U.S. Agriculture Secretary Tom Vilsack said he is pushing the Environmental Protection Agency to raise the amount of ethanol allowed in gasoline as the deadline for a decision nears.

Science indicates that a higher “blend wall” is safe for automobile engines, Vilsack said recently in an interview at a conference on global hunger in Des Moines, Iowa. Increasing production of ethanol, made from corn in the U.S., would also meet national goals of energy independence and aid the industry as it attempts to expand. “We will continue to publicly advocate an increase, and privately advocate,” Vilsack said. “Our hope is they understand the significance of this decision as it relates to the future of the industry.”

The U.S. biofuels industry is challenged by infrastructure limitations and a government-imposed limit, called a blend wall, that restricts to 10.2 percent the amount of ethanol that can be mixed with gasoline, the Government Accountability Office said in a recent report. This past spring, a group representing ethanol producers filed an emergency request asking EPA to waive its standard data-gathering process for transportation fuel changes and make E15—a 50% increase from E10 blends—a standard transportation fuel. The emergency waiver request requires EPA to deliver a decision by December 1. The request has encountered resistance from a growing number of interests, including small engine and marine manufacturers and more recently major auto manufacturers that claim greater biofuels content may hurt engine performance and increase corrosion and that more research is needed.