Integrated multidisciplinary modeling to support the remediation of contaminated sites

Hydrogeological uniqueness and chemical-physical peculiarities guide the contamination dynamics and decontamination mechanisms in the environmental arena. The experimental work carried out in 3 polluted sites in Italy, exhibiting different geological and contamination contexts, emphasized the contribution of the multitemporal and multidisciplinary geodatabase, which was created for the integrated management, representation, and analysis of different data, to reach a high-resolution characterization of underground geological heterogeneities, aquifers, and contaminated areas. The research aims to demonstrate the contributions of multiple lines of evidence approach to leading to refinement of conceptual site models, assessment of contamination, and successful remediation of contaminated sites. A multiscale approach was followed for the creation of a 3D hydrogeophysical model which acts as an effective “near real time” decision support system able to manage and release data during the different remediation phases from the site characterization up to the proper remediation intervention, all by allowing the user to view, query, and process data in 3D space. The construction of a multi-source conceptual model along with LIF (Laser Induced Fluorescence), ERT (Electrical Resistivity Tomography), and multilevel piezometers, capture the information related to the hydrogeochemical sphere in all its dimensions. The assemblage and the integration of data from the different cited sources has proven to be indispensable in the: characterization and construction of thematic and numeric models, evaluation of intervention techniques, identification of suitable sites to perform the pilot testing, implementation of tests, control and evaluation of the operating conditions at the field scale, design and implementation of full-scale interventions. 3D modeling tools, hydro-geochemical data, and high-resolution detailed site characterization strengthen the conceptual site model. The data-driven model comprises, collects, and establishes a connection between the environmental variables, to optimize the contribution of each aspect supporting the design, implementation, and validation of the remediation techniques. The multi-source geodatabase harmonizes the fusion of data, by generating a digital conceptual model that can be defined as hybrid. The spatial accuracy and dimensionality are preserved, making it a practical reality. The model does not exist within a user interface, the model is the interface supporting the decision-making processes. The hydrogeophysical model and the thematic database act as integrated and continuously updated tools, able to optimize the investigations during the characterization phase, to support the choice of the strategies in planning phase, manage and calibrate in progress the intervention modalities according to innovative approaches during the remediation phase. The research highlights the need for a large amount of multi-source data to build a reliable and high-resolution conceptual model, and to design effective remediation strategies.