Geochemical Study of Chemical Pollution and Quality of Groundwater of the Terminal Complex, in Ouargla, South-East of Algeria

Abstract

Abstract

Human health can be negatively impacted by low-quality or contaminated drinking water. Investigating groundwater quality and appropriateness for irrigation and drinking uses is therefore crucial. This study uses the entropy theory and geochemical characteristics to describe the groundwater quality in Algeria's Ouargla area. From the study region, a total of 28 samples have been gathered. The results show that the study area is characterized as being within an arid region where rainfall was lower; hence, the evaporation process becomes dominant in controlling the groundwater chemistry. and 75.72% of groundwater samples are active in ion exchange processes, with 14.28% having negative values, indicating reverse ion exchange of Na+ and K+ ions. The entropy-weighted water quality index (EWQI) calculation for groundwater samples revealed a range of water quality, from medium to extremely severe. Of the groundwater samples obtained, 46.7% were identified as medium, 40% as poor, and 13.3% as extremely poor. Based on Sodium hazard (SAR) 3.57% 46.42%, 17.85% and 35.71% of the samples were found to be in the Excellent, Good, Poor, Unsuitable respectively and according to Kelly’s ratio (KR) 96.43% of the samples were found in suitable category. Permeability Index (PI) indicates that 92.86% of the groundwater samples were found suitable and 7.14% unsuitable category for irrigation purpose.