SOIL STRUCTURE CHARACTERISTICS OF UNDISTURBED DECOMPOSED GRANITE SOIL AND THEIR EFFECTS ON COPPER PLUME MIGRATION

摘要

The influence of soil structure on the breakthrough of a copper contaminant plume when passing through undisturbed decomposed granite soil was studied. The copper concentration was measured in real time by means of two fibre-optic sensors with reflective-type located on either side of the undisturbed granite soil sample. The adsorption properties were also studied by the column and batch testing. It was found that the copper adsorption of both slightly and severely decomposed granite soil followed a Freundlich model, and the measured values of both samples corresponded well with the calculated values. In this paper, the experimentally obtained copper dispersion characteristics are compared with the contour and velocity vectors by FEM analysis using the advection-dispersion equation. It is shown that the copper concentration and velocity distributions in the severely decomposed granite soil are dependent on the usual parameters, such as the modified coefficient of permeability, retardation factor, dispersion length and dis-persivity, which control the flow into the macro (>0.1 μm) and meso pores (0.002-0.1μm).