The D.C. Circuit granted in part and denied in part petitions concerning EPA's NESHAPs for industrial boilers. The first challenge raised by environmental groups concerned regulations that indirectly control a group of organic pollutants by limiting carbon monoxide emissions as a proxy for the targe...

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....

A district court ordered EPA to issue infrastructure requirements for the 2012 fine particulate matter NAAQS for five states within 90 days. In 2015, New Jersey, Pennsylvania, Washington, Illinois, Massachusetts, and Rhode Island missed their deadlines to present compliance plans for the 2012 fine p...

A district court denied EPA's request to amend a 2012 consent decree obligating the Agency to approve state regional haze plans. In 2011, environmental groups sued the Agency to compel it to take action on nine states' regional haze plans. Under a consent decree, EPA was given until September 9, 201...

The Ninth Circuit upheld a 2014 EPA settlement that required the Agency to set a phased schedule for it to issue air quality designations as required by a 2010 sulfur dioxide NAAQS. In 2013, when EPA missed the statutory deadline to issue its designations under the CAA, environmental groups sued to ...

The Tenth Circuit rejected EPA's decision to deny an oil company's request for an exemption from the blending requirement under the Renewable Fuel Standards Program of the CAA. In 2005, Congress amended the CAA to require refiners and importers to blend biofuels into gasoline to cut down on greenhou...

The D.C. Circuit held that EPA overstepped its authority under the CAA when it banned the use of hydrofluorocarbons (HFCs) in products. In 2015, EPA issued a rule that restricted the manufacture of products containing HFCs. EPA based this decision on its authority to regulate "ozone depleting substa...

The D.C. Circuit held that EPA must justify emissions limits set for certain hazardous air pollutants. The CAA requires EPA to set limits for seven different hazardous air pollutants (HAPs). In 2015, the Agency claimed to have identified sources of these pollutants and set emissions limits for them....