An analytical solution of two-dimensional reactive solute transport in an aquifer-aquitard system

This article presents an analytical study of twodimensional reactive solute transport in an aquiferaquitard system. Advection, longitudinal and vertical dispersion, firstorder irreversible decay, and linear sorption are included for aquifer transport. Advection, vertical diffusion, firstorder irreversible decay, and linear sorption are considered for aquitard transport. This study solves transport equations in the aquifer and aquitards simultaneously and maintains continuities of concentration and mass flux at the aquiferaquitard interfaces. The transport equations are first solved in Laplace domain, and the solutions are then inverted numerically to yield solutions in the real time domain (the Zhan solution). Concentration profiles in the aquifer and the aquitards are obtained and mass transported to the aquitards is also calculated. Closedform steady state solutions of concentration and mass have been obtained. The Zhan solution is compared with solutions derived with the averaged volumetric sink/source approach (the AA solution). The AA solution substantially overestimates the concentration and the mass in the upper aquitard when an upward velocity exists in the aquitard. The penetrating depths of the solute in the aquitard are similar for the AA solution and the Zhan solution.

An analytical solution of two-dimensional reactive solute transport in an aquifer-aquitard system Academic Article