Modelling surfactant-enhanced remediation of polycyclic aromatic hydrocarbons

Within the framework of a comprehensive investigation concerning the use of surfactants to enhance the in situ remediation of polycyclic aromatic hydrocarbons (PAH) contaminations in the subsurface, SMART (Streamtube Model for Advective and Reactive Transport), a multicomponent transport model, was developed to study the processes (interactions) taking place when surfactants and PAH migrate through porous media as solutes. The model is an adaption of a Lagrangian method allowing for separate treatment of conservative transport and reactive processes. It accounts for the hydraulic as well as physico-chemical heterogeneity of porous aquifers. The system of processes implemented in the model has been shown to be able to represent the behaviour of PAH and surfactants in porous media at the laboratory scale. Here the transport model is applied to a simplified two-dimensional remediation scenario (field scale). It is shown how surfactants may influence the clean-up of PAH contaminated aquifers. Emphasis is put on the effect of hydraulic and physico-chemical aquifer properties on the coupled transport of PAH and surfactants.