A thorough, up-to-date guide to groundwater science and technology Our understanding of the occurrence and movement of water under the Earth's surface is constantly advancing, with new models, improved drilling equipment, new research, and refined techniques for managing this vital resource. Responding to these tremendous changes, David Todd and new coauthor Larry Mays equip readers with a thorough and up-to-date grounding in the science and technology of groundwater hydrology. Groundwater Hydrology, Third Edition offers a unified presentation of the field, treating fundamental principles, methods, and problems as a whole. With this new edition, you'll be able to stay current with recent developments in groundwater hydrology, learn modern modeling methods, and apply what you've learned to realistic situations. Highlights of the Third Edition * New example problems and case studies, as well as problem sets at the end of each chapter. * A special focus on modern groundwater modeling methods, including a new chapter on modeling (Chapter 9), which describes the U. S. Geological Survey MODFLOW model. * Over 300 new figures and photos. * Both SI and U.S. customary units in the example problems. * Expanded coverage of groundwater contamination by chemicals. * New references at the end of each chapter, which provide sources for research and graduate study. Student and instructor resources for this text are available on the book's website at www.wiley.com/college/todd.

From one of the most prestigious nonprofit organizations devoted to environmental issues comes a clear, practical, and rational overview of the relationship between consumers and the environment. Paper or plastic? Bus or car? Old house or new? Cloth diapers or disposables? Some choices have a huge impact on the environment; others are of negligible importance. To those of us who care about our quality of life and what is happening to the earth, this is a vastly important issue. In these pages, the Union of Concerned Scientists help inform consumers about everyday decisions that significantly affect the environment. For example, a few major decisions--such as the choice of a house or vehicle--have such a disproportionately large affect on the environment that minor environmental infractions shrink by comparison. This book identifies the 4 Most Significant Consumer-Related Environmental Problems, the 7 Most Damaging Spending Categories, 11 Priority Actions, and 7 Rules for Responsible Consumption. Learn what you can do to have a truly significant impact on our world from the people who are at the forefront of scientific research.