Study on speciation and Distribution characteristics of Heavy Metals in soil around typical Coal Gangue in Fengfeng Mining Area

Taking the coal gangue mountain in Hebei Fengfeng mining area as the research object, 30 soil samples were collected in the east, southeast and southwest directions within 300m of the coal gangue mountain boundary, and the coal gangue stacking were used to study the heavy metal pollution of the surrounding soil. The heavy metal form of soil around coal gangue was extracted by Tessier five-step continuous extraction method, and analyzed its morphological characteristics and biological activities. The results showed that: (1) Hg and Cr were mainly retained in the soil as residual, which did little harm to the environment; Pb and Cd are mainly exist in the soil in residual and bound to iron-manganese oxide; Cu is mainly exists in the soil in residual and bound to organic matter. (2) According to the analysis of the available coefficient and migration coefficient of soil heavy metals in soil, Cd belongs to medium risk. Cu and Pb are low risk, and Cr and Hg are considered as risk-free because their available state content is lower than the detection limit. (paper)