Groundwater Vulnerability Assessment in the Metaponto Coastal Plain (Basilicata, Italy)

Abstract

This study aims at a groundwater vulnerability assessment of the Metaponto coastal plain, located in the Basilicata region (southern Italy). In the last century, intensive agriculture, zootechnical and industrial activities have significantly changed the plain. These changes led to negative impacts on the hydrogeological system intensifying the risk of the aquifer to pollution. The paper presents the assessment of the intrinsic vulnerability of the coastal aquifer carried out by the GIS-based application of the SINTACS method. It considers several aquifer parameters such as water table depth, effective infiltration, unsaturated conditions, soil media, aquifer media, hydraulic conductivity and topography. Furthermore, the anthropogenic influence in the study area was considered by applying the SINTACS-LU method, in which the parameter of land use (LU) was added. The SINTACS and SINTACS-LU vulnerability indexes were provided by summing the product of ratings and weights assigned to each parameter. The analysis of the intrinsic vulnerability map allowed for determining three classes ranging from low to high vulnerability. In both cases, the southeastern part of the coastal plain, closest to the sea, shows the highest vulnerability class, indicating that it is the most vulnerable to contamination due to the hydrogeological intrinsic factors. The wide central part of the study area shows a moderate class of vulnerability and the low class is scattered in small parts in the northern portion of the plain, which represents the areas less contaminable in space and time in the case of potential pollution. In the SINTACS-LU map, some areas classified as highly vulnerable in the SINTACS method show a minor vulnerability class. These areas are localized in natural and wooded sectors of the Metaponto plain, which are less populated, where human impact on the groundwater is minimal.