Evaluation of bioremediation potential of selected soil microorganisms in removal of arsenic from contaminated soils

The main aim of this work was an experimental study of arsenic removal from buried power plant ash through biostimulation and bioaugmentation by selected types of microorganisms. The results obtained show that the efficiency of As bioleaching under laboratory conditions was low for bacteria, either by stimulating autochthonous microflora in the substrates or by augmentation with native species. This could be due to incorrect selection of representative strains, but also due to the chemical composition of nutrient media that did not contain sufficient nutrients to increase the activity of microorganisms in the substrates. The relatively high proportion of As leached after the augmentation of samples with the alochthonic species Rhodococcus sp. suggests the application of strains that were isolated in other types of contaminated environment, but because of their high adaptability and metabolism they were able to successfully introduce themselves into the environment, compete with native species to fight for nutrients and increase arsenic removal from the soil.