William D. Ingersoll

Of Counsel

William D. Ingersoll has practiced for nearly 30 years in the areas of environmental and administrative law. During his 27 years at the Illinois Environmental Protection Agency, Mr. Ingersoll gained extensive experience with permitting decisions, regulatory enforcement, penalty assessments, Illinois Pollution Control Board litigation, and remediation enforcement in both state and federal cleanup programs.

Since joining Brown, Hay + Stephens,  Mr. Ingersoll has leveraged his unique and prodigious environmental enforcement experience to help his clients defend cases in Illinois state courts as well as administrative cases before the U.S. EPA, Illinois Pollution Control Board, Illinois EPA, Illinois Department of Public Health, and Illinois Department of Agriculture. Bill has successfully litigated administrative appeals of both state and federal agency decisions in addition to handling environmental permitting, compliance, and variance matters.


  • California, 1981
  • Illinois, 1983
  • U.S. District Court Central District of California, 1982
  • U.S. District Court Southern District of Illinois, 2012


  • McGeorge School of Law, University of the Pacific, Sacramento, California (J.D. - 1981)
  • Illinois State University, Normal, Illinois (B.S., Sociology - 1977)