CONTAMINANT TRANSPORT IN LAYERED POROUS-MEDIA .1. GENERAL-SOLUTION

Analysis of transport of contaminants in a layered aquifer system still poses significant challenges, although considerable progress has been made in the literature toward the understanding of this problem. In this study, an analytical approach is chosen as the mode of analysis, and a closed form solution is developed for a quasi-three-dimensional advective-diffusion equation defined for a layered aquifer. The layered aquifer is idealized as an aquifer-aquitard system in which the solution domain is considered to be finite and two dimensional in the aquifer region and infinite and one dimensional in the adjacent aquitards. The analytical solution outlined emphasizes the advection of contaminant in the longitudinal direction in the aquifer and also in the transverse vertical direction in the aquifer-aquitard system. The analytical solution also includes the two-dimensional diffusion of the contaminant in the aquifer, one-dimensional diffusion in the aquitards, and first-order reaction and retardation terms in both aquifer and aquitards.