Du XVe in the XVIIe century, the conquistadors sought the legendary cities of gold. Now, from Peru to Brazil, via Colombia, Surinam or even French Guyana, the “garimpeiros”, the illegal miners, also dream of finding Eldorado. They explore the waterways in search of the smallest nugget, deforesting hectares of primary forests, decimating ecosystems by pouring liters of mercury into them that poison the soils and rivers.
A photo, released on February 7 by the United States Space Agency (NASA), taken by an astronaut from the International Space Station on December 24 at an altitude of 420 kilometers above the region of Madre de Dios and the rio Inambari, in the south-east of Peru, highlights the ravages of illegal gold panning, by revealing these “rivers of gold” which disfigure the Amazon.
This shot, taken using a 400 mm telephoto lens, reveals a landscape of craters filled with golden water, which are as many basins dug by “garimpeiros”, these miners who defy the authorities by prospecting for them. rivers to collect a few grams of gold.
Their prospecting sites, usually hidden from the eyes of satellites by cloud cover or appearing ocher or gray, have been exceptionally revealed thanks to the reflections of the sun’s rays. Each of these basins is surrounded by areas where the forest has been bulldozed. These deforested areas follow the course of ancient rivers where sediments, including gold, have been deposited.
Peru is the sixth largest producer in the world, with around 140 tonnes per year, part of which comes from these illegal mines. Most of it comes from the Madre de Dios region, located in the south-east of the country, on the border with Bolivia and Brazil. Over the past thirty-five years, the number of illegal sites created by these miners in search of small deposits of alluvial gold in the Peruvian Amazon has increased by 670%, reports a group of Peruvian and American researchers.
Deforestation and mercury pollution
The satellite image also shows the small town of Nueva Arequipa, located on the route of the South Interoceanic Highway, which crosses South America from Brazil to Peru, connecting the Atlantic to the Pacific. Inaugurated in 2011, this highway was initially intended to take off trade and tourism between the two countries. In practice, it only contributes to the acceleration of deforestation, by allowing artisanal miners to move from one site to another, so many lawless areas that feed all kinds of trafficking.
Tens of thousands of people are trying to make a living from this illegal activity which, in addition to being responsible for deforestation, pollutes the region, due to the use of mercury. The “garimpeiros” use this metal, which is liquid at room temperature, to amalgamate the gold flakes that they tear from the sands of rivers.
The mixture obtained is then heated to more than 400 ° C. in order to recover the precious metal. The World Wide Fund for Nature (WWF) reports that gold miners operating in Guyana use an average of 1.3 kg of mercury to recover 1 kg of gold. Until 2017, nearly 180 tonnes of mercury were used each year in the illegal exploitation of gold. This mercury, once evaporated, will pollute the environment:
“When it integrates aquatic environments, bacteria transform [le mercure] in methylmercury, a compound easily assimilated by living beings and a powerful neurotoxicant. Mercury contamination, both of natural origin and linked to illegal gold mining practices, can thus concentrate along aquatic food chains, reaching particularly high concentrations in the flesh of carnivorous fish. This results in contamination of the local populations for whom it is daily food. “
The authorities’ reaction
In 2017, Peru signed the Minamata Convention on Mercury. Launched by the United Nations Environment Program (UNEP) and signed by 128 States, this text seeks to “Protect human health and the environment against anthropogenic emissions and releases of mercury and mercury compounds”, as its preamble explains.
To comply with this commitment, Peru launched the “Mercury” operation at the start of 2019 in partnership with Usaid, the United States agency for international development. It targets illegal prospecting and first focused on the region of La Pampa, the epicenter of this activity which adjoins the Tambopata National Reserve, whose ecosystem is threatened.
In 2020, the authorities extended their operations to other illegal gold washing areas in the region and announced that the activity had decreased by 78%, but continued to threaten fragile areas, as the snapshot taken shows. by NASA.
