A semi-analytical model for the simulation of solute transport in a network of fractures having random orientations

A semi-analytical model is developed which accounts for solute transport th rough a multi-dimensional network of fractures having random orientations a nd sparse distribution. Transport processes including hydrodynamic dispersi on, matrix diffusion, retardation, decay and solute transfer at fracture in tersections, are considered. The model is derived by application of the Lap lace transform to the governing transport equation for each fracture elemen t. The resulting ordinary differential equations are linked using robust de scriptions of mass conservation at the fracture intersections. Solute conce ntrations are determined by numerically inverting the transformed equations in a sequential fashion. The model is verified using a formal mass balance and through comparison to existing solutions for solute transport in fract ured media. To illustrate the use of the model, solute transport in a hypot hetical network domain was simulated based on fracture conditions measured at a real field setting in a granitic rock. Copyright (C) 1999 John Wiley & Sons, Ltd.