Valutazione dello stato di qualità ambientale delle aree agricole ai sensi del D.M. 46/2019

This work illustrates one of the first cases of application of Ministerial Decree no. 46 of 1 March 2019 to a large potentially contaminated area of Southern Italy. The study conducted concerned the design and execution of a series of investigations to understand and define the state of environmental quality and related health aspects of agricultural soils falling within the study area. To this end, the CNR IRSA of Bari has drawn up, pursuant to Art. 3 of Annex 1 of Ministerial Decree 46/2019, an Investigation Plan aimed at understanding the environmental/health aspects and the risk assessment of the aforementioned areas. In this context, starting from the theoretical definitions of Ministerial Decree 46/2019, new operational approaches were tested for the characterization of agricultural areas, developing a methodology for the definition of the criteria for identifying the so-called "homogeneous areas", which takes into account the site conditions -specifications and technical-scientific documentation available. The tested method involved the use of very different analysis strategies, integrated with innovative methods of assessing the contamination found in the survey area. The criteria taken into account for identifying the "homogeneous areas" were: 1) assessment of significant land changes, through change detection surveys and analysis of land use; 2) analysis of cadastral data, considering that different cadastral parcels could correspond to different owners and, therefore, different agronomic practices; 3) analysis of the Soil Map and pedological characterization, applying a geological-geomorphological criterion and identifying, within each site of investigation, morphologically homogeneous areas to which are associated tendentially homogeneous soils; 4) analysis of land use and detail of agricultural species; 5) analysis of orthophotos and satellite images, in order to make any necessary corrections. Within each homogeneous area, elementary soil samples will be taken and mixed to constitute a composite sample, representative of the homogeneous area, on which laboratory analyses will be carried out. On-site investigations and analyses of soil samples are still in progress. Should the outcome of the investigations ascertain that the values of the Contamination Threshold Concentrations (CTC) fixed by the Italian Environmental law have been exceeded, even for just one of the contaminants sought in the soils, as required by Ministerial Decree 46/2019, in-depth analyses are envisaged on agri-food products and, if necessary, also on soils. In addition, the results of surface soil investigations will be integrated with the results of the monitoring which, at the same time, it is taking place on groundwater and air because they must necessarily be taken into account in the definition of the Final Conceptual Environmental and Sanitary Model for agricultural areas. Finally, the application of vis-NIR spectroscopy is envisaged as an innovative technique for the rapid control of any anomalies resulting from the chemical analysis of composite soil samples and for the assessment of the chemical-physical characteristics of the individual elementary soil samples that make up the composite, to verify its effective homogeneity.