1 23 Environmental Earth Sciences ISSN 1866-6280 Volume 66 Number 3 Environ Earth Sci (2012) 66:763-772 DOI 10.1007/s12665-011-1284-5 Case study: a 3D resistivity and induced polarization imaging from downstream a waste disposal site in Brazil Andréa Teixeira Ustra, Vagner Roberto Elis, Giulliana Mondelli, Lázaro Valentin Zuquette & Heraldo Luiz Giacheti