Groundwater, pesticide, water quality, nitrate, phosphate
Occurrences of pesticides in our nations ground water are on the rise. As states become aware of this problem and begin monitoring programs, incidence of contamination will probably increase. Since the problem of pesticides in groundwater is relatively new, little research has centered on the fate of pesticides after they reach the groundwater environment. In Northwest Arkansas efforts to monitor groundwater for pesticides have been small. Twenty-five springs in Northwest Arkansas were sampled in the fall of 1988, and spring of 1989. Analysis for atrazine, alachlor, metolachlor, diuron, and simazine in spring water was preformed using gas liquid chromatography and high performance liquid chromatography. No detectable residues of any of the selected pesticides were found. Northwest Arkansas is a leader in poultry production. Much of the manure from poultry houses is spread on the sourounding pastures. As this litter decomposes nitrates and phosphates are released. Nitrate and phosphate concentrations were also determined on water from the spring samples. No spring exceeded the EPA's limit of 45 mg/L for nitrate in drinking water. The highest concentration for phosphate in any spring was 1.05 mg/L.
Lavy, T. L.; Dehart, B. A.; and Mattice, John D.. 1989. Determining Pesticide and Nitrate Levels in Spring Water in Northwest Arkansas. Arkansas Water Resources Center, Fayetteville, AR. PUB138. 28