The Moab uranium mill tailings pile is a uranium mill waste pond situated alongside the Colorado River, currently under the control of the U.S. Department of Energy. Locals refer to it as the Moab Tailings Pile. In 1952 Charlie Steen found the largest uranium deposit in the United States near Moab, Utah. The uranium was processed by the Uranium Reduction Company and the waste slurry was stored in an unlined pond adjacent to the river.