Clean Air – Page 2 – Environmental and Energy Law Program

Quick Takes

A Legal Challenge with Major Implications for Citizen Suits

DOJ intervenes in and moves for dismissal of citizen suit, citing primacy of its own enforcement discretion

June 16, 2026

Regulatory Tracker

Power Plant Startup, Shutdown, and Malfunction Rule

In June 2026, EPA partially withdrew SSM SIP Call findings of failure to submit, leaving four state agencies with outstanding SSM revision obligations.

June 12, 2026

Legal Analysis

EPA Proposes to Limit Its Responsibility to Revise Hazardous Air Pollution Standards

Analysis of the proposal regarding previously unregulated hazardous air pollutant emission points, the agency’s legal rationale, and the implications for EPA’s broader obligations under the Clean Air Act.

June 9, 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.

June 9, 2026

Regulatory Tracker

National Ambient Air Quality Standards (NAAQS) for Ozone

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

June 9, 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 One of the rules, the Waste Emission Charge, was repealed using the Congressional Review Act.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.

June 8, 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.

May 26, 2026

Regulatory Tracker

Air Transport Rules: Cross-State Air Pollution Rule/Good Neighbor Plan Rule

The Clean Air Act’s Good Neighbor provision requires upwind states to ensure that their instate sources do not contribute to downwind states’ attainment of the NAAQS. On Mar. 12, 2025, EPA announced its plan to roll back the Biden administration’s Good Neighbor Plan, which the Supreme Court stayed in June 2024.

April 27, 2026

Quick Takes

EPA’s Proposal to Rescind Ethylene Oxide Emissions Standards for Commercial Sterilizers

A look at EPA’s four main rescissions and the agency’s rationale.

April 21, 2026