GWD AMD Talk 2- 3 May 2023

The presentation “Is That Acid Mine Drainage? - A Brief Introduction to Mine Water” provided an overview of mine water, acid mine drainage (AMD), problems associated with mining activities as well as the potential for valorization of mine water. Mine water is the water found in or around mining areas and affected by mining activities. AMD is just one type of mine water characterized by pH values below 5.6. It might pose a risk, as it can produce environmental problems like (semi-metal) contamination of water courses. Examples of mine water problems in South Africa will be presented, including several sites in the Witwatersrand Basin. To understand the situation and problems associated with mine water, it is important to analyse the geochemical and hydrodynamic situation, for instance by conducting water testing. These tests can provide valuable information about the pH value, temperature and electrical conductivity of the water as well as the main ions and trace elements. In-situ remediation and active or passive mine water treatment are common strategies used to address contaminated mine water and will be briefly introduced in the presentation. Monitoring and aftercare as critical aspects of mine water management will also be discussed. The presenters discussed their own research, which includes depth profile measurements, tracer tests, hydrochemical modelling as well as analogue modelling. Finally, the presentation highlights the potential for mine water valorization, where the water is treated and reused for various purposes such as drinking water or geothermal exploitation. South Africa’s potential for the valorization of mine water will be demonstrated by several examples.