Abstract: This study provides an evaluation of the utility and resolution of geoelectrical method in mapping contaminant distribution in the subsurface, and provides a window into the processes that may control their response at a site in south Italy. In situ and 2D and 3D surface resistivity tomography, were used to investigate the electrical properties of a light nonaqueous phase liquid hydrocarbon contaminant plume that resulted from about 10 years of leakage into a karstic environment setting. Overall, the electrical signature from the in situ resistivity measurements were best able to image the subsurface stratigraphy and the associated contamination zone.
Throughout this investigation, geoelectrical measurements consistently recorded high resistivities associated with zones containing the free residual product plume instead of low resistivities as has been suggested by the simple intuitive model. From this, it is inferred that substantial modification of the geochemical characteristics of the subsurface ground materials, surrounding media, and associated groundwater has occurred as a result of biogeochemical reactions. It is evident from this study that in geoelectrical measurements can characterize the distribution of relatively high resistivity zones that may be associated with the presence of hydrocarbon contaminant in the subsurface. Thus, the application of these techniques to hydrogeologic, contaminant monitoring, and remediation studies are far reaching.

Brief Biography of the Speaker:
After the Degree in Physics he has achieved the title of PhD in Geophysics for the Environment and the Territory. He develops the activity of research at the observatory of Environmental Chemistry, Physics and Geology, Department of Science of Materials - University of the Salento.
He is Assistant professor in the following Archaeological Geophysics, Applied Geophysics, Laboratory of Geophysics, Physics of the Earth, Geophysical data processing, Environmental Geophysics, Seismology at the Faculties of Sciences and Faculties of Cultural Heritage at the University of the Salento.
He collaborates to the summer school of "Geophysical Techniques for the Cultural Heritage", developing lessons on the acquisitions and processing of ground penetrating radar data.
He is Professor at the International Master in Urban and Territorial Diagnostic at the University of Salento Cagliari (Italy), Messina (Italy), Palermo (Italy), Pisa (Italy), Trieste (Italy), Atene (Greece), Barcellona (Spain), Buenos Aires (Argentina).
From 2003 He is in the list of the experts in Environment Physics of the Italian Geophysical Association.
From 2003 He is referee of numerous international journals.
In 2004 He has won the Prize for the Physics received by the Italian Physics Society.
From 2006 He is inserted in the international scientific committee to arrange regulations for Geophysical
Surveys.
From 2007 He is inserted in the scientific committee of the International Union of Geological Sciences of the UNESCO for the evaluation of the sites of historical and environmental interest.
From the a.a. 2007/08 He is Professor of Cartography and Topography at the Faculties of Science and at the University of the Salento.
Currently it is researcher at the Department of Science of the Materials - University of the Salento – on the Environmental Geophysics.
He is author of numerous scientific papers, published on national and international Journals, in the field of the geophysics applied to the hazard and disaster management, archaeology, cultural heritage, environment, engineering and the geology.
The activity of research has been, and is currently, related to the Geophysics Applied to shallow subsurface (GPR, electrical tomography, seismic refraction and reflection, seismic tomography, microgravimetry).