Treatment and management of metal-contaminated waters and wastes

We have investigated the problem arising from the coexistence of arsenic and organic substances principally in the US Superfund Sites and elsewhere. Dissolved organic ions are strong competitors to arsenates, and because of their large size and slow kinetics, arsenic removal becomes problematic. Optimum conditions for regeneration of macroporous media were determined. Waste handling processes were developed to treat and reuse spent regeneration solutions as well as to detoxify the solid waste containing arsenic and organic matter. A reagent based technology for the treatment of spent regeneration solutions by Ca(OH)₂ and MgCl₂ (or MgSO₄) was devised. Based on the results, appropriate decontamination schemes were developed for groundwater contaminated with arsenic and organic impurities.