Water Quality and Radionuclides Content Assessment of the Al-Najaf Sea: Case Study

Abstract

The Al-Najaf state is witnessing an increased economic development and attracting more investments that require the development of new areas and exploring new water resources. This study evaluates the quality of 12 surface water samples and groundwater from 12 wells for irrigation according to the salinity and sodicity hazards based on electrical conductivity (EC) and sodium adsorption ratio (SAR). In addition, the concentrations of radionuclides, which include Thorium (232Th), Uranium (238U), Potassium (40K) and Cesium (137Cs) were tested in four soil samples in the study area. It was found that the average values of pH, total hardness, Na, Ca, Mg, K, Cl, SO4, NO3 for groundwater and surface water were 8 and 6, 2287 and 4006 mg/L, 1140 and 1232 mg/L, 378 and 637 mg/L, 327 and 587 mg/L, 2 and 2 mg/L, 989 and 2007 mg/L, 1149 and 1325 mg/L, as well as 2 and 2 mg/L, respectively. From salinity and sodicity hazards analysis, the groundwater had EC of 5242 μS/cm and SAR of 61, whereas surface water had EC of 6253 μS/cm and SAR of 50. Furthermore, the concentrations of radionuclides, i.e. 232Th, 238U, 40K and 137Cs in the soil samples were found to be 11.02, 34.12, 544.45, and 1.6 Bq/kg, respectively. The concentrations of radionuclides were within the worldwide baseline, expect for 40K. The study concluded that both water sources are classified as very high salinity and sodium water (class C4-S4), and it cannot be used for irrigation, only suitable for the salt tolerant crops.