HR: 1340h
AN: H53A-1218    [Abstracts]
TI: Sustainable Exploitation of the Coastal Aquifer in Israel: Search for Water Quality Stratification in the Saturated Zone
AU: * Raanan, H
EM: raanan@bgumail.bgu.ac.il
AF: Department of Geological and Environmental Sciences, Ben-Gurion University of the Negev, P.O.B. 653, Be'er Sheva, 84105 Israel
AU: Vengosh, A
EM: avnerv@bgumail.bgu.ac.il
AF: Department of Geological and Environmental Sciences, Ben-Gurion University of the Negev, P.O.B. 653, Be'er Sheva, 84105 Israel
AU: Seiler, K P
EM: Seiler@gsf.de
AF: GSF-National Research Center, Ingolstadter Landstrasse 1, Neuherberg, D-85758 Germany
AU: Maloszewski, P
EM: maloszewski@gsf.de
AF: GSF-National Research Center, Ingolstadter Landstrasse 1, Neuherberg, D-85758 Germany
AB: Stratification of water layers in the upper part of the saturated zone in unconfined aquifer has been reconstructed by environmental isotope tracers in combination with traditional hydrogeology, hydrochemistry, and numerical modeling. In particular the relationship between modern recharged and old recharged waters was evaluated. Numerical modelling and field studies conducted in Germany and Venezuela have demonstrate that more than 85 % of the groundwater recharge is turned over in aquifers close to the water table (i.e., active recharge zone) and less than 15 % reaches greater depths (passive recharge zone or deep groundwater). Here we investigate the water quality stratification in the saturated zone of the coastal aquifer of Israel. We use pumping wells with different screen depths to provide access for multiple depth analysis of the aquifer along several cross-sections perpendicular to the coast line. Tritium data of deep wells (top end screen deeper than 80m below sea level) show low values ($<$0.9TU). In contrast, shallow wells (upper than 30m) reveal higher tritium levels ($>$3.0TU). A transition zone was identified at a depth range of 30-80m, showing a wider tritium range (0-4.2TU). Our data reveal water layering of different ages in the upper part of the saturated zone in spite of lack of physical separation by low-conductivity layers.
DE: 1829 Groundwater hydrology
DE: 1831 Groundwater quality
DE: 1832 Groundwater transport
DE: 1884 Water supply
SC: Hydrology [H]
MN: 2004 AGU Fall Meeting