The fracking process extracts natural gas from deep below the Earth’s surface. The gas is trapped under layers of rock in a substance called Marcellus shale.In order to release it, energy companies build a well and then use special drilling equipment to make holes in the rock below.These bore holes may be around 1.5 miles deep.When the drills reach the Marcellus shale, conductors send electrical currents into it. The electricity causes the shale to fracture, making tiny cracks, or fissures.Next, machines inject a mixture of water, sand and chemicals called fracturing fluid into the bore hole. The fracturing fluid makes the cracks, or fissures, in the shale expand. When they remove the fracturing fluid, a little sand stays behind and keeps the fissures open. This helps to release the natural gas so that it can flow to the well on the surface. Containers on the surface collect the gas and then lorries transport it to market.