Hydraulic fracturing (or "fracking" as it is popularly known) is an innovative technique that has allowed mining companies to reach rich, previously inaccessible oil and natural gas deposits. At a fracking site, water laced with sand and a cocktail of chemicals is injected deep underground, creating a web of fissures in subterranean rock formations. The cracks allow oil and gas to flow freely, making for easy extraction.
Some of the fracking fluid is removed from spent mines and disposed of offsite - but a large portion remains locked safely within the earth, at least according to mining companies. Despite industry assurances, the potential for chemical spills into groundwater supplies has caused widespread concern.


