On January 17, a gas well operating on state forest lands in Ward Township, a small settlement in America’s north-eastern state of Pennsylvania, experienced a blowout. The rupture sent an uncontrolled plume of drilling fluids and sand surging into the air, prompting the site’s operator, Canada-based Talisman Energy, to shut down all of its North American wells employing the same technology.
The Ward Township well was using a drilling method called hydraulic fracturing – more commonly known as “fracking” – which, largely thanks to its starring role in Oscar-nominated film Gasland, has shot onto the US public agenda. Now, concerns over its impact on water quality have prompted state and national environmental regulators to sit up and take notice. But can they move quickly enough?
Fracking involves drilling to depths of up to 2,300 metres, and then injecting a slurry comprising water, sand and a cocktail of chemicals into existing fissures in shale deposits at intense pressure. The sand props open the fractures and, when the slurry is pumped back to the surface, natural gas – freed from pores in the fractured rock – flows.
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