Quality of groundwater in the Yarmouk basin, Jordan has been assessed through the study of hydrogeochemical characteristics and the water chemistry as it is considered the main source for drinking and agriculture activities in the region. The results of the relationship between Ca2+ + Mg2+ versus HCO3- + CO32-, Ca2+ + Mg2+ versus total cations, Na+ + K+ versus total cations, Cl- + SO42- versus Na+ + K+, Na+ versus Cl-, Na+ versus HCO3- + CO32-, Na+ versus Ca2+, and Na+: Cl- versus EC describe the mineral dissolution mechanism through the strong relationship between water with rocks in alkaline conditions with the release of Ca2+, Mg2+, Na+, K+, HCO3-, CO32-, SO42-, and F- ions in the groundwater for enrichment. Furthermore, evaporation processes, groundwater depletion, and ion exchange contribute to the increased concentration of Na+ and Cl- ions in groundwater. Anthropogenic sources are one of the main reasons for contamination of groundwater in the study area and for increasing the concentration of Mg2+, Na+, Cl-, SO42-, and NO3- ions. Results show the quality of groundwater in the study area is categorized as follows: HCO3- + CO32- > Cl- > SO42- > NO3- > F- and Na+ > Ca2+ > Mg2+ > K+. In conclusion, the results of TDS, TH, and chemical composition showed that 26% of the groundwater samples were unsuitable for drinking. About 28% of groundwater samples in the study area have a high concentration of Mg2+, Na+, and NO3- above the acceptable limit. Also, based on high SAR, 10% of the groundwater samples were not suitable for irrigation purposes.
Keywords: Geochemical modeling; Groundwater quality; Hydrogeochemistry; Jordan; Pollution; Yarmouk basin.