Dr. Charles Schaefer is an environmental scientist and the director of CDM Smith's Bellevue, Washington research and testing laboratory. His research expertise includes pore-scale diffusion and mass transfer processes, in situ bioremediation, treatment of emerging contaminants including perfluorinated compounds such as perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) and electrochemical treatment of drinking water. Charles has served as a principal investigator on several research grants, many of which have focused on chlorinated solvents in bedrock systems. He has authored over 40 peer-reviewed papers and is an active member of the Interstate Technology and Regulatory Council (ITRC). In addition to his research, Charles also serves as a technical consultant on several federal and private sector projects for CDM Smith, many of which address chlorinated solvents in complex geological settings.