The comparison of the results confirms that there are differences in the electroremediation between the two tailings, even if the pH is similar and a mineralogical analysis showed similarities between the samples with respect to composition. It was found that an electroremediation is more favorable on the old tailings. The results showed that the best experimental conditions for both tailings is a pretreatment with H(2)SO(4)1 M followed by applying 40 V for 7 days, using ion exchange membranes. In this case 16.7% of copper was removed from the anode section for the old tailings, whereas only 11.2% was removed from the new tailings. The current efficiencies with respect to copper for the old and new tailings were 1.7% and 1.6%, respectively. (C) 2012 Elsevier Ltd. All rights reserved.