An Assessment of Ariake Clay For Its Potential Use As A Landfill Barrier

An assessment of the potential use of a typical Japanese marine clay, Ariake clay, as a soil barrier material in landfills, was presented in this paper. Two types of heavy metals, Cd²⁺ and Pb²⁺, were selected as key contaminants for a laboratory diffusion test. Using commercially available contaminant transport software, the effective diffusion coefficients and partition coefficients of both Cd²⁺ and Pb²⁺ were back-calculated from the results of the diffusion test. The effective diffusion coefficients were found to be consistent with previously published values. The high retained percentage of Cd²⁺ and Pb²⁺ in the Ariake clay specimen indicated that the Ariake clay might be used as a good barrier material in landfills. With the derived effective diffusion coefficients and partition coefficients, the impacts of Cd²⁺ and Pb²⁺ on the water quality of the aquifer which underlies an assumed landfill were numerically assessed using the ID diffusion transport theory.