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BakerHostetler has one of the premier Clean Air Act (CAA) law practices in the country. Our team of environmental and appellate attorneys has worked on many of the most consequential CAA cases in history.

We prepare comments on significant CAA rulemakings and challenge them successfully in federal court. BakerHostetler also has worked on the largest civil and criminal environmental enforcement cases in the country. We routinely advise clients on complex regulatory compliance and permitting matters under the CAA, including New Source Review (NSR) and Title V permitting, renewable fuel standards, vehicle emission standards and hazardous air pollutant regulations. We have successfully defended CAA permits issued to our clients in state and federal administrative and judicial proceedings when those permits are collaterally attacked through citizen suits and Title V-related petitions. These defenses have led to precedent-setting decisions favorable to our industry clients.

Our team has significant experience working with the steel, chemical, mining, manufacturing, aluminum, lead, oil and gas, power generation and pipeline industries, among others. We also regularly advise our clients on the development of sustainability programs related to air emissions that minimize the legal risks that can arise from these programs. BakerHostetler’s cross-office team includes Chambers-ranked practitioners in the Rocky Mountain West, Texas, the Midwest and Washington, D.C.

  • Represented a mining company in a successful U.S. Supreme Court litigation concerning the regulation of carbon dioxide under the CAA, establishing the “Major Questions Doctrine” in one of the most complex and influential decisions impacting administrative law in the past 30 years.
  • Led CAA permitting efforts, resulting in the successful financing, construction and operation of four new steel and other metal mills in the U.S., representing billions of dollars in capital investments, and successfully defended these permits in state and federal administrative proceedings and courts.
  • Represented one of the 10 largest refineries in the world in high-profile environmental enforcement actions brought by the U.S. Environmental Protection Agency (EPA) and the Department of Justice in a bankruptcy context and negotiating a plan for the decommissioning and resolution of enforcement issues to permit the sale of assets.
  • Represented manufacturers in multiple cases by obtaining dismissals of citizen and competitor suits alleging violations of the CAA and successfully defending those decisions on appeal.
  • Represented petroleum refineries in litigation challenging EPA’s denial of a small refinery hardship waiver from the CAA Renewable Fuel Standard program.
  • Provide comprehensive litigation and risk mitigation services to a client using ethylene oxide, including but not limited to defending toxic tort lawsuits, amending air permits for many facilities across several states, developing alternatives to emissions testing and analyzing and advising on regulatory, public health and litigation (including contractual, employer and toxic tort) risks to support ongoing and future operations.
  • Advise numerous on- and off-road light- and heavy-duty vehicle and engine manufacturers on compliance with federal Title II and California Air Resources Board certification regulations, defect reporting, recalls, field fixes and on-board diagnostics integration.
  • Represent the first plastic recycling facility to achieve commercial operation using pyrolysis technology and addressing various air permitting, compliance testing and third-party and compliance challenges associated with an innovative and emerging technology.
  • Assess the applicability of new and existing regulations to new processes and equipment, advise on NSR Prevention of Significant Deterioration applicability to facility modifications, develop and oversee management of change policies and procedures, obtain “as built” permit revisions for greenfield facilities, defend “single source” determinations in permitting and prepare case-by-case maximum achievable control technology determinations.
  • Represent states and industrial clients in CAA administrative proceedings and litigation, including preparing comments on proposed actions and contesting them in courts of appeals, including Biden-era rules such as EPA’s “good neighbor” obligations (i.e., regional ozone transport), new source performance standards for the steel and chemical manufacturing industries, the Mercury and Air Toxics Standards Risk and Technology Review, Section 111(b) standards for greenhouse gas emissions from new and existing fossil fuel-fired power plants and revisions to the scope of “Applicable Requirements” for purposes of EPA review of state and federal operating permits.
  • Advise a client on efforts to obtain third-party certification of its sustainability practices, including but not limited to participation in audits; the vetting of Scope 1, Scope 2 and Scope 3 emissions estimates; and the development and implementation of emissions reduction policies.

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