Reuters: U.S. agricultural processor Archer Daniels Midland Co said on Wednesday it was “cautiously optimistic” about the struggling ethanol industry because U.S. law still mandates its use. The ethanol industry had been worried that the U.S. Environmental Protection Agency would scale back requirements for ethanol use in a new draft Renewable Fuels Standard this month, but it left its annual blend targets intact. “We do know that the RFS fuel standard will increase to 12 billion …