This book describes the general behavior of groundwater in plains, either of alluvial, deltaic, piedmont, intermountain and coastal nature. It also proposes the use of specific methods, techniques and cartography, to elucidate in detail, their dynamical and chemical properties. It also suggests a methodology for hydrogeological studies and analyzes the essential methods for evaluating groundwater vulnerability to contamination. The book contains useful color illustrations, figures and tables, as well as a comprehensive bibliography for further research on certain specific issues.