Approximately 21 billion pounds of pesticides have been applied to United States farmlands since 1964. In agricultural regions, high pesticide concentrations occur in surface and groundwaters because of spring runoff or leaching. Because many of these compounds pose health risks, the United States Environmental Protection Agency (USEPA) has a mandate, under the Safe Drinking Water Act Amendments of 1986, to regulate several of these compounds. Others will be undergoing regulatory scrutiny because they are included in EPA's First Drinking Water Priority List, as well as the National Pesticide Survey. In an attempt to understand possible compliance problems, an investigation was conducted on river water containing Alachlor, Altrazine, Cyanazine, Linuron, Metolachlor, Metribuzin, and Simazine. The purpose of the study was to determine to what extent several treatment processes such as reverse osmosis were able to remove pesticides from the Sandusky River at the Tiffin, Ohio Water Treatment Plant. In addition pilot scale studies were conducted using several different types of polymeric membranes to remove pesticides from spiked groundwater.