Charles Johnson is the Solid Waste Unit Leader at the Colorado Department of Public Health and Environment in Denver, Colorado. Charles has worked with the Hazardous Materials and Waste Management Division since 1991. He issues hazardous waste operating and post-closure permits as well as oversees corrective action site inspections and characterization, remediation, and post-closure care projects. Charles routinely presents at conferences and is an instructor for ITRC's training courses on alternative landfill technologies and ecological reuse. Charles has been active in the ITRC since 2000 serving as Colorado's ITRC Point of Contact, a DNAPLS Surfactant and Cosolvent subteam leader, and team leader for both the ITRC Alternative Landfill Technologies team and the ITRC Ecological Reuse team. Charles earned a bachelor's degree in geology from the University of Texas in Austin in 1980, a master's in geology from Texas A&M in College Station, Texas in 1983, and a master’s in civil engineering from the University of Colorado in Denver, Colorado in 2005.