Methodological study on pesticides in Alsatian groundwater

The risk assessment conducted by many federal and state agencies have generally relied on deterministic approaches, that use single input/output values, generally selected to fulfill the goal of being health protective. But, the presence of uncertainty and variability within the parameters of the procedure of risk assessment let them assume different values within a range of possible values, each with different probability of occurrence. In particular, the case study deals with groundwater contamination by agrochemical substances occurring in the French aquifer of Alsace. The regional supply of drinking water, water for irrigation and industrial water depends mainly on this water resource. A proper management of this area must consider, thus, the sustainability of a landscape capable of multiple uses and the overwhelming presence of censored data. For this reason, particular attention is given to the characterization of the extent and the chemico-physical distribution of the pollutant source for what concern the delimitation of the hazardous areas, to the determination of the probability density functions of the concerned variables and of the representative concentrations.