Improving Gold Processing Technique to Reduce Health and Environmental Consequences

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1 Global Mercury Project Improving Gold Processing Technique to Reduce Health and Environmental Consequences (Central Kalimantan & North Sulawesi Indonesia) Budi Susilorini & Imelda Hutabarat Bandung,, 27 November 2006

2 GMP Background & Objectives Funded by GEF implemented by UNDP/UNIDO in six countries, including Indonesia. Main objective is to reduce global mercury pollution generated by artisanal mining activities. GMP teaches, assesses, and innovates best practices in technical know-how and governance (local to international) to assist small scale miners move towards cleaner technologies, sustainable livelihoods, and better health.

3 Outline Brief Summary on E & H Assessment North Sulawesi Project Site Historical Background, Problem Identification and GMP Implementation Central Kalimantan Project Site Historical Background, Problem Identification and GMP Implementation Mercury Magnitude and Policy & Governance Challenges

4 Global Mercury Project

5 Brief Summary on E&H Assessment : Biomonitoring and neuropsychology tests to diagnose Hg intoxication. Hg in blood, hair and urine was significantly higher in mineral processors, but especially amalgam burners. Hg concentration was found significantly high in fish live in amalgamation pond and downstream river.

6 Project Site Background Prior to 1998 : Hg amalgamation of gold only : Adoption of cyanidation practice; Initiated by US Dept Interior : Majority (80%) transitioned to cyanidation practice. BUT... Hg amalgamation continued to be used for quick cash in >50% of plants, prior to sending ore to CN plants. Issue : Hg amalgamation for wealth distribution.

7 Gold Processing With Cyanide Hg Add Activated Carbon (5% ORE Volume) to Adsorb Gold from Solution Carbon and Gold to Kana for Burning NaOH NaCN OXYGEN CN-Hg Tank ORE Hg Crusher, Ball Mill, Trommel ORE SOLUTION IN THE TANK: ph 10+, NaCN 200ppm, High Oxygen Content Hg Burning the Carbon Ash With Borax (2X Carbon Volume) Waste Solution to Tailings Pond N & CO2 Credit : Alfred Whitehouse GOLD River CN-Hg Decomposition of Cyanide by Sun and Rain

8 Problem Identification : NS Material : Operators use mercury contaminated tailings/concentrate in cyanide processing. Processing : Activated carbon absorbs both Au and Hg. 1. Reduced gold production. 2. Burning carbon loaded with Hg emits high concentrations of Hg.

9 Problem Identification : NS CN can easily dissolve Hg and tranport it to rivers to be dispersed over large areas. CN - Hg complexes in tailings may be more susceptible to methlyation. Challenge How do CN Hg complexes behave in the environment?

10 GMP Main Objectives in North Sulawesi 1. Improve current technique which is more economic and without further environmental degradation. Stop using Hg prior to cyanidation process. Concentrate ore using a sluice box prior to cyanidation. Improve cyanidation techniques and materials to increase gold recovery. BEST PRACTICES : ECONOMIC, HEALTH & ENVIRONMENTAL BENEFITS

11 GMP Main Objectives in North Sulawesi 2. Awareness campaign on mercury and cyanide hazard >>> encourage behavioral changes. Health hazards of cyanide and mercury. Health and safety on CN and Hg: storage, handling and waste management. Protect family and community health. Advice on consumption of low mercury fish species.

12 Project Site Background : CK Started in 1986 : Hg amalgamation of gold only.

13 Project Site Background : CK 35 gold shops along main road in Kereng Pangi. Chimney

14 Project Site Background : CK Rate and Amount 1989 : Primary forest cover is extensive 1999 : Extensive forest removal and vast area of mined sands

15 Project Site Background : CK Image Classification 1999 : Sand from Mining (cyan) 78 km sq, 18% ± 2%; Exposed Soil (brown) 64km sq, 15% ± 2%; Agriculture/ disturbed (grey) 117km sq, 27% ± 2% Sand from Mining (cyan) 102 km sq

16 GMP Main Objectives in Central Kalimantan 1. Improve current technique which is more economic and without further environmental degradation. Use of filtered fume hood and retort to burn amalgam. Optimize sluice box process by refining design and choosing good material components. Use Hg more efficiently. BEST PRACTICES : ECONOMIC, HEALTH & ENVIRONMENTAL BENEFITS

17 GMP Main Objectives in Central Kalimantan 2. Awareness campaign on mercury hazard >>> encourage behavioral changes. Health hazards of mercury. Health and safety on Hg: storage, handling and waste management. Protect family and community health. Advice on consumption of low mercury fish species and not to consume fish from amalgamation pond.

18 GMP Main Objectives in Central Kalimantan 3. Initiative on local policy and governance. Since years : Rate of Mining 8 km 2 /y Sediment Sluiced 119,574,000 t Gold recovered = 11.9 t Hg consumed since inception = 59.3 t Hg released by amalgam burning = 11.9 t Value of gold = $210 Million US Dollars $13 Million/year Issue : local economic devaluation.

19 Challenges To reduce mercury use in ASM activities by 50% in 10 years? Phase 1 : How to raise awareness and to change community within a short period? How to lift up the spirit of experiment among local partners, incl. miners, to find best solution? GMP is currently a pilot program of a community assistance model. Only a fraction of the global ASM has been touched. Progress could evaporate without further efforts. Further commitment is needed.

20 Acknowledgement Global Mercury Project team : Marcello Veiga, Rini Sulaiman, Randy Baker, Kevin Telmer and Cody Hopkins Yayasan Tambuhak Sinta : Bardolf Paul, Sumali Agrawal and team on the field Central Kalimantan Lestari : Sri Hardiyanti, Purnama Nainggolan and team on the field North Sulawesi Alfred Whitehouse (US Dept. of Interior) Asep Mulyana (USAID Env. Services Program) Dr. Lars Weitkaemper (University of Aachen, Germany) Department of Energy and Mineral Resources RI Government stakeholders in Central Kalimantan, Katingan District, North Sulawesi and Bolaangmongondow District CETEM University of Munich UNIDO CCOP

21 PROTECT OUR CHILDREN S FUTURE Thank You