Sustainable Slope Stability Assessment and Landslide Risk Mitigation Using Integrated Geophysical and Geotechnical Approaches in the Atika Tunggal Mandiri Mining Area

This study addresses a critical topic in geotechnical and geophysical engineering: the assessment of slope stability in mining environments. The integration of seismic refraction tomography (SRT), limit equilibrium methods (LEM), and GIS-based mapping represents a timely and relevant approach, particularly for landslide-prone regions in Southeast Asia. This study investigates slope stability and subsurface characteristics in a geologically complex area through the combined application of seismic refraction tomography (SRT) and limit equilibrium methods (LEM). Seismic refraction measurements were performed along five profiles (L-1 to L-5), ranging from 45 m to 110 m in length, utilizing 12 geophones spaced 10 m apart and a DataQ DI-710 data logger for recording. The seismic data were processed using WindaQ Software 3.10, which revealed distinct subsurface layers, including clay and andesite, with variations in thickness and material properties. Slope stability analysis was performed using limit equilibrium methods (LEM), incorporating the Fellenius, Bishop, Janbu, Spencer, and Morgenstern-Price approaches, as implemented in Rocscience SLIDE Version 6.0. The factor of safety (FoS) was computed for all five slopes, confirming stability (FoS > 1) in every case. The lowest FoS (2.70) was observed in L-4, likely due to its greater height and steeper slope, while the highest FoS (4.60) was recorded in L-5, attributable to its lower height and gentler slope. A GIS-based FoS distribution map was generated using ArcGIS 10.4.1, depicting spatial variations in slope stability, with higher FoS values concentrated in the southern region and lower values in the eastern region. These findings offer critical insights for slope design and landslide prevention, highlighting the importance of integrating geophysical and geotechnical analyses to improve landslide hazard management and land-use planning.