NL FR EN
www.belgium.be

Hydrogeochemical characterisation and modelling of landfill leachates (CHAMOLL)

Projet de recherche BL/52/SA5 (Action de recherche BL)

Personnes :

  • M.  LETERME Bertrand - Centre d'étude de l'Energie nucléaire (CEN) (CEN)
    Partenaire financé belge
    Durée: 15/12/2018-14/12/2021

Description :

DESCRIPTION DU PROJET

SCK•CEN developed integrated simulation tools applicable to different kinds of point source pollutions – ( could also refer to relatively large areas under landfills or mine tailings). For new or suspected pollution problems, historical information on the source term can be easy to obtain, but the costs to acquire detailed, underground site-specific data are often prohibitive. For inorganic contaminants, tests whether reactive models can be used to predict transport in a satisfactory way, with only generic data such as groundwater level data, soil and geochemical maps, topography, etc.

SCK•CEN has expertise in geochemical and reactive transport modelling, using codes such as the Geochemist’s Workbench, PHREEQC, HPx, MT3D, PHT3D…
The School of Chemistry at University of Witwatersrand has expertise in elemental speciation and geochemical modelling, as well as chemometric modelling (incl. optimisation and machine learning methods) for establishing data patterns & drawing relationships amongst the variables that influence water quality.

Cooperation with SCK•CEN can include the characterisation and modelling of complex environmental problems encountered in South-Africa (e.g regarding landfills in Johannesburg lie on old gold mine dumps ...studies to assess the complex processes involved in their evolution). Gold mine dumps tend to release acidic water and several chemotoxic elements, whereas landfills tend to release humic substances together with other contaminants such as polyaromatic hydrocarbons, and chemotoxic components of insecticides and batteries and other electronic items. The challenge is to assess how such mixtures of contaminants react with each other and the geological environment, transform and distribute under complex flow and transport pathways in these heterogeneous systems consisting of tailings, landfills, aquifers and surface water systems. Advanced obust modelling techniques are required for understanding complex processes and assessing impacts. The information yielded by coupled reactive transport modelling & chemometric modelling is crucial in future studies that aim to design remediation strategies.

The anticipated outputs of the networking project include training and intellectual deliverables. Intellectual and personnel outputs include BSc Hons and MSc or PhD graduates from the SA partner; publications, theses and reports; training of personnel through workshops; exchange of information and ideas; and an information resource that will be useful to industry and the community.
Possible socioeconomic benefits include: (i) training of South African and Belgian students in analytical chemistry techniques that are fundamental to the acquisition of environmentally-sound data for risk assessment purposes; (ii) training of SA students in the implementation of geochemical flow and transport processes in state-of-the-art coupled reactive transport models, (iii) the development of environmental models that will be useful as benchmarks for other similar studies.
The collaboration opens perspectives for applying the simulation tools developed by SCK•CEN within RESPONSE on various environmental problems: gold mine dumps, acid mine drainage, landfills… These tools include the HPx model and its extension developed, which ensures that partners interested in using these tools on local problems can receive training and support from SCK•CEN. Future exchange of students and researchers is an option in the future. The networking activities focus on sharing expertise on tools (e.g. HPx) and methods (hydrochemical characterisation of pollutants) transposable to various environmental problems encountered by the partners in their respective research or consultancy projects as well as possible joined research projects in the future.