Assessing the performance of a permeable reactive barrier–aquifer system using a dual-domain solute transport model

Abstract

Transport behavior through a permeable reactive barrier (PRB)-aquifer system is complicated because of the different physical and chemical properties of the PRB and the aquifer. Dual-domain solute transport models are efficient tools for better understanding the various processes and mechanisms of reactive solute transport through a PRB–aquifer system. This study develops a dual-domain analytical model to assess the physical and chemical processes of two-dimensional reactive solute transport through a PRB–aquifer system. The dispersion processes of a dual–domain system on the solute transport are investigated. The results show that the dispersion parameters in a dual-domain system synchronously govern the dynamic shape of the contaminant plume. The low longitudinal and transverse dispersion coefficients of a dual-domain system may restrict the spreading of the plume and elevate the plume’s concentration level. The derived analytical solution is applied to explore how the different reactive transport processes affect the performance of a PRB-aquifer system. The results show that the first-order decay rate constant of the PRB has a critical effect on the performance of the PRB-aquifer system, whereas the effects of the physical dispersion properties on PRB performance are less significant.