Kajian teknis area in pit dump di pit bendili prima, Departemen Bintang, PT Kaltim Prima Coal, Sangatta, Kalimantan Timur
P Pada kegiatan penambangan batubara di tambang terbuka, seperti PT Kaltim Prima Coal (PT KPC) praktik dumping atau pemindahan lapisan tanah penutup batubara harus diperhatikan dan direncanakan untuk menghindari terjadinya hambatan saat proses penambangan dan pembuangan overburden. Di Pit Bendili Prima, saat ini terdapat tiga out pit dump dengan jarak yang jauh dari lokasi penambangan (loading point) salah satunya di Panel Sawit menuju lokasi dumping point di ABVoid Dump, sehingga cycle time dump truck tinggi dan mempengaruhi jumlah dump truck. Untuk memperkecil cycle time dan mengurangi jumlah dump truck yang digunakan, maka dibuat desain dumping in pit di PR seam floor karena PR seam floor merupakan seam paling bawah di Pit Bendili Prima dan sudah selesai ditambang. Metode yang digunakan pada penelitian ini, yaitu metode observasi dan metode kuantitatif dengan membuat desain untuk dumping in pit di PR seam floor pada Bulan April 2023—Agustus 2023 yang dirancang menggunakan Software Minex 6.4.2 dengan memperhatikan dari sisi geometri dumping berdasarkan geometri lereng area rehab di PT KPC, yaitu lebar bench sebesar 30 m, tinggi bench sebesar 10 m, dan slope sebesar 1:1,5 (33,69â°). Selain itu, desain in pit dump PR seam floor juga memperhatikan dari sisi water management dengan diberikan kemiringan jalan sebagai catchment area pada area dumping in pit PR seam floor dan dari sisi geotech assessment, yaitu faktor keamanan (FS) ≥1,2, sehingga hasil FS deterministic (hasil tertinggi) dan FS mean (rata-rata) sebesar 1,3, sehingga pada desain in pit dump PR seam floor ini menghasilkan faktor keamanan ≥1,2 dan dinyatakan aman dari longsoran. Dengan adanya desain dumping in pit PR seam floor yang berkapasitas sebesar 4.963.997 bcm dan desain jalan angkut yang dirancang dari elevasi -150 hingga elevasi -20 ini dapat memperpendek jarak dari Panel Sawit menuju dumping area in pit dump PR seam floor dengan rata-rata menjadi 2.129 meter dan menurunkan cycle time menjadi 20,23 menit. Selain itu, jumlah alat angkut yang digunakan digger S602 dan digger S414 di Panel Sawit berkurang, yaitu untuk digger S602 pada Bulan April 2023—Juni 2023 dari 20—21 dump truck menjadi 7 dump truck, sedangkan untuk digger S414 pada Bulan Juli 2023 dan Agustus 2023 dari 13 dump truck menjadi 5—7 dump truck.
I In coal mining activities in open pit mines, such as PT Kaltim Prima Coal (PT KPC), the practice of dumping or removing coal overburden must be considered and planned to avoid obstacles during the mining process and overburden disposal. At the Bendili Prima Pit, currently there are three out pit dumps at a long distance from the mining location (loading point), one of which is at the Sawit Panel to the dumping point location at ABVoid Dump, so the dump truck cycle time is high and affects the number of dump trucks. To reduce cycle time and reduce the number of dump trucks used, a dumping in pit design was created on the PR seam floor because the PR seam floor is the bottom seam in the Bendili Prima Pit and has already been mined. The method used in this research is the observation method and quantitative method by creating a design for dumping in pit on the PR seam floor in April 2023—August 2023 which was designed using Minex 6.4.2 software by paying attention to the geometry of the dumping based on the slope geometry of the rehab area. at PT KPC, namely bench width of 30 m, bench height of 10 m, and slope of 1:1,5 (33,69â°). Apart from that, the PR seam floor in pit dump design also takes into account the water management side by providing a road slope as a catchment area in the PR seam floor in pit dumping area and from the geotech assessment side, namely the safety factor (FS) ≥1,2, so that the results The deterministic FS (highest result) and mean FS (average) are 1,3, so that the in pit dump PR seam floor design produces a safety factor of ≥1,2 and is declared safe from landslides. With the dumping in pit PR seam floor design with a capacity of 4.963.997 bcm and the haul road design which is designed from an elevation of -150 to an elevation of -20, this can shorten the distance from the Sawit Panels to the dumping area in the pit dump PR seam floor by an average of 2.129 meters and reduces the cycle time to 20,23 minutes. Apart from that, the number of transport equipment used by S602 diggers and S414 diggers in Sawit Panels has decreased, namely for S602 diggers in April 2023-June 2023 from 20—21 dump trucks to 7 dump trucks, while for S414 diggers in July 2023 and August 2023 from 13 dump trucks to 5—7 dump trucks.