The Environmental Protection Agency of America where hydraulic fracturing is widespread, recently confirmed that chemicals linked to fracking had been found in the local drinking water reserves where the procedure was taking place. Major causes of concern are the safety of drinking water and the irrigation of agricultural land which could lead to contaminated crops. It is estimated that up to 40% of the waste water laden with the chemicals mentioned above, inevitably returns to the surrounding area's ground water suppl y. The fracking procedure uses literally millions of gallons of water to fracture the shale deposits. What is Fracking doing to the Water Supply? Uranium, mercury and lead are also known to be present. Hydrochloric acid is used to clean the drilling equipment while methanol and ammonium bisulfate prevent it corroding. Stabilisers such as potassium chloride and sodium carbonate control the acidity of the liquid. Peroxodisulfate regulate the viscosity of the liquid and bactericides are added to prevent the gas becoming contaminated. Some are proppants such as sintered bauxite and zirconium oxide which help to keep the fissures open. What are the Main Chemicals used in Fracking?Ĭhemicals are added to the liquid at a rate of between 0.5 and 2.0% to perform various functions. Other escaping gases include carbon monoxide, benzene, formaldehyde and nitrogen oxides. Consequently, environmentalists are alarmed at the detrimental effect fracking has on global warming. Methane is considered to be up to twenty-five times more harmful to the ozone layer than carbon emissions due to its effectiveness at confining heat. The greater part of it is collected but an estimated four percent escapes into the atmosphere. However, the shale gas that works its way to the surface consists primarily of methane. The explosive characteristics of fracking effectively release gas that is embedded between the layers of shale. What is Fracking doing to the Environment? Sand, ceramic beads and chemicals known as proppants are then channelled along the shafts to help keep the fissures open as the gas or oil is forced to the surface. The ever-increasing volume of fracking liquid forces its way into the minute fissures in the shale until the rock shatters. The next stage involves vast quantities of liquid being forced under extreme pressure to enter the shafts. These generally extend to approximately eight hundred metres but they can sometimes be several kilometres in length. When the well has reached the shale layer, drill rods are used to create multiple horizontal shafts. Fracking or hydraulic fracturing exploits shale's natural composition to encourage gas trapped between its layers to escape. Shale has a structure consisting of horizontal layers with minute channels between that are prone to fissility or splitting in a similar manner to slate. The bore hole passes through the upper layers of the earth's crust, the water table and various subterranean layers until it reaches the shale.Īs the most commonly found sedimentary rock, charcoal-coloured shale consists primarily of mud compressed together with various particles of calcite and quartz. Once geologists have identified an area that contains deposits such as shale gas, a bore hole is drilled vertically into the earth to a depth of around one mile. However, fracking has quickly become a controversial procedure due to concerns about its toxic impact on the environment and health. It is often employed in the oil industry for exploratory missions but its primary use is the extraction of identifiable deposits of natural shale gas or oil.