Evaluation of Slope Stability of Tailings Storage Facility under Static and Seismic Conditions

This study showcases a comprehensive geotechnical and geophysical investigation of a tailings storage facility embankment, integrating geotechnical borings with Electrical Resistivity Tomography (ERT) and Multichannel Analysis of Surface Waves (MASW) to characterize subsurface conditions. Geotechnical borings provided essential soil property data, while ERT was utilized to investigate variations in moisture content and potential void spaces within the embankment. MASW testing was used to determine shear wave velocity profiles, which are essential for seismic site classification and evaluating the dynamic properties of embankment materials. The primary objectives of this study were to evaluate the stability and integrity of the tailings storage facility embankment and assess the performance of the tailings liner system. The integration of these subsurface investigation methods enabled a more comprehensive subsurface characterization. Using this subsurface information, limit equilibrium slope stability analyses were performed under static and pseudo-static conditions to assess the stability of the tailings storage facility. In this study, both global and shallow failure modes were considered. Factors of safety were calculated for slope stability evaluation. Additionally, a Newmark displacement analysis was performed to assess earthquake-induced displacements, considering variations in the dynamic soil properties of the embankment materials. Newmark displacement analyses incorporated seismic data from the 2014 and 2023 National Seismic Hazard Models (NSHM), accounting for recent increases in regional seismicity. These findings provide valuable insights for slope stability evaluation and subsurface characterization of the tailings storage facility.