We previously reported on industry challenges to U.S. EPA's grant of a partial waiver under the Clean Air Act allowing the use of gasoline containing up to 15 percent ethanol by volume ("E15") in model year 2007 and newer light-duty vehicles (i.e., cars, light-duty trucks, and medium-duty passenger vehicles). Additional challenges were filed recently in the U.S. Court of Appeals for the D.C. Circuit after EPA extended the waiver to allow the use of E15 in model year 2001 to 2006 light-duty vehicles. "Partial Grant of Clean Air Act Waiver Application Submitted by Growth Energy to Increase the Allowable Ethanol Content of Gasoline to 15 Percent; Decision of Administrator," 76 Fed. Reg. 4662 (Jan. 26, 2011).

The first petition for review was filed February 16, 2011, Alliance of Auto. Mfrs. v. U.S. Envtl. Prot. Agency, No. 11-1046 (D.C. Cir.); another was filed March 11, 2011, Grocery Mfrs. Ass'n v. U.S. Envtl. Prot. Agency, No. 11-1072 (D.C. Cir.); and a third was filed on March 21, 2011, Nat'l Petrochemical & Refiners Ass'n v. U.S. Envtl. Prot. Agency, No. 11-1086 (D.C. Cir.). On its own motion, the Court of Appeals consolidated the three new cases with the three existing cases challenging the partial waiver for model year 2007 and newer vehicles.