27/11/2015
Analyses of the sediments of the Doce River and the tailings from the Fundão dam, operated by Samarco, show that none of the materials show an increase in the presence of metals which could contaminate the water.
The tests on the river sediments, carried out by the Brazilian Geological Service – Serviço Geológico do Brasil (CPRM) between November 14-18, show that there has been no increase in the presence of heavy metals in the water and the sediments compared to the data collected by CPRM itself in 2010. Analyses were made for 53 chemical elements and the results obtained were compared to the specifications of Resolution CONAMA 454/12 [CONAMA is the National Environment Council, a federal entity] which determines the classification of sediments in Brazilian sea and river waters. The results showed that the material sedimented in the river where the tailings plume passed – the stretch between Gesteira and Cachoeira Dantas – presented metal values below the guidelines for Level 2 sedimentation in fresh water. This means that the material sedimented in the Doce River represents no hazard to the environment.
The tailings from the Fundão dam were analyzed by SGS Geosol, a company specialized in environmental and geochemical soils analyses. Their report confirms that the material is not hazardous to people, based on the hazard classification of the material according to Brazilian standard ABNT 1004. The samples were collected at several points close to the site of the accident to assure better representativeness of the tailings contained in the dams. These tests showed that the tailings are not toxic and do not present any hazard to human health, as they do not generate water contaminants, even when exposed to rain. In addition, as the tailings are within all acceptable limits for metals present (except for iron and manganese, characteristic of local geology), one can conclude that the material does not contribute to the increase of other metals in the water.
