Almost the entire open-pit mining process consists of the stages of drilling, blasting, sorting, hauling, and crushing of ore. Another crucial activity is maintaining slope stability and revegetating (reclaiming) land no longer used for mining with native plants.
At the Grasberg open-pit mine the primary equipment used are drills, shovels, and large trucks to extract materials. Materials referred to are classified as ore and overburden, depending on their economic value. Shovels dig up material from different areas in the open-pit mine, and load the material onto trucks to be hauled out of the open-pit mining area.
PT Freeport Indonesia employees at the Grasberg open-pit mine
Ore is placed into crushing machines and conveyed to an ore mill for processing. Overburden is placed in designated locations, or in OHS crushers on the HEAT road for placement in Lower Wanagon next to stackers.
The main facilities located near the open-pit mine include maintenance workshops, a limestone quarry and treatment plant, and other supporting facilities and offices.