EPA/600/R-18/195F| June 2018 | www.epa.gov/research Biofuels and the Environment: Second Triennial Report to Congress EPA/600/R-18/195F June 2018 Biofuels and the Environment Second Triennial Report to Congress U.S. Environmental Protection Agency Office of Research and Development Washington, DC June 29, 2018 1. Table of Contents List of Figures ................................................................................................................................. iv List of Tables .................................................................................................................................. vi Contributors ................................................................................................................................... vii Executive Summary ...................................................................................................................... viii 1 Introduction ............................................................................................................................... 1 1.1 Organization of this Report .................................................................................................. 6 2 Drivers of Environmental Impacts ............................................................................................ 6 2.1 Biofuel Volumes ................................................................................................................... 7 2.1.1 U.S. Biofuel Production .............................................................................................. 7 2.1.2 Biofuel Imports ........................................................................................................... 8 2.1.3 Biofuel Exports ........................................................................................................... 8 2.2 Feedstocks ............................................................................................................................ 9 2.2.1 Acreage ..................................................................................................................... 10 2.2.2 Total Production of Biofuel Feedstocks ................................................................... 11 2.2.3 End Use of Biofuel Feedstocks ................................................................................. 11 2.2.4 Nutrients Applied...................................................................................................... 14 2.2.5 Pesticides Applied .................................................................................................... 16 2.2.6 Conservation Practices.............................................................................................. 18 2.3 Technologies ...................................................................................................................... 19 2.3.1 Biofuel Conversion Technologies ............................................................................ 19 2.4 U.S. Land Use Change ....................................................................................................... 20 2.4.1 Overview .................................................................................................................. 20 2.4.2 Observed Land Use Change to Date ......................................................................... 24 2.4.3 Economic-Based Projections of U.S. Land Use Change Impacts ............................ 43 2.4.4 Conclusions .............................................................................................................. 43 2.5 International Land Use Change .......................................................................................... 45 2.5.1 Observed International Land Use Change ................................................................ 45 2.5.2 Economic-Model Based Estimates of Biofuel-Induced Land Use Change .............. 49 2.5.3 Conclusions .............................................................................................................. 52 3 Environmental and Resource Conservation Impacts ............................................................... 55 3.1 Air Quality .......................................................................................................................... 55 3.1.1 2011 Report Conclusions .......................................................................................... 55 3.1.2 Drivers of Impacts to Air Quality ............................................................................. 56 3.1.3 Impacts to Air Quality .............................................................................................. 58 3.1.4 Potential for Future Changes in Impacts................................................................... 62 3.1.5 Conclusions: Air Quality .......................................................................................... 64 3.1.6 Research Needs: Air Quality .................................................................................... 65 3.2 Water Quality ..................................................................................................................... 65 3.2.1 2011 Report Conclusions .......................................................................................... 66 3.2.2 Drivers of Impacts to Water Quality......................................................................... 67 3.2.3 Impacts to Water Quality .......................................................................................... 68 3.2.4 Potential for Future Changes in Water Quality Impacts ........................................... 73 ii 3.2.5 Conclusions: Water Quality ...................................................................................... 73 3.2.6 Research Needs: Water Quality ................................................................................ 74 3.2.7 Opportunities for Future Environmental Improvements........................................... 74 3.3 Water Quantity ................................................................................................................... 74 3.3.1 2011 Report Conclusions .......................................................................................... 74 3.3.2 Drivers of Impacts to Water Quantity....................................................................... 75 3.3.3 Changes in Relationships between Drivers and Impacts .......................................... 78 3.3.4 Potential for Future Changes in Impacts to Water Quantity ..................................... 81 3.3.5 Conclusions: Water Quantity .................................................................................... 83 3.3.6 Research Needs: Water Quantity .............................................................................. 83 3.3.7 Opportunities for Future Environmental Improvements........................................... 83 3.4 Ecosystem Health and Biodiversity .................................................................................... 84 3.4.1 2011 Report Conclusions .......................................................................................... 84 3.4.2 Drivers of Impacts to Ecosystem Health and Biodiversity ....................................... 85 3.4.3 Impacts to Ecosystem Health and Biodiversity ........................................................ 87 3.4.4 Key Points from Recent Literature ........................................................................... 91 3.4.5 Potential for Future Changes in Impacts to Ecosystem Health and Biodiversity ..... 91 3.4.6 Conclusions: Ecosystem Health and Biodiversity .................................................... 92 3.4.7 Opportunities for Future Environmental Improvements: Ecosystem Health and Biodiversity .............................................................................................................. 92 3.4.8 Research Needs: Ecosystem Health and Biodiversity .............................................. 93 3.5 Soil Quality ......................................................................................................................... 93 3.5.1 2011 Report Conclusions .......................................................................................... 93 3.5.2 Drivers of Impacts to Soil Quality ............................................................................ 94 3.5.3 Changes in Relationships Between Drivers and Impacts ......................................... 96 3.5.4 Potential for Future Changes in Impacts to Soil Quality .......................................... 97 3.5.5 Conclusions: Soil Quality ......................................................................................... 97 3.5.6 Opportunities for Future Environmental Improvements: Soil Quality ..................... 98 3.5.7 Research Needs: Soil Quality ................................................................................... 98 3.6 Invasive Species ................................................................................................................. 98 3.6.1 2011 Report Conclusions .......................................................................................... 98 3.6.2 Drivers of Impacts to Invasive Species..................................................................... 99 3.6.3 Potential Changes in Relationships Between Drivers and Impacts ........................ 100 3.6.4 Potential for Future Changes in Impacts to Invasive Species ................................. 101