Planning the Dewatering of a Tailings Storage Facility

Abstract

The San Rafael mine in southern Peru produces over 10% of the world’s tin. The decision was made to reprocess some of its oldest tailings, due to their volume and high tin concentrations. This tailing storage facility was partially saturated and required a dewatering process to allow mining. This paper describes the conducted activities for this dewatering, including basic engineering studies focused on hydrogeological characterization of the tailings, recommended tests and modelling to define a detailed engineering design, and developing an appropriate construction strategy. In addition, there were tasks associated with operating the dewatering system, infrastructure maintenance, and a real-time follow-up implementation program to monitor the desaturation. The system’s historical evolution, a year of dewatering, and the beginning of mining activities are reviewed.