• The hole is then hydraulically fractured, or frac’d, by pumping a mixture of water, sand and additives (99.85% water) in to the well bore and casing under extremely high pressure. The mixture is forced out of the perforations and into the surrounding rock; the pressure causes the shale to fracture. This process widens the fractures in the rock and makes these pathways wider for the gas to flow more easily from the rock to the well. The process of perforation and fracturing can be repeated several times to cover the distance of the well.