Martin, V, Aubertin, M, Benzaazoua, M & Zhan, G 2010, 'Investigation of near-surface exchange processes in reactive paste tailings', in R Jewell & AB Fourie (eds), Paste 2010: Proceedings of the Thirteenth International Seminar on Paste and Thickened Tailings, Australian Centre for Geomechanics, Perth, pp. 265-278, https://doi.org/10.36487/ACG_rep/1063_23_Martin
(https://papers.acg.uwa.edu.au/p/1063_23_Martin/)
Abstract: The use of paste tailings is considered as a potentially advantageous alternative to conventional slurry 
tailings disposal, especially in areas where water resources are scarce. In order to assess the response of a 
paste tailings storage facility, one needs to analyse the near-surface moisture fluxes in the exposed tailings 
due to evaporation and drainage. In the case of sulphide bearing materials with an acid mine drainage 
(AMD) generating potential, it is important to evaluate the impact of desaturation that may lead to tailings 
weathering, i.e. oxidation. A key factor influencing production of AMD is the distribution of the pore water 
within the tailings.  
This paper presents sample results from laboratory testing and numerical simulations that are being 
conducted to evaluate pore water movements in surface paste tailings. The study focuses primarily on 
columns tests made with paste tailings from Barrick Gold’s Bulyanhulu Mine (Tanzania, Africa). These tests 
have been used to assess the evolution of paste tailings behaviour and their reactivity at the laboratory scale, 
with the help of numerical simulations. The oxidation rate is also investigated for different situations 
pertaining to the column tests results. The numerical simulations presented are a one-dimensional 
simplification of the tailings storage facility of Bulyanhulu Mine, and evaluate the impact of evaporation on 
the water balance of paste tailings deposited on surface. The main observations indicate that the oxidation of 
exposed reactive tailings is influenced by their degree of saturation and the evaporation plays an important 
role in the water balance of paste tailings exposed to near surface conditions.