Effect of tailings migration on hydraulic conductivity of mine waste rock

ABSTRACT: Significant amounts of waste rock and tailings (WR&T) are generated by the mining industry, representing a challenge in terms of waste management. Co-placement of WR&T is considered an alternative with positive effects. Nevertheless, countereffects related to the interaction between both materials could arise, particularly due to migration of tailings fine particles inside WR pores. The objective of this work is to improve the understanding of mine WR&T interaction in terms of hydro-geotechnical properties. A series of slurry tailings migration tests within a large column of saturated WR were carried-out. The effect of WR grading was studied testing three different materials with constant dmax=50 mm and different Cu. The results indicate that the retained mass of tailings along the column height reached a maximum value of 20%, showing a homogeneous behaviour of tailings retention through the entire column. The saturated hydraulic conductivity of the WR presents a maximum reduction factor of 13.