Introduction

This chapter aims to examine the regulatory and research activities leading up to and resulting from increased interest focused on ground water research on pesticides. The advantages and problems associated with using field systems to study pesticide fate and movement are considered by Dr. Jerome Weber and K. E. Keller, and by R. F. Turco and E. J. Kladivko. Turco and Kladivko provide an extensive treatise on the many factors affecting pesticide movement under field conditions. They deal in some depth with theories of the importance of preferential flow as a mechanism for rapid transit of solutes in channeled systems. Pesticides in soils from highly contaminated sites did not breakdown as rapidly as comparable sites receiving the same amounts of applied pesticide on uncontaminated soil. Thomas J. Gilding argues that the National Pesticide Survey shows that the presence of pesticide residues in ground water is not a widespread occurrence, either in the number of residues detected, their frequency or concentration.