Thursday, June 01, 2006

Environmental Costs of Local Ethanol Plant

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The Champaign County Board recently adopted a zoning amendment that clears the way for ethanol production in areas of the county designated for heavy industry. In the amendment the board made a couple of concessions on environmental concerns raised by the Champaign and Urbana city councils, stipulating protections against odor coming from ethanol plants and requiring that they monitor their impact on groundwater supplies.

Even so, I wonder if this isn’t a case where short-term gains are being privileged over long-term interests, where benefits enjoyed by the present generation are obtained by way of risks imposed on generations to follow.

The short-term, local gains represented by an ethanol plant are fairly simple to quantify. It might employ thirty to thirty-five people; it will generate a certain increase in tax revenue; and its presence might raise the price local producers get for a bushel of corn by ten to fifteen cents.

Accounting for the total costs of such a project is more complex, especially if it includes not just money that will be spent by the ethanol producer, but also the environmental impacts borne by the community as a whole.

From a broad perspective, it’s worth remembering that corn-based ethanol isn’t really “renewable” in the way marketers imply that it is. Large quantities of fossil fuel are used to grow corn, including the natural gas used produce nitrogen fertilizer and the fuel used to run farm equipment. Still more fossil fuel is then used to power the ethanol production process. Indeed, whether the system as a whole generates more energy than it consumes is still open to debate. In any case, even under the rosiest scenario only a fraction of the energy available in a given quantity of ethanol can realistically be labeled “renewable.” The rest is, in effect, repackaged fossil fuel.

Locally, the most noticeable negative impacts of ethanol production would be the odor generated by a plant, and the increased traffic associated with it.

The more important concern, however, is the enormous quantity of water that ethanol production uses. The facility proposed near Champaign would pump more than a million and a half gallons a day from the Mahomet Aquifer, one of east central Illinois’ most valuable natural resources. That’s an increase of nearly ten percent over the total currently used by Champaign, Urbana, and nearby communities combined.

Can the aquifer continue to meet other needs in the face of such an increase in demand? The answer to that is probably yes, but the issue is complicated. Scientists are still working out the how quickly the Mahomet Aquifer is recharged, and that rate and the mechanisms for recharge vary from one part of the aquifer to another.

Increased pumping might also entail other risks to the aquifer, including the chance for it to become contaminated with surface water pollutants, and the possibility of mobilizing naturally occurring arsenic within it.

If it should turn out that the Mahomet Aquifer recharges more slowly than we think it does, or our activities wind up degrading the quality of its water, future generations would surely regret that we were using it for dubious industrial purposes.

Thanks to Walt Robinson from the Department of Atmospheric Sciences for Assistance with today’s program.

For more information about the Mahomet Aquifer check out the website for the Mahomet Aquifer Consortium.