For more than three decades, Barr has been helping a Minnesota iron mining company with design and maintenance of its tailings basins and dams. The client wanted to replace a rock weir in its tailings basin that was difficult to raise, required constant maintenance, and exhibited a high risk of failure. Barr designed a reinforced-concrete spillway featuring a series of concrete steps to dissipate the energy during transfer from one tailings cell to the next at lower elevation. Designed to be raised more than 50 feet during operations by increasing the height of the abutment walls and concrete steps, the spillway can accommodate additional tailings storage for the planned life of the mine.