Electrochemical Remediation of Contaminated Groundwater: Pilot Scale Study

Electrochemical technologies for groundwater treatment use a low-level direct current (DC) through electrodes in wells, which enables manipulation of groundwater chemistry. There are several advantages to this approach: 1) It is sustainable and can be driven by a renewable energy source (e.g., solar power), 2) it does not require the addition of solutions or chemicals into groundwater, and 3) the rates of redox reactions can be controlled by adjusting electric current intensity. Two transformation mechanisms are evaluated within this approach depending on electrode materials used: electrochemical reduction of contaminants using iron anodes and foam cathodes, and electrochemical oxidation of contaminants by generation of reactive oxygen species (ROS) using inert electrodes. The first step in implementation of electrochemical technologies is the development of an electrolytic reactor within the aquifer. The effects of the concentration of added ferrous ions, salts, and operational conditions such as flow rates and current density have been considered to optimize the remedial system conditions.