Sanitary landfill has always been the most important system far evacuation of solid waste, being ruled by legislation of numerous Nations. Nevertheless the biodegradation of solid waste which takes place into the soil represents a source of potential pollution which has to be managed very carefully. The exigency or controlling such potential impact on the environment, makes necessary individuation of suitable site for landfill localization and requires evaluation of potential pollution induced by sanitary landfill. Drastic index is based on utilization or 7 hydrogeologic variables which allows to determine the index of risk. In such a way pollution is related exclusively to landfill leachate and its migration trough the groundwater. On the contrary alphanumeric method takes in count a lot or different factors as being essential to risk perception, and try to gives them two values, one related whit entity of damage and the other related whit possibility of happening. Comparative methodology, finally, tends to refer to objectives parameters which are direct1y measurable, so that there is no subjectivity in risk evaluation. For each of the mentioned methods are reported application modalities discussing the different results that can be obtained in case studies.