The D.C. Circuit held that EPA unlawfully revoked the 1997 ozone NAAQS when it implemented the 2008 standard. In 2008, EPA set the ozone NAAQS at 75 parts per billion (ppb). In 2015, when implementing the standard, the Agency eliminated the 1997 standard of 84 ppb on the grounds that it was impossib...

A district court held that EPA failed to act when it did not rule within 60 days on Connecticut's petition concerning upwind pollution. In June 2016, Connecticut filed a petition pursuant to §126(b) of the CAA for EPA to make a finding that Brunner Island is emitting air pollutants that significant...

The D.C. Circuit held that EPA did not violate the CAA by modifying, without notice and comment, its prior understandings of how to measure a proposed transportation project’s impact on ambient levels of particulate matter. In 2006, EPA revised “hot spot" regulations for fine particulate matter....