The Applied Geology group (formed by a Full Professor, a Associate Professor, three Assistant Professors and several researchers) works in both the Campus Leonardo (Building n. 9) and in the Lecco and Como Campuses.
The group mainly deals with subjects concerning technical geologic and hydrogeology. In particular, issues related to natural resources management and geological risk assessment are dealt with. All these researches develop from a common base, that is the geological and hydrogeological conceptual model reconstruction and they often use numerical models (i.e. for slope stability assessment and groundwater flow and transport simulation), useful to understand the geological system dynamic and to validate the conceptual model.
The main research lines developed within this area include:
• The geological risks related to the implementation of civil engineering works (tunnels, roads, dams, etc.)
The research is aimed at identifying methodologies for analyzing the hydrogeological risk linked to the underground excavation in rocks (water inflow, piezometric drawdown, etc.) and forecasting the landslides hazard. In the first case the research was aimed to calculate the drained flows and the radii of influence and to evaluate the risk, meant as probability that the tunnel inflow or the piezometric drawdown can exceed limit values. The relevant aspect of these studies, as far as their application is concerned, is linked to the possibility of carrying out a probabilistic analysis of the geological risk during the planning of underground construction. This analysis allows to consider the different risky scenarios and to plan all the measures to prevent their occurrence.
• The geological risk related to the land-use planning (landslide risk management)
In the second case the research was aimed to assess the influence of some hydrogeological parameters (as permeability and heterogeneity coefficient) on slope instability. The study has been carried out through the modeling of groundwater flow coupled with the slope stability process, considering several triggering phenomena. The parametrical approach enabled to connect the slope instability to some hydrogeological parameters that are easy to survey and to monitor (e.g. rainfall, piezometrical level and spring discharge). These results provide a scale of the landslide susceptibility concerning the hydrogeological setting (hydrogeological susceptibility), that is very important for both hazard mapping and risk analysis, carried out namely for Civil Protection, in order to prevent disasters due to topples and rockfalls. Rock slopes have been monitored by suitable instrumentation, as laser-scanner and interferometers, in order to outline falls sources and debris trajectories. The debris sources, for the evaluation of sediment budget in rivers have also been outlined, to forecast overflows due to flow section shrinking .
• The geological risk related to the natural resources management (water, rocks and soils, etc.).
The engineering geology group has been involved for several years in the research of sustainable yield definition in groundwater systems. Thanks to a wide groundwater system database built up in last 15 years, the group has achieved a good knowledge of the conceptual model of the Lombardy hydrogeologic system. The research is also oriented towards water resource localization and sustainable management in order to respect, by means of suitable modeling, the hydrogeological balance even in case of human and natural (e.g. climate) changes. The assessment of this research results is performed by collaborating with main public agencies and by means of some monitoring nets of the Milan groundwater wells in order to survey groundwater heads and hydrochemical data. The monitoring nets have been planned by means of the detailed hydrogeological structures reconstruction, achieved with geostatistic methods. The border definition of polluted areas is also fundamental. The research focuses on contaminated site characterization and localization of the pollution sources. For this reason the method of Integral Pumping Test (IPT), has been tested in 2 real cases to localize the contaminant sources of PCE and MTBE and using the IPT results as a new tool for transport models calibration. This method is more efficient if used with the Isotopic Fingerprinting, enabling the prevention of the risk of pollution. By means of fingerprinting the contamination has been dated and the hydrogeochemical evolution of the contamination has been reconstructed. The identification of both original products of the pollution and their evolution enables to describe well the history of the pollution and the related risks, representing an important tool for the characterization of the contaminated sites. Moreover, a method for the prevention of pollution formation after the construction of dangerous work (e.g. landfills) has been prepared even in order to control onset the environmental problems. The application of this method on some real cases allows to verify that the use of both statistic techniques and quantitative risk analysis is necessary to describe the spatial-temporal phenomenon distribution. The pollution problems and groundwater resources management are important issues also in coastal aquifers where salt water intrusion occurs, changing the contamination. The movement of the contamination into a coastal aquifer depends on a complex shape of equi-potential lines along the contact with salt water. Thus the research is oriented toward the understanding of all factors playing a role in this phenomenon. The research group is involved in field surveys and modelization with specific computer codes to study the salt water effects and the contaminant fate near the transition zone. This problem has been studied validating models with real data collected from a contaminated site along the Adriatic coast. These kinds of investigation also allow to predict the interaction between the salt water and hydraulic barrier wells enabling to choose the best solution regarding the intervention management.
University collaborations and Research Institutes: Scaioni M: Tongji University - Department of Surveying and Geo-Informatics Centre for Spatial Data Analysis and Sustainable Development, Grasselli G.: University of Toronto, Vanali M.: Università degli studi di Parma, Festein D.: USGS (USA).
Dialectic critique of Data Processing (ICAR06)
The dialectic critique of Data Processing is located at the crossing point of Geometry, Statistics, Metrology and Epistemology. Indeed Geomatics, which collects and newly interprets all the Survey and Mapping disciplines, recognizes the need to extend its attention from Applied Mathematics and Physics to Human Sciences. Following this path, Linguistics is the starting point, but Philosophy of Science and History of Science and Technique also have to be taken into account to better understand their whole and deep impact. Actually, the most important result shows a "parallelism" not only among stereo-images, 3D models and GIS' geo-database, but also among the geographic descriptive texts of landscapes, human settlements, cultural heritages, etc.