Particle size effects of contaminated gravel sand on the leaching of inorganic constituents in column percolation tests

Abstract

Applicability of conventional leaching tests is an important issue for characterizing the leaching behavior of coarse-grained soil, since sample preparation including particle size control may affect the testing results. This study investigated the effects of maximum particle size of a sand gravel soil on the leaching behavior of arsenic as well as major cations. Overall, leaching concentrations of these inorganic constituents were higher in the sample containing more fine particles. However, the grading effect on the void ratio of the specimens is influential to the cumulative release since the void ratio affects both the equilibrium concentrations before percolation, as well as the flow velocity during percolation, which was observed in potassium ion release.