The U.S. Environmental Protection Agency is holding its only hearing Thursday in Kansas City, Missouri, on its announcement last month to boost output of biofuels next year, as well as biomass-based diesel levels for 2018.

The EPA’s final rule is expected by the end of the year.

Next year’s target of 18.8 billion gallons of renewable fuels, mostly ethanol, is less than the 24-billion-gallon threshold set in a 2007 renewable fuels law.

Ethanol advocates largely in farming states want the target raised. Oil companies counter that the market, not the government, should determine how much ethanol is blended into gas.