In the US, gas-extraction in the Marcellus Shale has been linked to pollution and social conflict. Now Halliburton, Chevron and Exxon, among others, want to bring the so-called 'fracking' process to ...

While hydraulic fracturing (fracking) has made shale gas accessible and economical, large quantities of wastewater are produced over the lifespan of a well: drilling and fracturing a Marcellus shale ...