2008-01-24_AgendaPacket - Laserfiche WebLink

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Fresh Wa[er & 4 COZ Recycled Water Sources Steam Enzymes ~. -' ~ ~ Mash Cooling Whole Corn Jet Cooker Hammer Slurry Tank Liquefaction - Up to 5% Mtll Yeast > _ Gasoline '~~ Y - _ -~ ~ Fermentation A~-:fM {t u1~~ ii U ~ tux [ r ,` 2l1° Proof cular SI ' I`. E¢hnnuP ~' Ethanol ~~', F h'~I ' 1 Beer a duce' I 1 1 - - 190 Proof i I-. ODGS Finai Ethanol ~ ~ e ` Product _. - ~ I - r - i ~ -___ _.- ~ ~ C Ili ~ i -. t wet Grain Syrup Evaporator ~'.","~ I Whole i ~Stlllage F ~ -~ ~~ ~~` - Centrifuge _ I __.. Condensate -"' ~f ,Ir k`:,! ;~ ( '.~..,. Thin ~~ ~ Stillage souRCe: PARKIN etal (2.007) continued from page 1 The volume of water use and level of water quality are primary concerns, locally and nationally. Raising awareness among the public regarding potential negative impacts from the increase in corn production for ethanol and other biofuels must take top priority within the already crowded arena of water management challenges. From the dangerously low aquifers of Atlanta to the decreasing level of the Colorado River, the rising need for groundwater and surface water for crop irrigation and ethanol production will face major competition. Water Use Impacts -Irrigation and Ethanol Production Crops used for biofuels require adequate moisture from rainfall or irrigation. Regardless of the source, most water leaves crop fields through evaporation, transpiration from plants, runoff to rivers and streams, and infiltration into the aquifer. If rainfall is adequate, this natural loss of moisture is of less concern; however, as the need for irrigation and the competition for groundwater increases, the level of concern increases, as well. USDA research in Nebraska estimated that 2,100 gallons of irrigated water are required to produce 1 bushel of corn. With 2.7 gallons of ethanol produced per bushel, an irrigated field would use the equivalent of 780 gallons of water per gallon of ethanol produced. Added to this impact is the amount of water required at the ethanol production facility, itself, typically located within a 50 mile radius of the feedstock production area. Requiring a water use permit from the DNR, an ethanol plant that produces 100 million gallons of ethanol per year uses approximately 400 million gallons of water per year, or around 1 million gallons per day (similar to the public water needs of a town with a population of `'~'^ FACETS December 2007 Water Quality Impacts 5,000). The amount of water used in irrigation (780 gallons per 1 gallon of ethanol), plus the amount used for production (4 gallons of water per gallon of ethanol) totals a startling 784 gallons of water to produce 1 gallon of ethanol. While the water needs of ethanol production facilities are similar to those of other industries, the addition of the draw down over time may present a major groundwater problem to a region where the aquifer recharge cannot keep up with the withdrawal. Placement of these facilities requires careful consideration of the total watershed resources. Water quality concerns relate primarily to use of nitrogen as a fertilizer, use of pesticides, soil erosion from runoff of feedstock (corn or other crops), agricultural practices, and use of what was considered marginal land. As a feedstock, corn requires one of the highest application rates for both fertilizers and pesticides. Increased use of nitrogen to produce higher yields can result in excess nutrients in lakes, streams and rivers, impairing fish and wildlife habitat as well as human health concerns in ground water. Indeed, excess nitrogen has been found to be the major cause of the oxygen-starved "dead zone" in the Gulf of Mexico and other bodies of water. Pesticides may also leach into groundwater - a 2006 study detected pesticides in 61°/o of shallow wells in agricultural areas, but only 1% were at levels greater than those thought to impact human health. However, while groundwater may be more difficult to contaminate, it is also the most difficult and expensive to reclaim. Soil erosion is another concern of increased agricultural production for biofuels. Soil erosion produces sediment, which is currently responsible for 50% of the recently classified "impaired waters". Withdrawal of land from the USDA's Conservation Reserve Program (CRP) has raised concerns regarding soil erosion. CRP makes annual payments to landowners who commit to converting environmentally sensitive or marginal lands to non- agricultural uses for a period of 10 to 15 years. As of October 1, 2007, the states of Minnesota, North Dakota, South Dakota and Iowa have lost over 750,000 CRP acres and could lose another 1.1 million by 2.010. Agricultural best practices of no-tillage or partial-tillage go a long way in reducing erosion, environmental concerns related to wildlife habitat, and contaminants through filtration and runoff. continued on next page