Overview

Natural gas is becoming known in the United States as the future of greener energy. Natural gas is cleaner burning than other current energy sources, e.g. coal, meaning it produces less greenhouse gasses when it is converted into usable energy. In 2010 the Energy Information Administration estimated that the United States possesses 2,552 trillion cubic feet of potential natural gas reservoirs. These reservoirs could potentially supply the United States with energy for the next 110 years, and could lower its dependency on foreign energy sources.¹

827 trillion cubic feet of the natural gas in the United States is stored in shale formations deep within the earth. Much of the natural gas in the shale formations is trapped in small pockets, and to access this gas the gas companies must stimulate the shale through a process called hydraulic fracturing.¹ Hydraulic fracturing, also known as "hydrofracking" or fracking, creates or enlarges fractures in the shale so that the gas can be released into the well and brought to the surface. Though hydrofracking was initially a relatively simple procedure involving a vertical well and a simple fluid under high pressure, now the process of fracturing the shale formations, which are sometimes incredibly deep, involves vertical and horizontal drilling techniques and complex fluids containing many gallons of water or diesel, sand, and numerous chemical additives.²

Hydraulic fracturing is now used at almost every natural gas well in the United States so that the energy companies can release as much gas as possible from each well. Recently, however, hydrofracking has become a widespread environmental issue being studied by the House of Congress, the Environmental Protection Agency (EPA), and state governments across the country. There are a number of environmental issues concerning hydraulic fracturing. One concern is that millions of gallons of chemically laced fluid, known as "fracking fluid," are pumped into each gas well thousands of miles into the earth; the majority of the fluid remains in the well because it cannot be recovered. Another concern is that some of the chemicals added to the fracking fluid are considered proprietary by the companies that produce the chemicals, so the energy companies often do not know exactly what they are pumping into the ground. There are also many concerns about how the chemicals in the fluid and the natural gas being released are affecting the quality and quantity of underground drinking water sources located near fracking sites. There are numerous personal reports from all over the United States claiming that drilling and fracking for natural gas has contaminated or depleted underground drinking water sources to a point that they are no longer usable.

The recent advances in drilling technology and fracking fluid development, along with the rising environmental concern, have made hydraulic fracturing a hot news topic. The House of Congress, along with the EPA, is doing research to determine if hydrofracking is causing the many environmental impacts that it has been claimed to cause. Their research, along with the research and reports made by scientists and citizens across the United States, may allow us to find the truth behind the environmental and possibly toxicological effects of hydraulic fracturing.

Map of shale formations in the United States 3

History

Originally used, and often illegally, to break up oil-bearing formations, fracturing can be traced back to the 1860s. Liquid or solidified nitroglycerin was blasted into rock wells in Pennsylvania, New York, Kentucky, and West Virginia to stimulate initial flow and overall recovery of oil. This same method was soon used in gas and water wells as well. It wasn't until the 1930s that nonexplosive fluids, i.e. acid, started to be used, combined with high pressures to create fractures that would be etched open with the acid.²

In the 1940s Floyd Farris of Stanolind Oil and Gas Corporation performed a study to enhance this technology further. The first "Hydrafrac" was performed in 1947 in Grant County, Kansas, and it used 1000 gallons of napthenic acid and palm oil (napalm) combined with gasoline and a gel breaker to stimulate flow of gas in a limestone formation. This initial fracking process was not very beneficial.²

In 1949 Haliburton Oil Well Cementing Company was issued a patent with an exclusive license to the hydraulic fracturing process. In the first year 332 oil wells were treated with crude oil or a combination of crude oil, gasoline, and sand. The wells on average increased 75% in production. In the mid-1950s more than 3000 wells were bring fractured per month.²

In 1968 Haliburton's patent expired and other companies began fracturing oil and gas wells around the country. The initial fracturing treatments only contained about 750 gallons of fluid and 450 lbs of sand, which is small compared to treatments used today which can contain 60,000-1 million gallons of fluid and 100,000 to 5 million lbs of proppant. ²

Hydraulic fracturing how now become a common practice for oil and gas companies. The components used in fracturing processes have now developed, and continue to develop, into complicated formulas made up of water, sand, diesel, chemicals, gels, and proppants. With drilling developments and the recent advances in horizontal drilling, the methods used in the hydraulic fracturing process have also changed drastically into a highly computerized procedure. The rise in use and development is because hydraulic fracturing has been an incredibly lucrative process, and has been estimated to have increased the United States' recoverable reserves of oil by 30% and of natural gas by 90%.²

Fracturing Fluid Composition

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References

[1] http://democrats.energycommerce.house.gov/sites/default/files/documents/Hydraulic%20Fracturing%20Report%204.18.11.pdf
[2] Hydraulic Fracturing: History of An Enduring Technology by Carl T. Montgomery and Michael B. Smith, NSI Technologies. and Hydraulic Fracturing: The Fuss, The Facts, The Future. by Robin Beckwith, JPT/JPT Online. JPT December 2010. http://www.spe.org/jpt/print/archives/2010/12/10Hydraulic.pdf
[3] http://www.netl.doe.gov/technologies/oil-gas/publications/EPreports/Shale_Gas_Primer_2009.pdf
[4] http://www.epa.gov/ogwdw/uic/pdfs/cbmstudy_attach_uic_ch04_hyd_frac_fluids.pdf