Detection and characterization of a vinyl chloride plume inside an urbanized area

The paper deals with an alluvial origin sandy confined aquifer contaminated by vinyl chloride and located in the Padana plain immediately to the south of the Po river and 5 km to the north of the city of Ferrara (northern Italy). Plume investigation followed three steps with a progressive downscaling: 1) a regional hydrogeological characterization; 2) a hydrochemical survey of existing 37 long-filtered boreholes with a gross definition of the plume; 3) a 17 direct-push drillings based characterization.. The investigation identified, inside a mainly urbanized area, a plume with a length 1.7 km and a maximum width of 0.3 km with VC concentration up to more than 11000 ppb and practical absence of other chlorinated ethanes and ethenes and ethylene. To optimise VC analysis it has been verified the coupled use of a inertial pump for collecting the sample preceded by a short term low flow purging by peristaltic pump.