Procedia Earth and Planetary Science 7 (2013) 101 – 104 1878-5220 © 2013 The Authors. Published by Elsevier B.V. Selection and/or peer-review under responsibility of the Organizing and Scientific Committee of WRI 14 – 2013 doi:10.1016/j.proeps.2013.03.156 Water Rock Interaction [WRI 14] Groundwater contamination and water-rock interaction during leakage of industrial waste water into a carbonate aquifer in an arid zone, Israel A. Burg a ,* I. Gavrieli a , a Geological Survey of Israel, 30 Malkhei Israel St., Jerusalem 95501, Israel. Abstract Leakage of contaminated, acidic, and salty waste water from a chemical industrial complex in the Negev desert, Israel, resulted in increased salinity of the water in the regional carbonate aquifer. Changes in concentrations of the major elements and some ionic ratios enabled delineating the mixing process of the waste water in the aquifer. Although the waste water is enriched in trace elements, no noticeable change in their concentrations was detected in the contaminated aquifer. The removal of the trace elements is attributed to adsorption that was enabled by a rise in the pH of the contaminated water as it comes in contact with the carbonate host rock. © 2012 The Authors. Published by Elsevier B.V. Selection and/or peer-review under responsibility of Organizing and Scientific Committee of WRI 14 - 2013 Keywords: contamination, salinization, Judea Group, carbonate aquifer, acidity, trace elements. 1. Introduction Contaminated water from a chemical industrial complex in the northern Negev desert, southern Israel (Fig. 1), was allowed to infiltrate into the subsurface for several decades, until the mid 1990s. The infiltrating water differs significantly from the natural groundwater of the regional aquifer in both the salinity and trace elements content. The interaction between the industrial waste water and the host rock in the unsaturated zone as well as between the rock and the mixed water in the aquifer itself resulted in a sharp change in the composition of the groundwater. Here we describe the changes and processes that occurred over the years in the subsurface that are due mainly to water rock interactions and basic chemical processes. * Corresponding author. Tel.: +972-2-5314294; fax: +972-2-5314332. E-mail address: burg@gsi.gov.il. Available online at www.sciencedirect.com © 2013 The Authors. Published by Elsevier B.V. Selection and/or peer-review under responsibility of the Organizing and Scientific Committee of WRI 14 – 2013 Open access under CC BY-NC-ND license. Open access under CC BY-NC-ND license.