MODELING AND IMPACT OF METAL ACCUMULATION IN BOTTOM SEDIMENTS OF WET PONDS

Data from thirteen sites located in south and central Florida were use d to evaluate the heavy metal accumulation in the bottom sediments of wet detention ponds. Accumulation rates were calculated for cadmium, c hromium, copper, iron, nickel, lead and zinc. Copper, zinc and lead ac cumulations account for 75 percent or more of the total heavy metal ac cumulation, excluding iron. Relative accumulation rates for copper, zi nc and lead averaged 1:4.8:11.8, respectively. Linear and non-linear p redictive equations based: on the ratios of total drainage area to pon d surface area were developed for copper, lead and zinc accumulation r ates. The impact of sediment heavy metal content on benthic organisms was evaluated for nine of the study ponds. Benthic organisms in the bo ttom sediments showed less species diversity than typical freshwater l akes and copper appeared to be the most detrimental metal to benthic o rganisms.