Environmental and health impact of current uranium mining activities in southwestern Sinai, Egypt

Abstract

Stream sediments and groundwater samples were collected from the vicinity of El Allouga uranium mine in southwestern Sinai and analyzed for their radionuclides to explore the geochemical dispersion and environmental impact. The radioactivity measurements were performed using γ-ray spectrometry and UV-photometry. Most stream sediments samples have eU concentrations more than the background level. The significant correlations between eU, clay, and organic matter contents reflect possible adsorption of U to the surface of clay and organic matter. The high radionuclide concentrations in the stream sediment are mainly due to contamination from the mining process, and, in some locations, due to rock outcrops weathering. The measured concentrations of U in groundwater samples exceed the Maximum Contamination Level of groundwater U (30 ppb). The lack of correspondence of U concentrations in the country rocks and associated groundwater indicates the high mobility of U and reflects absence of a simple rock/water equilibration. Water resources in the study area have 234U/238U activity ratios with obvious deviations from secular equilibrium. The U isotopic data support that uranium ore body could be locally forming within the rock aquifer at El Allouga area. The calculated external hazard parameter values are higher than the worldwide average in 30% of the studied stream sediment samples; this indicates that people who are exposed to that level of radiation for a lifetime would have an elevated cancer risk. The Annual Effective Dose resulting from U activity concentrations in the studied drinking water is significantly higher than the recommended limit for children and adults. Therefore, the available water resources in the study area are considered unsafe for human consumption.