D.C. Circuit Vacates EPAs Cross-State Air Pollution Rule
By KEVIN POLONCARZ & MICHAEL BALSTER
On August 21st, the United States Court of Appeals for the District of Columbia Circuit (Court), in a 2-1 split decision, vacated the U.S. Environmental Protection Agencys (EPA) Cross-State Air Pollution Rule (CSAPR or the Transport Rule), which regulates emissions from upwind states that contribute to air quality problems in downwind states. The Court found that EPA's approach for evaluating which states significantly contribute to downwind nonattainment ran afoul of the Clean Air Act's "good neighbor provision" and that EPA's simultaneous promulgation of that approach along with federal implementation plans requiring reductions from upwind states violated the Clean Air Act's principles of cooperative federalism. The Court ordered EPA to continue implementing a predecessor rule, known as the Clean Air Interstate Rule, which itself was remanded by the Court in 2008, while EPA develops a replacement to both rules. How EPA proceeds in the wake of this decision and the prior decision striking down its earlier effort to use a market-based trading program to combat interstate pollution is highly uncertain.