Hydraulic fracturing is commonly known as “Fracking”. This is the process whereby pressured rock (shale rock) is fractured by a pressurized liquid. Shale gas is natural gas trapped in shale rock. The technique involves mixing water with sand and chemicals, then injecting this mixture at a high pressure into a hole in the ground. This hole or wellbore is used for the extraction of gas and petroleum. The high pressure from the “fracking” creates very small cracks along the wellbore allowing trapped gas, petroleum and brine water to migrate to the well. When hydraulic pressure is removed from the well, these cracks are kept open by small grains of sand or aluminium oxide. Fracking is a very common technique for onshore well extraction of shale gas, oil and coal bed methane extraction. The Fracking procedure makes fluids flow more easily and greatly enhances productivity. Hydraulic fracturing was first used in 1947. As of 2012, 2.5 million fracking techniques have been performed on oil and gas wells worldwide, a million of them in the US. Hydraulic fracturing is economically viable due to technological developments, and, it is now easier to extract gas from previous unaccessible sites. Nearly all natural gas extraction today is by hydraulic fracturing.
Of late, the shale gas industry has come under intense scrutiny. Just this month, a row has erupted in the UK in the small village of Balcombe (West Sussex) over plans to start fracking there. Hundreds of protesters blocked the oil exploration site. Protesters fear that the fracking may trigger small earthquakes and pollute the water. Similarily in the US, opponents of fracking are putting pressure on the White House to curtain fracking. Britain is looking for new resources to meet its gas needs; imports from outside the North Sea is set to surpass domestic production by 2015. Despite there being potentially vast quantities of shale gas in the north of England, last year, 50 billion cubic metres of gas was imported. The Prime Minister has supported the fracking technique, saying that it will create more jobs and make Britain more energy efficient.
The massive expansion of US shale gas has driven down energy prices and cut dependency on imports. Some of the largest natural gas reserves are in America. 30% of the US gas is obtained today by fracking, compared to a decade ago when it was only 1%. In the EU, France and the Netherlands have banned the practice. Denmark and Poland are keen on the idea. Fracking has been used in the UK since the 1980s but was unofficially suspended in the UK between June 2011 and April 2012 after triggering small earthquakes. The ban has since been lifted and the UK will regulate fracking by focusing on laws and regulations rather than outright prohibition. Fracking did not attract attention until its use was proposed for onshore shale gas wells in 2007. And recently the protests in Balcombe, in 2013.
Environmental concerns over fracking have been raised since the 1980s and have been debated ever since. There have been conflicting conclusions from research studies. Although there is definitely proven conclusions from research, in some areas there hasn’t been very strong documented results. Differing studies have shown that carbon dioxide released due to fracking could accelerate climate change; other studies show it may well decrease it. It has been said that natural gas could replace coal and oil, cutting down on CO2 emmissions. Methane can also be released into the atmosphere from the fracking procedure. Methane is much more harmful and potent to the environment than CO2. Another gas that is flared from wells, is, hydrogen sulphide, which is an irritant and can cause problems to the central nervous system. Fracking operations in the US have been suspected of making the surrounding drinking water polluted – in areas such as Arkansas, Colorado, Pennsylvania, among others. Because hydraulic fracturing uses a huge volume of water for the pressure, i.e between 1.2 and 3.5 million US gallons, it can take precious reserves from residential and arid areas. Although the chemicals used in the fracking process are generally harmless, they can be carcinogenic in high concentrations. It has been reported that there has been dangerous air pollution, destroyed streams, devasted landscapes and induction of earthquakes due to fracking. A study from the US has said that workers risked developing lung disease due to the silica used in the fracking procedure. There is some concern over the levels of radiation in wastewater from sites and its potential impact on public health. As of 2012, because of these findings and others, it has been reported that the U.S. Environmental Protection Agency is conducting comprehensive field research.
In the UK,the HSE monitors site safety and well safety of hydraulic fracturing. The two main regulations are the The Borehole Site and Operations Regulations 1995 (BSOR) and the The Offshore Installations and Wells (Design and Construction, etc) Regulations 1996 (DCR). The former applies to shale gas operations and is generally concerned with site health and safety. The former applies to both onshore and offshore extraction from gas wells. The HSE and the Environment agency (EA) work together to ensure that there is environmental protection and planning authorisation considerations in fracking operations. Shale gas wells must be designed, built and operated in line with these standards and operations. The Environment Agency is responsible for managing water resources, groundwater discharge activities, issuing permits for radioactive substances and for certain industrial, farming and waste management activities involving fracking.
It has been reported that areas to regule in the fracking technique should include checking the concrete casing inside the well bores. It should be strong enough to prevent groundwater contamination. This should be a legal requirement. The toxic fluid released as a by- product of fracking, should, be stored in tanks so it dosnt leak out and contaminate the surrounding air and soil. To prevent seepage of fluid, fracking should be carried out in as much isolation as possible, far away from freshwater aquifers. Also, gas companies should inject tracers so that fluid can be monitored if it ends up in residents tapwater. Aquifers and drinking-water wells should be tested before drilling and routinely to control any contamination of the ground water.
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