TED2021_EMPHASIS

TRANSPORT OF EMERGING POLLUTANTS IN GROUNDWATER UNDER IN-SITU REMEDIATION CONDITIONS

In accordance with EU Regulation 2020/852 and Spain’s 2021 Ecological Transition Plan, the REMEDIATE project addresses groundwater pollution problems and promotes the decontamination of aquifers. The project deals with the problem of the coastal lagoon of the Mar Menor (Camp de Cartagena, SE of Spain), where the flow of underground water is one of the main carriers of nitrogen into the lagoon generating its eutrophication and an impact serious ecological In this context, the aim of the project is to explore the possibilities of mitigating the mass of nitrogen in the aquifer by identifying its natural denitrification capacity and the possibilities of improving it using in situ remediation methods. In addition, as an added value, the ability of these remedial actions to remove emerging contaminants (EC; pesticides, pharmaceuticals) will also be monitored. This project involves a solid hydrogeological and hydrogeo-biochemical characterization of the study area, with a special emphasis on the peri-lagoon strip of the Mar Menor. On this basis, laboratory experiments will determine the most appropriate denitrification strategies that will be replicated at field scale at a pilot site constructed for this project. The injection of by-products from the agro-food industry will create an appropriate denitrification environment, and its effect on nitrate and EC concentration, isotopic composition and microbial communities will be monitored and modelled. REMEDIATE consists of a coordinated project of 3 partners: University of Barcelona (UB, coordinator), Polytechnic University of Cartagena (UPCT) and Catalan Water Research Institute (ICRA), plus supporting institutions such as IGME, ETH-EAWG (Switzerland) and the private company HydroGeoModels (Switzerland). The results will benefit the environmental recovery of a highly polluted area, promote bioremediation actions and contribute to the scientific development of environmental technologies. The project is also committed to disseminating its results to the main regional agents, consultants and society as a whole. The EMFASIS sub-project, led by the ICRA team, aims to evaluate the evolution of pesticides and pharmaceuticals during the in situ experiment of induced nitrate attenuation at the pilot site. First, the occurrence of these emerging pollutants at a regional level will be characterized, especially near the experimental site. Secondly, its evolution must be monitored under the conditions of induced denitrification. The results will be interpreted on the basis of the geochemical behavior of the ECs in the subsoil supported by the laboratory results carried out by the UB team using groundwater and local substrate, in which the ICRA team will collaborate in the analytical tasks of CEs. Although previous studies already suggest the potential elimination of EC under denitrification conditions, the experiment planned in the Mar Menor area will be one of the first tests carried out at field scale to analyze the elimination of these pollutants in remediation actions . The understanding of these processes and the efficiency of these actions will be of interest for their future application both in the paradigmatic case of the Mar Menor – Camp de Cartagena aquifer and in other hydrogeological systems.