Introduction Hazaribagh is a densely populated area of Dhaka city where the main leather-tanning zone of Bangladesh is situated. About 185 tanneries have been operating their activities on an area of 4 km 2 , processing 220 metric tons of hide a day and about 40–50 l of liquid for each kilo of hide (United Nations Industrial Development Organi- zation 2000). The industries of the 55-year-old tannery complex are discharging their solid wastes and liquid effluent containing putrid rotten flesh, fat, blood and skin, toxic chemicals, dissolved lime, chromium sulfate, alkali, hydrogen sulfide, sulfuric acid, bleach, dyes, oil, formic acid, heavy metals, suspended solids, organic matters, etc., directly into low-lying areas and water bodies between the flood protection embankment and residential area without proper treatment. There is, therefore, an obvious risk of percolation of leachate from the open dumping site which may affect the sedi- ment and groundwater as well as the surface water of the rivers Buriganga and Turag. The uncontrolled dumping of huge industrial wastes of point and non-point sources Anwar Zahid K.-D. Balke M. Qumrul Hassan Matthias Flegr Evaluation of aquifer environment under Hazaribagh leather processing zone of Dhaka city Received: 26 September 2005 Accepted: 15 February 2006 Published online: 14 March 2006 Ó Springer-Verlag 2006 Abstract Hazaribagh is a densely populated area of Dhaka city where about 185 leather processing indus- tries have been operating and dis- charging solid and liquid wastes directly to the low-lying areas, river and natural canals without proper treatment. The area is covered by alluvial deposits of Holocene age and is underlain by Pleistocene Madhupur clay. The Dupi Tila Formation of Mio-Pliocene age underlain by this yellowish gray to brick red clay bed serves as the main water-bearing aquifer of Dhaka city. To assess the environmental degra- dation as well as the groundwater environment, major anions, cations and heavy metals of water samples, heavy metals and organic carbon content of sediment samples were analyzed in this study. Analyses of tannery effluent detect high concen- tration of Na + , Mg 2+ , Cl ) and SO 4 2) followed by Ca 2+ , NH 4 + and K + with remarkable contents of some trace elements, mainly Cr, Fe, Mn, S, Ni and Pb. Higher accumu- lations of Cr, Al and Fe are observed in topsoil samples with significant amounts of Mn, Zn, Ni and Cu. Concentrations of ions and all the investigated trace elements of sam- pled groundwater were within the maximum allowable limit for drink- ing water of the Department of Environment, Bangladesh (DoE), and World Health Organization (WHO). However, excessive con- centrations of Cr, Pb, etc., have al- ready been reported in the shallow groundwater (10–20 m) of the area. Due to excessive withdrawal the vulnerability of groundwater con- tamination in deeper parts cannot be avoided for the future. Keywords Tannery Æ Solid waste Æ Effluent Æ Groundwater Æ Chromium Æ Bangladesh Environ Geol (2006) 50: 495–504 DOI 10.1007/s00254-006-0225-1 ORIGINAL ARTICLE A. Zahid (&) Ground Water Hydrology, Bangladesh Water Development Board, 72, Green Road, 1205 Dhaka, Bangladesh E-mail: anwarzahidb@yahoo.com Tel.: +880-2-7287176 Fax: +880-2-8121272 K.-D. Balke Æ M. Flegr Institute for Geology and Paleontology, University of Tuebingen, Tuebingen, Germany M. Q. Hassan Department of Geology, University of Dhaka, Dhaka, Bangladesh