The Ninth Circuit granted in part and denied in part a petition to review EPA's final rule approving California's SIP for meeting the air quality standard for ozone in the San Joaquin Valley. An environmental group argued the SIP's contingency measure was inadequate because it provided only a nomina...

The D.C. Circuit denied a challenge to EPA's 2015 rule updating the standards under which the Agency audits wood-burning heaters' compliance with CAA emissions limits. An industry group argued the rule was invalid because, unlike the 1988 rule, it authorized testing at other labs and neither account...

The Eighth Circuit affirmed in part and reversed in part a district court ruling in an ongoing enforcement suit concerning air pollution at a utility company's coal-fired power plant in Missouri. EPA argued the company violated the CAA, Missouri's SIP, and its Title V permit by performing modificati...

A Minnesota appellate court remanded a challenge to the Minnesota Pollution Control Agency's (MPCA's) grant of an air emissions permit for a proposed copper-nickel mine in northern Minnesota. Environmental groups argued the MPCA improperly issued the permit because the company receiving it did not i...

The D.C. Circuit granted in part environmental groups' petition to review EPA's 2019 rule setting annual renewable fuel volume levels under the Renewable Fuel Standard (RFS) program. The groups argued that EPA's "aggregate compliance approach" for determining whether biofuel qualifies as renewable f...