ChargeHet – Charge interactions and electrostatic Heterogeneity: the hidden control on contaminant transport in groundwater

• Applicant: Professor Dr. Massimo Rolle, Ph.D.
• Subject Area: Hydrogeology, Hydrology, Limnology, Urban Water Management, Water Chemistry, Integrated Water Resources Management
• Term: since 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 537283170

Most groundwater contaminants are electrostatically charged and Coulombic interactions are ubiquitous in the subsurface. The aim of this project is to explore the fundamental coupling of electrostatic interactions with the physics of flow and transport in complex heterogeneous media and with the chemistry of aqueous solutions and solid/solution interfaces. The novel approach is based on the experimental investigation of charge interactions in different sandy and clayey porous media and on a Nernst-Planck formulation for transport of major ions and charged tracers. The planned experiments include multidimensional flow-through experiments in physically, chemically and electrostatically heterogeneous porous media, as well as batch investigation of solid/solution interactions between charged compounds and charged surfaces. The experiments will be quantitatively interpreted with numerical simulations, performed at both pore and continuum scales, based on a rigorous description of Coulombic interactions in pore water, diffuse layer processes and surface complexation reactions. The developed numerical simulators will be instrumental to extend the mechanistic findings of the investigation beyond the spatial and temporal scales covered by the experiments, allowing us to explore field-scale scenarios with complex distribution of physical, chemical and electrostatic properties. The ChargeHet project will advance the understanding to the global challenge of groundwater contamination by approaching it as an electrostatic environmental problem and by disclosing the controlling role of microscopic Coulombic interactions, the importance of dimensionality, and the overlooked relevance of chemical and electrostatic heterogeneity.

• DFG Programme: Research Grants
• International Connection: Finland
• Cooperation Partner: Dr. Muhammad Muniruzzaman, Ph.D.