Air Quality & Climate Change

Arnold & Porter's Air Quality and Climate Change practices span regulatory and compliance counseling, participation in rulemaking activities, representation in government and citizen enforcement actions, and litigation of disputes. Our team includes a former EPA lawyer with 25 years of Clean Air Act experience beginning with implementation of the Clean Air Act Amendments of 1990, and the Andrew Sabin Professor of Professional Practice and Director of the Sabin Center for Climate Change Law at Columbia Law School.

We represent clients in the automotive, engine, railroad, fuel, electric power, stored energy and chemical industries across all aspects of the federal Clean Air Act, as well as various state programs, particularly California. We appear regularly before US EPA, the various EPA Regional Offices, and the California Air Resources Board.

We have one of the leading "mobile source" practices in regulatory, compliance, and enforcement matters under Title II of the Clean Air Act and parallel California requirements. Our experience includes:

  • vehicle and engine certification issues;
  • defect reporting and recalls;
  • importation;
  • alternative fuel and technology issues;
  • labeling and exemption issues;
  • enforcement;
  • participation in rulemaking and litigation challenging agency decisions; and
  • litigation regarding state tort claims.

We also have an extensive and leading practice regarding the full range of Clean Air Act issues facing "stationary sources." We assist such clients in addressing:

  • permitting issues (including PSD, New Source Review and NSPS applicability and compliance);
  • hazardous air pollutant (MACT) compliance and enforcement;
  • Title V permitting;
  • Regional Haze and BART rulemakings and disputes;
  • National Ambient Air Quality Standards rulemaking and compliance;
  • EPA's Greenhouse Gas Reporting rules compliance; and
  • participation in rulemaking and litigation challenging agency decisions.

Our broader climate change practice also extends to renewable energy standards, carbon trading, "green washing," green real estate, and fuel efficiency laws and regulations. We have represented clients on some of the most significant litigation matters relating to climate change. Our experienced team is called upon for assistance with issues involved in land use and development, power and transportation policy, corporate governance, international trade, and corporate transactions.

We maintain a comprehensive chart that displays US climate change litigation, covering pending as well as decided cases. Those interested in receiving updates to this chart should send a note to Margaret Barry. We offer a link to the President's Climate Action Plan Tracker, prepared by Columbia Law School, which is directed by senior counsel Michael Gerrard. These have links to federal legislation and relevant documents plus a database of required rulemakings and other federal agency actions.


Alliance of Automobile Manufacturers Rulemaking and related litigation

Advise on rulemaking and related litigation.

Major motorcycle, ATV and marine engine manufacturer Enforcement actions

Advise on enforcement matters.

Leading fertilizer producer Defense of US EPA claims

Defending against US EPA claims for NSR/PSD violations and claims for violations of hazardous air pollutant requirements

Global industrial engine manufacturer and construction equipment manufacturer Enforcement and regulatory actions

Advise on enforcement and regulatory matters.

Fortune 500 energy company Compliance and enforcement actions

Represent client in compliance and enforcement matters concerning gasoline regulations, alternative fuels, and regulatory compliance.



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