The hydraulic conductivity of mine leachate through the geosynthetic clay liners（GCLs） was tested using the flexible wall permeameter under different effective stresses. The result of test shows that the increase in the hydraulic conductivity of the GCL permeated with simulated mine leachate was strongly related to the effective stress applied on the GCLs. Under a relatively low effective stress of 24 kPa

the hydraulic conductivity of GCL permeated with simulated mine leachate was up to 1.52810-′ m/s

about 340 times greater than that of GCL permeated with tap water. The GCL was not able to satisfy the requirement specified in the standard for pollution control on the storage and disposal site for general industrial solid wastes. However

the hydraulic conductivity decreased to 26

21

14 and 10 times of the number for tap water when the effective stress increased to 93

162

231

and 438 kPa

respectively. All the hydraulic conductivity values of GCL obtained during these test stages were lower than the specification in standard. The results of this study indicated that the stress state for GCL expected in the field should be considered when evaluate the hydraulic performance of GCLs that considered as a liner for a tailing impoundment.