URANIUM MINING IMPACTS ON WATER RESOURCES IN BRAZIL

Uranium mining and milling activities started operations in Brazil during the 80´s. The first production Center was deployed in Poços de Caldas (CIPC) State of Minas Gerais. The mine was exhausted in 1997, after has produced only 1200 t of U3O8. The second uranium plant began the operations in Caetité (URA), Bahia State, since 1999 and keeps operations until now with an annual U3O8 production of up to 400 t. The company plans to double this mark in Caetité production center with the exploration of another uranium deposits and initiate underground operations of current open-pit mine. Simultaneously, they are seeking a license for a third plant in the State of Ceará that could produce the double of foreseen capacity in URA. This scenery drives to some issues related to the impact of uranium production on water resources of the respective watersheds. The CIPC plant is a closing mine site, which requires permanent treatment of the company due to the fact their sources of pollutants are subject to the occurrence of Acid Mine Drainage (AMD). The URA plant is located in a semi-arid region of Brazil. The extraction of uranium from the ore is achieved by means of a Heap-Leach process, which has low water demand supplied by a network of wells and from a dam, but can contribute to change the groundwater quality and in some cases the extinguishing of wells was observed. An overall assessment of these impacts in national level could produce some lessons that we must take advantage for the ongoing project of Santa Quitéria or even in future sites.