This book describes a major method in modeling the flow of water and transport of solutes in the subsurface, a subject of considerable interest in the exploitation and preservation of water resources. The stochastic approach allows the uncertainty that affects various properties and parameters to be incorporated in models of subsurface flow and transport. These much more realistic models are of greater use in, for example, modeling the transport and buildup of contaminants in groundwater. The book is a valuable reference work for graduate students, research workers and professionals in government and public institutions, and for those interested in hydrology, environmental issues, soil physics, petroleum engineering, geological engineering and applied mathematics.