Evaluasi Pelaksanaan Pemboran untuk Memenuhi Target Produksi pada Penambangan Quarry di PT. Semen Padang, Bukit Karang Putih, Indarung, Kecamatan Lubuk Kilangan, Kota Padang

PT Semen Padang is a company which engages in cement production. PT Semen Padang supplies the basic material of cement production from two areas. Firstly, chalk stone as basic material is supplied from Bukit Karang Putih Mining. Secondly, Silika and loam are supplied from Bukit Ngalau Mining as KP of PT Semen Padang.PT Semen Padang applies a system of surface mining by open pit method where is done land opening and land excavation of the surface of earth. Themining of chalk stone is done by drilling and explosion which has a purpose tobreak in the chalk stone from the basement. Based on the product of explosion anddrilling system, the real production can be known in a day.For stone drilling activity that will be explosed, PT Semen Padang usesd rill master Ingersoll Rand 03 by benching system. Target of chalk stone production on October 2012 was 25.000 ton. Meanwhile, real production that had gotten by this Company was only 18.353 ton. It happened because of several factors such as, weather bad condition, drill tool demaged and etc. After doing the analysis on Drill Master 30 Ingersoll Rand that is used indrilling activity for hole explosion of drilling area Chalk Stone at Bukit Karang Putih, there are several reparations that should be done and influence towardd rilling process such as work efficiency, equipment avaibility, and the geometry of explosion. 1) Work efficiency is increased from 60,71% to 76,19%. 2)Equipment avaibility is increased from 85% to 95%. 3) Repairing the explosion geometry that uses Drill master 30 Ingesoll Rand with burden 4,5m, spacy 4,5m,deep of hole explosion 7m, height of bench 7m, steammning 3,15m and subdrilling 1,35m.