Geochemical modeling is a powerful tool for characterizing environmental site contaminations and predicting environmental impacts. This book discusses the application of geochemical models to environmental practice and studies, through the use of numerous case studies of real-world environmental problems. It will thus help students to relate class-room learning to real-life issues, and help practitioners to see more clearly the benefits of geochemical modeling for their own work. Environmental Applications of Geochemical Modeling opens with background chapters on thermodynamics, kinetics, and geochemical modeling in general. Case studies are then presented which illustrate the application of varions types of geochemical models to such diverse problems as acid mine drainage, nuclear waste disposai, bioavailability and risk assessment, mine tailings and mining waste, pit lake chemistry, deep well injection, chemical weathering, artificial recharge, landfill leachate, and microbial respiration rates. In each example the authors clearly define the environmental threat in question ; explain how geochemical modeling may help solve the problem posed ; and advise the reader how to prepare input files for geochemical codes and interpret the results in terms of meeting regulatory requirements. Models covered include speciationsolubility, surface complexation, mass transfer/reaction path, inverse mass balance, and coupled reactive transport models. The examples also demonstrate the use of many popular geochemical modeling codes such as PHREEQC, MINTEQA2, EQ3/6, and The Geochemist's WorkbenchTM. Support material for the book, including program codes, input files and exercise problems, is available on the internet. This book will serve as an advanced textbook for courses in environmental geochemistry, and as an indispensable reference for professional hydrogeologists, geochemists, engineers, and regulators, working in the environmental consulting industry.