Open-pit Coal Mine Waste Dump 4D Topography Monitoring using UAV Technology - A Review

ABSTRACT: Large open-pit coal mining projects traditionally rely on total station and terrestrial laser scanner (TLS) for monitoring overburden (OB) dump and slopes. However, as mines expand, the stripping ratio increases, generating massive volumes of OB material, often deposited in unplanned ways. With dump heights exceeding several hundred meters, external triggers like intense rainfall, and seismic activity can cause catastrophic slope failures - posing serious risks to safety, equipment and productivity. In response, this study highlights the importance of real-time monitoring for safe and sustainable OB dump management. With the advent of Mining 4.0, unmanned aerial vehicles (UAVs) have become a reliable, cost-effective solution for high-precision monitoring of large dump areas. UAV-enabled 3D change detection techniques offer an effective way to identify and mitigate geotechnical hazards. This review presents a comprehensive and innovative dump monitoring framework, emphasizing a novel Multimodal 4D Point Cloud (X, Y, Z, time) technique. The proposed method enhances the ability to monitor displacement trends over time and supports data-driven decision-making for slope stability and waste dump management. The integrated approach aims to help the mining industry better understand field conditions and ensure safer, more resilient operations.