Stochastic stope design optimisation under grade uncertainty and dynamic development costs

Stope design optimisation defines three-dimensional extraction volumes aiming to maximise cashflows, subject geotechnical and operational constraints. Available stope layout methods are deterministic, failing account for grade uncertainty variability that affect locations sizes, as well value. A two-stage stochastic integer programming model is proposed, integrating quantified through geostatistical simulations, level allocation, variable pillar sizes different zones, development costs. An application at an underground gold mine employing sublevel open stoping highlights the integration management of define risk-resilient design.