Hydrogeochemistry and groundwater quality assessment in Nour coastal plain, Mazandaran province, Iran

Groundwater quality in Nour coastal plain in Mazandaran province of Iran is assessed by measuring physicochemical parameters including total dissolved solid, electrical conductivity, pH, total hardness, major cation and anion compositions and Nitrate pollution. For this purpose, fifty groundwater samples were collected in July 2012. The hydrochemical types, Ca–HCO₃ and Mg–HCO₃ dominate in all samples of groundwater. Nearly 98% the groundwater samples fall in the very hard category. Mineral saturation index of groundwater were calculated by PHREEQC. The all groundwater samples are oversaturated with respect to dolomite and calcite. According to Wilcox classification diagram, 98% of groundwater samples classified as C2–S1and C3–S1. In 80% of the groundwater samples sodium hazard was classified as low. In comparison with the WHO’s drinking water guideline of 50 mg l^–1 for NO₃^–, the NO₃^– concentration in groundwater was lower than this limit. The Kruskal–Wallis test is used to compare the NO₃^– parameter between five land uses. The result of Kruskal–Wallis test shows that samples have similar NO₃^– parameter in different land use.