Walt McNab is an environmental scientist with Lawrence Livermore National Laboratory. He has participated in a variety of groundwater contamination studies, including plume analyses, modeling, and treatment technology development. Dr. McNab holds a B.A. in geology and an M.S. and Ph.D. in hydrogeology from U.C. Berkeley. His research interests include reactive transport modeling, evaluation of bioattenuation processes through geochemical characterization, and statistical analyses of groundwater contaminant plume populations.