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The increase in oil production from petroleum reservoirs has led to studies examining the effects of these activities on groundwater quality. Oily wastewater associated with oil production is often reinjected through abandoned wells into the unproductive portions of the reservoir to avoid its discharge on the surface. The reinjection process is designed to be environmentally friendly and to exclude direct interactions between injected fluids and the surrounding groundwater; nevertheless, the evaluation of the compatibility between this process and the protection of the surrounding environment is of utmost importance when oilfields are located within sensitive and protected areas. The present work aimed to evaluate the impact of the oily wastewater reinjection into a long-term and high-rate disposal well in the Val d’Agri oilfield (Southern Italy). Previous preliminary investigations carried out at the study site led researchers to hypothesize the possible hydrocarbon contamination of the shallower aquifer caused by reinjection well integrity issues. Our strategy is based on an integrated and multidisciplinary approach involving isotopic (stable isotopes 2H and 18O), chemical, and microbiological (characterization of bacterial and archaeal communities) analyses. After a comprehensive and meticulous examination of the research data, it has been ascertained that significant discrepancies exist between the shallow and reinjection water systems. This allowed us to clarify the area’s complex flow dynamics and exclude hydrocarbon contamination of spring waters caused by the reinjection process.

Turbidite successions can behave either as aquitards or aquifers depending on their lithological and hydraulic features. In particular, post-depositional processes can increase rock permeability due to fracture development in the competent layers. Thus, at a local scale, turbidite systems warrant further detailed investigations, aimed at reconstructing reliable hydrogeological models. The objective of this work was to investigate from the hydrogeological perspective a turbiditic aquifer located in southern Italy, where several perennial and seasonal springs were detected. Considering the complex hydrodynamics of these systems at the catchment scale, to reach an optimal characterization, a multidisciplinary approach was adopted. The conceptual framework employed microbial communities as groundwater tracers, together with the physicochemical features and isotopic signature of springs and streams from water samples. Meanwhile, geophysical investigations coupled with the geological survey provided the contextualization of the hydrogeological data into the detailed geological reconstruction of the study area. This modus operandi allowed us to typify several differences among the samples, allowing identification of sources and paths of surface water and groundwater, along with diffuse groundwater outflow along streams. As a final result, a hydrogeological conceptual model was reconstructed, underlining how at a very local scale the lithologic, hydraulic, and geomorphological heterogeneity of the studied relief can lead to an improved hydrogeological conceptual model compared to that of other turbidite systems. These results open new questions about the hydrogeological behavior of turbiditic aquifers, which could be pivotal in future research. In fact, these systems could support relevant ecosystems and anthropic activities, especially where climate change will force the research of new (and probably less hydrogeologically efficient) water sources.

Establishing the natural background levels of chemical elements is very often extremely complicated. This is even more true especially for the more anthropized areas, where the concentration of an element in the environmental matrices is conditioned not only by the natural (geogenic) context but also by anthropic activities. In this study, the natural background levels (NBLs) of several chemical elements in the stream sediments of the High Agri River basin have been calculated using a combination of multivariate statistical analysis (MSA) and machine learning techniques in the frame of compositional data analysis (CoDA). Specifically, data clustering and robust principal component analysis (rPCA) have allowed us to recognize and isolate three different data populations, belonging to three different geological domains. A first population of data is clearly related to calcareous lithologies, while the second one is associated to siliciclastic lithologies. A third one is of mixed origin, partly linked to the volcanoclastic nature of the sediments and due to the presence of co-precipitation phenomena. The three data populations have been later separated into three different databases and, whereas needed, the outliers have been eliminated. Based on the obtained results, the NBLs have been calculated using the US-EPA's (United States Environmental Protection Agency) ProUCL software. The results derived from this new approach have been later compared with those obtained using the spectral analysis (S-A) method to evaluate its advantages and versatility. This approach allowed calculating more reliable natural background values.

Ground penetrating radar (GPR) and electrical resistivity tomography (ERT) are typical geophysical techniques applied into archaeological context thanks to their capability to study variations of physical attributes of buried objects in the soil causing electric and electromagnetic contrasts compared to the behaviour of the surrounding environment. Unfortunately sometimes these contrasts are difficult to define for several reasons including strong attenuation of signals introduced into the soil, limited depth and low resolution of investigation related to instrumentation characteristics. Great efforts are required to understand the complexity of the relationship between archaeological features and their geophysical response and give an effective interpretation of resulting data. For this reason an experimental activity has been performed at the Hydrogeosite laboratory focused on the assessment of the capability of geophysical techniques to detect archaeological remains placed in humid or saturated subsoil.