Assessment of Contaminant Migration in Groundwater from an Industrial Development Area, Annaba District, NE Algeria

Abstract

The characterization of a hydrologically complex contaminated site bordering the Meboudja river (Annaba, Algeria) was undertaken by investigating surface water and groundwater affected by number of industrial rejections that have been established during 1999–2005 in the El-Hadjar Industrial Development Area, Annaba region, North-East of Algeria. The treated and untreated effluents from the industries are being discharged in Meboudja wadi. Groundwater level and water quality monitoring was carried out from 1999 to 2005 in El-Hadjar and surroundings. Surface water samples were also analyzed for the water quality assessment. The groundwater shows a high electric conductivity (more than 560 μS cm⁻¹ with a maximum exceeding 20,000 μS cm⁻¹), a high chloride content (with a maximum exceeding 6,000 mg L⁻¹), and a high sodium concentration (mean = 420 mg L⁻¹) which are observed for the wells located down gradient and near the industrial rejections. The Meboudja is all along its course acting as a diffuse source of contamination of groundwater. Aquifer parameters were estimated by carrying out pumping tests at a number of wells. Groundwater flow and mass transport models were prepared using visual MODFLOW software. The extent of migration of contaminants from the Meboudja and other streams has been assessed for 6 years (1999–2005). The stream-aquifer interaction was found to be responsible for faster migration of contaminants in the over-exploited area east of the Seybouse River.