After word of a gold discovery on the Madeira River in the Brazilian Amazon in November, hundreds of gold miners flocked to the river. For over two weeks, over 400 barges floated the river about 70 miles from Manaus, the capital of the Amazonas state, before officials made moves to crack down on the illegal gold dredging (AP News). A Greenpeace spokesperson partially blamed President Jair Bolsonaro for the gold rush due to his pro-development stance (The Guardian).

Environmentalists were concerned by the operations, in part because miners were using mercury to separate gold from sediment. This process gives off toxic vapors and spills mercury in the water. Breathing in the vapors and touching the mercury poses dangers to the miners. Once mercury is in the river, it can spread as far as 300 miles downstream and gets into the food chain. Historically, miners have polluted Amazonian rivers, creating a path for logging and ranching to enter and bring about deforestation (Al Jazeera).

The gold rush continued unhindered for weeks as authorities discussed who was responsible for stopping the illegal activities. Brazil’s environmental protection agency, IBAMA, said the Amazonas state’s environmental agency, IPAAM, was responsible. The IPAAM said the National Mining Agency (ANM) was responsible because the anchored barges were under federal jurisdiction. IPAAM also noted that the federal police had to determine whether crimes were committed, and that the Navy was responsible for traffic and pollution of the river. The ANM said they only oversee legal mining, so this responsibility belonged to the police and courts (Reuters).

Eventually, Amazonas state prosecutors said authorities had 30 days to get the barges to leave. Federal police said they were determining the best way to proceed. In late November, police burned over 100 barges, and most of the other barges dispersed (Al Jazeera).