Landfill Gas Emissions Model (LandGEM)

Estimates emission rates from municipal solid waste landfills

The Landfill Gas Emissions Model (LandGEM) is used to estimate emission rates for total landfill gas, methane, carbon dioxide, nonmethane organic compounds, and individual air pollutants from municipal solid waste (MSW) landfills.

Landfill owners and operators can use LandGEM to determine if a landfill is subject to the control requirements of the federal New Source Performance Standards for new municipal solid waste landfills (40 CFR 60 Subpart XXX), the federal Emission Guidelines for existing municipal solid waste landfills (40 CFR Subpart CC), or the National Emission Standards for Hazardous Air Pollutants (NESHAP) for MSW landfills (40 CFR Subpart AAAA).

This tool can use site-specific data to estimate emissions or it can use default parameters if no site-specific data are available.

Software, Compatibility, and Manuals

The LandGEM is a macro-enabled Microsoft Excel file (.xlsm) that utilizes visual basic for applications (VBA) processes to function. It has been tested on systems running Microsoft Office 2007 and more recent versions. Earlier versions of Excel have not been evaluated and may no longer be compatible. For more information on required software settings, refer to the Version 3.1 User's Guide or contact us using the link under Technical Support.

Software and Manual Downloads

For a link to download the tool and user manual, please visit the following EPA Science Inventory page:

Landfill Gas Emissions Model (LandGEM)

Citation: Krause, M. AND S. Thorneloe. Landfill Gas Emissions Model (LandGEM) Version 3.1 User Manual and Tool. U.S. EPA Office of Research and Development, Washington, DC, EPA/600/B-24/160, 2024.

Background

Air emissions from landfills come from landfill gas generated by the decomposition of waste in the landfill. Landfill gas is assumed by this model to be roughly half methane and half carbon dioxide with additional, relatively low, concentrations of other air pollutants.

Emission rates at a landfill may be affected by the following:

• Waste design capacity of the landfill,
• Amount of waste-in-place in the landfill or the annual waste acceptance rate for the landfill,
• Methane generation rate,
• Potential methane generation capacity,
• Concentration of total nonmethane organic compounds and speciated nonmethane organic compounds found in the landfill gas,
• Number of years the landfill has been in operation, and
• Whether the landfill has been used for disposal of hazardous waste (co-disposal).

The EPA has determined that emissions from municipal solid waste landfills cause, or contribute significantly to, air pollution that may reasonably be anticipated to endanger public health or welfare. Some nonmethane organic compounds are known or suspected carcinogens, or cause other noncancer health effects. Public welfare concerns include the odor nuisance from the landfill gas and the potential for methane migration, both on-site and off-site, which may lead to explosions or fires. The methane emitted from landfills is also a concern because it is a greenhouse gas and contributes to global climate change.

Related Resources

• New Source Performance Standards for New Municipal Solid Waste Landfills
• Municipal Solid Waste Landfills: National Emissions Standards for Hazardous Air Pollutants (NESHAP)
• Resources, Waste and Climate Change

Technical Support

For comments or questions, email CESER@epa.gov.