A new electrochemical permeable reactive barrier (Electro-PRB) system for removal of hexavalent chromium [Cr(VI)] using Fe-0 meshes was developed. Electro-PRB was found to be effective for electrochemical depassivation of Fe-0 to remove Cr(VI) during treatment. During initial treatment, Cr(VI) removal rates decreased with time, due to loss of Fe-0 reactivity by mineral fouling. After Fe-0 was passivated, electrochemical depassivation was introduced for different electrolysis times to recover Fe-0 reactivity. It was found that there was approximately 100.4-131.3% initial removal rate recovery, due to the electrochemical break down of precipitates on the Fe-0 surfaces. During the treatment, the decreasing pH and increasing oxidation-reduction Potential (ORP) of the effluent implied the passivation of Fe-0 surfaces. Scanning electron microscope analysis of acid-washed, electrochemically depassivated, and passivated Fe-0 confirmed the efficiency of Elecro-PRB in the recovery Fe-0 reactivity. The results indicate that the Electro-PRB system proposed here is capable of recovering the reactivity of Fe-0, which may prolong the operation of Cr(VI) removal processes. (C) 2012 Elsevier B.V. All rights reserved.