Occurrence of Pesticides in Ground Water of the North Platte Natural Resources District, Nebraska, 2002

Ground water is the source of drinking water for all residents of the North Platte Natural Resources District (NPNRD). Most of the drinking water in the NPNRD comes from unconfined aquifers that are part of the regional High Plains aquifer. The water tables of these local aquifers lie close to the land surface. As a result, the aquifers can be affected by infiltration of irrigation waters that are prone to contain contaminants. Once in the aquifer, contaminants can adversely affect drinking-water supplies. In 2002, the U.S. Geological Survey (USGS) and the NPNRD began a cooperative study to determine whether or not 112 pesticides and selected degradation products occur in ground water of the NPNRD. Forty-one monitoring wells at 23 sites throughout the NPNRD were selected for sampling to determine the areal occurrence of pesticides. This fact sheet summarizes the results of the 2002 sampling.