Innovative approaches to evaluate geochemical risk related to sulphide-bearing Abandoned Mine Lands

Abandoned Mine Lands (AML) are often perceived to have significant environmental impacts, particularly on superficial and ground waters, from water contaminated with acid and elevated metals flowing from eroding waste dumps and from underground workings. These conditions would require risk assessment and remediation in case of necessity. However AML have heritage and historical value because of their age and the significance of their structures and the processes used. This value could be destroyed by remediation done following the environmental law in force. Take into account the particular features of AML (terrains characterised by natural high metal and metalloid concentrations) and environmental law problems (the inability of agencies to cite or allocate clear ownership for the problems at the sites), rise the need to develop an approach that allows the right and complete geo-environmental characterisation of AML and that supports the management and/or the remediation of AML. The main problems related to AML comprise: the identification and characterisation of mine dumps; the assessment of the geochemical hazard; the persistence in time of the chemical processes which occur at the site. Mine dumps are the waste products of exploitation, composed mainly of rocks with metal concentration too low to be economic but rather high to be a source of environmental pollution. A preliminary low-cost identification of mine dumps could be done by means of digital elaboration of topographic maps. This operation allows to identify and to evaluate the morphology and dimension of mine dumps having bibliographic data and CAD software (Servida et al., 2009). Mine dumps characterisation could be completed and refined by Electrical Resistivity Ground Imaging (ERGI) investigations (Mele et al., 2007) that enable to reduce direct investigation number and, consequently, to reduce costs and acquisition time. Moreover ERGI investigations supply 3D information concerning a more extended area. Geochemical hazard related to sulphide-bearing AML could not be evaluated taking into account only the metal and metalloid concentrations of terrains, since it is high by nature. It is suggested to evaluate geochemical hazard starting from the combination of high metal and metalloid concentrations and of the acid production or neutralising potential of terrains by AMIRA procedure (IWRI & EGI, 2002). Hazard evaluation was performed by geostatistical analyses, resulting from 1) the interpolation of the terrain chemical features on the whole area, 2) the overlapping of previous results and 3) the adding of the topographic setting. This approach allows to identify the areas where the presence of metal and metalloids is really hazardous. It also supports the choice of areas that need any treatment. Since AMD processes have a key-role in environmental damages from mining pollution, it is important to know their persistence in time. No studies about this topic have already done. In a preliminary step, the persistence of AMD processes could be calculated starting from common data as yearly rainfall, mining waters pH and acid production or neutralising potential of terrains. The following step is to consider the results of kinetic tests. These approaches have been developed on three pilot sites with different geo-environmental setting: Rio Marina mining district (Elba Island, LI), characterised by hematite + pyrite ore association, exploited for iron from Etruscan age till 1981; Libiola mine (GE), characterised by chalcopyrite + pyrite ore association, exploited for copper from 1864 till 1962; The application of the proposed methodologies and techniques allows a better geo-environmental characterisation of AML. Moreover we think that the proposed approach for the assessment of geochemical risk related to AML could contribute to reduce the areas that need remediation. Consequently will be possible to reduce costs of remediation and impact of remediation on AML

The future of Cybersecurity in Italy: Strategic focus area

This volume has been created as a continuation of the previous one, with the aim of outlining a set of focus areas and actions that the Italian Nation research community considers essential. The book touches many aspects of cyber security, ranging from the definition of the infrastructure and controls needed to organize cyberdefence to the actions and technologies to be developed to be better protected, from the identification of the main technologies to be defended to the proposal of a set of horizontal actions for training, awareness raising, and risk management

Forensic Investigation of Google Assistant

Google Nest devices have seen a rise in demand especially with Google’s huge advantage in search engine results and a complex ecosystem that consists of a range of companion devices and compatible mobile applications integrated and interacting with its virtual assistant, Google Assistant. This study undertakes the forensics extraction and analysis of client-centric and cloud-native data remnants left behind on Android smartphones by the Google Home and Google Assistant apps used to control a Google Nest device. We identified the main database and file system storage location central to the Google Assistant ecosystem. From our analysis, we show forensic artifacts of interest associated with user account information, the chronology and copies of past voice conversations exchanged, and record of deleted data. The findings from this study describe forensic artifacts that could assist forensic investigators and can facilitate a criminal investigation

Mineralogical and geochemical characterisation of open-air tailing and waste-rock dumps from the Libiola Fe-Cu sulphide mine (Eastern Liguria, Italy)

Active acid mine drainage (AMD) processes at the Libiola Fe-Cu sulphides mine are mainly triggered by water–rock interaction occurring within open-air tailing and waste-rock dumps. These processes are mainly controlled by exposure to weathering agents, the grain size of the dumped materials, and by the quantity of sulphides, the sulphide types, and their mode of occurrence. Due to these factors, several paragenetic stages of evolution have been recognised at different depths at different sites and within the same site. The dump samples were investigated with mineralogical (reflected- and transmitted-light optical microscopy, XRPD, and SEM-EDS) and geochemical (ICP-AES, Leco) techniques. The AMD evaluation of the tailing and waste-rock samples was performed by calculating the Maximum Potential Acidity, the Acid Neutralising Capacity, (and the Net Acid Producing Potential. The results allowed us to demonstrate that the open-air tailings had already superseded their AMD apex and are now practically inert material composed mainly of stable goethite ± lepidocrocite ± hematite assemblages. On the contrary, the sulphide-rich waste rocks still have a strong potential to produce long term AMD, causing the acidification of circulating waters and the release of several hazardous elements

Characterisation of sulphide-bearing waste-rock dumps using electrical resistivity imaging: the case study of the Rio Marina mining district (Elba Island, Italy)

Sulphide-bearing mine dumps are potential sources of pollution when acid mine drainage (AMD) occurs. Because the generation of AMD depends on the volume and composition of waste materials, their characterisation is crucial for the evaluation of geochemical hazards and for the design of remediation strategies to minimise their environmental impact. In this paper, a cost-effective strategy for the characterisation of an inactive mine dump in the Rio Marina mining district (Elba Island, Italy) using earth resistivity imaging (ERI) is presented. As no information regarding the nature of waste rocks is found in reports for the mine, five ERI profiles were acquired at the top of the waste pile. The results show that waste rocks are heterogeneous with a maximum thickness of 30 m. Due to the large amounts of dispersed sulphide minerals, the waste rocks are characterised by an electrically conductive geophysical signature in comparison to the surrounding resistive metamorphic bedrock. A geostatistical approach was adopted to estimate the elevation of the edges of the mine dump, and the net volume of the waste rocks was computed through a raster analysis of the elevations of the upper and lower boundaries of the mine dump. High-conductivity anomalies were detected within the core of the mine dump. The integration of the hydrogeological, geochemical and geological framework of the Rio Marina mining district suggests that these anomalies could be a geophysical signature of subsurface regions where AMD is currently generated or stored, thus representing sources of environmental pollution

Phreatic Sulfide-bearing Quartz Breccias (SQB) between Crystalline Basement and Collio Formation (Southern Alps, Italy)

In questo lavoro vengono presentate le caratteristiche geologiche, petrografiche e minerografiche di alcune brecce quarzose mineralizzate a solfuri che affiorano in un\u2019area complessa delle Alpi Orobie (Subalpino), nei pressi dell\u2019area uranifera di Novazza. Sebbene poco studiate, queste brecce sono state attribuite in passato a differenti processi genetici e/o formazioni geologiche (es: Basamento Cristallino, Conglomerato Basale), ma i caratteri riscontrati sembrano confermare una loro origine idrotermale, probabilmente legata allo stesso processo che ha generato il giacimento di U a Novazza

Application of Electrical Resistivity Ground Imaging (ERGI) to aid the Acid Mine Drainage (AMD) evaluation in the Rio Marina mining district (Elba Island)

The Rio Marina mining district (Elba island) was one of the greatest Italian iron ore and was exploited till 1981. Nowadays it is used as an excursion site and it is famous all around the world for its hematite-pyrite mineralogical samples and for its multi-colour acid pools. These pools are related to Acid Mining Drainage (AMD) process that occur in the sulfide-mining area. The effect of open-pit mining and other mining-related activities is that sulfides, previously isolated from the atmosphere, are exposed to oxygen. The oxidation of sulfides acidifies the flowing waters that leach ore minerals and dissolve elements such as arsenic, copper, manganese, iron, lead and zinc. This process leads to environmental pollution. The Rio Marina mining district is currently object of a geo-environmental characterization to assess hazard and persistence of the AMD process (Servida et al. 2006). In addition to investigations on surface waters, terrains and topographic evolution of the mining site, a geo-environmental model aiming to AMD evaluation requires the determination of: 1) waste rock thickness, to evaluate the amount of sulfuric acid that could be produced and the content of heavy metals that could be leached from terrains; 2) distribution of sulfides in the waste deposits; 3) distribution of the water-rich zones in waste deposits. The aim of this work is to supply these data by means of 2-D Electrical Resistivity Ground Imaging (ERGI) techniques. The pilot-study was performed on the Antenna plains, which represent one of the waste disposals of Rio Marina district. This area was chosen since 3-D topographical modelling, field survey and bibliographic data show no certain information concerning the thickness of the waste deposits. The following procedure was adopted: 1)acquisition of five ERGI profiles over the Antenna plains and identification of bodies showing homogeneous distribution of electrical resistivity. ERGI profiles were acquired by means of Wenner-Schlumberger array with 44 electrodes, with electrodes-spacing ranging from 3.0 to 5.0 m (maximum depth of investigation = 40.0 m). Profiles were acquired on a square grid in order to investigate the 3-D features of the subsurface; 2) direct-calibration of electrical resistivity class-values of bedrock (60-150 Ohm*m) and hematite-pyrite mineralized ore bodies (10-30 Ohm*m) by acquisition of 1 ERGI profile (Wenner-Schlumberger array; 30 electrodes, electrode-spacing = 2,5 m) located on an exposed quarry bench in the proximity of the Antenna plains; 3) interpretation of electrical resistivity distribution obtained by ERGI profiles by the light of a) the model of subsurface from 1954-1979 topographic and mining maps, b) knowledge of ore-geological model of the mining area, c) electrical resistivity obtained from the direct-calibration made on the outcropping analogue materials, d) physical and chemical properties of surface waters and terrains; 4) 3-D interpolation by geostatistical analysis (kriging) of the boundary between the electrical resistivity bodies correlated to bedrock-ore bodies complex and the hypothesized waste deposits. The results show that: 1) Antenna plains are composed by waste deposits with a maximum depth of about 25.0 m. These data confirm that Antenna was an old open-pit used as a mine-waste dump; 2) waste deposits have highly-conductive homogeneous electrical properties (<10 Ohm*m) and, consequently, they could have an homogeneous water-content and chemical composition. The low resistivity value is due to the high conductivity of groundwater (average groundwater conductivity: 7.54 mS/cm = 1.3 Ohm*m) and the occurrence of clay minerals produced by in-situ weathering of bedrock and debris; 3) bedrock has highly-conductive anomalies (10-30 Ohm*m) that, from their geometry, position and electrical resistivity values, could be interpreted as hematite-pyrite mineralized ore bodies

Functional differences between dendritic cells derived from CD34+ bone marrow and peripheral blood stem cells

Background and Objectives. It has been previously demonstrated that dendritic cells (DCs) are characterized by an immature stage with high antigen internalization capacity, followed by a mature stage with predominantly immunostimulatory ability. The shift from the immature to the mature state can be induced in vitro by the addition of tumor necrosis factor-\u3b1 (TNF\u3b1). The aim of our study was to investigate the maturation steps of DCs obtained from CD34+ cells from peripheral blood stem cells (PBSC) and bone marrow (BM). Design and Methods. DCs were generated in vitro from PBSC and BM CD34+ selected cells. The endocytic activity of the cells was measured by means of dextran-FITC uptake and alloreactivity evaluated with mixed leukocyte reactions. Immunophenotypic analysis was performed by flow cytometry. Results. We observed that DCs from PBSC, in contrast to the BM derived DCs, were never able to take up soluble antigens. Mixed leukocyte reaction (MLR) performed both on PBSC and BM CD34+ derived DCs showed an allo-stimulatory activity comparable to normal controls at day 10, but significantly higher at day 14 after the addition of TNF\u3b1. Immunophenotypic analysis showed typical dendritic markers in all the samples and, after treatment with TNF\u3b1, enhanced expression of co-stimulatory molecules. Interpretation and Conclusions. Our data seem to indicate that, in our culture conditions. BM-derived DCs could be efficiently used for pulsing with specific peptides, while PBSC-derived DC, being functionally mature, should be more suitable for gene therapy. (C) 2000, Ferrata Storti Foundation