Gold Mining Reduced This Amazon Rainforest to a Moonscape. Now Miners Are Restoring It.

The Amazon rainforest, once a densely populated moonscape, has been carefully recreated by humans in an area that was heavily contaminated three years ago. This land was stripped of its dense vegetation by miners scouring the subsoil for tiny specks of gold, using mercury to separate the gold from the sediment. Many thought that a healthy forest would never thrive in impoverished, mercury-laden topsoil, and that the piles of sandy tailings, residue from the gold mining effort, and pools of wastewater were irremediable.

The liquid metal has seeped into the ecosystem, including the rivers, triggering an epidemic of chronic mercury poisoning among locals. The opportunity to let the forest grow back came via U.S. nonprofit Pure Earth, which works with communities across the Global South to remediate environmental problems left behind by mining, much of it illegal. Their biggest targets are mercury and lead contamination.

Madre de Dios is an obvious place for the group to operate, as the environmental devastation caused by gold miners in this pocket of the Peruvian Amazon has for years been the subject of international headlines. The financial meltdown of 2008 and the ensuing global recession triggered a chaotic, illegal goldrush here as thousands of impoverished Peruvians, mainly from the Andes, rushed to the jungle to comb through the soil and riverbeds for gold-rich sediment washed down from the mountains to the west. Nearly 250,000 acres of the Peruvian Amazon have been destroyed, according to a 2018 study by Wake Forest University researchers.

Today, around 50,000 people are thought to still work as illegal gold miners in Madre de Dios, making up a significant chunk of the local economy. There is also a smaller number of “informal miners” who have some but not all the necessary permits. Most local politicians, including Madre de Dios’ members of Peru’s national congress, broadly support the miners, who are a powerful constituency in the relatively sparsely populated jungle region.

Pure Earth, a nonprofit group, is working to restore the Peruvian Amazon rainforest by planting saplings in areas devastated by illegal gold mining. The group initially worked with legal miners, most of whom were here before the 2009 gold rush began. The nonprofit group is using this patch of land as a pilot project to show how the rainforest can be regenerated after the last traces of gold have been plucked from the soil.

The pilot project has taken a sustained outreach effort, as many miners are wary of or hostile to foreign NGOs, which have repeatedly called for gold mining to be banned or severely curbed in the Peruvian Amazon. France Cabanillas, Pure Earth’s local coordinator, has been appealing to the frustration of many miners at the heavy toll they have taken on the jungle and their desire to minimize their environmental footprint for the next generation.

Before the miners plant the carefully-selected mix of tree species, they had to prepare the earth by adding biochar (burnt organic material) and even molasses, which contain fixed carbon and minerals, along with various other nutrients. The miners also had to dig tiny moats around the saplings to prevent all of this new planting from being washed away. Now, after three years, the forest is visibly coming back.

The rejuvenated rainforest also mitigates the impact of the mercury used by many of the illegal miners. Research done by Pure Earth shows that the barren, sandy soil emits mercury, but in a rainforest, the ecosystem actually absorbs some of the metal, boosting public health. A 2021 meta-analysis by researchers at Nanjing University in China found that biochar can help keep mercury from migrating into the water table or the air. Other research finds promising effects from certain plants and fungi.

In addition to its work to regenerate the jungle, Pure Earth has shown other miners from AMATAF, the small legal mining association of which Ynfantes is a member, how to extract gold without using mercury. The techniques are more expensive and elaborate, such as using a “shaking table” to physically separate grains of the precious metal from the sediment and smelting with borax.

Read More @ NPR

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