Oyu Tolgoi consists of deposits containing copper, gold, and silver. The deposits extend over 12 kilometers from the Hugo Dummett North Zone in the north, through the adjacent Hugo Dummett South Zone, to the Oyut deposit, and then to the Heruga deposit in the south. Underground deposits have been key to Oyu Tolgoi’s overall profitability as the mineral grade is much higher than that of open pit mines. More than 80% of the total value of Oyu Tolgoi is located deep underground. It is one of the best copper-gold orebodies in the world. The Oyu Tolgoi Underground Project is a significant development to access and mine the Hugo North Uplift ore body. The average copper grade is expected to be 1.66% over the life of the mine.
The depth and fragmentation of the ore body make it both geotechnically and economically suitable for block-caving mining – which involves digging below the ore body and collecting falling ore. Underground works include sinking a total of 6.1km over five shafts and digging 203km of tunnels at a depth of 1.3km underground. Other supporting infrastructure includes crushing and material handling as well as surface facilities. At present, we are providing AHU ventilation facilities for the underground ventilation project in 2023 to help them better mine and construct and ensure the covert activities and safety of workers.