Although microorganisms can be found virtually anywhere on our planet, from clouds to soils to oceans, they are often poorly understood when examining issues related to groundwater and water wells. Focusing on the impact of microorganisms on groundwater and water wells, Practical Manual of Groundwater Microbiology, Second Edition presents over 75% new material to offer a comprehensive, up-to-date guide on the subject. The first eight chapters provide an overview of microbiology and its importance in groundwaters, exploring natural filters that develop around wells, various bacteria, molds, viruses, sampling procedures, biofouling, biofilms, sequestration strategies, rehabilitation/regeneration practices, and flooding risks. The book also contains a chapter that functions as a self-contained guide, with 79 descriptive illustrations of important concepts integral to the understanding of microbes in groundwater. Numerous appendices, some new to this edition, supply detailed information on more specialized topics, such as microbiological test methods, water sample protocols, regulatory considerations concerning the use of phosphorus in wells, and the application of vegetable oil to lubricate pumps. Chronicling the significant progress made in the field since the publication of its predecessor, this edition provides practical approaches for evaluating the effects of microorganisms and their activities on groundwater and water wells.