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Mercury Use Reduction and Land Reclamation in the Tapajos Region, Brazil by Rodolfo N. Sousa/ Marcello Veiga. CASM Conference - Brasilia Oct/2008. Global Mercury Project. A United Nations (GEF/UNIDO) program created in 2002 aiming to: Reduce Hg pollution caused by ASM
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Mercury Use Reduction and Land Reclamation in the Tapajos Region, Brazilby Rodolfo N. Sousa/ Marcello Veiga CASM Conference - Brasilia Oct/2008
Global Mercury Project A United Nations (GEF/UNIDO) program created in 2002 aiming to: Reduce Hg pollution caused by ASM Introduce and disseminate good practices Train miners and develop community awareness
Global Mercury Project In collaboration with UBC Dept of Mining Engineering Senegal Guinea Sudan Laos Venezuela Indonesia Suriname Cambodia Ghana Colombia Tanzania Brazil Ecuador Mozambique Zimbabwe
The Amazon scenario • Area of 5,5 million km2 in 9 countries, of which 72% (4 million km2) is located in Brazil • The Brazilian Amazon has lost 18% of its original area or 650,000 km2(larger than France) • The Amazon looses 0.27% - 0.65% of its area every year or 24,000 km2 (the size of Belgium) • Deforestation in the Amazon started in 1970’s
Deforestation in the Amazon Garimpo Canaan 4 million km2 18% deforestation Brasilia
1980’s: Serra Pelada, the largest concentration of miners in the world
Magnitude of ASM in the Tapajós 40,000 miners 500 to 2,000 mining sites 400 air strips 5.8 tonnes/year of gold 10-12 tonnes/year of Hg for amalgamation
Socio-economic aspects Most miners do not have mining permit or environmental license; Education is very limited; Gold is the main source of revenue; A miner consumes 40g Hg/month, produces 18g Au/month, and income of US$350/month Hg costs US$200/kg. Au is sold by US$25/g.
Environmental and Health Aspects Mercury contamination: soil, air, biota, fish, miners; High level of Hg in fish: 4 to 5ppm, cases of 22ppm, whereas guideline is 0.5ppm; Mercury vapor: amalgamation without retorts and gold shops without proper filters; Water contamination: tailings disposed directly into the rivers (siltation exacerbates bioaccumulation), Hg, CN, oil, sewage, garbage
Environmental and Health Aspects Drinking water: water consumed directly from local streams, no latrines or proper waste disposal, high level of malaria and parasitosis Deforestation: pits are open in critical areas along the streams and rivers. Very low level of land reclamation
Tapajós River Mobility of Hg-contaminated Tailings Tailings take >4 t/a of Hg to other areas Hg is methylated and bioaccumalted downstream 200 km Hg-rich Tailings from gold miners Crepori River Source: Telmer et al. (2006)
ASM in the Tapajos In 2006, Brazil produced 40 tonnes of gold, of which 5.2 tonnes were produced by ASM (estimated 3 tonnes in the Tapajos) 300 – 600 pits, each with a volume greater than 10,000m3 are opened annually 3 to 6,000,000 tonnes/a of tailings into the rivers Area disturbed by excavation of pits by hydraulic monitors in the Tapajos is around 12,000 ha
Scenario of Artisanal Mining an GMP’s approach • Large number of people involved • Low level of formal education and basic infra structure • Most miners are informal / ASM is a marginal activity • ASM causes more environmental impact than most large companies but they are not in the media • Very low investment for ASM on the ground • UNIDO / GMP acknowledge that: • The project is a very important initiative, but very small in scale when compared with the scale of the problem. • Education and prevention are keywords for the success of the project
General statements about training programs Training is a step to reach a result, but it is not a result in itself; Number of trainees and program content are important information, but are not the result itself; Training people does not imply that they have learned lessons; Learning lessons does not imply that they will implement what they have learned; But, The real result of training occurs when the trainees incorporate the lessons learned to their daily routine
Objectives & effectiveness evaluation 5 MAIN OBJECTIVES: Promote legalization of mines Improvement of Gold Production Protection of Forest and Water Reduction of Hg Use Improve Health and Sanitation Evaluation of “garimpos” prior to the training and 3 to 4 months after training
Distribution of retorts to disseminate the culture of protection against mercury vapour during the amalgam burning
Kitchen bowl retort (homemade solution) Hg condenses on the glass bowl Wet sand to seal Hg vapour
Fume hoods: developed local supplier, Filters installed in local gold shops
Vision General structure of the Action Plan Mission General Objectives Goals Performance Indicators Monitoring processes and results
Reclamation in ASM Complex and costly reclamation methods are not effective in ASM. Simplicity is mandatory. For example, soil salvation is an ideal technique but complex for ASM Cases of rehabilitation are “volunteer initiatives”, as non-compliance is prevalent