The planning of mine drainage system at PT Perkasa Inakakerta, East Kutai Regency

Abstract

This research located in Beruang Block Kalimantan. The purpose of the mine drainage planning system is to control runoff water. Therefore, an excellent drainage system is needed without interfering with mining activities such as runoff water pollution, which could cause contamination in the surrounding area and outside the mining sites. Based on the analysis of rainfall data of 2009-2020, the precipitation plan was 341.67 mm/day; the concentration time was 2.37 h, the rain intensity was 41.06 mm/h, and repeated rain periods were 2-years. The extensive catchment area was 1.52 km2 because the runoff entering the sump was 44.38 m3/h. To prevent the water from entering the mining area, an open channel was made around the mine openings, and the water flows naturally into the sump. The water pumped into the settling pond with the pump type Allight HL 150MHD-IT at 50 m/s for 3-days with a single rain, resulting in total water volume of 17,556.5 m3/day. A trapezoidal shape was designed for a sump with dimensions of 3.96 m in length and width at the surface, 1.79 m length and width at the base, and 1.03 depth.