The relationship between groundwater and surface water in the area north west of Sinai were studied based on major ion chemistry and stable isotopes. The physico-chemical characteristics of the groundwater in the study area indicate that different hydrochemical conditions exist defining geochemical zones with distinct groundwater types. Groundwater samples in the area were classified according to its origin as 78% meteoric and 22% marine, the majority of groundwater samples belong to the more advanced grade of meta-somatic sequence (Cl- > SO4-- > HCO3-). The least mineralized water is found close to El-Salam canal, which is considered as the main recharging source, and the salinity of groundwater increases significantly with distance away from the canal.
Geochemical reaction models have been constructed using major anions and cations and stable isotopes data concentrations observed in the groundwater and surface water samples. These data were processed along flow path to assess the hydrogeochemical processes and calculate the mixing ratios with the different surface water sources. Halite, Calcite, Montmorillonite, Cation exchange, Gypsum, Biotite, Dolomite and Alunite minerals were included as phases in NETPATH model due to the aeolian deposits (sand dune and sand sheets) and alluvial plain deposits (sand mixed with silt and dark clay) that cover most parts of the study area. Mixing phenomena reflected the impact of El-Salam canal as well as sea water on the groundwater quality in the study area.