Determining the groundwater vulnerability using the aquifer vulnerability index (AVI) in the Salatiga groundwater basin in Indonesia

Salatiga Groundwater Basin (SGB) is in the developing area of the Central Java Province/Indonesia which encounters groundwater pollution, and an assessment of the groundwater vulnerability to contamination is needed. This research aimed to define the level of groundwater vulnerability in the SGB. The aquifer vulnerability index (AVI) method was applied, which takes into account two parameters, the thickness of the rock layer, and the hydraulic conductivity. The thickness was then divided by the hydraulic conductivity to calculate the overall hydraulic resistance value. Those values were then interpolated to develop the groundwater vulnerability zone. The results highlight that the SGB has vulnerability zones to contamination that range from very low to very high.