A Vast, Untapped Source of Lithium Has Just Been Found in The US
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Now public researchers on the other side of the country have uncovered another untapped reservoir – one that could cover nearly half the nation's lithium demands.

It's hiding in wastewater from Pennsylvania's gas fracking industry.

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Pennsylvania sits on a vein of sedimentary rock known as the Marcellus Shale, which is rich in natural gas. The geological foundation was deposited almost 400 million years ago by volcanic activity, and it contains lithium from volcanic ash.

Over vast stretches of time, deep groundwater has dissolved the lithium in these rocks, essentially "mining the subsurface", according to Justin Mackey, a researcher at the National Energy Technology Laboratory in Pennsylvania.

Mackey and his colleagues have now found that when wastewater is dredged up from the deep by fracking activities, it contains an astonishing amount of lithium.

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Their results suggest that the Marcellus Shale "has the capacity to provide significant lithium yields for the foreseeable future" – as long as fracking continues, that is.

If scientists can extract even a conservative amount of lithium from fracking wastewater in the state, they calculate it could meet more than 30 percent of the current US demand.

That sounds really promising, but the potential environmental impact of extracting lithium from fracking wastewater is as yet unexplored, and the wastewater only exists if fracking activity continues.