The Ninth Circuit upheld EPA's approval of Nevada's SIP for regional haze. In the SIP, Nevada provided reasonable progress goals for attaining natural visibility conditions at the…

The D.C. Circuit held that environmental groups lacked standing to challenge an EPA memo issued to regional directors in response to an earlier court decision vacating the Agency's 2011 Cross…

A district court dismissed an environmental group's CAA citizens suit against EPA for failing to make a finding that Idaho and Utah failed to timely submit SIPs for fine particulate matter (…

The D.C. Circuit vacated EPA's new source review (NSR) rule for Indian country, which established a federal implementation plan (FIP) covering all Indian country nationwide except where EPA…

The D.C. Circuit dismissed Arizona's objection to a consent decree that established a timeline for EPA to approve a SIP, or promulgate a federal implementation plan (FIP), that would meet the…

The Eighth Circuit vacated and remanded EPA's best available retrofit technology (BART) determination for a large power plant in North Dakota, but otherwise upheld EPA's partial…

The D.C. Circuit denied states' and industry groups' petitions challenging EPA rules establishing CAA permitting requirements in states that do not have implementation plans for…

The Tenth Circuit upheld an EPA rule in which it rejected Oklahoma's regional haze plan to limit sulfur dioxide emissions at electric utility power plants and replaced it with its own more…

The Eleventh Circuit vacated EPA's 2011 disapproval of Alabama SIP provisions on opacity, thereby reinstating EPA's 2008 approval of opacity limits. EPA's 2011 disapproval was…

The D.C. Circuit vacated EPA's transport rule, also known as the Cross-State Air Pollution Rule, which sets sulfur dioxide and nitrogen oxides emissions limits for 28 upwind states based on…