Successful transitioning of a conventional slurry tailings storage facility for central thickened discharge

Abstract

A copper mine in Australia operated a perimeter discharge tailings storage facility (TSF) for storage of conventional slurried tailings. In response to regional water shortages, the mine installed a high-rate thickener to dewater the tailings. This provided an opportunity to transition the perimeter discharge TSF for central thickened discharge (CTD). To facilitate the transition, an interim TSF was designed for storage of thickened tailings from the newly commissioned thickener, allowing tailings in the existing TSF to undergo a period of drying and consolidation. During deposition in the interim TSF, a retrofit design was prepared for the existing TSF to allow it to receive centrally deposited thickened tailings while optimising water recovery from the TSF. This paper describes details of the retrofit, including geotechnical and water management considerations and optimisation of the storage layout to ultimately form a dual-mounded system for tailings deposition. The dualmounded layout provides flexibility for cycling of tailings deposition and facilitates perimeter embankment raise construction in phases. The paper describes the design, construction and operational stages of the successful transitioning of the facility.