Contamination Level of Different Chemical Elements in Top Soils of Barapukuria Coal Mine Area in Dinajpur, Bangladesh

摘要

The contents and contamination level of 17 different chemical elements (Rb, Cs, Sr, Ba, Y, Zr, Co, Ni, V, Nb, Sn, Nd, Ce, La, Pr, Sb and Th) along with major elemental composition in 19 top soils and three canal sediment samples of the Barapukuria coal mine area were studied by X-ray Fluorescence spectroscopy (XRF). The study results revealed that SiO2, TiO2, Fe2O3, MgO, CaO and P2O5 were within the limit of normal soil, while Al2O3, Na2O and K2O in soil, and MnO and Na2O in sediment samples exceeded the maximum level of normal soil. Among the metals, the contents of Rb, Cs, Zr, Sn, Ce, La, Nd, Pr and Th in most of the top soils were higher compared to Earth's crust average, while Y and Sb contents were comparatively higher in sediment samples. Mine water discharge canal sediment samples had EFc values for Sb ranged from 24.72 to 57.09, indicating very severe to extremely severe contamination due to mining activities. Similarly, EFc values varied from 5 to <20 for Sb and Zr at 10 and 12 soil sampling locations, respectively indicating moderately severe to severe pollution load of the study area. EFc values for Sn, Th, La, Ce, Cs, Pr, Nd and Y were also >5 in several soil sampling locations indicating moderately severe contamination level in the study area. The study concluded that high EFc values indicate enrichment of metals, which might be originated from geogenic sources due to coal mining and coal based power generation related activities at the study area.