Gov. Terry Branstad joined Agriculture Secretary Bill Northey and other state officials in officially protesting the U.S. Environmental Protection Agency’s proposed new rule on the Renewable Fuels Standards, contending that the government should require refiners to blend more grain-based biofuels. Lt. Gov. Kim Reynolds, economic development director Debi Durham and Paul Trombino, director of the Iowa Department of Transportation, also signed the letter. The comment period ended Monday night, after the letter was submitted. “We write once again to strongly encourage you to revise and increase the proposed U.S. Environmental Protection Agency Renewable Fuels Standard volume obligation levels closer to congressionally authorized levels in order to grow the production and use of renewable fuels and revitalize the economy in rural America,” the letter stated. “We have grown increasingly frustrated by the Federal Government’s weakening support for renewable transportation fuels.”