Release of Uranium by an Ore Treatment Unit at Caldas, MG, Brazil

Wagner de S. Pereira, Alphonse Kelecom, Juliana R. de S. Pereira, Delcy de A. Py Júnior

Interdisciplinary under Graduation in Science and Technology, Universidade Federal de Alfenas, Po?os de Caldas, Brazil.
Laboratory of Radiobiology and Radiometry Pedro Lopes dos Santos (LARARA-PLS), Group of Environmental Themes Assessment (GETA), Universidade Federal Fluminense (UFF), Niterói, Brazil.
Multidisciplinary Group of Radioprotection (GMR), Servi?o de Radioprote??o, Unidade de Tratamento de Minério, Indústrias Nu- cleares do Brasil, Caldas, Brazil.
Multidisciplinary Group of Radioprotection (GMR), Servi?o de Radioprote??o, Unidade de Tratamento de Minério, Indústrias Nu- cleares do Brasil, Caldas, Brazil; Laboratory of Radiobiology and Radiometry Pedro Lopes dos Santos (LARARA-PLS), Group of Environmental Themes Assessment (GETA), Universidade Federal Fluminense (UFF), Niterói, Brazil.

DOI: 10.4236/jep.2013.46066                

Abstract

This study aims to assess the behavior of the release of U_nat (i.e. uranium isotopes in natural relative abundance) from the release of water treated by the Ore Treatment Unit (UTM) in Caldas, state of Minas Gerais, Brazil, during the years 1999 to 2009. During this period, the unit showed no industrial activity, except between 2004 and 2005, when UTM operated 400 tons of monazite in a process to obtain rare earths. U_nat was analyzed by spectrophotometry once per week in the effluent waters at sampling point 014. Two fractions were considered for analysis: the soluble one (that passes through a 0.45 μm filter) and the particulate one (retained on a 0.45 μm filter). Statistical analyses were performed: the “Z” test and Pearson’s r² correlation index. The values for the soluble fraction were consistently lower than those of the particulate fraction and no statistically significant correlation was observed between the soluble and particulate fractions. However, the particulate and the total fractions (the sum of soluble and particulate) strongly correlated.

Keywords

Uranium; Ore Treatment Unit; Caldas; Radionuclide Monitoring

Conflicts of Interest

The authors declare no conflicts of interest.

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