ABSTRACT
Since the discovery of agricultural chemicals in drinking water wells in 1979, considerable progress has been made in understanding the movement and degradation of agricultural chemicals in the environment. Instances of agricultural chemicals in ground water are typically grouped into two categories. The two categories are non-point source and point source. Non-point source is used to describe those instances where residues of agricultural chemicals enter ground water as a result of normal movement through the soil profile underneath a properly treated agricultural field. Many of the isolated instances of agricultural chemical residues in drinking water wells result from point sources. Unlike management practices for preventing point source residues, management practices for preventing non-point source residues must be developed for a specific agricultural chemical, crop, and set of environmental conditions. Probably the most significant advance in ground water-related research has been the improvements in analyzing soil and water samples.
