls by 2023, based on their projected
emissions.â€74 The proposed standard would apply to a much smaller percentage of landfills than
would the standard established in 2010 by the California Air Resources Board: that state standard,
while structured differently, applies to any landfill with 450,000 or more tons of waste in place.
For existing landfills, EPA has not yet proposed revisions to the 1996 guideline. Rather, the
agency has asked for “public input on methods to reduce emissions from existing municipal solid
waste (MSW) landfills,†and stated that it “intends to consider the information received in
response to the ANPRM in evaluating whether additional changes beyond those in the proposed
revisions for new sources are warranted.â€75
Issues in Measurement76
Unlike CO2, where emissions are reported using well-tracked energy statistics,77 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 those which are diffuse, transitory, and elusive to capture. 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
73 U.S. Environmental Protection Agency, “Standards of Performance for Municipal Solid Waste Landfills,†Proposed
Rule, 79 Federal Register 41807, July 17, 2014.
74 U.S. Environmental Protection Agency, “Proposed Updates to the New Source Performance Standards for Municipal
Solid Waste Landfills,†fact sheet.
75 U.S. Environmental Protection Agency, “Emission Guidelines and Compliance Times for Municipal Solid Waste
Landfills,†Advance Notice of Proposed Rulemaking, 79 Federal Register 41772, July 17, 2014.
76 This section was authored by Richard Lattanzio, Analyst in Environmental Policy.
77 According to EPA’s Inventory, over 94% of CO2 emissions in 2012 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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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
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
operationâ€; 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.78 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 IPCC79 and supplemented with additional domestic
78 EPA, Inventory, op cit.
79 Intergovernmental Panel on Climate Change, 2006 IPCC Guidelines for National Greenhouse Gas Inventories.
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information, where available.80 Bottom-up methodologies are used also for EPA’s Greenhouse
Gas Reporting Program,81 as well as the Energy Information Administration’s (EIA’s) Natural
Gas Annual.82 Further, there are many examples of state,83 local, and nongovernmental
inventories84 commissioned by a range of stakeholders, from regional and municipal agencies to
community groups and academic institutions.
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 (e.g., 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 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;85 a 2013 paper published by Harvard University researchers and federal scientists
suggests that EPA’s figures may be underestimated in some cases by as much as 50%;86 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).87
80 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 (CEFM); and the Gas Research Institute and U.S.
Environmental Protection Agency, 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.
81 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, http://www.epa.gov/ghgreporting/.
82 U.S. Energy Information Administration, Natural Gas Annual (various years).
83 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 press
release, “State to undertake major study on oil and gas emissions,†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.
84 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, September 16, 2013). For more information, see Environmental Defense Fund’s Methane Leakage Study,
http://www.edf.org/methaneleakage.
85 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, accepted
for publication, 2014.
86 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, November 25, 2013.
87 Adam Brandt, et al., “Methane Leaks from North American Natural Gas Systems,†Science, 343:6172, pp. 733-735,
February 14, 2014.
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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.88 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 NOAA,89 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.90 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.
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 or not a given control strategy is effective and cost-efficient for a
given industry has depended 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 (e.g., 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 an 11% decrease over the past
two decades, the source categories that have contributed to these reductions are few (i.e., landfills
and natural gas production). 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 may confront greater challenges. They may lack adequately demonstrated
control technologies or cost-effective opportunities. They may not co-emit other air pollutants,
and thus may lack the “co-benefits†of existing regulations. Some of these sources have seen
88 EOP, Strategy, op cit., pp. 11-14.
89 The President’s FY2015 budget requests $8 million above current funding of $6.5 million for this program.
90 U.S. Environmental Protection Agency, 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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Methane: An Introduction to Emission Sources and Reduction Strategies
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 economic, environmental, and public
health and safety concerns?
4. To what extent may recently promulgated and proposed rulemaking for air
pollutants commonly co-emitted with methane also serve the co-benefit of
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)?
5. 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?
6. 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? Do
fluctuations in the market price of natural gas impact the choice of policy?
7. How should the burden of GHG reductions be distributed among the various
GHG emissions sources, and how should methane’s other environmental benefits
(in comparison to oil and coal combustion) be weighed in this context?
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Methane: An Introduction to Emission Sources and Reduction Strategies
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
113 H.R.
3895
Energy
Rep. Duncan, 2/12/2014:
The bill would have aimed to
Exploration
Jeff
referred to
reduce or eliminate financial,
(H.R. 4286,
and Production
House
regulatory, and technical barriers to
H.R. 4304,
to Achieve
subcommittee.
energy exploration and production.
and S. 2170
National
It would have amended Section
include
Demand Act
302(g) of the CAA (42 U.S.C.
similar
7602(g)) by adding “The term ‘air
provisions.)
pol utant' does not include carbon
dioxide, water vapor, methane,
nitrous oxide, hydrofluorocarbons,
perfluorocarbons, or sulfur
hexafluoride."
113 H.R.
3547 Consolidated Rep. Smith,
1/17/2014:
The bill 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 carbon
dioxide, 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 bill 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
drilling operations on public lands.
vote: 190-230
(Rol no. 601).
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. 1943
SUPER Act of
Rep. Peters,
5/10/2013:
The bill would have required the
2013
Scott H.
referred to
President to establish a Task Force
House
on short-lived climate pollutants
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
will be minimized before such
vote: 183-233
application can be considered for
(Rol no. 605).
approval.
113 H.R.
621 Ensuring
Rep. Poe,
2/15/2013:
The bill would have prohibited any
Affordable
Ted
referred to
funds appropriated or otherwise
Energy Act
House
available for the Administrator of
subcommittee.
EPA 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 bill 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
carbon dioxide, 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.
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.
2940 American Sen.
11/19/2014:
The bill 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 carbon dioxide
emissions; and (2) emissions of any
greenhouse gas, including methane,
from any greenhouse gas emission
source. The bill would have
established, implemented, and
reported on a program to col ect
data on methane emissions by
major nonnatural sources, including
emissions attributable to the
extraction and distribution of coal,
petroleum products, and natural
gas.
113 S.
2911 Super
Sen. Murphy,
9/18/2014:
The bill would have established a
Pol utants Act
Chris, and
referred to
task force to review policies and
of 2014
Sen. Collins,
Senate
measures to promote, and to
Susan
committee.
develop best practices for,
reduction of short-lived climate
pollutants including methane.
113 S.
2739 Biogas
Sen.
7/13/2014:
The bill would have amended the
Investment Tax Schumer,
referred to
Internal Revenue Code to allow for
(H.R. 860
Credit Act of
Charles
Senate
an energy tax credit through 2018
includes
2014
committee.
for investment in qualified biogas
similar
property, among other things.
provisions.)
Eligible qualified biogas property
was defined as including systems
which 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 bill 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 bill was
introduced in the 112th Congress as
S. 3443.
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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.
332
Climate
Sen. Sanders,
2/14/2013:
The bill would have required the
Protection Act
Bernard
referred to
Administrator of EPA to impose a
of 2013
Senate
fee on any manufacturer, producer,
committee.
or importer of a GHG pol uting
substance, and to 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 bill 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 which 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.
112 H.R.
2055 Consolidated Rep.
12/23/2011:
The bill 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 carbon dioxide, 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 bill would have suspended,
America’s
Shelley
referred to
during the two-year period
(S. 231 and
Energy and
Moore
House
beginning on the date of enactment
S.Amdt. 215
Manufacturing
subcommittee.
of the act, any EPA action under
to S. 493
Jobs Act of
the CAA with respect to carbon
include
2011
dioxide or methane pursuant to
similar
certain proceedings, other than
provisions.)
with respect to motor vehicle
emissions.
112 H.R.
153 Ensuring
Rep. Poe,
2/1/2011:
The bill would have prohibited any
Affordable
Ted
referred to
funds appropriated or otherwise
Energy Act
House
available for the Administrator of
subcommittee.
the EPA 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.
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.
97 Free Industry
Rep.
2/1/2011:
The bill would have amended
Act
Blackburn,
referred to
Section 302(g) of the CAA (42
(H.R. 1023,
Marsha
House
U.S.C. 7602(g)) by adding “The
H.R. 1287,
subcommittee.
term ‘air pollutant' does not include
H.R. 1292,
carbon dioxide, water vapor,
H.R. 1777,
methane, nitrous oxide,
H.R. 3400,
hydrofluorocarbons,
H.R. 4301, S.
perfluorocarbons, or sulfur
706, S. 1720,
hexafluoride." Some similar bills
S. 2199, and
focused solely on the exclusion of
S. 2365
agricultural emissions.
include
similar
provisions.)
112
S. 3443
Robert C. Byrd Sen.
7/25/2012:
The bill 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.
111 H.R.
6511 Ensuring
Rep. Poe,
12/9/2010:
The bill would have prohibited any
Affordable
Ted
referred to
funds appropriated or otherwise
Energy Act
House
available for the Administrator of
committee.
EPA 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 bill would have suspended,
Source
Nick J., II
referred to
during the two-year period
(S. 3072
Regulations
House
beginning on the date of enactment
includes
Delay Act
committee.
of the act, any EPA action under
similar
the CAA with respect to carbon
provisions.)
dioxide or methane pursuant to
certain proceedings, other than
with respect to motor vehicle
emissions.
Congressional Research Service
31
Methane: An Introduction to Emission Sources and Reduction Strategies
Cong.
Bill No.
Bill Title
Sponsor
Last Action
Methane Component
111
H.R. 3598
Energy and
Rep. Gordon, 12/1/2009:
The bill 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,
coal bed methane, and mining
activities, among others.
111 H.R.
3534 Consolidated Rep. Rahall,
7/30/2010:
The bill, 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 (Roll
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) 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
bill as reported or engrossed in the
House or placed on the Senate
calendar.)
Congressional Research Service
32
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 bill 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 pollution, transitioning to
recorded vote:
a clean energy economy, and
219-212 (Rol
providing for agriculture and
no. 477).
forestry related offsets. The bill
7/7/2009:
would have required the
placed on
Administrator of EPA to establish a
Senate
cap-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
landfill 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 bill would
have explicitly exempted
agriculture from the cap-and-trade
program.
111 H.R.
1426 To amend the
Rep. Lucas,
3/12/2009:
The bill would have amended the
Clean Air Act
Frank D.
referred to
CAA to prohibit the issuance of
(S. 527
to prohibit the
House
permits under Title V of that act
includes
issuance of
subcommittee.
for any carbon dioxide, nitrogen
similar
permits under
oxide, water vapor, or methane
provisions.)
title V of that
emissions resulting from biological
Act for certain
processes associated with livestock
emissions from
production.
agricultural
production
111 H.R.
1158 Biogas
Rep. Higgins,
2/24/2009:
The bill 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.
Congressional Research Service
33
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 bill 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 coal bed 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 bill 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 pollutant' 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 bills
focused on this definition solely
with respect to agricultural
emissions.
111
S. 2729
Clean Energy
Sen.
11/4/2009:
The bill 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 bill would have required
the Secretary of Agriculture and
the Administrator of EPA 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, landfills, 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 bill 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 bill
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.
Congressional Research Service
34
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 bill 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 bill would have
Calendar under
required the Administrator of EPA
General
to establish a cap-and-trade system
Orders.
for GHG emissions. Methane was
defined as a GHG, given a GWP of
25, and included in the offset
program. Eligible offset activity
included methane collection and
combustion projects at active
underground coal mines, landfills,
oil and natural gas systems, and
manure management and biogas
facilities.
111 S.
1462 American Sen.
7/16/2009:
The bill 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
pull gases from landfills and
separate out methane.
Source: Congressional Research Service.
Notes: This section was prepared with the assistance of Lynn J. Cunningham, Information Research Specialist.
The table lists only those bills that specifically mention “methane.†Bills are ordered by Congress, split between
the House and the Senate, and arranged by bill number starting with the most recent. If similar language is
contained in different bills, the first bill introduced is presented in the table (with the subsequent bil numbers
given in parentheses).
Congressional Research Service
35
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 Global Warming Potential 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 landfills, 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 mil ion metric tons
of carbon dioxide equivalents, of which 567.3 MMTCO2e, or about 9%, was
methane.
April 15, 2014
EPA released for external peer review five technical white papers on potential y
significant sources of methane emissions in the oil and gas sector (pneumatic
devices, liquids unloading, wel completions, compressors, and leak detection). The
white papers focused on technical issues covering emissions and mitigation
techniques that target methane and volatile organic compounds (VOCs).
April 28, 2014
BLM released an Advance Notice of Proposed Rulemaking (ANPRM) soliciting input
on the development of a program to capture, sell, or otherwise dispose of coal-bed
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 (PR) that updated the standards of performance for
new municipal solid waste landfil s. The proposed limits for new landfills would
require operators to capture two-thirds of their methane and air toxics emissions
by 2023. EPA, “Standards of Performance for Municipal Solid Waste Landfills,†79
Federal Register 41795. EPA released an ANPRM soliciting input on methods to
reduce methane and other emissions from existing municipal solid waste (MSW)
landfills. EPA, “Emission Guidelines and Compliance Times for Municipal Solid
Waste Landfills,†Advance Notice of Proposed Rulemaking, 79 Federal Register
41772.
Congressional Research Service
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Methane: An Introduction to Emission Sources and Reduction Strategies
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
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.â€
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, landfill, and other sectors in part as a way to create a market for use of
the gas.
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 million
in awarded grants for cutting-edge technology that will 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.
Source: Congressional Research Service.
Note: Initiatives were selected based upon CRS’s consideration of significance.
Congressional Research Service
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Methane: An Introduction to Emission Sources and Reduction Strategies
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
Anthony Andrews
Specialist in Energy Policy
aandrews@crs.loc.gov, 7-6843
Acknowledgments
The authors would like to thank Amber Wilhelm of CRS for her assistance with graphics and Bryan
Sinquefield of CRS for his assistance with editing.
Congressional Research Service
38