With the high correlation between oil and ethanol prices, if oil prices drop, ethanol is at risk of losing its market.
The U.S. market is protected from Brazilian ethanol. If the $.54 per gallon tariff is not renewed in October, ADM could suffer. This is provided, of course, that ADM does not itself expand more into Brazilian ethanol.
ADM has invested great amounts of money into South America and China. This brings increased economic and political risks.