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In order to assess the potential risk of aquifer pollution in an alluvial plain area used as a landfill, a detailed geological and hydraulic model of the subsoil was realised. The chosen area is represented by the transfer site for solid urban waste called "Maruzzella", in the lower plain of the Volturno River. The analysis of lithostratigraphic data allowed a 3D reconstruction of the subsoil, which was subsequently implemented thanks to a hydrostratigraphic characterization. Through the use of GIS, the calculation grids necessary for the characterization of the flows have been built, elaborated through the use of ModFlowwiththreedifferent 3D models of the subsoil with increasing degrees of geological simplification. The dispersion models created with ModFlow made possible to establish the dispersive dynamics that predominate or coexist in relation to permeability and temporal progression considering different stress periods, respectively equal to 3650 days and 7300 days. The comparison of the geological scenarios highlighted the real dispersive processes, thus underlining the importance of a detailed knowledge of the stratigraphic architecture of the subsoil.

Trace element (TE) pollution in groundwater resources is one of the major concerns in both developing and developed countries as it can directly affect human health. Arsenic (As), Barium (Ba), and Rubidium (Rb) can be considered as TEs naturally present in groundwater due to water-rock interactions in Campania Plain (CP) aquifers, in South Italy. Their concentration could be predicted via some readily available input variables using an algorithm like the iterative classifier optimizer (ICO) for regression, and novel hybrid algorithms with additive regression (AR-ICO), attribute selected classifier (ASC-ICO) and bagging (BA-ICO). In this regard, 244 groundwater samples were collected from water wells within the CP and analyzed with respect to the electrical conductivity, pH, major ions and selected TEs. To develop the models, the available dataset was divided randomly into two subsets for model training (70% of the dataset) and evaluation (30% of the dataset), respectively. Based on the correlation coefficient (r), different input variables combinations were constructed to find the most effective one. Each model's performance was evaluated using common statistical and visual metrics. Results indicated that the prediction of As and Ba concentrations strongly depends on HCO3-, while Na+ is the most effective variable on Rb prediction. Also, the findings showed that the most powerful predictive models were those that used all the available input variables. According to models' performance evaluation metrics, the hybrid ASC-ICO outperformed other hybrid (BA- and AR-ICO) and standalone (ICO) algorithms to predict As and Ba concentrations, while both hybrid ASC- and BA-ICO models had higher accuracy and lower error than other algorithms for Rb prediction.

A significant rise of groundwater pollution has been registered worldwide, where nitrate has been recognized as the most widespread pollutant. In this context, the groundwater vulnerability assessment and more specifically the delineation of &ldquo, Nitrate Vulnerable Zones&rdquo, represents a reliable cost-effective tool for groundwater management. In this study, the Agricultural Nitrate Hazard Index (ANHI) method was applied to two case histories in southern Italy: the Lete River catchment and the eastern sector of the Campania Plain. The first area is characterized by agricultural activities and a low anthropic influence while the eastern part of the Campania Plain, around Caserta city, is strongly urbanized and developed on an extensive alluvial plain filled with volcaniclastic deposits. The parametric method applied suggests moderate hazard for the more natural setting highlighting how the intensive crop farming and livestock activities that characterized the area negatively influenced the results. For the eastern part of the Campania Plain, where a strong urbanization and widespread industrial crops are dominant, a low to very low hazard has been identified. The groundwater quality value, in contrast with the methodology results underlines the importance of further risk evaluations based on accurate aquifer characterization. A multiple year assessment based on land use change and climate variation could further highlights the difference between the study areas.

The Quaternary evolution of the main coastal basins located along the southwestern margin of the Southern Apennines has been reconstructed by integrating the huge amount of existing stratigraphical and geomorphological data. The information produced in the last twenty years has shed new light on the recent (late Middle Pleistocene to Present) history of the Campanian and Sele plains or basins. During the early Quaternary, the analysed coastal basins originated as half-grabens in response to opening processes active since the late Tortonian in the southern Tyrrhenian back-arc basin. In some of these basins (e.g. the Campanian Plain), volcanism has also played an important role. In the inner sectors of the coastal basins, the complex interplay between block faulting, sedimentary inputs and glacioeustatic fluctuations gave rise to relative sea-level change and related coastline migrations, leading to the formation of the present-day coastal plains. In the Sele Plain basin, the construction of the present-day landscape mainly resulted from the substantial ceasing of subsidence in the final part of the Middle Pleistocene. Conversely, a strong contribution to the recent evolution of the Campanian Plain has been provided by abundant volcaniclastic aggradation, able to hinder the effect of the vertical motions that occurred in the last 100 ka.

This study attempts to assess the aquifer vulnerability in the northeastern sector of the Campania Plain (southern Italy). The area is a highly populated region with anthropic impacts caused by rapid urban growth, quarrying, agricultural and industrial activities and uncontrolled waste storage. The main geologic feature of this plain is the alternation of alluvial/transitional and volcaniclastic deposits of Late Pleistocene-Holocene age. The study was performed integrating different sets of geologic and environmental data to restore the stratigraphic architecture and to assess anthropic impacts on subsoil. The reconstruction of stratigraphic subsurface architecture was based on remarkable geodatabase, concerning well log stratigraphies. Specific insights have been delineated on the volcaniclastic lithofacies heteropies across the entire area of study to highlight the differences in lithification degree and permeability. The contribution of pedogenesis on the reconstruction of the stratigraphic setting was also considered for the relative implications on groundwater quality concerns, as paleosols are usually regarded as aquitards. All of this information has been managed into a GIS project to produce a detailed 3D geological reconstruction, integrated with hydrogeological information to provide a model of the aquifer under study, highlighting sites of greater vulnerability to pollution. The anthropic impacts on subsoil were assessed by evaluating land-uses and overlaying the ANHI (Agricultural Nitrate Hazard Index) Map. The integration of the above datasets has allowed to check the reliability of the previsional empirical model with respect to the hydrostratigraphic model based on a thorough stratigraphic model and to verify the real potential of contamination. © 2013 Springer-Verlag Berlin Heidelberg.

The Campania Plain - a broad, complex graben closely controlled by NE-SW, NW-SE and E-W normal fault activity, established in Late Pliocene (IPPOLITO et alii, 1973) or the Early Pleistocene (CINQUE et alii, 1987; 2000) along the Tyrrhenian side of the Apennine Mountains - has been the object of several important studies of its geological setting characterized by the interplay between volcanism, tectonics and sedimentation (IPPOLITO et alii, 1973; ORTOLANI & APRILE, 1985; BRANCACCIO et alii, 1995; ROMANO et alii, 1994; APRILE et alii, 2004). This investigation focuses on the geological characteristics of the Caserta town area and, through the analysis of data from subsurface and field surveys, it aims at defining more precise stratigraphic constraints on the northeastern region of the Plain.Geological data derive from the study of some 300 lithostratigraphic logs from boreholes reaching a 60 m maximum depth. Deeper lithological data (to a maximum 400 m depth) were obtained from boreholes drilled for hydrogeological surveys. Some additional subsurface information was obtained from well samples and from quarries. The key to correlation of the different units is the Campanian Grey Tuff (TGC in the present paper) (~39 Ky B.P. DE VIVO et alii, 2001) and Durazzano Ignimbrite (116 Ky B.P., ROLANDI et alii, 2003) the stratigraphic marker beds in the investigated area. The reconstructed stratigraphic sequence ranges from Middle-Late Pleistocene to Recent. Above the faulted Apennine carbonate bedrock, five units have been defined: two are of marine-transitional facies (M1 and M2) and have been recognized exclusively in the subsurface; the other three units (V1, TGC, TGN) consist mainly of pyroclastic deposits. The Middle to Upper Pleistocene marine-transitional formation (Ml) is at the bottom of the succession. The unit is overlain by mostly incoherent volcanic deposits (V1), which are correlatable with the Durazzano Ignimbrite (116 Ky B.P., ROLANDI et alii, 2003) outcropping along the eastern border of the Plain. A prevalently continental stage follows, consisting mainly of reworked V1 lithologies and detrital-colluvial deposits (Via) produced by the weathering along the carbonate uplands. On top of these deposits and far from the carbonate mountains, transitional units (M2) have been recognized. The pyroclastic flow deposits of the Campanian Grey Tuff (TGC) overlie the two units: they blanket the whole area filling morphologic depressions and dipping gently toward the central region of the Plain. The uppermost unit of the reconstructed stratigraphic succession is represented by thin deposits of the Neapolitan Yellow Tuff (TGN, 15 Ky B.P. DEINO et alii, 2004). A subsequent continental stage is witnessed by Upper Pleistocene to Recent alluvial and detrital-colluvial deposits covering the two volcanic units. The reconstructed geological sections, and the recognition of the depths to the top of the main lithostratigraphic units occurring mainly in the subsurface, has allowed the tectono-sedimentary evolution during the middle-late Pleistocene to be detailed. The main faults displacing the mid-Cenozoic carbonate bedrock have N150-160°, N120° and E-W orientations. They were reactived during the Late Pleistocene (after the deposition of the Ml and V1 units) and resulted in the displacement by about 50 m of the M1 and V1 units toward southwest. Fault planes, active during the Late Pleistocene, are sealed, by the TGC deposits. Locally, even slight displacements of the TGC Unit can be detected. The stratigraphic data have been stored in a MS Access database. Processing of these data into a Geographic Information System (GIS) project has allowed the construction of a digital surface model (DSM) of the bottom and top of the subsurface units. Knowledge of such a geological setting may also represent the basis for correct 'planning and efficient management of this highly urbanized area.