RESUMO
Iron ore tailings are stored in large dams and pose risks to the environment around the world. In Brazil, the rupture of these dams has become frequent and has generated environmental and social concern. Rare earth elements are good tracers of sediment sources and our results indicated chronic contamination of the seabed sediment from the marine region affected by the Fundão Dam tailings since 2015, including areas of environmental protection. This research, carried out between November 2018 and September 2021, with a database of 575 samples, showed a greater amount of contaminated material in the marine region adjacent to the Doce River mouth. Although data suggest prior mining contamination of the Doce River basin, the Fundão episode was an empirical and massive example of the environmental damage caused by these human activities over the centuries, showing that the impact remains in the shallow marine environments for years. Integr Environ Assess Manag 2024;20:179-188. © 2023 SETAC.
Os rejeitos de minério de ferro são armazenados em grandes barragens que trazem riscos ao meio ambiente em todo o mundo. No Brasil, o rompimento dessas barragens tem se tornado frequente e gerado preocupação ambiental e social. Elementos terras raras são bons marcadores de fontes sedimentares e nossos resultados indicaram uma contaminação crônica da região marinha afetada pelos rejeitos da barragem de Fundão, incluindo áreas de proteção ambiental. Esta pesquisa teve com 575 amostras analisadas entre os meses de novembro de 2018 e outubro de 2021, com a região marinha adjacente a foz do Rio Doce apresentando o maior grau de impacto. Embora os dados ressaltem a contaminação histórica da mineração na bacia do Rio Doce, o episódio do Fundão foi um exemplo empírico e massivo dos danos ambientais causados por essas atividades ao longo dos séculos, mostrando que o impacto permanece nos ambientes marinhos rasos por anos. Integr Environ Assess Manag 2024;20:179-188.
Assuntos
Monitoramento Ambiental , Poluentes Químicos da Água , Humanos , Brasil , Rios , Mineração , Ferro , Poluentes Químicos da Água/análiseRESUMO
The Brazilian Nuclear Energy Agency (CNEN) is responsible for any radioactive waste storage and disposal in the country. The storage of radioactive waste is carried out in the facilities under CNEN regulation and its disposal is operated, managed and controlled by the CNEN. Oil NORM (Naturally Occurring Radioactive Materials) in this article refers to waste coming from oil exploitation. Oil NORM has called much attention during the last decades, mostly because it is not possible to determine its primary source due to the actual absence of a regulatory control mechanism. There is no efficient regulatory tool which allows determining the origin of such NORM wastes even among those facilities under regulatory control. This fact may encourage non-authorized radioactive material transportation, smuggling and terrorism. The aim of this project is to provide a geochemical signature for oil NORM waste using its naturally occurring isotopic composition to identify its origin. The here proposed method is the modeling of radioisotopes normally present in oil pipe contamination such as 228Ac, 214Bi and 214Pb analyzed by gamma spectrometry. The specific activities of elements from different decay series are plotted in a scatter diagram. This method was successfully tested with gamma spectrometry analyses of oil sludge NORM samples from four different sources obtained from Petrobras reports for the Campos Basin/Brazil.