Abstract: As an inevitable solid waste during the mining process， the permeability/leaching property of tailings is normally considered as one of the most critical factors for environmental pollution. In this study， a self-designed infiltration/leaching device was designed to conduct the permeability tests of tailings from a copper mine. And the influences of chemical factors，dry density and pH on the permeability property of tailings were investigated. In order to study the environmental pollution caused by tailings leaching， the visual Moldflow software was applied to simulate the migration process of Cu2+ in tailings pond. Moreover，based on the retention concept of engineered barrier，a contaminant transport model was established to simulate and assess the control effects of heavy metal pollution.Test results revealed that:①The permeability coefficient of tailings gradually increased with the decrease of pH value，and the maximum permeability coefficient can increase 1~2 orders of magnitude.②Under the environment of saline solution，as the NaCl concentration increased， the permeability coefficient firstly increased and then decreased. ③The simulation results implied that the engineered barrier could chronically and effectively retain the pollution source， and could be considered as an important preventing and repairing method for the mine environment pollution. Based on the above analysis results， the engineering measures were proposed for the prevention of heavy metal pollution in mines， and these measures could provide imported guidance for relative engineering practices.

Key words: deep mining, tailings, chemical factors, permeability characteristics, numerical simulation, pollution control