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Increasing capacity for mercury-free ASGM through provision of technical assistance, technology transfer and support for formalization.

The project’s core strategy for mercury reduction/elimination is to facilitate the adoption of alternative processing methods which utilize less or preferably no mercury. The project will assist local, provincial and national stakeholders and beneficiaries in Indonesia in implementing mercury reduction/elimination interventions by providing technical assistance, while tracking changes in mercury use and mercury practices (which in turn provides insights in emission and exposure reduction) at ASGM sites benefitting from the project.

Initially the project will focus most of its support on the most formalized and organized mining groups holding legal concessions (with a priority for women-led mining groups or mining groups containing female members), however the project will also evaluate the potential for project support to assist other mining groups in their formalization processes. Ultimately the goal of the project is to help these mining groups to reach a stage of formalization in which they have access to finance and clean technologies. 

Formalization: In combination with project Component 1 (Improve regional government capacity and improve the enabling regulatory environment to make formalization more accessible) and Project Component 2 (Assist miners in accessing funding for mercury-free ASGM), Project Component 3 will complement the formalization process of ASGM miners supported by the project. 

Reducing mercury by improving gold processing practices: Key mining sites used by mining groups supported by the project will be characterized in terms of ore and production means, and will undergo a general needs assessment. Ore assays will be conducted in accredited metallurgy labs, but will be supplemented with practical on-site liberation tests and training events in the field to give miners the opportunity to observe results first hand and learn how to obtain such results themselves. These results will then be used to help the miners/mining groups design processing strategies and economic models to convert to mercury free practices. 

Training and demonstration activities to support miners/mining groups in converting to mercury-free practices require pilot training plants and facilities that are available in or close to key project sites and as early in the project as possible. 

In addition, the project will provide technical assistance to the establishment of at least one (1) mercury-free ore processing training plant in one (1) project location (with funding provided by a financial mechanism or non-project financier). In each of the other 5 project locations, small mobile plants composed of lab scale processing tools, will be used to teach artisanal grade control and exploration (using only simple mills and gravity concentration tools to assess the ore grades, prove presence of gold in exploration samples from prospective mine locations, and determine optimal grain size of milled ore for maximal gold liberation). The small mobile plants will also help miners make economic calculations and comparisons of mercury versus non-mercury processing methods. The core of these mobile plants is a high capacity (~2 tonnes per hour) concentration tool that can concentrate small amounts in demonstrations and ore analysis, but can also be directly incorporated into a full-scale plant to directly eliminate mercury. Similar to the large pilot training plant, at the end of the project, the ownership of the mobile plants will be transferred from credible lenders to mining cooperatives or community groups in a lease-to-own-programme so that the miners can continue mercury-free processing and train new miners in its use. The lease payments would accrue to a revolving fund managed by the lender out of which new mercury free instalations could be financed.

The project will train a total of 1,200 miners through training activities centered around the large pilot training plant and the 5 smaller mobile training plants. These training activities will foster linkages among miner, financier, equipment manufacturer, distributor, regulator, and community participants in a way that each person trained can develop an economic model of mercury free practices according local ores they have tested themselves. 

Tailings Management: Mercury containing legacy tailings present a long term environmental and human health risk from mercury releases, acid generation and potential storage failures. Yet such tailings can also be a resource as they can contain considerable concentrations of gold. The project will therefore undertake a feasibility study to assess the potential for the removal of mercury from tailings by large-scale mining companies, who operate facilities that could be adapted to recover mercury from ASGM mine wastes (for instance, many industrial mines produce mercury as a byproduct, so they already have industrial retorts and environmental management facilities. ASGM tailings processing could extend the useful life of large scale plants considerably). Based on the outcomes of this feasibility study, partnerships with large-scale mining companies could potentially be developed and lead to a reduction in environmental risks from unsound tailings disposal (by trucking away tailings and ultimately extracting remaining gold concentrations), and improve relationships between ASGM miners and large mining cooperatives.

Pilot Remediation: Finally, the project will also undertake one small scale mercury removal pilot project to recover residual gold and mercury from orphaned illegal alluvial mine sites, with extreme precautions for the prevention of remobilization of mercury in fugitive suspended sediments. Several centrifuges and shaker tables in series will progressively remove metals from the tailings, and a de-watering spiral will pile the residual sands for use as fill when restoring natural landscapes. Careful testing of sediments before and after will establish the efficiency of the methods used, and ensure that end tailings contain as little as possible residual mercury. A series of settling ponds in which lime and flocculants are added will ensure maximum recovery of fine suspended sediments before recycling the wastewater back into the process in a closed circuit. A full economic balance of the activity will be analyzed, with the hopes that recovered gold can significantly offset the cost of restoration and reforestation. 

Better access to gold markets: More income for miners can also accrue from better access to markets for clean gold and tailings. Presently, miners sell their gold to middlemen that pay a low price for their gold. The project’s support to build the capacity of miners in record keeping of local ore production and gold yields (which are essential for operational quality control) are also key elements of OECD due diligence in proving the provenance of gold, so that miners can sell their gold directly to international refiners. 

The project will help broker uptake arrangements with international refiners, with local banks as intermediate gold custodians and fund transfer/holding agents, so that miners can safely accumulate enough gold for export to international refiners while still meeting their daily needs. As a result, miners will get a much higher value for their gold and more income stability, and this will incentivize others to formalize and become responsible miners. 

Where possible the project will assist interested and eligible groups in ethical gold certifications. The project might engage certification organizations to assess the top performing mining groups in the project for their possible certification, which will make recommendations for improvements and next steps.