Historic Tailing Dam Failures through the Application of InSAR Technologies - A Discussion of Grace Mine Based on Sentinel Data

Tailing dam failures present significant risks to environmental stability and human safety, releasing toxic materials and causing widespread destruction. This study utilizes Interferometric Synthetic Aperture Radar (InSAR) technology, particularly Persistent Scatterer Interferometry (PS-InSAR) and Small Baseline Subset (SABS) methodologies, to analyze surface deformations associated with the catastrophic failure of the Jagersfontein tailing dam in South Africa. Leveraging Sentinel-1 data collected over a six-year period (three years before and after the failure), the research focuses on identifying key deformation patterns, structural instabilities, and potential precursors to the collapse. The integration of PS-InSAR and SABS techniques allows for precise tracking of subsidence and uplift within the dam structure, revealing distinct zones of risk that correlate with observed failure points. Additionally, Sentinel-2 data is employed to track water body dynamics and assess environmental impacts, utilizing the Normalized Difference Water Index (NDWI) to highlight changes in water distribution and moisture content around the dam site. Results indicate significant subsidence in areas near the dam foundation, combined with localized uplift likely due to material stress redistribution. These deformation patterns serve as crucial indicators of impending failure, emphasizing the utility of InSAR technology for real-time hazard assessment and early warning systems in high-risk mining environments.