In a humid climate, oxygen barriers are considered as the most effective method to reclaim mine sites that generate acid mine drainage (AMD). The elevated water table technique combined with a monolayer cover is one of these methods. It consists in maintaining the reactive tailings at a high degree of saturation. Because of the low diffusion of oxygen in a saturated material (1000 times lower in water than in air), the flow of oxygen reaching sulphide minerals will be reduced, thereby preventing the generation of AMD.
The design of a monolayer cover with elevated water table is generally made without considering the effect of vegetation, but this may later influence the performance of the cover. Hence the necessity of understanding its effects on the different components of the water balance.
The objective of this project is to better understand and evaluate precisely the influence of vegetation on the water balance of a monolayer cover with an elevated water table.
To do so, the storage facility number 2 of the Manitou site (near Val-d'Or) is used as an experimental site. On this site, experimental plots with and without vegetation have been instrumented in order to evaluate the various components of the water balance. While implementing measuring stations, samples were taken to determine their hydrogeological properties. Finally, the results of the various measurements will be compiled and analyzed to determine the impact of vegetation on the water balance of the cover.