350 Montana v. Haaland

In a split opinion, the Ninth Circuit Court of Appeals ruled that federal defendants violated the National Environmental Policy Act (NEPA) by failing to provide a “convincing statement of reasons” why the impacts of a coal mine’s expansion on greenhouse gas emissions would be insignificant. The court found that the environmental assessment (EA) did not articulate “science-based criteria” for significance and relied on an arbitrary and capricious determination that the project’s emissions would be “relatively ‘minor,’” even though the EA calculated that greenhouse gas (GHG) emissions over the life of the project would total 0.44% of annual global emissions and the mine was projected to generate more greenhouse gases annually than the largest single point source in the U.S. The Ninth Circuit stated: “The lack of a science-based standard for significance is critical because the record before us reflects no dispute that GHGs cause global warming and have had dramatic effects on the environment. The only question is the extent to which this particular project’s GHGs will add to the severe impacts of climate change.” The court separately found that the EA’s comparisons of the project’s emissions with total U.S. emissions and total Montana emissions did not comply with NEPA because the federal defendants did not account for coal combustion emissions overseas, “obscuring and grossly understating the magnitude of … emissions relative to other domestic sources.” The Ninth Circuit concluded, however, that the defendants were not required to use the Social Cost of Carbon metric to quantify the environmental harms of the project’s greenhouse gas emissions. But the court said NEPA and the Administrative Procedure Act required that the defendants use some methodology beyond the “bare comparisons” employed in the EA. The dissenting judge concluded that the finding that the project’s incremental effects were minor was not arbitrary and capricious under the APA’s deferential review standard.