Valero Energy Corp. v. Environmental Protection Agency

Issue: (1) Whether the requirement that the Environmental Protection Agency "shall" make a "calendar year" determination of the "appropriate" point of obligation requires the EPA to consider in each annual rule whether the point of renewable fuel obligation applicable to refineries, blenders, and importers remains appropriate; and (2) whether the EPA can evade the annual duty by partitioning the point of obligation into a one-time collateral proceeding that ignores key evidence, relies primarily on the agency"s own convenience and claims more deference from a reviewing court than an annual rule would receive.