HYDRAULIC BARRIER AND CESIUM SORPTION PERFORMANCES OF GEOSYNTHETIC CLAY LINERA AMENDED BY ZEOLITE

Abstract

Hydraulic conductivity and cesium sorption performance of zeolite-amended GCLs were determined by performing batch and column sorption tests. Particularly, the effects of sodium, potassium and calcium ions in waste leachate on both hydraulic barrier and cesium (Cs) sorption performances of the GCLs were evaluated. Batch sorption test results indicated that the Cs distribution coefficient (Kd) of the zeolite was not lowered against the higher concentrations of calcium ions, unlike that of the sodium-bentonite. In the column sorption tests, comparing with a conventional GCL, zeolite amended GCLs maintained excellent cesium sorption performance even when 0.1 mol/L-calcium solution was permeated, while permeation of the waste leachate containing 0.11 mol/L- potassium ion allowed the release of Cs though the GCLs.