Analytical Solutions and Simulation Approaches for Double Permeability Aquifers

In this paper we develop analytical solutions for 1D unsteady flow in an infinite double permeability aquifer. Two asymptotic cases are considered: the near-hydraulic-equilibrium-state and the far-hydraulic-equilibrium-state. It is demonstrated that for both cases the equation for the piezometric head can be expressed in leading order, as the classical solution of the simple permeability medium, to which correction terms are added. On the basis of these findings the accuracy of the simulations using conventional approaches (i.e. MODFLOW, MT3D codes) is discussed, while decision tools for the choice of the adequate double continuum model are also provided. Copyright Springer Science+Business Media B.V. 2009