Magnoni M.,ARPA Piemonte
EPJ Web of Conferences | Year: 2012
The atmospheric re-suspension of radionuclides is a well-known phenomenon that consists in the re-injection into the atmosphere of previously deposited radioactivity. The process is driven by the action of wind on surfaces and can act as an additional source of radiation exposure by inhalation, after the deposition has finished. It is thus defined as the re-suspension factor, a parameter K generally considered as a time depending function and defined as the ratio of Ca, the volumetric air activity concentration (Bq m -3) and I0 (Bq m-2), the radioactivity deposition at time zero. The re-suspension factor concept is very useful in radioprotection in order to estimate the inhalation of radionuclides re-suspended from contaminated surfaces when direct atmospheric measurements are lacking or difficult to perform. However, the choice of the proper values of K is usually not a simple task, being quite site-specific and related to the meteorological, geomorphologic and environmental characteristics of the area to be studied. Moreover, several investigations showed clearly that the values of K are a decreasing function of time. For that reason, K values span several orders of magnitude: typical values in the range 10-5-10 -10 m-1 are reported in literature for different environmental conditions and time elapsed since the deposition event. The current available models for the re-suspension factor are based on empirical formulas whose parameters are highly site dependent and cannot easily be related to some physical quantity. In this paper a simple physical model for the re-suspension factor is proposed and tested with available environmental radioactivity data (137Cs), collected since 1986 (Chernobyl fallout). The new model not only allows a satisfactory description of the experimental data like even the current empirical models do, but it is also able to connect the K values to quantities with a physical meaning (such as, for example a diffusion-dispersion coefficient) and that are related to processes underlying resuspension. © Owned by the authors, published by EDP Sciences -SIF, 2012.
Blengini G.A.,Polytechnic University of Turin |
Blengini G.A.,CNR Institute of Environmental Geology and Geoengineering |
Brizio E.,ARPA Piemonte |
Cibrario M.,Polytechnic University of Turin |
Genon G.,Polytechnic University of Turin
Resources, Conservation and Recycling | Year: 2011
Given the booming of bioenergy plants under construction in Piedmont, in Northern Italy, Life Cycle Assessment (LCA) was used in order to assist public decision-makers during the evaluation of new bioenergy projects. Local administrators are in fact worried that public incentives granted to bioenergy producers, regardless of the overall environmental performance, might not encourage technological innovation and eco-efficiency, or bring unwanted indirect environmental effects. A detailed LCA of bioenergy production from dedicated crops (maize, sorghum, triticale and miscanthus) and manure through anaerobic digestion and combined heat and power generation was carried out. The LCA model was particularly focused on the end-of-life of digestate and site-specific data related to the impact of adopted energy conversion technologies. It was confirmed that bioenergy is not automatically synonymous with sustainable energy, as the differences in terms of environmental performance can be remarkable. EROI (Energy Return on Investment) index was estimated to be 3-5. The potential in terms of GHG saving depends on several factors and it is heavily influenced by the reference non-renewable energy to be substituted. End-of-life of digestate was found to be crucial for acidification and eutrophication, but also for GHG emissions. Finally, particulates equivalent emissions were found to be very large in comparison to modern natural gas power plants. © 2011 Elsevier B.V. All rights reserved.
Panepinto D.,Polytechnic University of Turin |
Brizio E.,ARPA Piemonte |
Genon G.,Polytechnic University of Turin
Clean Technologies and Environmental Policy | Year: 2014
In order to improve the air quality in some very critical areas in Europe, it is required to limit the contaminant flux coming from different sources (thermal and industrial plants, transport systems, cars, and other technological apparatus). This limitation in many cases corresponds to important investment costs, and normally to a substantial increase in the operative costs; but, from the other side, by the intervention on the emitted pollutant loads it can be obtained a condition of better air quality, with consequent lower externality costs, chiefly with reference to the exposed population. By comparing the two aspects of increasing costs, and in particular the slope of the increasing trend, and from the other side the improvement in air quality, it is possible to identify as a compromise a convenient definition of the optimal intervention that must be realized, and it is possible to establish the performances that must be obtained, by arriving to an acceptable air quality with a sustainable cost. This strategy of identification of the optimal point between these two opposite trends has been illustrated in the present work, and some practical examples of implementation of different limitation strategies and consequent environmental results are presented; these results concern different scale solutions, and different geographic situations. © 2014 Springer-Verlag Berlin Heidelberg.
Fabietti G.,University of Turin |
Biasioli M.,University of Turin |
Barberis R.,ARPA Piemonte |
Ajmone-Marsan F.,University of Turin
Journal of Soils and Sediments | Year: 2010
Background, aim, and scope Diffuse soil contamination has often been neglected in scientific literature, as most studies focus on contaminants from point-sources (either of industrial or agricultural origin). However, soil pollution from diffuse sources is recognized as one of the major soil threats by the EU Soil Thematic Strategy. In fact, some pollutants are nowadays ubiquitarious in the soil system, and they have to be considered for the implementation of environmental legislation, the definition of clean-up values in remediation activities and, more generally, for a sustainable management of rural areas. In the literature large scale studies on diffuse contamination are few and scattered and often do not consider a wide range of contaminants, the effect of land use, the vertical variability and the potential natural contribution. Aim of this work was to provide an overview of the diffuse soil contamination on a regional scale for a large set of contaminants. Soil inorganic (Cd, Cr, Ni, Pb, Cu, Zn) and organic contaminants (polychlorinated dibenzo-p-dioxins(PCDD), polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs) as well as other soil general parameters were investigated on a 18×18 km grid covering a whole Italian region heavily industrialized and intensively cultivated. Soils were sampled at different depths both for natural-undisturbed soil and for agricultural-plow soil. Differences in the trends of investigated contaminants, as a consequence of land use, vertical variability, natural or geogenic origin, relationships among contaminants, and with main soil properties, were explored by means of enrichment factors, bi- and multi-variate statistics. Materials and methods The sampling scheme of this study is based on a systematic 18×18 km grid covering the whole region. Overall, 43 monitoring sites located at the center of each cell were sampled. At each site, five individual core samples within a 10×10 m area were taken at different depths for natural-undisturbed soil (topsoil 0-10 cm, subsoil 10-30 cm) and for agricultural-plow soil (topsoil Ap horizon, subsoil 20 cm below the Ap lower limit). Samples were processed for general soil properties as well as for organic (PAHs, PCBs, PCDDs/dibenzofurans (DFs)) and inorganic (Cd, Cr, Ni, Pb, Cu, Zn) contaminants analyses (aqua regia digestions). Contaminants were detected after extraction by means of ICP-MS and GCMS. Statistical analysis was conducted using the software SPSS 13 (SPSS) and Minitab 15 (MINITAB). Data were geographically managed and processed with the Arcview 3.2 (ESRI, CA, USA) GIS software. Results Organic contaminants such as PCDDs were found to accumulate in natural areas while inorganics mostly concentrate in agricultural soils, confirming the presence of important phenomena of long-range diffuse contamination for the first and short-range for the latter. Soil use was also confirmed to be a major parameter in influencing the type, degree, and distribution of contaminants. Vertical variability was found to be high for organic contaminants and for Pb, suggesting their main anthropogenic origin, while other elements such as Cr and Ni appeared to be more related to the natural background. Data were compared with those from soils of a large industrial city present in the area, confirming the strong enrichment of the urban environment with respect to some contaminants such as metals, PCBs, and PAHs. Other contaminants such as PCDD/DFs showed lower differences, confirming their diffuse and almost ubiquitarious pollution. Discussion and conclusions Even if natural soils in this study are mostly located far from major sources of contamination, notable differences appeared when compared to agricultural areas. In particular, the enrichment in the concentrations of organic contaminants such as PCDDs in natural areas and of inorganics in agricultural soils confirm the presence of important phenomena of longrange diffuse contamination for the first and short-range for the latter, which appeared also to be related to agricultural activities. Contaminants like PCDDs, PCBs, PAHs, and Pb presented high vertical variability, confirming their anthropogenic origin and strong affinity to soil organic matter, while others appear to be more related to the natural background. The comparison of data with those from soils within a large-industrial city present in the study area confirms the strong enrichment of the urban environment with respect to some contaminants such as metals, PCBs, and PAHs. Other contaminants such as PCDD/DFs showed lower differences confirming their diffuse and ubiquitarious pollution. Recommendations and perspectives Soil diffuse contamination revealed to be an important source for some contaminants that appear to distribute over a large scale. The type of land use strongly influences the distribution of pollutants in soils, by diluting them in depth (plowing in agricultural areas) or concentrating contaminants in the surface (natural areas or meadows). Data provided in this study constitute an important dataset of the soil environmental quality on a large scale that can be used for the development of guidelines for soil management, the definition of local clean-up values, and the implementation of risk assessment procedures. © Springer-Verlag 2009.
Oberto E.,ARPA Piemonte |
Milelli M.,ARPA Piemonte |
Pasi F.,Consorzio LAMMA |
Gozzini B.,CNR Institute for Biometeorology
Natural Hazards and Earth System Sciences | Year: 2012
The demand for verification of numerical models is still very high, especially for what concerns the operational Quantitative Precipitation Forecast (QPF) used, among others, for evaluating the issuing of warnings to the population. In this study, a comparative verification of the QPF, predicted by two operational Limited Area Models (LAMs) for the Italian territory is presented: COSMO-I7 (developed in the framework of the COSMO Consortium) and WRF-NMM (developed at NOAA-NCEP). The observational dataset is the precipitation recorded by the high-resolution non-GTS rain gauges network of the National Civil Protection Department (NCPD) over two years (2007-2008). Observed and forecasted precipitation have been treated as areal quantity (areal average of the values accumulated in 6 and 24 h periods) over the 102 "warning areas", defined by the NCPD both for administrative and hydrological purposes. Statistics are presented through a series of conventional indices (BIAS, POD and POFD) and, in addition, the Extreme Dependency Score (EDS) and the Base Rate (BS or 1-BS) have been used for keeping into account the vanishing of the indices as the events become rare. Results for long-period verification (the whole 2 yr) with increasing thresholds, seasonal trend (3 months period), diurnal error cycle and error maps, are presented. Results indicate that WRF has a general tendency of QPF overestimation for low thresholds and underestimation for higher ones, while COSMO-I7 tends to overestimate for all thresholds. Both models show a seasonal trend, with a bigger overestimation during summer and spring, while during autumn and winter the models tend to be more accurate. © 2012 Author(s).