Hydrochemistry and quality assessment of groundwater in the Ardabil area, Iran

In the study area, groundwater is the main water resource for various purposes such as drinking, agriculture and industrial. To evaluate the hydrochemical characteristics of groundwater and suitability for drinking, irrigation and industrial purposes, seventy-seven samples were collected and analyzed for various ions. Results show that, groundwater in the study area is mainly hard to very hard, and slightly alkaline-fresh to brackish in nature. According to the hydrochemistry diagrams, the main groundwater types are Ca, Mg-HCO3, Na-HCO3 and Na-Cl. Calculation of mineral saturation index indicate that the groundwater samples are saturated with respect to carbonate minerals and under-saturated with respect to sulfate minerals such as gypsum and anhydride. The mineral weathering, mixing, ion exchange and anthropogenic activity are the dominant hydrogeochemical natural processes. Results of investigating the quality of heavy metals and calculating the heavy metal index indicated that the groundwater of study area is not contaminated with heavy metals. In this research, the various indices were used to determine the quality of groundwater for various uses. Calculate the indices and comparison results with the WHO standards to determine the quality of groundwater for various uses indicated that the most of the groundwater in study area is chemically suitable for drinking, industrial and agricultural uses. © 2016, The Author(s).