ELR Citation: 52 ELR 20042
No(s). 9:19-cv-00012- DWM (9th Cir. Apr 4, 2022)

The Ninth Circuit, 2-1, affirmed in part and reversed in part summary judgment for DOI in a challenge to its approval of a mine expansion proposal in Montana. Environmental groups argued DOI violated NEPA by failing to take a "hard look" at the actual environmental effects of the expansion's greenhouse gas (GHG) emissions—namely, by failing to use the social cost of carbon metric to quantify the harms—and by failing to provide convincing reasons for its finding that the expansion would not have a significant impact on the environment. A district court concluded that DOI adequately explained its decision not to use the social cost of carbon metric, and granted summary judgment for the Department on all but the groups' claim that it failed to consider the risk of coal train derailments. The appellate court agreed that the Department was not required to use the social cost of carbon metric to quantify environmental harms stemming from the expansion's GHG emissions, but found that DOI failed to provide convincing reasons to support its FONSI, in violation of NEPA. It affirmed in part, reversed in part, and remanded to the district court for further proceedings.