Abstract: The contamination by heavy metals is a major environmental problem in urban areas near mines. The heavy metals (Cr, Cu, Ni, Pb and Zn) in various environmental mediums around a Ni-Cu mine in the City of Jinchang, Gansu Province, were analyzed using ICP-AAS. These mediums include the cultivated soils, the weathering and atmospheric deposition on waste slagheap surface, the tailings, and the sludge in the drainage ditch by the tailings. The results showed that the heavy metals in various mediums were mainly Cu and Ni, and those concentrations were, in the descending order, in ditch, tailings, slagheap and cultivated soil. In the tailings and the sludge of the ditch, the concentrations of Ni were obviously higher than those of Cu. Whereas, in the soil and the weathering and atmospheric deposition of the waste slagheap surface, the concentrations of Cu were higher than those of Ni. This means that in the first two mediums, Cu and Ni mainly originated from the tailings, while in the latter two mediums, Cu and Ni mainly came from the atmospheric deposition of airborne particles of the smelting. Cr and Zn were mainly in residual fraction, Cu was mainly in oxidizable and residual fraction, Ni was mainly in reducible and acid-soluble fraction, Pb was mainly in reducible and residual fraction.

Key words: heavy metal, chemical speciation, distribution, mine area