The use of models to provide additional details on contaminant fate and transport has rapidly increased in the past 3 decades. The increasing global recognition of the potential risks associated with surface water or ground water contamination and speciÞc environmental regulations implemented after 1980 have demanded a more accurate understanding of these risks as they relate to human health and the environment. Modeling has become an invaluable tool in providing the necessary information to understand the risks associated with contaminants in complex environments with complicated environmental processes
