On January 19, 2021, the last full day of President Trump’s tenure at the White House, the D.C. Circuit Court of Appeals essentially said “good riddance” to Trump’s “ACE” (the Affordable Clean Energy Rule)  in American Lung Association v. EPA, No. 19-1140 (D.C. Cir. 2021). More to the point, the D.C. Circuit held that the Trump EPA’s interpretation that emission controls under section 111 of the Clean Air Act must be limited to those that can be applied “at” and “to” a stationary source when determining the Best System of Emission Reduction (BESR) was inconsistent with the Clean Air Act itself. 

As a result of the D.C. Circuit Opinion, the Clean Power Plan (CPP) of the Obama Administration, which contained the first-ever national limits on climate pollution from existing coal and natural gas-fired power plants was resurrected and the Biden administration was presented with somewhat of a clean slate to chart its own course. For a moment in time, however, that may have ended this past Friday, October 29, 2021, when the U.S. Supreme Court granted certiorari to hear challenges to EPA’s authority to regulate Greenhouse Gas (GHG) Emissions from power plants. CERT

In what is likely to be the most significant Clean Air Act decision of the Court since Massachusetts v. EPA, 549 U.S. 497 (2007), wherein the Court ruled that climate pollution qualified as air pollution that is subject to regulation under the Clean Air Act, the Court granted requests from coal companies and others to review the D.C. Circuit January 2021 decision which struck down the Trump Administration’s ACE rule and its repeal of the Obama CPP.

Arguments are anticipated in early 2022 with a decision of potential monumental impact likely before the Court departs for its summer 2022 recess.