WP4: Mine waste management

Objective

This WP focuses on prevention of formation of contaminated drainage from mine waste produced during gold extractions in case study sites at Sweden, Finland, Portugal and Romania. Mine waste management and stabilisation of mine wastes by using paste technology will be assessed and a detailed geochemical characterisation of the mine wastes and paste, as well as the drainage generated will be implemented. This WP focuses also to the function of the multi-layer covers for tailings disposal, including a layer with oxygen consuming materials and safety related to dam permeability and slope stability.

Approach

Arsenic-rich tailings will be stabilized with paste technology, with addition of alkaline by-products from other industries. The resulted matrix formed will be mineralogical and chemical characterized and the long-term stability evaluated. Small-scale field tests will be carried out to characterize the time evolution of the drainage originated by paste deposition. The waste materials produced during mine water treatment with adsorbents (WP3) will be characterized and also tested using the direct magneto-electrowinning cell developed for WP2. A comparison set of results will be produced in this WP and methods for the deposition of waste materials will be evaluated. All geological information will be corroborated with in situ geophysical tests in order to estimate the permeability of the rocks situated beneath the tailing dams.

  • Characterization of the As-rich paste tailings
  • Long-term stability of tailings
  • Long-term stability and impermeability of the dam structures
  • Multilayer cover structure

Expected results

Development of methods such as paste technology to prevent harmful drainage to be produced from mine wastes and evaluation of the long-term stability can be used during the planning of treatment and management of mining wastes. The evaluation of the long-term stability of mine wastes produced from different gold extractions can be used when planning the treatment and management of mining wastes.