The impact of mining activities on sediment quality in the seafloor around Southeast of Sulawesi

Research of heavy metals content in sediments was carried out in April 2006 on the bottom sea of Buton, Kabaena, and Muna islands. This study was aimed to determine the content of heavy metals Cd, Cu, Ni, Pb, and Zn and to predict the quality of the sediments by employing indices analysis. Sediment samples were taken using a grab at 8 stations. Heavy metal content was analyzed using AAS. Three indices are exercised to analyze the metal content in the sediment, that are contamination factors, geoaccumulation index, and pollution load index. The computation of contamination factors showed an average value of less than 1, namely Pb= 0.236, Cd= 0.269, Cu= 0.048, Zn= 0.346, and Ni= 0.986. Meanwhile, the geoaccumulation index values were less than 1, the value for Pb= -3.836, Cd= -2.878, Cu= - 5.061, Zn= -2.430, and Ni= -1.002. The pollution load index value is 0.201. These values which were less than 1 implied low level of pollution in the area. Thus, according to the analysis, the sediments in these three waters are still natural and not polluted.