Hydrochemistry of Groundwater in Dibdibba Aquifer Between Karbala and Najaf, Centeral Iraq

Abstract

Thirty-seven water samples were collected from the study area between Karbala and Najaf under longitudes (43°90´-44°25´) and latitudes (31°95´-32°40´) to study the physicochemical properties including concentrations of the major ions, minor ions, and heavy metals. The electrical conductivity ranged between (2670-13270 µ/cm), total dissolved solids (1709-8489 ppm), calcium (188-798 ppm), magnesium (81-563 ppm), potassium (3-128 ppm), sodium (235-1200 ppm), chloride (355-1710 ppm), sulphate (582-2740 ppm), bicarbonate (114-1358 ppm), nitrates (0.2-2.1 ppm), the concentration of iron, lead, and cobalt were less than (0.05 ppm), manganese (0.05-0.23 ppm), copper (0.143-0.157 ppm), and nickel (0-0.21 ppm). The hydro-chemical variables showed that salinity concentrations and the major ions increase in the direction of groundwater flow. The water type in the study area is sulphate; The groundwater is polluted with heavy metals in some places in the study area, as it was higher than the permissible standard limits, especially for (Mn, Ni, pb). As for the evaluation of groundwater in the study area for human drinking purposes, it was found that it is not suitable in most of the wells. With regard to its use for animals, it is suitable for livestock and unsuitable for poultry. Indicators (SAR, Na%, PI, KI) were used to evaluate water for irrigation purposes and it was found to be good.