The Ninth Circuit denied an environmental group's petition challenging EPA's approval of a revision to California's SIP. The revision provided alternative "not less stringent" controls to what is required in CAA §185's antibacksliding measures, which require that major stationary sources of polluti...

The Ninth Circuit upheld the dismissal of a trucking association's federal preemption challenge to a California environmental regulation on diesel trucks. The regulation requires heavy-duty diesel trucks, whose emissions contribute significantly to particulate matter and ozone pollution, to be upgra...

A district court dismissed EPA's lawsuit against an Oklahoma utility under the CAA alleging that it failed to properly project whether modifications made to two coal-fired power plants would result in an increase in emissions. The plants were constructed before Congress enacted the PSD program. As a...