Clean Air – Environmental and Energy Law Program

Media Inquiries

Explainer

NAACP v. xAI and the Potential Subversion of Citizen Suits

Can the Trump administration derail environmental citizen suits against favored industries?

November 9, 2026

CleanLaw Podcast

CleanLaw — What’s Happening with US Greenhouse Gas Regulation and Litigation?

Carrie, Sara, and Erika talk recent developments and implications for future climate policy.

November 3, 2026

Regulatory Tracker

EPA VOC and Methane Standards for Oil and Gas Facilities

The Biden EPA finalized three rules regulating methane emissions from the oil and gas sector. One of the rules, the Waste Emission Charge, was repealed using the Congressional Review Act. In Sept. 2025, EPA proposed to delay the GHG reporting rules until 2034. In Nov. 2025, EPA finalized the deadline exemptions for certain provisions regulating methane emissions from new and existing oil and gas sources.

October 29, 2026

Regulatory Tracker

Hydrofluorocarbons and the Kigali Amendment to the Montreal Protocol

In 2022, the U.S. Senate ratified the Kigali Amendment, which committed the U.S. to reducing the use of HFCs. EPA issued multiple rules to implement the mandate. In Oct. 2025, EPA issued a proposed rule to loosen requirements and compliance deadlines for air conditioning, retail food refrigeration, and other sectors.

October 19, 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.

October 6, 2026

Regulatory Tracker

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

The EPA rescinded the Endangerment Finding and all GHG vehicle standards.

October 2, 2026

Regulatory Tracker

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

In September 2026, EPA rescinded most GHG emissions standards from fossil fuel-fired power plants. EPA also proposed a rule that would prevent it from issuing such standards.

October 1, 2026

Regulatory Tracker

Implementation of 2015 Ozone National Ambient Air Quality Standards (NAAQS)

Under the Trump executive order Regulatory Freeze Pending Review, the Biden administration’s final rule setting deadlines for states to submit SIPs for nonattainment areas did not go into effect. EPA announced in June 2025 that it would reconsider the rule and, in June 2026, proposed changes that would eliminate certain SIP requirements for reclassified areas.

September 25, 2026

Regulatory Tracker

National Ambient Air Quality Standards (NAAQS) for Ozone

On March 12, 2025, EPA announced a reconsideration of the NAAQS.

September 25, 2026