METALS REMOVAL TECHNOLOGIES FOR STORMWATER

Abstract

This study, on innovative methods for the capture of metals from stormwater, focused on two major areas of investigation: media filters and swales. The test water for both the filters and the swales was a stormwater which was collected from a parking lot during wet weather events. The characterization of the stormwater showed that the most prevalent metals detected in the runoff were iron, zinc, copper and small amounts of particulate bound lead. Ranges of metals were within national ranges reported by other studies. In the filter studies twelve media were chosen for initial evaluation. Equilibrium and kinetic studies were completed on these media to assess their performance in capturing metals from urban runoff. The three best performing media: peat-sand mix, compost, and zeolite were then selected for in-depth study. The results of this investigation emphasize the importance of characterizing the stormwater before selecting a treatment media since the type and quantity of metals, pH, and other runoff characteristics can vary a great deal between sites. Additionally determining the range of metal concentrations of the runoff to be treated is crucial to selecting the best media, since the removal efficiencies of the media relative to each other changed with