All that glitters is not gold. Sometimes, it's a river of mining waste.
A satellite photo taken after a devastating mining disaster in South Africa revealed a golden river of dried mud glimmering on the landscape. But its gleaming shine was caused by a torrent of potentially toxic sludge.
On Sept. 11, a dam at a diamond mine in Jagersfontein, South Africa collapsed, releasing a deluge of mining waste, known as tailings, which swept through the outskirts of the town and into the surrounding countryside. The disaster killed three people and injured around 40 others, according to Bloomberg. The flooding also destroyed dozens of houses, damaged cell phone towers, shut down roads, temporarily polluted drinking water and washed away hundreds of sheep, Reuters reported.
Tailings are a muddy mix of dust, crushed rock, water and other byproducts left over from mining. The surplus slurry often contains trace quantities of metals such as copper, mercury, cadmium and zinc, as well as other compounds including petroleum, sulfuric acid and even cyanide, according to Earthworks, a U.S.-based organization that supports communities impacted by mining and fossil fuel extraction.
A satellite image taken Oct. 4 by the Landsat 9 satellite, which is co-owned by NASA and the U.S. Geological Survey, shows a golden river of mud that was left behind as the spilled tailings flowed away from the mining town and eventually dried out. The striking image was released online Oct. 20 by NASA's Earth Observatory. Another photo of the area, taken by the Landsat 8 satellite the day before the dam collapsed, was also released for comparison.
In the new image, the break in the southern dam wall is clearly visible. From there the tailings flowed down the hillside in a massive, mile-wide (1.6 kilometers) wave that eventually funneled into the nearby Walwas Dam before spilling over into the adjoining Prosesspruit river, according to Earth Observatory.
In total, the dried tailings covered around 10 square miles (26 square km) of farmland, according to Earth observatory. Parts of the Prosesspruit also appear to have widened, suggesting that the torrent of mining waste may have eroded away the river's banks.
This golden river won't be around for long. The dried tailings will eventually begin to crumble and will either be blown away by the wind or washed away by the rain, according to Earth Observatory.
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Harry is a U.K.-based staff writer at Live Science. He studied Marine Biology at the University of Exeter (Penryn campus) and after graduating started his own blog site "Marine Madness," which he continues to run with other ocean enthusiasts. He is also interested in evolution, climate change, robots, space exploration, environmental conservation and anything that's been fossilized. When not at work he can be found watching sci-fi films, playing old Pokemon games or running (probably slower than he'd like).