Vulnerability of groundwater is a relative, non-measurable, dimensionless property. It is based on the concept that “some land areas are more vulnerable to groundwater contamination than others”. Maps showing groundwater vulnerability are useful in planning, policy and decision-making process concerning groundwater management and protection. They also help with identification of areas more susceptible to contamination than others. Overlaying these maps with maps showing the location of each contamination source or land use enables the creation of risk maps.
The report by Musekiwa and Majola (2011) describes the parameters affecting groundwater vulnerability methods for assessing groundwater vulnerability. The DRASTIC method is used for creating a groundwater vulnerability map for South Africa.
Musekiwa, C., & Majola, K. 2011. Groundwater vulnerability map for South Africa. Council for Geoscience Report Nu,ber: 2011-0063.