Lahtaw Kai draws an imaginary mountain into the air with her hands and uses her fingers to dot it with holes.

"At the top of the mountains, they drill holes and then pour chemicals like ammonium nitrate into the ground to extract the rare earth minerals at the bottom," the Myanmar environment activist told DW.

Lahtaw Kai — whose name we've changed for security reasons — was illustrating the so-called in-situ leaching technique, which has been applied for decades in mining rare earths in Myanmar's northern Kachin state.

The process begins at the top of the mountains, where chemicals are injected into the earth through a network of pipes. As the solution tracks downslope, it gathers rare earth elements, which are then collected in large ponds.

At hundreds of mining sites in the region, in-situ leaching is proving to be a huge risk to both the environment and local villagers.

"The rare earth sludge dries out in wood-fired kilns, and areas close to the mining sites constantly smell bad," said Lahtaw Kai, adding that she and her research team cannot stay there for more than 30 minutes because it's hard to breathe.

"But people are working there without gloves and masks. Companies don't provide protection. So, the workers get sick and then [the company] fires them and brings in new workers," she added.

Seng Li, a human rights activist currently based in Chiang Mai, Thailand, has researched mining sites in Myanmar's north and says the mountains used to be green before mining started.

"Now those mountains are very ugly, the river turned........

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