Simon Thomas obtained his M.Sc. in environmental engineering from the University of Alberta following a B.A.Sc. in civil engineering from the University of Waterloo. His Master's research with Dr. Hrudey for the interdisciplinary research program of the Eco-Research Chair in Environmental Risk Management provided the foundations for this book. Simon currently works with Aqualta, which treats and supplies drinking water for the city of Edmonton and surrounding communities. Steve Hrudey obtained his M.Sc. and Ph.D. in public health engineering from the Imperial College Science, Technology and Medicine of the University of London. Dr. Hrudey is a Professor of Environmental Health Sciences in the Department of Public Health Sciences of the University of Alberta and has held the Eco-Research Chair in Environmental Risk Management since 1993. He has been active in research, teaching and professional practice in environmental science and health for more than twenty-five years, with an emphasis on risk assessment and management over the past ten years.