Mark A. Thimke

Retired Partner


Mark A. Thimke is a partner and environmental lawyer with Foley & Lardner LLP. His practice encompasses all major environmental programs, including hazardous waste, Superfund, the Clean Air Act, air toxics, and wastewater. Mark has been involved in Superfund matters ranging from landfills, municipal well fields, and the investigation and cleanup of river and harbor sediment remediation areas, representation of dischargers on issues involving water toxics limitations, and the development of a detailed anti-degradation policy, and work on several major air enforcement actions. He is a member of the firm’s Environmental Regulation Practice and the Energy Industry Team.

Mark helped secure the first Plantwide Applicability Limit (PAL) permit in Wisconsin, for Bemis Co. Inc. A PAL permit applies an annual emissions limit for pollutants to an entire facility, eliminating the need for multiple limits throughout the facility and more crucially, allowing companies to avoid going through the time-consuming NSR permitting process each time it expands operations.

Environmental Criminal Investigation Experience

Mark has been involved in a number of criminal investigations in the environmental area, and regularly conducts internal investigations in connection with alleged criminal activity. The following are several investigations in which Mark has been involved:

  • Criminal investigation associated with the alleged burial of waste-containing drums prior to plant inspection by senior management
  • Criminal investigation associated with the falsification of wastewater discharge monitoring reports
  • Internal investigation and grand jury investigation into the alleged use bypassing of wastewater discharge monitoring devices
  • Criminal investigation alleging improper removal of asbestos

Thought Leadership

Mark has participated in several small group workshops with personnel from the United States Environmental Protection Agency, which developed recommendations for improving the Superfund cleanup process, cost allocation, and dispute resolution methods. At the state level, he has served on the Wisconsin Department of Natural Resources NR 700 External Advisory Committee, which worked for two years on the development of a comprehensive state cleanup code. He continued his work in this area as a member of a select focus group that worked on the development of soil cleanup standards and a comprehensive remedy selection process.

Mark has lectured on environmental matters throughout the country and was a principal instructor during a week-long session on environmental compliance at a federal facility in the Republic of the Marshall Islands. He also is an author of the Wisconsin section of the Matthew Bender publication, State Environmental Laws.


  • Named to The BTI Consulting Group’s coveted BTI Client Service All-Stars list for 2014; This elite group of standout attorneys — identified solely through unprompted client feedback — are recognized as delivering the absolute best client service
  • Peer review rated as AV Preeminent®, the highest performance rating in the Martindale-Hubbell® Peer Review Ratings™ system
  • Selected by his peers for inclusion in The Best Lawyers in America© in the fields of:
    • Environmental Law (1989 - 2022)
    • Litigation - Environmental (2011 - 2022)
    • Natural Resources Law (2012 - 2022)
  • Selected for inclusion in the list of Wisconsin Super Lawyers® (2005 - 2008 and 2010 - 2016)
  • Recognized in Chambers USA: America's Leading Lawyers for Business in the practice area of Natural Resources & Environment (2010 - 2021)

Professional Memberships

  • Member of the Environmental Law Section of the Wisconsin Bar
  • Member of the Natural Resources Section of the American Bar Association


  • University of Wisconsin Green Bay (B.A., summa cum laude, 1976)
  • Duke University (J.D., 1979)
    • Elected, Order of the Coif
    • Staff and editorial board member on the Duke Law Journal