Implementing programs to improve gold recovery and reduce environmental impacts by artisanal gold mining in Brazil

• Main Authors: Sousa, Rodolfo N., Veiga, Marcello M. (Marcello Mariz)
• Language: English
• Published: 2009
• Online Access: http://hdl.handle.net/2429/8466

Artisanal and small-scale gold mining (ASM) is the largest source of mercury release into the environment from intentional use sources. One of the largest sites is located in the Tapajos River Basin region, in the Brazilian Amazon. In 2002 GEF/UNDP/UNIDO (United Nations Industrial Development Organization) implemented the GMP (Global Mercury Project) in Brazil, aiming at the reduction of mercury emissions through the introduction of simple technologies, as well as the implementation of health and environmental awareness. The program trained 4,200 miners in 115 mining sites in Brazil. The main highlights are the improvement of gold concentration by the use of “zig-zag” sluice boxes with better carpets, demonstration of closed-circuit amalgamation conducted in excavated lined pools, introduction of an electrolytic mercury activation process, introduction home-made retorts, refilling of old pits with tailings as a step to reclaim degraded areas. The original survey has shown 64.6% of miners in selected areas refilling old pits, 58.3% retaining sediments, 12.5% recycling mercury, 35.4% conducting amalgamation in lined pools, 43.8% using latrines, 20.8% drinking filtered water and 43.8% collecting their garbage. These numbers escalated to 100.0, 91.7, 91.7, 75.0, 100.0, 81.3 and 100.0% respectively, 90 days after the GMP training program and awareness campaign.