Idrogeologia e monitoraggio delle sorgenti carsiche del Tavo (massiccio carbonatico del Gran Sasso) e loro implicazioni nella gestione dell’emergenza torbidità.

Hydrogeology of the Tavo karstic springs (Gran Sasso carbonate massif, central Italy) and their implication in the management of turbidity emergency ABSTRACT: The study analyses the hydrogeology and the hydrodynamics of the karst systems responsible for the flooding and turbidity of the Tavo springs (central Apennines), consisting of the captated springs of Mortaio d’Angri and Vitella d’Oro. The flow and the chemico-physical parameters of the river and spring waters has been monitored for 14 months, whereas the hourly data concerning flow and turbidity has been analysed from 1978 to 2003. The two captations, fed by a single aquifer, also receive the contribution of a series of karst systems, responsible for the flooding that follows heavy rain. The most intense turbidity occurs at the Vitella d’Oro spring at the beginning of autumn, when the first flood cleans up the karst systems in which the clayey sediments accumulate. If the Vitella d’Oro captation tunnel is continued until it meets the limestone the problem of turbidity could be solved or lessened, however running the risk of depleting the Mortaio d’Angri springs located at higher levels. Key terms: karstic springs, floods, turbidity, karst siphons, Apennines, Italy