Landslide susceptibility and structural stability of open dump site in urban environment

Landfill Stability Risk Assessment study (LFSRA) of Landfill carried out by integrating elevation data and geophysical analysis. The geophysical data involving 2D Electrical Resistivity Imaging (2D ERT) and Seismic methods (Refraction) and Topographic information were collected on parts of the dumpsite in relation to the environment.Slope analysis of the topographic data has shown that the slope gradient of the adjoining area ranges from 0.06 (≈ 3.3 ° or very gentle slope) to 0.8 (≈ 38.6 ° or very steep slope) of which slope gradient above 15° have high potential for landslides and greater than 35° have high potential for imminent collapse. The 2D resistivity data have shown low resistivity zones within the shallow subsurface region (3 to 12m) which are leachate/water saturated regions and are therefore susceptible to mass wasting. Similarly, the subsurface is represented by low seismic velocity within the depth of 7 to 15m which is consequent of very loose to weak subsurface regions with possibility of mass wasting. In general, the inherent loose nature of the landfill will aggravate the potential of landslide.Nevertheless, the regions with high potential landslide are relatively far from surrounding structures and the proximal parts are bounded by topographic depression that can serve as buffer in the event of eventual landslide or collapse.