Electroremediation in low-hydraulic conductivity zones – current stage of knowledge and small-scale laboratory experiment

Abstract

Over past decades, the rapid increase of industrial activities has caused vast environmental pollution by different types of contaminants. Groundwater sources belong to the most vulnerable parts of the environment. Zones, especially aquifers with low hydraulic-conductivity (mainly clayey, silty soils with gravels) represent a considerable challenge for scientists to remediate due to their low transmissivity values. Conventional remediation methods (i.e. pump and treat) are ineffective in such conditions; therefore, new and effective methods are required. Electroremediation appears to be a suitable technique in aquifers with low-hydraulic conductivity. Although, this method has been known for decades, there is still a lack of field applications. This article summarizes the current stage of knowledge in electrokinetic remediation of contaminants (e.g. hydrocarbons, metals) in low-hydraulic conductivity aquifers and presents information from certain available field application studies. The aim was to focus on optimizing and enhancing approaches in the electroremediation method and summarily bring useful information to future researchers in their practical utilization. Furthermore, a small-scale laboratory experiment was conducted to prove the efficiency of electroremediation of chlorinated hydrocarbons in groundwater from the model locality (environmental burden), intended for large-scale pilot decontamination by this approach.