Groundwater Vulnerability Essay

Fresh water being one of the basic necessities for sustenance of life on the earth, the human race through the ages has striven to locate and develop it. Water, a vital source of life in its natural state is free from pollution but when man tampers the water body it loses its natural conditions (Asadi et. al 2007). Groundwater has been considered as an important source of water supply due to its relatively low susceptibility to pollution in comparison to surface water, and its large storage capacity (US EPA,1985). The occurrence and movement of groundwater in an area is governed by several factors such as topography, lithology, geological structures, depth of weathering, extent of fractures, secondary porosity, slope, drainage pattern, landforms,

and Margat, 1970). The concept of groundwater vulnerability to contamination is based on the assumption that the physical environment may provide some degree of protection to groundwater against natural and human impacts with respect to contaminants in the groundwater (Hallaq and Eliash, 2011). A common definition of groundwater vulnerability has not been agreed upon and various definitions of vulnerability have been proposed (Lindstorm, 2005). One mostly used definition is given by NRC that defined groundwater vulnerability as “the tendency or likelihood for the contaminants to reach a specific location in the groundwater system after release at some location above the uppermost aquifer" (NRC,1993; Thirumalaivasan and Karmegam, 2001). Later on Vrba and Zaporozec (1994) defined groundwater vulnerability as “an intrinsic property of a groundwater system, depending on the sensitivity of that system to human and/or natural impacts”. Foster and Hirata (1988) aquifer pollution vulnerability as the “intrinsic characteristics which determines the sensitivity of various parts of an aquifer to being adversely affected by a imposed contaminant