Electrokinetic applications: Site characterization and remediation of soils

This paper summarizes the role of primary and secondary driving forces of pore fluid and contaminant transport in soils during electrokinetic applications. For site characterization, the coupling of pressure gradients (driving force) and electric current (secondary force) are discussed in terms of a 2-dimensional finite difference model for heterogeneous, porous media. The model can be used to determine flow orientation and delineate the spatial flow field. In soil remediation applications, transport is driven by primary electric fields. A computer model of solute transport driven by an applied electrical field was expanded to examine transient behavior of ionic mobilization due to electromigration, chemical diffusion, and fluid convection. An experiment demonstrating the transport of an anionic dye was compared to the model. Although the model appears to predict the transport of the dye, there are concerns that the model may not maintain reasonable electroneutrality throughout the modeled cell