Sampling and homogenization studies of uranium mining waste rocks using normal and large-sample INAA

Uranium mining activities at Pocos de Caldas plateau, Brazil. generated hug e amounts of sulfidic waste rocks which were dumped into piles around the m ine pit, requiring control measures to minimize the environmental impact. I n this work, the sampling and the homogenization of these waste rocks are s tudied and their elemental analysis by instrumental neutron activation anal ysis (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 character ization.