Thor Ketzback concentrates his nationwide practice in all areas of environmental and health and safety law, with a specific focus on Clean Air Act (CAA) counseling, permitting and litigation. Utilizing his environmental background in private practice and government service, he has served as environmental counsel for a wide array of clients including those within the energy, manufacturing, chemical and agricultural production sectors.

Mr. Ketzback’s CAA practice routinely involves counseling, permitting and litigation matters relating to the New Source Review (NSR), New Source Performance Standards (NSPS), National Emissions Standards for Hazardous Air Pollutants (NESHAPs or MACT) and other complex CAA programs. He also advises clients on new and emerging CAA and environmental programs relating to Climate Change, sustainability and market-based regulatory mechanisms.

Mr. Ketzback also represents a diverse spectrum of alternative and renewable energy clients, including projects in the following sectors: co-generation and biomass, independent power producers, waste to energy, coal to liquid, ethanol, biodiesel, district heating and cooling, and wind. His work in this arena involves all aspects of environmental and general legal counseling, including performing due diligence, securing permits, interfacing with potential investors, the general public, and political stakeholders, coordinating public communications strategies, and developing regulatory compliance strategies.

Prior to entering private practice, Mr. Ketzback was an Associate Regional Counsel with the EPA where he advised the Regional Administrator on various issues related to multi-media federal environmental law enforcement, compliance and permit issuance. As an attorney for the EPA, he worked extensively on the coal-fired power plant initiative which involved complex litigation surrounding the applicability of NSR and NSPS to the electric utility industry. Additionally, he conducted enforcement actions involving all environmental media and developed policies and strategies relating to CAA and brownfield programs.

Civic Involvement & Honors

    • Illinois Super Lawyers, 2013-2015
    • Leading Lawyers Network
    • Chambers USA, 2008-2018
    • The Best Lawyers in America®, 2019
    • Chambers USA, 2008-2018
    • The Best Lawyers in America®, 2019
    • The Best Lawyers in America®, 2019
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Professional Affiliations

    • American Bar Association
    • Asian American Bar Association
    • Chicago Bar Association
    • Asian American Bar Association
    • Chicago Bar Association
    • Chicago Bar Association
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  • "CAIR Decisions Create Regulatory Uncertainty and Require A Quick Solution," Trends, January/February 2009
  • "Environmental Updates," U.S. Clean Heat & Power Association, 2006 through 2008
  • "New Illinois Electricity Legislation: Government-Brokered Rate Relief Encourages Sustainable Energy Development," Client Bulletin, Sept. 10, 2007
  • "U.S. Supreme Court Ruling Clears the Road for Greenhouse Gas Regulation of New Automobiles," Client Bulletin, April 13, 2007
  • "U.S. EPA Proposed Rulemaking Promotes Production and Use of Renewable Fuels," Client Bulletin, Oct. 19, 2006
  • "New Source Review: Navigating the Clean Air Act With Half A Paddle and a Broken Compass," EPA Administrative Law Reporter, January-February 2005
  • "Superfund or Sewerfund? POTW Liability under CERCLA," Water Environment & Technology, April 1997

Speaking Engagements

  • “Clean Water Act Permit Shield Developments,”  National Lime Association, 2014
  • “EPA’s SIP Call Proposal to Address Startup, Shutdown & Malfunction Rules,” National Lime Association, 2013
  • “SO2 NAAQS Update,” Chemical Industry Council of Illinois, 2012
  • “Unprecedented U.S. EPA Air Regulatory Initiatives & Enforcement...Issues that Impact Your Business Operations Now & In the Future,” Sustainability and Environmental, Health & Safety Symposium, 2011
  • “Financing the Clean Tech Sector, Issues & Opportunities,” Bryan Cave & Cora Capital Advisors Conference (Closing Remarks), 2010
  • “Financing the Clean Energy Sector: Issues and Opportunities,” September 2010
  • “Midwest Clean Tech 2010,” Smart Grid Panel (Moderator), 2010
  • "Midwest Clean Tech 2009," Combined Heat and Power Panel (Moderator), 2009
  • "The Politics and Practicality of Climate Change," CLE for Fortune 200 Manufacturer, 2009
  • "Proposed Greenhouse Gas Reporting Rule: Transitioning Climate Change Regulation from Concept to Reality," CLE for The Seminar Group, 2009
  • "Federal and State Climate Change Frameworks and the Clean Air Act," CBA CLE Seminar, 2009
  • "Impending Climate Change Law: How to Prepare for the New World of Carbon Regulation," Bryan Cave Webinar, 2009
  • "Clean Technologies and Sustainability: Global Perspectives & Opportunities," Alternative and Renewable Energy Panel (Moderator), 2008
  • "The Business of Sustainability," CLE for Fortune 100 Retailer, 2008
  • "What is Sustainability?," DePaul University, 2008
  • "Climate Change Reporting Requirements and Developments," U.S. Clean Heat and Power Association Annual Conference, 2007
  • "Climate Change Review," Internal CLE Course, 2007
  • "Illinois Air Regulatory Update," Trinity Consultants Luncheon, 2007
  • "Environmental Issues Relevant to U.S. CHPA Membership," U.S. Clean Heat and Power Association, 2006
    Alternative Energy Conference, Lake Michigan Air Waste and Management Association (Organizer), 2006
  • "Update on EPA’s NSR Coal-Fired Power Plant Initiative," CBA YLS Environmental Law Section, 2000
  • "Strategies for Negotiating with EPA," CBA YLS Environmental Law Section, 1999
  • "Environmental Justice and Brownfield Policies," Valparaiso University, 1999
  • "Environmental Justice and Title VI," Brownfield Conference, State Bar of Michigan, 1998