15/01/2016

After the removal of the organic material from the Doce River, a task which has been ongoing since November 10, Samarco is dedicating efforts to recovering the color and clarity of the river waters along the entire section impacted by the accident with the Fundão dam in Mariana.

Studies and monitoring performed by the Company and specialists contractors show that it is possible to recover the original parameters. Their expectation is that the work will be fully concluded within at the most three years. Samarco's commitment, however, is to go beyond and make the Doce River waters attain even higher quality levels than the ones presented prior to the accident.

Work in progress

The rehabilitation work also includes other measures which are being carried out simultaneously in different areas along the river and its tributaries.

Cleaning of the Candonga Reservoir - the Company starts this week the dredging of the Risoleta Neves hydropower plant, which is fed by the Candonga dam. The first phase of the work should take about 120 days, and involves the cleaning of 400 linear meters at the site.

The cleaning work in the surrounding areas, however, involving the cities of Santa Cruz do Escalvado and Rio Doce, already started on November 10 and is at an advanced stage of completion.

Revegetation - since the 10 of December, Samarco has been working on the emergency and temporary revegetation of the banks of the Gualaxo, Carmo and Doce rivers, between the city of Mariana and the Risoleta Neves plant.

The planting approach involves a mix of native plants with fast germination, so that the banks will be exposed for as little time as possible, and the entrainment of sediments will be minimized. The forecast is for the work to be concluded within 90 days.

Sonar - another action in progress is the mapping of aquatic life in the Doce River using sonar. The diagnostic, performed by a specialized consultancy firm, confirmed the presence of shoals of fish along the water ways. The studies in progress, using the data collected by the equipment, will serve as input for the repopulation project of river species.

Next steps

The actions and tasks of the next phases of the recovery of the color and clarity of the Doce River waters will be defined on the basis of a series of studies, from the characterization of materials to quality analyses of water, fauna and flora. The forecast is that already in the next rainy season the results of the initial actions will show the first major signs of progress in this area.

Samarco Mineração SA issued this content on 2016-01-15 and is solely responsible for the information contained herein. Distributed by Public, unedited and unaltered, on 2016-01-16 00:47:01 UTC

Original Document: http://www.samarco.com/en/2016/01/15/samarco-dedica-se-a-recuperacao-da-cor-e-turbidez-do-rio-doce/