Using fluid loss to evaluate the hydraulic conductivity of geosynthetic clay liners under mining leachates

Abstract

Geosynthetic clay liners (GCLs) are increasingly used in mining applications, their hydraulic performance need to be further assessed. In this study, the fluid loss (FL) tests of three bentonites from different GCLs were conducted under different mining leachates. The results suggest that the FL values in mining leachates greatly increased compared to those in water. The greater ionic strength of the leachates led to much higher fluid loss. The triaxial hydraulic conductivity tests using mining leachates as permeant solutions were also performed, the hydraulic conductivity (k) value increased with the increased ionic strength of the mining leachates. The relationship between fluid loss and hydraulic conductivity was also established. The k calculated from the FL test (k FL ) is in good agreement with that from triaxial hydraulic conductivity test (k Tri ). Therefore, the FL test could be considered as a quick method to evaluate the hydraulic conductivity under the studied mining leachates. This study would provide useful reference to the mining application of GCLs.