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Greenhouse Gas Emissions

Stakeholder Webinar: Waste Sector Data and Methodology in the U.S. Greenhouse Gas Inventory

EPA develops an annual report called the Inventory of U.S. Greenhouse Gas Emissions and Sinks (Inventory). This report tracks total annual U.S. emissions and removals by source, economic sector, and greenhouse gas going back to 1990. One sector in the annual report is the waste sector, which includes municipal solid waste (MSW) landfills, industrial landfills, composting, and wastewater. With each Inventory report, EPA strives to improve the data inputs and calculations used.   

Starting on December 8th, 2016, EPA held a series of four stakeholder webinars on the Inventory data and methodology for the waste sector, with a focus on MSW landfills. During the webinar series, EPA presented information on how the Inventory for MSW landfills is developed, proposed various potential methodological changes being considered to improve data quality and transparency within the Inventory involving incorporation of the Greenhouse Gas Reporting Program (GHGRP) data into emissions estimates, and solicited stakeholder feedback on these various improvements.

Please send any input on use of the GHGRP data in the Inventory to

Webinar Summaries and Slides

  • Webinar 1: Background
    December 8, 2016
    In this webinar, EPA provided context on the development of the Solid Waste Inventory, including current methodologies and data sources used to arrive at emissions estimates for the United States. EPA also summarized how the Subpart HH data from the Greenhouse Gas Reporting Program (GHGRP) had been incorporated into the 1990-2014 draft Inventory, but not in the final Inventory estimates. EPA requested input from webinar participants on available data sources and methods that could be most effectively and appropriately used in the Inventory estimates for MSW landfills.
  • Webinar 2: Summary of Stakeholder Input
    January 12, 2017
    In this webinar, the two groups of stakeholders who provided comments from the previous webinar presented their comments and data sources to the larger stakeholder group. Waste Management presented an independent analysis of Subpart HH data, with suggestions on how to use the data in future Inventory years, on behalf of industry stakeholders including Waste Management, Republic Services, SCS Engineers, the National Waste and Recycling Association (NWRA), and the Solid Waste Association of North America (SWANA). Environmental Resource and Education Foundation (EREF) presented two reports that EREF had previously published and offered suggestions on how the Inventory could be improved via their findings. EPA concluded the webinar by offering stakeholders three different proposed options on how the GHGRP subpart HH data could be incorporated into Inventory estimates and asked for feedback on the options.
  • Webinar 3: Update on Methodology Improvements for MSW Landfills (I)
    August 16, 2017
    In this webinar, EPA summarized the major methodological changes made to the 1990-2015 Inventory, including the introduction of a scale-up factor which is applied to the net methane emissions directly reported to subpart HH of the GHGRP to account for emissions from those landfills not required to report to the program. EPA concluded the webinar by noting the immediate Inventory schedule, including the opportunity for stakeholders to provide feedback on the new methodological change during the Inventory expert review and public comment processes, as appropriate.
  • Webinar 4: Update on Methodology Improvements for MSW Landfills (II)
    December 13, 2017
    In this webinar, EPA provided updates on the MSW landfill methodology that resulted from expert review of the dataset used to develop the original scale-up factor value. EPA also provided updates on its review of the oxidation value and degradable organic carbon value used for MSW landfills within the Inventory.

Slides and summary reports for each webinar in the series can be found below.

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