 In October 2009, Arch acquired Rio Tinto's Jacobs Ranch mine and blended it with Black Thunder Coal Mine in the southern Powder River Basin of Wyoming, creating the single largest coal mining complex in the world.In November 2009, Arch acquired the rights to mine 731 million tons of Otter Creek coal reserves in the northern Powder River Basin of Montana.On June 15, 2011, Arch acquired International Coal Group (ICG) and cemented its place as a top five global coal supplier and a top 10 metallurgical coal producer and marketer.