Kathryn Johnson

Kathryn Johnson

Kathryn has nearly 40 years of consulting experience applying geochemistry and geohydrology to mineral resource development. Her experience includes data collection and analysis, laboratory test design, geochemical modeling to understand baseline concentrations and in-situ geochemical changes in response to engineered and natural perturbations, water treatment, and remedial designs. She is skilled at assessing metal mobility, contaminant fate and transport, and mitigation of acid rock drainage (ARD). Her work is often governed by regulations of the U.S. Environmental Protection Agency (EPA), state agencies, and the National Environmental Policy Act (NEPA). Her projects have involved groundwater and surface water, waste rock, tailings, hazardous and solid waste, and radioactive materials. Kathryn has provided support in legal disputes of liability, cost allocation, insurance coverage, and toxic tort. She has served as an expert witness and given trial testimony.



Senior Geochemist


PhD, Geology, South Dakota School of Mines and Technology

MS, Chemistry, Iowa State University

BS, Chemistry, Black Hills State University


Barr Engineering Co.
4300 MarketPointe Drive
Suite 200
Minneapolis, MN 55435
Phone: +1 952-832-2833