Environmental Assessment in Wadi AL-Samen Catchment—Hebron/Palestine

Contamination of groundwater poses a significant risk to public health and is, therefore, one of the most serious environmental threats around the world. For Palestinians in the West Bank, groundwater is the most important source for their drinking water, which means that poor water quality may have an impact on their overall health. This research aims at evaluating the environmental impact of wastewater flowing to the groundwater aquifers of the Wadi AL-Samen basin located in Hebron, Palestine. Samples from wastewater as well as springs and groundwater wells were collected during dry and wet seasons of the year 2019 from the Wadi AL-Samen area. Results of wastewater samples showed biological oxygen demand (BOD₅) values up to 250 mg/l as well as high concentrations of chemical oxygen demand (COD) up to 400 mg/l. The results, furthermore, indicate pollution of the wells and springs due to untreated/ insufficiently treated wastewater flowing from the Hebron area and surrounding villages to the Wadi. It was found that the nitrate (NO₃⁻) contents and the concentrations of phosphate (PO₄⁻³) of the springs and wells samples were below the tolerance limits of the World Health Organization (WHO) standards, the WHO allowed concentrations are for BOD₅ less than 5 mg/l, 50 mg/l COD, 50 mg/l NO₃⁻, and 1.0 mg/l PO₄⁻³. Total suspended solid (TSS) values exceeded the limits of 150 mg/l (WHO standard is < 5 mg/l), and in both seasons, the physical parameters, e.g., pH, showed clear evidence of contamination of some springs with wastewater. Regarding the microbial quality for water resources, high concentrations of fecal coliform (FC) and total coliform (TC) bacteria in the springs indicated evidence of pollution with wastewater. The results also showed that the concentration of trace elements, especially cadmium (Cd) and lithium (Li) exceeded the thresholds according to WHO standards, which are 6.5–8.5 for pH, < 1 CFU/ 100 ml FC, < 1 CFU/100 ml TC, 0.05 mg/l Cd, and < 0.2 mg/l Li.