Investigation of natural attenuation and bioaugmentation techniques in remediate heavy metal contaminated sediments

Abstract

An investigation of natural attenuation as well as application of bioaugmentation techniques in reduction of heavy metals in contaminated sediment is studied. Five elements were chosen for this study namely zinc (Zn), lead (Pb), ferum (Fe), cadmium (Cd) and copper (Cu). Both techniques have been applied to sterilized and non-sterilized sediments with different dosage of bacteria inoculum (1 mL and 2 mL of 108 cell/mL microbes). The percentages of concentration reduction in sediment in the relative order as follow: Cd>Pb>Zn>Cu>Fe in natural attenuation. For augmentation technique, Cd reduction was the highest at range between 76.86- 92.37% while Fe was the lowest at range between 4.19-10.06% for addition of 1 mL and 2 mL of bacteria inoculate in both sterilized and non-sterilized sediments.