Challenging ground conditions and shaft completion delays during the development of the $5.3-billion underground project at the Oyu Tolgoi copper/gold mine, in Mongolia, have resulted in a nine-month schedule setback. Rio Tinto’s Turquoise Hill, which owns 66% of the mine, and the Mongolia government, which owns the remaining 34%, last week reported that sustainable production would now be achieved only in the third quarter of 2021, and not at the start of 2021 as previously forecast. In this picture, a dump truck operator walks past a Komatsu 930E dump truck in a maintenance bay at Oyu Tolgoi, which is located in the South Gobi desert. Rio Tinto took control of the orebody in 2012, 11 years after its discovery.