الفهرس 
Chapter 1 Introduction and literature reviewOnly 14 pages are availabe for public view
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Abstract
The potential suitability for selecting a candidate site to host a geologic or (radiological) repository depends in part on investigating the subsurface water systems (unsaturated and saturated zones). So, the susceptibility of these systems to the potential release of radioactive waste from the repository and their migration through the groundwater flow path was calculated over a hundred years to the biosphere.
Site characterization of a proposed area at El Gora city -northeastern part of Sinai Peninsula for installing a nuclear and radiological waste disposal site was studied. The release of radionuclides from a postulated repository was simulated using MODFLOW and MT3DMS numerical models to assess the flow and transport of radionuclides in the groundwater of the Quaternary formation (Alluvial and Kurkar aquifers). The migration of five radionuclides T, 90Sr, 137Cs, 129I, and 99Tc was proposed to be released from the waste disposal site. The transport of these radionuclides was simulated as a function of time, distance, and concentration. The released scenarios were based on two assumptions; continuous leaking of 0.1%; and instantaneous release (100%) from the engineered and geological barrier failure. The results of 0.1% release showed that the activity concentration of the tritium exceeds the permissible limits of drinking water at all distances to 1000m in less time than the institutional control period (100y). Whereas the activities of (129I, 99Tc) are not exceeded the limits and for 90Sr and 137Cs at 100m exceed the limit. In the Kurkar aquifer, the groundwater will be at risk by Tritium till 600m within 21 y. In the case of the total release of the radionuclide concentrations, the groundwater will be at health risk by 90Sr, 137Cs, and 129I contaminants at 100m within 100 y, and by T till 1000m within 30 y. In the lower Kurkar aquifer, the groundwater will be at risk from 90Sr within 60 y at 100m, and by T till 600m within 24 y.