Evaluation and Prediction of Seepage Discharge Through Tailings Dams When Their Height Increases 

Abstract

Significant seepage through tailings dams is one of the main disadvantages of upstream dams. In some cases, seepage through dams can lead to large water losses from recycling system of the dressing plant. Seepage evaluation should be carried out when designing of dams’ height increase in a framework of water balance prediction. In this chapter, the authors present the results of evaluations of seepage through dams of a large tailings storage (with total area of 17.5 km² and with dam’s average height of 62 m as of 2017) performed by both field hydrometric measurements and analytical calculations. For seepage analytical calculations, the grain size distribution data of 327 samples of wet magnetic separation (WMS) tailings were used to obtain the hydraulic conductivity (K) on the basis of empirical equations. The results of the seepage evaluation performed using both approaches were compared. It was shown that the results of the seepage evaluation obtained in the framework of hydrometric studies and analytical calculations are well comparable. Taking into consideration good comparability of the results, the Dupuit equations were used for prediction of seepage discharge through the tailings dams in case of their raising, according to design decision, to 28 m in average for the next 10 years.