Illegal mining in the Amazon is a growing threat to local communities, but it’s continuing to grow and expand, posing a threat not just to the environment but to people’s health as well. A few days ago, a rumour that gold was found in the Madeira river in the south of the Amazon rainforest sent would-be miners into a frenzy, with hundreds of rafts being spotted on the lake.
After a rather slow crackdown, the operations have now been stopped, but many fear miners are still active, but are now more careful about hiding.
The Madeira River is the biggest tributary of the Amazon river, the biggest in the world. Madeira alone contains40% of the fish species of all the Amazon basin, including several endemic species such as the Bolivian river dolphin. It’s 3,250 km (2,020 mi), during the rainy season its depth can reach 180 m (590 ft).
Fifteen days ago, around 300 hundred dredging rafts moved to the river due to the gold rumor. The activity is obviously illegal in such an important region of the Amazon basin — but that did little to stop miners.
The rafts appeared together in lines and placed themselves in plain sight as if nothing out of normal was happening. The rafts are equipped with pumps to suck the riverbed to find gold. Then, to make things worse, miners use toxic substances made of mercury to separate the gold from sand and other rocky material. The remains of the separation are then discarded in the river itself.
This situation is an environmental disaster waiting to happen, but the Brazilian government only started preparing on November 25, well after the presence of the rafts was clear. As the government made it a public statement it made most of the miners leave the area, until finally on November 27 the remaining rafts were burned down by the Federal Police.
Not so long ago, in 2018, scientists were ‘celebrating’ the decline of mining in the river. They published a paper discussing mercury pollution and attributed the concentration levels to be mostly from the ’80s when the activity was intense in the region.