This book provides a unified and comprehensive overview of physical explanations of the stochastic concepts of solute transport processes, important scaling issues, and practical tools for the analysis of solute transport.

Over the past several decades, analyses of solute migration in aquifers have widely adopted the classical advection-dispersion equation. However, misunderstandings over advection-dispersion concepts, their relationship with the scales of heterogeneity, our observation and interest, and their ensemble mean nature have created furious debates about the concepts' validity. This book provides a unified and comprehensive overview and lucid explanations of the stochastic nature of solute transport processes at different scales. It also presents tools for analyzing solute transport and its uncertainty to meet our needs at different scales. Easy-to-understand physical explanations without complex mathematics make this book an invaluable resource for students, researchers, and professionals performing groundwater quality evaluations, management, and remediation.

We present an overview of the problem of solute transport in unsaturated heterogeneous media. We first review field and laboratory observations that demonstrate nonclassical flow and transport behavior. The main physical principles causing anomalous transport regimes in fractured rock media are identified. The basic factors and physical concepts needed to describe anomalous transport in saturated and unsaturated fractured rock are discussed in detail.