The Minas Gerais state in Brazil has one of the highest concentration of iron mines per square kilometer in the world. These mines, upon receiving the ore from the pits and processing it through the plant, produce a large quantity of solid waste (known as mine tailings) that is deposited in sedimentation ponds inside the processing plant. Once these mining ponds are filled with sediment, the latter must be transported to a larger embankment area for final disposal. This was the case of the mine, where the situation was reaching critical levels.
One of the main concerns here, was keeping the costs at a minimum for the mine, so there should be as little steps in the process as possible.