La contaminazione chimica del complesso superficiale di falde nell'area industriale di Porto Marghera, con particolare riferimento alla sua evoluzione nell'ultimo decennio

The chemical contamination of the shallow aquifer complex in the Porto Marghera industrial area. With particular reference to the evolution of the last decade. Abstract: The object of this study is to examine the evolution of the chemical contamination in the industrial area of Porto Marghera. It’s main object is to observe and evaluate the entity of the contamination, it’s permanence and diffusion over time. Only certain chemical contaminants, across the whole analytical spectrum, have been selected and studied from the water samples analysis, gathered from the wells and piezometers in the chosen area. Of particular interest is to observe if and how the contaminants concentration has been influenced by the construction of the diaphragm walls, constructed progressively and still being built. The area of Porto Marghera is an industrial site with a great areal extent, compound by industrial settlements, water channels, ponds and by the commercial port and it’s infrastructures. The industrial activity generated a great impact on the lagoon of Venice and on the mainland, caused by the lack of an environmental legislation aware of the hazardousness of the chemicals used in the industrial processes. The industrial area has been created by the drainage of some lagoon areas, possible thanks to the construction of isles called “macroisole”. These were built using materials available locally and from the excavation of the channels and the wastes of the manufacturing cycles of the first industrial zone. This is the reason for the high contamination of the area since its creation, which allowed the transfer of the pollutants in the industrial canals and then to the lagoon. In 1998 Porto Marghera was identified, via the L.426/1998, as a site for high industrial risk making it become part of Sites of National Interest (called SIN). The definition of the SIN was based on a series of studies formalized with the D.M. Environment of 23/02/2000 in which the area is defined and bounded. The Master Plan for the remediation of polluted sites of Porto Marghera locates inside of the SIN a system of fifteen macroisole. The more suitable areas for the purpose of the study turned out to be the Refineries and Tanks macroisole (Area Petroli), the New Petrochemical macroisola and the Fusina macroisola. This choice, to which was subsequently added the Old Petrochemical macroisola, was made based upon the areal density and the temporal systematicity of the data that could be found. Despite their significant quantities, especially in terms of the number of withdrawals made in individual wells, it was necessary to neglect some areas due to the poor consistency of data relating to one or more analytes that would not permit the trace their evolution.