Impact of Permeability on Flow and Solute Transport in Highly Heterogeneous Aquifer

The impact of permeability on solute transport process in a highly heterogeneous aquifer was analyzed using the Monte-Carlo method. The logarithm of the permeability (lnK) of aquifer was considered as a non-stationary field with increments being a truncated fractional Lévy motion (fLm) generated using the SRA3DC code. MODFLOW and MT3DMS code were used to solve the flow and solute equations, respectively. Results indicate that larger C lead to a more heterogeneous permeability field. As C increases, solute plumes show more significant anomaly with sharper leading edge and wider tailing edge. The solute plume extends and its second spatial moments increase as C increases, while the first spatial moments of the solute plume are independent of C values. The longitudinal macrodispersivity is scale-dependent and increases as a power law function of time. Increasing C results in an increase in longitudinal macrodispersivity. It was concluded that the nature of transport process is highly dependent on the heterogeneity of the permeability field.