A Cover System Model for Dry Stack Tailings

A dry stack tailings storage facility (TSF) generated acid and metalliferous drainage (AMD) and released heavy metals until 2013 when remedial actions were initiated. The Atacama region has a unique climate with very little natural precipitation.

Okane conducted seepage modelling with long-term simulations, considering scenarios involving ongoing tailings placements and the use of irrigation to manage crest wind erosion. The cover system design studies observed the need for a cover system to minimize wind erosion and decrease the infiltration of fluids. An effective cover system would discontinue irrigation (dust control) which was a contributor to water usage on site and the seepage rates through the dry stack tailings structure.

Using instrumentation data, the site model was calibrated to real-world conditions, enhancing confidence in the model's results and illustrating clear outcomes for various cover systems and operational scenarios. Okane's calibrated, site-specific model facilitated informed decisions regarding irrigation, dust control, erosion management, and tailings placement.