Hydrogeochemical Model Supporting the Remediation Strategy of a Highly Contaminated Industrial Site

Abstract

Delineation and understanding the geology and the hydrogeology of a contaminated site, considering its chemical and its biological aspects, are fundamental requirements for successful environmental remediation. The aim of this research is to provide some evidence about the effectiveness of a hydrogeochemical geodatabase to facilitate the integrated management, representation and analysis of heterogeneous data, enabling the appropriate selection, design and optimization of an effective remediation strategy. This study investigates a new technology for the remediation of a dense non-aqueous phase liquid aged source zone, with the aim of enhancing in situ bioremediation by coupling groundwater circulation wells with a continuous production system of electron donors. The technology was verified through a pilot test carried out at an industrial site highly contaminated by chlorinated aliphatic hydrocarbons. The multidisciplinary conceptual model confirmed a complex hydrogeological situation, with the occurrence of active residual sources in low permeability layers. The pilot test results clearly demonstrate a significant mobilization of contaminants from the low permeability zone, and the possibility of favoring the in situ natural attenuation mechanisms based upon biological reductive dechlorination. Different information related to the hydrogeochemical sphere must be integrated and taken into consideration when developing a reliable remediation strategy for contaminated sites.

Biochar from Pine Wood, Rice Husks and Iron-Eupatorium Shrubs for Remediation Applications: Surface Characterization and Experimental Tests for Trichloroethylene Removal

“…The distribution of Chlorinated Solvents, such as Perchloroethylene (PCE) and Trichloroethylene (TCE), in solid and liquid matrix of the subsoil is a process that depends not only on the chemical and physical characteristics, but also on the hydrological characteristics of the site. In general, many years after the primary source of contamination has been removed, chlorinated solvents act as persistent, slow-release sources in the saturated area at very low concentrations [ 1 , 2 ].…”

An Integrated Approach Supporting Remediation of an Aquifer Contaminated with Chlorinated Solvents by a Combination of Adsorption and Biodegradation

“…A large amount of multithematic data was stored and centralized in an integrated information management and analysis platform. The integrated geodatabase represents an effective near-real-time decision support system (DSS) able to manage and release data during the different remediation phases, from characterization to technique implementation, in the field test and at full scale [26]. The hydrogeological model analysis and selection of a remediation technology utilized multiscale and multiphase approaches [32].…”

“…The proper collection, storage, representation, and integration of geothematic data from different sources are key aspects in defining reliable remediation strategies for contaminated sites [14]. The creation of a "4D" geographical database (which also considers the time factor) enables the integrated management, representation, and analysis of different data (geological, hydrogeological, geophysical, and chemical) [26]. The multitemporal and multidisciplinary geodatabase assumes the role of an effective "near real time" decision support system (DSS) [26][27][28] able to manage and release data from characterization to implementation of the technique.…”

“…The creation of a "4D" geographical database (which also considers the time factor) enables the integrated management, representation, and analysis of different data (geological, hydrogeological, geophysical, and chemical) [26]. The multitemporal and multidisciplinary geodatabase assumes the role of an effective "near real time" decision support system (DSS) [26][27][28] able to manage and release data from characterization to implementation of the technique. The 3D georeferenced model extracts useful information for the decision-making process quickly and in a versatile way.…”

Analytical and Numerical Methods for a Preliminary Assessment of the Remediation Time of Pump and Treat Systems

“…In literature, different formulations exist with different complexity, depending on the transport processes and the contaminant considered. The formulations range from the evaluation of the number of pore volumes that are necessary to flush in order to reach the clean-up target concentrations [16,25], numerical models set up for site-specific conditions or specific processes [26][27][28][29], and numerical models coupled with genetic algorithms [30][31][32][33][34][35][36][37].…”