Understand the Environmental Processes That Control Groundwater Quality The integration of environmental isotopes with geochemical studies is now recognized as a routine approach to solving problems of natural and contaminated groundwater quality. Advanced sampling and analytical methods are readily accessible and affordable, providing abundant geochemical and isotope data for high spatial resolution and high frequency time series. Groundwater Geochemistry and Isotopes provides the theoretical understanding and interpretive methods and contains a useful chapter presenting the basics of sampling and analysis. This text teaches the thermodynamic basis and principal reactions involving the major ions, gases and isotopes during groundwater recharge, weathering and redox evolution. Subsequent chapters apply these principles in hands-on training for dating young groundwaters with tritium and helium and ancient systems with radiocarbon, radiohalides and noble gases, and for tracing reactions of the major contaminants of concern in groundwaters. Covers the basics of solutes, gases and isotopes in water, and concentration-activity relationships and reactions Describes tracing the water cycle, weathering, and the geochemical evolution of water quality Explores dating groundwater as young as a few years to over hundreds of millions of years Uses case studies to demonstrate the application of geochemistry and isotopes for contaminated groundwaters Accessible to consultants and practitioners as well as undergraduates, Groundwater Geochemistry and Isotopes presents the basics of environmental isotopes and geochemistry, and providesyou with a full understanding of their use in natural and contaminated groundwater.