The three-dimensional visualization of atrazine and deethylatrazine in a reservoir was
determined by five "snapshots" over a one-year period using immunoassay analyses, confirmed
by gas chromatography-mass spectrometry and visualized with a three-dimensional computer
program. The surveys were conducted in Perry Lake in Kansas and showed that spring runoff
laden with triazine herbicides entered the reservoir and did not mix immediately. Concentrations
varied threefold between the inlet and the public water supply intakes located at the opposite
end of the reservoir. The concentration range in the outflow varied much less than the
concentration in the reservoir because of mixing throughout the season near the dam and
outflow. A major conclusion from the study was that multiple analyses by a low-cost
immunoassay technique coupled with computer visualization software gave a good three-dimensional
view of the mass of herbicide present in a drinking water reservoir. Includes 33 references, table, figures.