Practical Experience of Filtered Tailings Technology in Chile and Peru: An Environmentally Friendly Solution

Abstract

In the last 20 years many mining projects around the world have applied a tailings deposition technology named “dry stacking of filtered tailings” at tailings storage facilities (TSFs). This technique produces an unsaturated cake that allows storing this material without the need to manage large slurry tailings ponds. The application of this technology has accomplished: (i) an increase in tailings water recovery, (ii) a reduction of the TSF footprint (impacted areas), and (iii) a decrease in the risk of physical instability, being TSFs self-supporting structures under compaction (such as dry stacks), and (iv) a better regulator and community perception satisfying the need of stable TSFs. This paper presents the main features, benefits, and advances in filtered tailings technology applied in Chile and Peru with emphasis on: (i) filtering technology evolution over the last decade: description of main equipment, advantages, and disadvantages, (ii) design considerations for main TSF geometrical configurations, tailings transport and placement systems, TSF water management, TSF operational and emergency plans, and TSF progressive closure, (iii) operation experiences at site-specific conditions, (iv) technology acceptance in regulatory frameworks, (v) lessons learned and advances, and (vi) new trends and future developments, considering technical, environmental, regulatory frameworks and cost-effective manners.