Pesticides in groundwater can contaminate drinking water and threaten the health of communities. How does this contamination occur and what should be done about this pressing problem? This new book uses a case-study approach to describe the discovery of the problem in four major agricultural states, to summarize the most recent data on the problem, and to review the status of the problem from both technological and policy perspectives. It also addresses the controversial questions of what levels of residues are acceptable, who should bear the costs of drinking water that is already contaminated, and how federal scientific resources can best be used to aid state initiatives in addressing this problem.