About People

Stephen Ellingson

Stephen Ellingson, PhD

Associate Vice President

Stephen has more than 30 years of diverse environmental experience working in consulting, private industry, and for a state regulatory agency. He specializes in contaminant-specific projects that involve of the fate and transport and toxicity of specific constituents such as per-and polyfluoroalkyl substances (PFAS), volatile organic compounds (VOCs), methyl tertiary-butyl ether (MTBE), polyaromatic hydrocarbons (PAHs), chromium lead, mercury, coal-combustion residuals (CCR) and radionuclides.

Stephen has extensive experience with investigation and remediation on Superfund sites, including conducting removal actions and remedial investigations, engineering evaluations and cost analyses, feasibility studies and applicable or relevant and appropriate requirements (ARARs) waivers. He also has experience evaluating water quality, including surface and groundwater quality and contaminant migration, safe drinking water compliance, and interactions between surface water and groundwater. 


  • PhD, Arizona State University 
  • MA, St. Cloud State University 
  • BA, Gustavus Adolphus College 


  • Certified Groundwater Professional (1614)

Practice Area

Environmental Sciences

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