Pre-operational environmental survey at the uranium mine and mill site, Poços de Caldas, Minas Gerais, Brazil

The first Brazilian uranium mine and mill are located on the Pocos de Caldas plateau, in the Central State of Minas Gerais. The pre-operational environmental survey was carried out over a period of two years by the Brazilian Nuclear Energy Commission (CNEN), through the Instituto de Radioprotecão e Dosimetria (IRD). The selection of the materials to be monitored, the sampling points and the radionuclides to be analysed were based on critical parameters taking into account the meteorological and hydrological characteristics of the site as well as land use. The results obtained are sufficient to characterize the environmental background of the area, and will allow an assessment of the environmental impact due to the operation of the facility and an evaluation of the adequacy of the effluent emission control measures. In relation to their contribution to the population dose, the results indicated that 226Ra and 210Pb will be the important radionuclides.