The actions taken by Samarco, in addition to a
rainfall reduction, have contributed to a significant decline in the turbidity
levels in recent weeks, as the water quality monitoring indicates. In early
April, the values were below the limit of 100 NTU established by Resolution 357
of the Environmental National Council (CONAMA), along the entire stretch
between Governador Valadares (MG) and the river mouth in Regencia (ES).The same turbidity reduction trend is observed in the
stretch of the Doce River Basin between the Fundão valley and Governador
Valadares, where the lowest turbidity levels yet since the dam burst are being
recorded. The data are collected from Samarco’s water monitoring points
disposed along the rivers and are periodically reported to the competent
bodies.
These results are due to the various actions that have
been carried out by Samarco to contain the entrainment of sediment in the water
courses of the Doce River watershed. These actions include the revegetation of
the river banks which have been impacted by the tailings, the construction of
sediment containment dikes, and the treatment of water in these dikes.