الفهرس 
CHAPTER 1: INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Deep excavation activities commonly require groundwater dewatering to lower the water table and allow construction to proceed in dry conditions. Dewatering is a process of lowering the groundwater table by pumping water from the aquifer. This process is commonly used during construction activities to improve soil stability. However, dewatering can also alter groundwater flow patterns and facilitate the transport of contaminants. The effects of various parameters affecting contaminations transport due to dewatering were explored including well depth, contamination depth, horizontal distance between the pollution source and the dewatering well, and the dewatering well discharge. The effects of the aforementioned parameters on contaminations spread, arrival time to the dewatering well area, and final concentration at the dewatering well were discussed in the results. This study discusses the relationship between dewatering and contaminations spreading in groundwater using a numerical model. The numerical modelling (MODFLOW) was performed using 3D finite difference technique. The results considered an arrival time of 2% concentration in the dewatering well area. The results indicate that an increase in pumping well depth led to an increase in arrival time, and the increase in contamination source depth also increased arrival time. Contamination arrived faster with the decrease in horizontal distance and the dewatering well discharge had a noticeable effect on contaminations spread. Careful consideration of the factors listed above is essential for mitigating the potential risks of contaminations transport and protecting groundwater resources.