The project was developed in the Rio Rayo estate, 7 kilometres south of Tarazá, in Antioquia. The site was selected as it enabled us to integrate our projects with the farm owner´s development projects, which include ideals that we share, such as environmental and social responsibility.
This farm is developing a sustainable and employment-generating integrated forestry and bee-keeping industry.
Acacia Mangium trees are planted on areas that were degraded by past traditional mining practices. These trees are rapid growing and yield quality timber. During their life cycle the trees also provide a continuous source of nectar for bees. The timber that is harvested is used to build the beehives.
The work model for EXUMAX in the “La Eternidad” pilot project was groundbreaking in Colombia as it was an alluvial gold mining operation that was 100% mercury-free. For primary concentration, the NZ Mobile Screens were used, followed by further processing within the Gold Lab, where the Mini Trommel and Gold Wheel performed the final stages.
The work team assembled for this project were people from the adjoining communities. In almost all cases it was their first chance at formal employment. Despite their lack of experience or education, and with the assistance of the EXUMAX training staff, they were able to learn all facets of the operation of a modern alluvial mine.
Before our intervention in the area of the La Eternidad project, it consisted of lands mostly degraded by old mining, with some small pockets that had retained a topsoil layer. This topsoil layer was carefully collected and stored in berms at the edges of the mine. An underlying sterile layer (consisting of clays with no gold content) was then moved to one side. The exposed gravels were then mined and left in situ, later covered by the reserved clays. The topsoil was then returned using a low ground pressure bulldozer.
The management of these soil layers and the subsequent recuperation were documented with a photographic record.
Post-mine use – Food Forest
In the design of the project, the later use of the area was considered. The area of La Eternidad was too small to establish a commercial agricultural enterprise, but due to our management the vitality of the soil was preserved. So a decision was made to convert the area into a “food forest” of mixed species, for the local community. A combination of plant types were used, to provide short, medium, and long term benefits. These included cassava, coconut, limes, bananas, and beans.