Fracking involves the injection of water containing a surfactant and various other chemicals under high pressure into a source rock e.g. shale, causing the latter to fracture and release natural gas (principally methane).

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When the drilling is finished, water, combined with chemicals designed to reduce friction and serve other purposes, is injected from the surface into the well shaft at very high pressures, thereby fracturing the shale rock formations far below, and making it possible to extract economically the natural gas embedded in the shale.

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After about 20 minutes, the stagnant heat blended with fabric dust and other chemicals gets uncomfortable, yet not a single worker throughout the day is seen drinking water, and only a handful wear protective masks.

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