To Dump (in the Lake) or Not to Dump

That is the question facing the U.S. Supreme Court in a case on the waste from mining. David Biello reports

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[Below is the original script. But a few changes may have been made during the recording of this audio podcast.]

Our love of gold has driven mining across the world and, in the case of Alaska, prompted multiple gold rushes. Most recently, the Kensington mine north of Juneau amped up production and received a permit to dump its waste in nearby Slate Lake.

Such waste, called tailings, is rich in mercury, cadmium and other heavy metals, however, which are toxic to humans. The wastewater that goes with them also poisons the lake turning it acidic.


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Dumping it all in a lake is cheaper than building an artificial pond to store the detritus. Plus, mining companies argue, lakes help naturally contain the toxics that would otherwise leach out of the waste rock.

Kensington’s lawyer admitted, however, that the dumped waste would kill all aquatic life. But that, when the mining company was done, it would restock the lake. That fish kill is why environmentalists brought a lawsuit against the company that has now ended up in front of the U.S. Supreme Court.

The decision turns on a legal battle over semantics: can the to-be dumped rock be classified as waste or fill. But it will determine whether U.S. lakes can be turned into dumps or must be protected. And all for a pot of gold…

—David Biello

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