Abstract
Berau Basin, a sub-basin of Tarakan Basin, had been developed during Eocene to Miocene period. Rocks in Berau Basin consist of sedimentary, volcanic and igneous rocks aged from Pre-tertiary until Quaternary epoch. The youngest identified rock formation was alluvial deposit consists of mud, silt, sand, gravel and swamp with brown to dark color. This youngest rock formation is relatively weak geological condition and can cause problems in the coal mining operation. PT Berau Coal as one of the coal mining companies in Berau Basin area had experienced some problems related to the occurrence of alluvial deposit. A large failure has occurred at one of its out pit dumping area which lies over the swamp material. The failure caused a higher operating cost since it made that the distance for waste rock dumping became to be farther than the designated area. Therefore, in order to prevent similar failure occurring at dumping area which lies above swamp material, an improvement of dumping site stability on weak geological condition has to be needed. The proposed method for improving the stability of out pit dumping area in weak geological condition is to construct the compacted layer of waste rock before the out pit dumping area construction. Based on experimental results, a minimum of 40 kPa pressure is needed to give a proper compaction to the waste rock. The result of numerical analysis by Finite Element Method (FEM) shows that construction of compacted layer on the base of out pit dumping area can improve its stability.
Highlights
PT Berau Coal is one of the Indonesian coal mining companies located in Berau Regency, East Kalimantan
Numerical analysis using Finite Element Method (FEM) was carried out to simulate the stability of dumping area by using properties obtained from the laboratory test and geometry of the failure out pit dump
The cause of out pit dumping area failure near Pit East, Lati Area, PT Berau Coal was the existence of swamp material at the base of out pit dumping area
Summary
PT Berau Coal is one of the Indonesian coal mining companies located in Berau Regency, East Kalimantan. One of its mining operations is located in Lati area (Figure 1(a)). Due to the geometry of coal deposit, the mining activity in Lati area was divided into 5 pits which are Pit West, East, T, Others and North. The presence of the youngest rock formation in Lati area, which is alluvial deposit, makes several problems to mining operation especially the waste rock dumping operation due to its weak strength characteristics. Waste rock dumping operation plays an important role in mining activities [3]. This operation needs to be conducted effectively in order to reduce the operating cost. The improvement of dumping area stability by using compacted layer of waste rock will be discussed
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
