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FIGURE 4-1 A framework for EPA sustainability decisions (level 2).

BOX 4-1
Biofuels

Adopting a sustainability framework could help address the social, economic and environmental impacts of biofuel expansion and guide policy decisions toward more sustainable energy supplies. Concerns over energy security, environmental impacts, cost, and availability led to the passage of the Energy Independence and Security Act of 2007 establishing an ambitious goal of producing 36 billion gallons of biofuels annually by 2022. Biofuels are a renewable energy source that can be produced domestically with potentially reduced environmental impacts compared with fossil-fuels. However, the push for biofuels preceded careful sustainability analysis, and the rapid expansion of biofuels production raised its own set of social, economic, and environmental concerns.

The law also requires EPA to report to Congress every three years on the impact of biofuel production on the air, water, and soil quality; ecosystem health and biodiversity, and invasive and noxious plants. The reports are required to include a quantitative assessment of significant environmental changes associated with biofuels production. To date, EPA has not been able to complete a quantitative risk assessment of biofuel production because of a number of factors, including the significant data limitations, substantial uncertainties associated with the production and conversion of biomass feedstocks to biofuels, and a lack of consistency in biofuel production by region.

Impact on food prices: In 2010, 38% of the U.S. corn harvest went to ethanol production. In 2010, total U.S. ethanol production was 13.23 billion gallons (RFA 2011) while U.S. corn production was 12.45 billion bushels (USDA 2011). To produce 13.23 billion gallons, assuming 2.8 gallons of ethanol per bushel of corn, requires 4.725 billion bushels, or 37.95% of total corn production. Some



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