SISTEM PENYALIRAN TAMBANG PIT AB EKS PADA PT. ANDALAN MINING JOBSITE KALTIM PRIMA COAL SANGATTA KALIMANTAN TIMUR

Abstract

The rains in the mining industry may affect mining operations, required a form optimal effort for handling incoming water to the mining area through a system of drainage mine engineering studies. The purpose of this study was to determine drainage system used specifically for the process of removing water that was at the sites. Calculation of rainfall plan determined using gumbel distribution, the calculation of rainfall during the two-year plan is 86.88 mm/day. Based on the results obtained when the concentration of 3.52 hours, rainfall intensity 30.44 mm/hours, flow coefficient of 0.75 and 5.26 km2 catchment area so that the results obtained discharge runoff into the sump is 120,168 m3/hours and volume sump 422,991.36 m3. Water in the sump is pumped out of the pit by using three pumps multiflo 420 with a capacity of 1 pump is 828 m3/hours. To remove the water in the sump for 8 days 12 hours to see the rain during the first time.