Corridor Business Journal: The U.S. Environmental Protection Agency on Tuesday proposed increasing the volume of biofuels blended into the nation’s fuel supply by 3 percent in 2019, to 19.88 billion gallons, but it was the proposal’s position on “conventional” biofuels that caught the attention of farm state officials. The EPA’s proposal calls for maintaining “conventional” renewable fuel volumes, such as corn-based ethanol, at the congressionally mandated level of 15 billion gallons, while increasing volumes of advanced biofuels and cellulosic biofuels by a combined 700 million gallons. The EPA also decided against a plan forcing large refiners to blend extra volumes to compensate for the hardship waiver exemptions granted to small refineries — a decision that did not sit well with Iowa’s ag and political leaders.