Soil, with thiosulfate salts

CaCla) was then punned into the columns to leach the herbicides, and die leachate was collected in fractions and quantified for herbicide concentration on HPLC. Addition of ammonium thiosulfate to the saturated soil or sand columns essentially prevented propachlor or alachlor from appearing in the leachate, achieving 100% removal of the herbicide as conqtared with the untreated columns (Figure 7). This sinq>le demonstration indicates that diiosulfate salts may be introduced into polluted soil or aquifer systems to detoxify HOC contaminants that are otherwise diffrcult to remove. The introduction of thiosulfate salts may be easily achieved by injection through wells or by leaching in through controlled surface irrigation. 

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