United Press International: More than a year ago, Congress passed a law requiring massive increases in the production of ethanol and other biofuels, but with the economy tanking, concerns about the mandate are popping up in every corner. The Renewable Fuel Standard, passed as part of the Energy Independence and Security Act of 2007, requires the nation to produce 36 billion gallons of biofuels by 2022. Although increasing biofuels production at home could decrease U.S. dependence on foreign oil, the law has been …