Dr. George Nakhla is a Professor and Salamander Chair in Environmental Engineering in the Department of Civil and Environmental Engineering at Western University. He has worked for many years on the biological treatment of toxic organics. Dr. Nakhla’s research activities in this area have significantly expanded to include the investigation of impact process parameters on the efficiency of in-situ bioremediation of gasoline compounds, the development of novel bioremediation approaches, and biological treatability of PCBs sludges. Dr. Nakhla has been contributing for many years to the development of better understanding and predictive models for simultaneous biological and physiochemical removal of contaminants in fluidized-bed granular activated carbon reactors. He was among the first researchers who delineated the impact of surface chemical reactions on adsorption of various organics on activated carbon. He also developed a reactor model that incorporates the phenomena of simultaneous biodegradation of multiple substrates and the competitive adsorption in fixed film biological reactors.