The D.C. Circuit denied environmental groups' petition to review a 2016 rule that EPA uses to determine whether an event caused by recurring activity is "exceptional" and thus exempt from a state's emissions report. The groups argued that EPA misread the definition of "natural event" under the excep...

The Ninth Circuit affirmed a district court's denial of a car owner's motion to intervene in DOJ's case against a German automaker to resolve alleged CAA violations. The owner argued that DOJ's settlement with the automaker violated Virginia's SIP by not requiring all affected vehicles to be bought ...

The D.C. Circuit denied Delaware's petition to review EPA's decision granting the Philadelphia area an extra year to comply with national ground-level ozone standards. Delaware argued that the Agency's extension violated the CAA because not all four states in the Philadelphia area applied for an ext...