The construction of a thermoelectrical power plant in a coastal area in Southern Italy required a significant lowering of the water table of the underlying unconfined aquifer. A large increase in the salinity of the groundwater was therefore expected. Because of the presence of farmland in the area, a detailed investigation was required to predict the effects of this extensive pumping on the saltwater intrusion. A numerical study was therefore conducted on the area using a 3D, fully coupled finite element model. This paper summarizes the results obtained in the study. The simulation proceeded initially with the determination of the actual steady state profile of the saltwater intrusion under unperturbed conditions. Then, modifications to concentration profiles due to water pumping were determined under different scenarios. The results obtained agree well with the limited field data that are available up to date.