Assessment of groundwater vulnerability to nitrate contamination in the surficial aquifer of the rio Cixerri Plain (south Sardinia, Italy)

Abstract

Results of groundwater monitoring in the Rio Cixerri plain, envisaged by Sardinia’s Water Protection Plan, revealed high nitrate content. The presence of nitrates in groundwater bodies can be attributed chiefly to the use of mineral and organic fertilizers, municipal and industrial wastewater discharges, sewer leakage and cesspit sewage disposal.In order to assess the potential risk for groundwater contamination we used the SINTACS method for evaluating intrinsic vulnerability, supplemented with the hazard zones analysis and hazard index for agricultural nitrate groundwater contamination (Italian acronym IPNOA). In this way it was possible to assess the specific risk of nitrate contamination. To create the information layers envisaged by these methods, the gathered data were entered into a database and handled in a GIS environment for best representing the nitrate contamination scenario.