Clean Air – Environmental and Energy Law Program

Regulatory Tracker

Clean Car Rules — Corporate Average Fuel Economy Standards/Greenhouse Gas Standards

The EPA rescinded the Endangerment Finding and all GHG vehicle standards.

September 2, 2026

Regulatory Tracker

Regulating Greenhouse Gases for New and Existing Fossil Fuel-Fired Power Plants

In June 2025 EPA proposed a rule rolling back the 2024 EPA standards for GHG emissions from existing coal-fired power plants and new gas-fired power plants.

August 26, 2026

Regulatory Tracker

Regional Haze Rule

Through two state plan approvals, EPA finalized a new policy that eases all states’ Regional Haze planning obligations. Environmental groups are challenging the approvals.

August 21, 2026

CleanLaw Podcast

CleanLaw — DOJ’s Environment and Natural Resources Division, Past and Present

Erika, Andy, and Sommer talk about their time at ENRD and how recent changes are reshaping the work of “the government’s lawyers.”

August 20, 2026

Regulatory Tracker

Once In Always In Guidance for Major Sources under the Clean Air Act

Congress used the Congressional Review Act to repeal the 2024 rule and reinstated the 2020 rule, which allows a major source to reclassify as an area source if the source reduces HAP emissions.

August 18, 2026

Regulatory Tracker

Mercury and Air Toxics Standards

EPA rescinded the 2024 mercury and air toxics standards (MATS) for power plants and reinstated the 2012 MATS.

August 13, 2026

Regulatory Tracker

New Source Review

EPA establishes the baseline requirements for new source review (NSR) permits, which are then issued by state and local air pollution agencies. In 2025 and 2026, EPA made changes to the NSR program easing permitting requirements.

August 6, 2026

Regulatory Tracker

National Ambient Air Quality Standards (NAAQS) for Particulate Matter (PM)

The CAA requires EPA to review and set primary and secondary standards for PM NAAQS every 5 years. The Biden EPA strengthened the standard in March 2024.

July 17, 2026

Quick Takes

D.C. Circuit Upholds EPA’s 2024 Fine Particulate Matter Standard

Analyzis of the legal challenges to the standard and how the D.C. Circuit’s rejection of those challenges may affect future air quality rulemakings.

July 8, 2026