PERANCANGAN SARANA PENYALIRAN PADA TIMBUNAN BATUAN PENUTUP TAMBANG TERBUKA BATUBARA PT XYZ

• Main Author: Firmansyah Husaeni, Adithiya
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/86464
• Institution: Institut Teknologi Bandung

PT XYZ is an open-pit coal mining company operating in Sangatta Subdistrict, Kutai Timur Regency, East Kalimantan Province. One of the mining activities involves overburden dumping in open areas, making the open-pit mine drainage system crucial in reducing environmental risks and ensuring smooth mining operations. Managing rainwater runoff in the dump area is the primary challenge faced. The designed drainage system includes open channels, drop structures, culverts, bench drainage, perimeter drainage, and road ditches. The drainage system design starts with analyzing rainfall data from the C-North station over a 10-year period (2013–2022) using the Log Pearson III distribution, resulting in a rainfall value of 133.3 mm, with a rainfall intensity of 46.21 mm/hour for a 20-year return period. Additionally, a catchment area of 230 hectares was mapped, and the runoff discharge was calculated using the Rational Method. The study ignores geotechnical, economic, water quality, evaporation, and infiltration aspects. The drainage system design is tailored to accommodate the runoff discharge capacity. The open channels are categorized into four types, with trapezoidal shapes and dimensions of bottom width × top width × height as follows: (1 × 2.5 × 1.4) m; (0.7 × 1.2 × 1.4) m; (1 × 3 × 1.7) m; and (0.5 × 0.9 × 1.2) m, to be used for the main channel, bench drainage, perimeter drainage, and road ditches, respectively. Four drop structures are designed for the main channel to address potential erosion along the channel walls. Culverts are designed at lengths of 50 m, 60 m, and 63 m, with dimensions of 1 m for 3 barrels, 1 m for 2 barrels, and 0.5 m for 2 barrels.