Modeling and simulation of the dispersion of the ore tailings plume from the Fundão Dam (Mariana/MG), between the Rio Doce estuary and the Regência coast (ES), using Mohid Water software

Mathematical models demonstrate significant importance for simulations in water resources, and can be used to monitor tailings sediments from dam failures. The objective of this work was to simulate the dispersion of the tailings plume from the Fundão Dam failure in Mariana (MG), in the estuary between the Doce River and the coast of Regência (ES), using the MOHID WATER software. The influences of the atmospheric variables temperature and water-air interface were disregarded, and the wind speed was constant. River discharge is an important variable in the occurrence of chemical and biological processes in estuarine systems. Considering that turbulence influences the dynamics of the plume from the sea towards the river, together with the astronomical tide, it was possible to predict that even in the absence of any current the plume will continue to grow and will not reach a steady state, influenced by the ambient coastal current. Furthermore, the resuspension of sediments deposited by currents, meteorological tides or increased wind intensity may result in intermittent contamination, even if there is no further release of tailings sludge. Thus, the use of numerical models becomes relevant for this and future monitoring studies in the region.