Mine Landslide Management Sustainability Model in Kutai Kartanegara Regency, East Kalimantan, Indonesia

Abstract

This research aims to identify the geological and lithological structures of mine land, determine the slope stability of the land, and determine the sustainability of landslide management in Kutai Kartanegara Regency, East Kalimantan, Indonesia. This present research was conducted in Samboja and Sebulu sub-districts, Kutai Kartanegara Regency, East Kalimantan, Indonesia. Data collection concerning the geological structure, lithology, and sustainability of coal mine landslides was carried out. Rock data, such as its physical and mechanical properties, were taken from complete coring drilled and then analyzed in a geomechanics laboratory. This procedure was carried out in three locations, with the first and second samples collected in the Kampungbaru Formation representing the youngest formation. In addition, the third taken in the Pulubalang Formation represents the oldest coal-bearing formation. The data relating to the avalanche condition were collected through surveys, interviews, and filling out questionnaires using a purposive sampling method. The respondents were 13 mining engineering heads from various mine sites in Kutai Kartanegara Regency, three mining environmental experts, and four academics. The results showed that of the 50-joint data, those with potential positions for landslides were located at N333°E/61° and N110°E/74°. The most dominant lithology in the study area was claystone, followed successively by sandstone, siltstone, and shale, with a specific gravity between 2.55 and 2.66. The dominant claystone indicated a relatively prone area. Meanwhile, the strength of the mechanical properties of the rock (direct shear) cohesion ranged from 17.80 and 174.53 kPa, with shear angles ranging from 10.88° to 42.01°. Based on the design of the slope stability in the three locations, this study demonstrated the maximum slope angle ranging from 29° to 37°, a height of 50.17 to 70.16 meters, a single slope height of 10 meters with an angle ranged from 32° to 44°, and a factor of safety (FOS) ranging from 1.326 to 1.452 with stable conditions. Multi-dimensional scaling (MDS) simulation results of the sustainability status comprised of a total of 49 attributes derived from five dimensions, namely ecological, economic, social, law, institutional and technological, demonstrated a score fell of 50.01. Furthermore, to increase the sustainability score, this study identified some sensitive factors as follows: condition of the slope of the mine slope, MSME business of residents, role of NGOs in mine landslides, concern of pit supervisory personnel for mine landslides, and mastery of mine landslide technology. Hence, the projection sustainability score increased to 82.00, which was achieved in the good category.