Published in 1991, the first edition of "The Practical Handbook of Ground-Water Monitoring" quickly became the gold standard reference on the topic of ground-water monitoring. But, as in all rapidly evolving fields, regulations change, technology advances, methods improve, and research reveals flaws in prior thinking. As a consequence, books that document the state of the science, even widely acknowledged definitive works, become outdated and need to be rewritten periodically to stay current. Reflecting this and renamed to highlight its wider scope, "The Practical Handbook of Environmental Site Characterization and Ground-Water Monitoring, Second Edition" provides an updated look at the field. Completely revised, the book contains so much new information that it has doubled in size. Containing the most up-to-date information available, this second edition emphasizes the practical application of current technology. It covers environmental site characterization and ground-water monitoring in great detail, from the federal regulations that govern environmental investigations, to the various direct and indirect methods of investigating and monitoring the subsurface, to the analysis and interpretation of complex sets of environmental data. Cheaper, better, faster was the mantra of the 1990s, resulting in more streamlined approaches to both environmental site characterization and ground-water monitoring, but also pitting the application of good science against the mandate to get a project done as quickly and inexpensively as possible. This book provides unbiased, technical discussions of the tremendously powerful tools developed in the last decade, helping environmental professionals strike a balance between good science and economics.