Sampling and Homogenization Studies of Uranium Mining Waste Rocks Using Normal and Large-Sample INAA

Abstract

Uranium mining activities at Pocos de Caldas plateau, Brazil, generated huge amounts of sulfidic waste rocks which were dumped into piles around the mine pit, requiring control measures to minimize the environmental impact. In this work, the sampling and the homogenization of these waste rocks are studied and their elemental analysis by instrumental neutron activation analysis (INAA) using normal (about 200 mg) and large (about 2 kg) samples. The results obtained allowed us to conclude that the waste rocks are extremely heterogeneous requiring even larger quantities of sample for its characterization.