FILE - In this July 20, 2013, file photo, an ethanol plant stands next to a cornfield near Nevada, Iowa. The Obama administration has failed to study as legally required the impact of requiring ethanol in gasoline and ensuring that new regulations intended to address one problem do not actually make other problems worse, the Environmental Protection Agency inspector general said Thursday, Aug. 18, 2016. The conclusion in the new audit confirmed findings of an Associated Press investigation in November 2013. (AP Photo/Charlie Riedel, File) The Associated Press