Separation Science and Technology, Vol.44, No.10, 2171-2187, 2009
Electrokinetic Soil Remediation: Challenges and Opportunities
Electrokinetic remediation is effective for extraction of contaminants, such as heavy metals, from fine grained deposits. However, several challenges have led to limited field implementation in the US over the past two decades. The reasons include lower risk of exposure to adsorbed contaminants through groundwater, cost of treatment, technical challenges in difficult soil, and complex geochemical conditions, and the need for acidification to induce desorption. To address practical implementation, a Reactive Transference Factor can be used to identify conditions that are favorable for electrokinetic remediation. The factor measures the reactive transport rates relative to the electrical conductivity of the soil. Other opportunities are identified for implementation of electric-based methods for remediation beyond heavy metal extraction. These include enhancement of bioremediation, which is favorable for remediation of hot spots or source areas, and the development of reactive electrochemical barriers, particularly for the treatment of contaminated groundwater plumes.