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The environmental impact of hydraulic fracturing affects land use and water consumption, methane emissions,〔http://www.mintpressnews.com/2500-square-mile-methane-plume-silently-hovering-western-us/200313/〕 air emissions, water contamination, noise pollution, and health. Water and air pollution are the biggest risks to human health from hydraulic fracturing. Research is underway to determine if human health has been affected, and rigorous adherence to regulation and safety procedures is required to avoid harm.〔 Noise from hydraulic fracturing and associated transport can also affect residents and local wildlife. Hydraulic fracturing fluids include proppants and other substances, which may include toxic chemicals.〔 In the United States, such additives may be treated as trade secrets by companies who use them. Lack of knowledge about specific chemicals has complicated efforts to develop risk management policies and to study health effects.〔〔 In other jurisdictions, such as the United Kingdom, these chemicals must be made public and their applications are required to be nonhazardous.〔 Water usage by hydraulic fracturing can be a problem in areas that experience water shortage. Surface water may be contaminated through spillage and improperly built and maintained waste pits, in jurisdictions where these are permitted.〔 Further, ground water can be contaminated if fluid is able to escape during fracking. Produced water, the water that returns to the surface after fracking, is managed by underground injection, municipal and commercial wastewater treatment, and reuse in future wells.〔 There is potential for methane to leak into ground water and the air, though escape of a methane is a bigger problem in older wells than in those built under more recent legislation.〔 Hydraulic fracturing causes induced seismicity called microseismic events or microearthquakes. The magnitude of these events is too small to be detected at the surface, being of magnitude M-3 to M-1 usually. However, fluid disposal wells (which are often used in the USA to dispose of polluted waste from several industries) have been responsible for earthquakes up to 5.6M in Oklahoma and other states.〔 Governments worldwide are developing regulatory frameworks to assess and manage environmental and associated health risks, working under pressure from industry on the one hand, and from anti-fracking groups on the other.〔〔 In some countries like France a precautionary approach has been favored and hydraulic fracturing has been banned.〔〔 Some countries such as the United States have adopted the approach of identifying risks before regulating. The United Kingdom's regulatory framework is based on conclusion that the risks associated with hydraulic fracturing are manageable if carried out under effective regulation and if operational best practices are implemented.〔 == Air emissions == A report for the European Union on the potential risks was produced in 2012. Potential risks are "methane emissions from the wells, diesel fumes and other hazardous pollutants, ozone precursors or odours from hydraulic fracturing equipment, such as compressors, pumps, and valves". Also gases and hydraulic fracturing fluids dissolved in flowback water pose air emissions risks.〔 "In the UK, all oil and gas operators must minimise the release of gases as a condition of their licence from the Department of Energy and Climate Change (DECC). Natural gas may only be vented for safety reasons." 〔(UK Department of Energy and Climate Change. February 2014 "Fracking UK shale: local air quality" )〕 Also transportation of necessary water volume for hydraulic fracturing, if done by trucks, can cause emissions.〔 Piped water supplies can reduce the number of truck movements necessary.〔(【引用サイトリンク】url=https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/277211/Water.pdf )〕 A report from the Pennsylvania Dept of Environmental Protection indicated that there is little potential for radiation exposure from oil and gas operations. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Environmental impact of hydraulic fracturing」の詳細全文を読む スポンサード リンク
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