David E. Ellis Ph.D., P.G. is a Principal Consultant in DuPont's Corporate Remediation Group in Wilmington, Delaware. He leads the company's programs in remediation technology. Dave is also Chair of the EPA RTDF Consortium on Bioremediation of Chlorinated Solvents, a member of the National Research Council on Natural Attenuation, a member of the Board of Directors of the ITRC, and sits on several university committees. Dave received his Ph.D. at Yale University in 1978, and has published over 40 articles in environmental technology, geochemistry, and high temperature thermodynamics.