Fuzzy logic and sensitivity analysis for the classification of groundwater pollution risk

The work described in the present article aims at supplying an environmental planning tool able to define a groundwater risk hierarchy index in function of some intrinsic characteristics of uncontrolled landfills and the territory where they are located. The risk assessment was carried out with a conceptual model, which includes the groundwater vulnerability and the intrinsic hazard of landfills. In particular, in order to define the hazard of landfills, the fuzzy logic theory has been applied. The fuzzy approach has been then combined with the sensitivity analysis in order to overcome the problem of uncertainty associated with both the input data and the implemented fuzzy model, and at the same time to reduce the subjectivity. The assessment of groundwater vulnerability has been carried out with the GNDCI-CNR method. This method, which does not need numerical input parameters, is particularly suitable for a large territory characterized by many geological, hydro-geological and morphological features, in which data and information are often unavailable, generic and territorially inhomogeneous