Dimensional Analysis of Colloid-Facilitated Ground-Water Contaminant Transport

Abstract

Mobile subsurface colloids can carry ground-water contaminants sorbed onto their surfaces to far greater distances than predicted using a conventional advective/dispersive transport equation with normal retardation values. In this study, we present a dimensional analysis of colloid-facilitated ground-water contaminant transport. The significance of the contaminant distribution coefficient with colloids and the colloid distribution coefficient with the solid matrix on the retardation coefficient is demonstrated. Figures plotted in terms of dimensionless parameters show that the smaller the sorption of contaminant with colloids, the smaller the effect of colloid presence on contaminant transport. The effect of retardation coefficient on the normalized contaminant concentration profile is illustrated in terms of dimensionless parameters. It has been demonstrated that a reduction in contaminant retardation coefficient in the presence of colloids is accompanied by a corresponding reduction in the modified hydrodynamic dispersion coefficient. Furthermore, the relation between the change in the retardation coefficient and modified hydrodynamic dispersion coefficient has been obtained for different values of the colloid distribution coefficient with the solid matrix. As the retardation coefficient of contaminant in the presence of colloids,