This one "district" in Wyoming has about half the entire coal reserves in the US.
The Powder River Basin coal mining district in Wyoming is regarded as the most prolific coal mining model in the industry to date. Some 14 active coal mines extract more than 400 million tons annually, and two railroads deliver that coal to some 37 states.
The district is said to have a capacity upwards of 500 million tons annually, which would amount to half the United States coal supply.