ABSTRACT
Arsenic (As) is naturally found in association with gold minerals widely exploited in Minas Gerais, Brazil since the 17th Century, mainly at the region named Iron Quadrangle (IQ). As a consequence of this economic activity, large amounts of As containing mine tailings were, and still are, discharged. Biological approaches are being tested to decontaminate As containing wastes. Soil-flushing technique, using biosurfactants, was tested to promote As mobilization from contaminated tailing samples collected at an abandoned gold mine. The optimum condition for biosurfactant production by the chosen microbial consortium was determined. The efficiency of the biosurfactant containing supernatant was tested against other extractants: distilled water, CaCl2, SDS and Saponin in sequential extractions. The cumulative arsenic removal was approximately 25% in the column soil-flushing tests, running at room temperature, pH 11.0.
