Design, supply, construction of all facilities to blind sink and concrete line Shaft #3 to a depth of 1,148 m and to a finished diameter of 10 m and Shaft #4 to a depth of 1,149 m and to a finished diameter of 11 m. Project holds national heave single lift record. Both shafts are part of Oyu Tolgoi Underground expansion, Rio Tinto to be used as ventilation shafts.