Understanding what it takes to move from a corn-based liquid fuels industry to one that is cellulosic-based requires a complex transition over time. This transition implies, among other things, a shift from annual cropping systems considered under United States Department of Agriculture (USDA) policy as commodity crops, to perennial lignocellulosic crops that are herbaceous and wood-based. Because of changes in land use as well as biomass and other crop supplies, land-based environmental amenities such as water quality, soil health and tilth, air quality, and animal and avian species populations and their diversity change also. Environmental effects are measured as magnitudes (how much they are impacted), and direction of the impact (either positive or negative). By developing a series of quantitative and qualitative metrics, the larger issue of defining relative sustainability may be addressed, and this can be done at a finer detail of regional (scale) and environmental amenity-specific impacts. Although much literature exists about research relevant to specific environmental variables, there is no published, documented, nor research literature on direct application of environmental over-compliance with regards a 'biorefinery.' Our three goals were to (1) understand and quantify bioenergy sustainability and some key environmental effects in a generic set of examples
(2) explain the effort and means to define and quantify specific qualitative environmental measures, and to determine a way to understand changes in these measures over time and what their implications might be
and (3) use these outcomes to evaluate potential sites in any geographic area. This would permit assessment of candidate locations, combined with an understanding of co-production of fuels, chemicals, and electric power, to interpret sustainability measures and the relationship between environmental sustainability and economic sustainability. The process of determining environmental sustainability effects as a result of providing renewable energy is complex. We have only included in this report environmental effects as a result of producing biomass for the biorefinery, and the area represented by the footprint of the biorefinery itself. In doing this, we have defined critical environmental variables (water, soil, air, and flora and fauna) and discussed some measurable indicators used to quantify effects such as nitrate content, soil organic matter, air particulates, and avian species diversity, respectively. We also point out the need to perform specific sustainability risk assessments, and the need to continually evaluate the life cycle inventory with an accompanying life-cycle assessment. Only in this dynamic framework can environmental sustainability be determined, evaluated and assessed, and contrasted with economic sustainability goals of a firm or an industry.