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Emission Factor Documentationfor AP42 Section 2.4 Municipal Solid

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Emission Factor Documentationfor AP42 Section 2.4 Municipal Solid Background Information Document for Updating AP42 Section 2.4 for Estimating Emissions from Municipal Solid Waste Landfills EPA/600/R-08-116 September 2008 Background Information Document for Updating AP42 Section 2.4 for Estimating Emissions from Municipal Solid Waste Landfills Prepared by Eastern Research Group, Inc. 1600 Perimeter Park Dr. Morrisville, NC 27560 Contract Number: EP-C-07-015 Work Assignment Number: 0-4 EPA Project Officer Susan Thorneloe Air Pollution Prevention and Control Division National Risk Management Research Laboratory Research Triangle Park, NC 27711 Office of Research and Development U.S. Environmental Protection Agency Washington, DC 20460 Notice The U.S. Environmental Protection Agency (EPA) through its Office of Research and Development performed and managed the research described in this report. It has been subjected to the Agency‘s peer and administrative review and has been approved for publication as an EPA document. Any opinions expressed in this report are those of the author and do not, necessarily, reflect the official positions and policies of the EPA. Any mention of products or trade names does not constitute recommendation for use by the EPA. ii Abstract This document was prepared for U.S. EPA’s Office of Research and Development in support of EPA’s Office of Air Quality Planning and Standards (OAQPS). The objective is to summarize available data used to update emissions factors for quantifying landfill gas emissions and combustion by-products using more up-to-date and representative data for U.S. municipal landfills. This document provides background information used in developing a draft of the AP-42 section 2.4 which provides guidance for developing estimates of landfill gas emissions for national, regional, and state emission inventories. EPA OAQPS will be conducting the review of Section 2.4. Once comments are addressed, the AP-42 section will be updated and available through EPA’s Technology Transfer Network (TTN) Clearinghouse for Inventories & Emissions (http://www.epa.gov/ttn/chief/ap42/). This report is considered a stand-alone report providing details of available data and analysis for developing landfill gas emission factors and combustion by-products for a wider range of pollutants and technologies. The inputs that are described in this report are used in EPA’s Landfill Gas Emission Model (LandGEM) for developing inputs for state, regional, and national emission inventories. Data from 62 LFG emissions tests from landfills with waste in place on or after 1992 were used to develop updated factors for use in LandGEM. This document also provides updated and additional emission factors for combustion by- products for control devices such as flares, boilers, and engines. Of the 293 emissions tests submitted to EPA for this update, over 200 contained inadequate documentation or information for use in this update. The reports that were used included LFG composition data and, in some cases, emissions data on LFG combustion by-products. These emissions tests were screened for quality and compiled to create emission factors for non-methane organic compounds (NMOC), as well as speciated compounds in LFG. This update expands the list of emission factors for LFG constituents from 44 to 167 and provides many more “A” quality rated emission factors. Likewise, combustion by-product emission factors for dioxins/furans were added in this update, along with improved ratings of the other combustion by-product emission factors as a result of the addition of new data. Updated information is provided of changes in the design and operation of U.S. MSW landfills along with updated statistics on the amount of waste being landfilled. Guidance for measuring uncontrolled emissions is provided for quantifying area source emissions (OTM 10). EPA’s recommended approach is based on the use of Optical Remote Sensing technology and Radial Plume Mapping (ORS-RPM) to characterize emissions from any leaks in the header pipes, extraction wells, side slopes, or cover material. The first-order equation used to estimate LFG emissions has been modified to add a factor to account for LFG capture efficiency. Due to the increase in the use of leachate recirculation, a gas production rate to characterize emissions from wet landfills has been added. Information on the air emission concerns regarding construction/demolition waste landfills and landfill fires have also been added to the AP-42 section. iii Foreword The U.S. Environmental Protection Agency (EPA) is charged by Congress with protecting the Nation’s land, air, and water resources. Under a mandate of national environmental laws, the Agency strives to formulate and implement actions leading to a compatible balance between human activities and the ability of natural systems to support and nurture life. To meet this mandate, EPA’s research program is providing data and technical support for solving environmental problems today and building a science knowledge base necessary to manage our ecological resources wisely, understand how pollutants affect our health, and prevent or reduce environmental risks in the future. The National Risk Management Research Laboratory (NRMRL) is the Agency’s center for investigation of technological and management approaches for preventing and reducing risks from pollution that threaten human health and the environment. The focus of the Laboratory’s research program is on methods and their cost-effectiveness for prevention and control of pollution to air, land, water, and subsurface resources; protection of water quality in public water systems; remediation of contaminated sites, sediments and ground water; prevention and control of indoor air pollution; and restoration of ecosystems. NRMRL collaborates with both public and private sector partners to foster technologies that reduce the cost of compliance and to anticipate emerging problems. NRMRL’s research provides solutions to environmental problems by: developing and promoting technologies that protect and improve the environment; advancing scientific and engineering information to support regulatory and policy decisions; and providing the technical support and information transfer to ensure implementation of environmental regulations and strategies at the national, state, and community levels. This publication has been produced as part of the Laboratory’s strategic long-term research plan. It is published and made available by EPA’s Office of Research and Development to assist the user community and to link researchers with their clients. Sally C. Gutierrez, Director National Risk Management Research Laboratory iv Acknowledgements We would like to thank those providing data and information used to help develop more up-to-date and credible emission factors for evaluating air emissions from landfills and combustion by-products from the control of landfill gas emissions. We would also like to thank those helping to review this report including Jim Topsale of EPA Region III; Tom Driscoll, K.C. Hustvedt, Ron Myers, and Hillary Ward of EPA’s Office of Air Quality Planning and Standards; Rachel Goldstein of EPA’s Landfill Methane Outreach Program (LMOP); and Bob Wright and Andy Miller of EPA’s Office of Research and Development (ORD). We would also like to thank the Environmental Research and Education Foundation (EREF). Through a Cooperative Research and Development Agreement (#200-C-09) between EPA ORD and EREF , co-funding was provided which helped to complete data collection and analysis. Co-funding was also received from EPA’s LMOP program to help complete the data analysis to update combustion by-products from technologies utilizing methane (i.e., internal combustion engines, boilers, and turbines). v TABLE OF CONTENTS Page Notice.................................…………….......................................................................................ii Abstract........................................................................................................................................iii Foreward ..................................................................................................................................... iv Acknowledgements .................................................................................................................... v Appendicies ...............................................................................................................................vii List of Tables ............................................................................................................................viii 1.0 INTRODUCTION .........................................................................................................................1 2.0 UNCONTROLLED LANDFILL GAS DATA ANALYSIS RESULTS....................................4 2.1 Estimation of Uncontrolled Landfill Gas Emissions...……………………………………4 2.2 Data Summary ..................................................................................................................10 2.3 NMOC and VOC ..............................................................................................................14 2.4 Speciated Organics and Reduced Sulfur Compounds....................................................... 17 2.5 Methane, Carbon Dioxide, Carbon Monoxide, Oxygen and Nitrogen .............................18 2.6 Hydrogen Chloride...........................................................................................................18 2.7 Landfill Gas Constituent
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