The Supreme Court has granted EPA’s petition for certiorari to the DC Circuit decision vacating CSAPR. The Court will be reviewing the following questions:
(1) Whether the court of appeals lacked jurisdiction to consider the challenges to the Clean Air Act on which it granted relief;
(2) whether states are excused from adopting state implementation plans prohibiting emissions that “contribute significantly” to air pollution problems in other states until after the EPA has adopted a rule quantifying each state’s inter-state pollution obligations; and
(3) whether the EPA permissibly interpreted the statutory term “contribute significantly” so as to define each upwind state’s “significant” interstate air pollution contributions in light of the cost-effective emission reductions it can make to improve air quality in polluted downwind areas, or whether the Act instead unambiguously requires the EPA to consider only each upwind state’s physically proportionate responsibility for each downwind air quality problem.