To reveal the changes of heavy metals distribution in different reclaimed years in coal mine reclaimed areas, and evaluate the environmental pollution, in this study we chose the reclaimed areas of Heidaigou mining opencast coal mine in loess plateau region as our research object. We sampled from 0 -40 cm soil depth in different reclaimed areas, analyzed and evaluated the changes of soil heavy metals under different years after reclamation. The results showed that: As the years increased after

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... eclamation, the content of Pb, Cr, Cd and As reduced gradually from a whole respect, and the contents in topsoil were higher than subsoil. After reclamation of 15 years, its contents were lower than the primary standard of the soil environmental quality standards in China. However, the content of Hg followed an increasing trend. It increased in 0 -20 cm, and the value was higher than the secondary standard of the soil environmental quality standards in China, but lower than the primary standard. But it decreased in 20 -40 cm soil layer, its value was lower than the primary standard of the soil environmental quality standards in China. The longer of reclamation, the lower contents of heavy metals, and smaller pollution to the environment. As to the phenomenon of Hg content increasing rather than reducing, it needs further study.