''A highly polluted marine system in Italy: from the conceptual site model to the preliminary remediation strategies.''

The paper deals with an innovative approach to the management of contaminated sites, where geotechnical engineering bridges the gap between site characterisation and addresses for remedial strategies. Such approach has been successfully applied to one of the most critical industrial sites in Europe, which is the marine site of the Mar Piccolo in Taranto (Italy), also declared ‘at high risk of environmental crisis’ by the national government. The high degree of pollution that has been recorded in the clayey sediments at the sea bottom was found to affect the water quality and promote bioaccumulation of pollutants in fishes and mussels. These findings triggered a governmental investigation campaign to define sustainable remediation actions for the environmental risk mitigation. The site characterisation involved experts from geotechnical engineering, geological, sedimentological, mineralogical, hydraulic engineering, hydrological, chemical, geochemical, biological research fields, who cooperated to gather a new insight into the origin, distribution, mobility and fate of the contaminants within the basin and to define an original Conceptual Design Site Model (CDSM). The present contribution highlights some aspects of such holistic approach, from selected results from the multidisciplinary characterisation of the sediments to some addresses on remedial strategies and few considerations about solidification/stabilisation solutions for polluted sediments after dredging.