Hydraulic fracturing in the United States
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Hydraulic fracturing in the United States has been used for over 60 years, and over a million wells have been hydraulic fractured over that time. Environmental safety and health concerns about hydraulic fracturing emerged in the 1980s, and are still being debated at the state and federal levels.
Non-hydraulic fracturing 
Fracturing as a method to stimulate shallow, hard rock oil wells dates back to the 1860s. It was applied by oil producers in Pennsylvania, New York, Kentucky, and West Virginia by using liquid and later also solidified nitroglycerin. Later, the same method was applied to water and natural gas wells. The idea to use acid as a nonexplosive fluid for well stimulation was introduced in the 1930s. Due to acid etching, fractures would not close completely and therefore productivity was enhanced. The same phenomenon was discovered with water injection and squeeze cementing operations.
Hydraulic fracturing in quarrying 
The first industrial use of hydraulic fracturing was as early as 1903, according to T.L. Watson. Before that date, hydraulic fracturing was used at Mt. Airy Quarry, near Mt Airy, North Carolina where it was (and still is) used to separate granite blocks from bedrock.
Hydraulic fracturing in oil and gas wells 
The relationship between well performance and treatment pressures was studied by Floyd Farris of Stanolind Oil and Gas Corporation. This study became a basis of the first hydraulic fracturing experiment, which was conducted in 1947 at the Hugoton gas field in Grant County of southwestern Kansas by Stanolind. For the well treatment 1,000 US gallons (3,800 l; 830 imp gal) of gelled gasoline and sand from the Arkansas River was injected into the gas-producing limestone formation at 2,400 feet (730 m). The experiment was not very successful as deliverability of the well did not change appreciably. The process was further described by J.B. Clark of Stanolind in his paper published in 1948. A patent on this process was issued in 1949 and an exclusive license was granted to the Halliburton Oil Well Cementing Company. On March 17, 1949, Halliburton performed the first two commercial hydraulic fracturing treatments in Stephens County, Oklahoma, and Archer County, Texas. Since then, hydraulic fracturing has been used to stimulate approximately a million oil and gas wells.[unreliable source]
Massive hydraulic fracturing 
Pan American Petroleum applied the first massive hydraulic fracturing (also known as high-volume hydraulic fracturing) treatment in the non-communist world to a well in Stephens County, Oklahoma in 1968. The treatment injected half a million pounds of proppant into the rock formation. The definition of massive hydraulic fracturing varies somewhat, but is generally used for treatments injecting greater than about 150 mt, or 300,000 pounds of proppant.
In the 1960s, American geologists became increasingly aware that there were huge volumes of gas-saturated rocks with permeability too low (generally less than 0.1 millidarcy) to recover the gas economically. The US government experimented with using underground nuclear explosions to fracture the rock and enable gas recovery from the rock. Such explosions were tried in the San Juan Basin of New Mexico (Project Gasbuggy, 1967), and the Piceance Basin of Western Colorado (Project Rulison, 1969, and Project Rio Blanco, 1973) but the results were disappointing, and the tests were halted. The petroleum industry turned to the new massive hydraulic fracturing technique as the way to recover tight gas.
In 1973, Amoco introduced massive hydraulic fracturing to the Wattenberg Gas Field of the Denver Basin of Colorado, to recover gas from the low-permeability J Sandstone. Before massive hydraulic fracturing, the Wattenberg field was uneconomic. Injected volumes of 132,000 or more gallons, and 200,000 or more pounds of sand proppant, succeeded in recovering much greater volumes of gas than had been previously possible. In 1974, Amoco performed the first million-pound frac job, injecting more than a million pounds of proppant into the J Sand of a well in Wattenberg Field.
The success of massive hydraulic fracturing in the Wattenberg Field of Colorado was followed in the late 1970s by its use in gas wells drilled to tight sandstones of the Mesaverde Group of the Piceance Basin of western Colorado.
Starting in the 1970s. thousands of tight-sandstone gas wells in the US were stimulated by massive hydraulic fracturing. Examples of areas made economic by the technology include the Clinton-Medina Sandstone play in Ohio, Pennsylvania, and New York; the San Juan Basin in New Mexico and Colorado; numerous fields in the Green River Basin of Wyoming; and the Cotton Valley Sandstone trend of Louisiana and Texas.
Hydraulic fracturing in coalbed methane wells 
Coalbed methane wells, which first began to be drilled in the 1980s, are commonly hydraulicly fractured to increase the flow rates to the well. Hydraulic fracturing is commonly used in some coalbed methane areas, such as the Black Warrior Basin and the Raton Basin, but not in others, such as the Powder River Basin, depending on the local geology. Injected volumes tend to be much smaller than those of either tight gas wells or shale gas wells; a 2004 EPA study found a median injected volume of 57,500 gallons for coalbed methane wells.
Massive hydraulic fracturing in horizontal wells 
Horizontal oil or gas wells were unusual until the 1980s. Then in the late 1980s, operators all along the Texas Gulf Coast began completing thousands of oil wells by drilling horizontally in the Austin Chalk, and giving massive slickwater hydraulic fracturing treatments to the wellbores. Horizontal wells proved much more effective than vertical wells in producing oil from the tight chalk.
Hydraulic fracturing in shales 
In the 1970s the United States government initiated the Eastern Gas Shales Project, a set of dozens of public-private hydro-fracturing pilot demonstration projects. During the same period, the Gas Research Institute, a gas industry research consortium, received approval for research and funding from the Federal Energy Regulatory Commission.
In 1997, based on earlier techniques used by Union Pacific Resources, now part of Anadarko Petroleum Corporation, Mitchell Energy, now part of Devon Energy, developed the hydraulic fracturing technique known as "slickwater fracturing" that made the shale gas extraction economical.
Between 2005 and 2010 the shale-gas industry in the United States grew by 45% a year. As a proportion of the country's overall gas production, shale gas increased from 4% in 2005 to 24% in 2012.
According to oilfield services company Halliburton, as of 2013 more than 1.1 million hydraulic fracturing jobs have been done in the United States (some wells are hydraulically fractured more than once), and almost 90% of new US onshore oil and gas wells are hydraulically fractured.
Typical process for drilling a well 
First step in the process is to identify prospective gas reserves in the ground and obtaining required permits for gas well construction. These permits are regulated by state agencies and requirements to qualify for the permit vary from state to state. Once the permit is obtained, a company proceeds with preparing the surface at the well site. This usually involves a 4-5 acre area that is cleared to setup stage bed, waste water site and temporary gas storage facility. Next step in the process is the drilling and casing of the well. In this process, a bore machine drills vertically in the ground while adding steel casings very few feet in a reverse telescope manner. The bore well process is very similar to bore well process for constructing water wells. The casing helps keep the well open by providing structural support as well as prevent fluid and gas flow into the surrounding ground. Once the casing is in class, cement is pumped down inside the casing and back up on the outside of the casing. This is done to cement the casing in the formation as well as to prevent any leakage or flow of the gas and fluids behind the casing. This is one of the most critical steps involved with designing an environmentally safe and efficient gas well.
Economic impact 
Oil and gas supply 
Gas production from tight sandstone reservoirs made up 26 percent of US gas production in 2010. Production from shales made up another 23 percent of US gas production, so that massive hydraulic fracturing made possible 49 percent of US gas production in 2010. Increased US production resulted in decreased natural gas imports: in 2012, the US imported 32% less natural gas than it had in in 2007. In 2013, the US Energy Information Administration projected that imports will continue to shrink due to increases in tight gas and shale gas, and the US will become a net exporter of natural gas some time around 2020.
Increased US oil production from hydraulically fractured tight oil wells was mostly responsible for the decrease in US oil imports since 2005 (decreased oil consumption was also an important component). The US imported 52% of its oil in 2011, down from 65% in 2005.
Proponents of hydraulic fracturing tout its potential to make the United States the world's largest oil producer and make it an energy leader. Proponents say that hydraulic fracturing would give the United States energy independence. In 2012, the International Energy Agency projected that the United States, now the world's third-largest oil producer behind Saudi Arabia and Russia, will see such an increase in oil from shales that the US will become the world's top oil producer by 2020.
Globally, gas use is expected to rise by more than 50% compared to 2010 levels, and account for over 25% of world energy demand in 2035. Anticipated demand and higher prices abroad have motivated non-US companies to buy shares and invest in US gas and oil companies, and in the case of the Norwegian company Statoil, to buy an American shale oil company outright leading to greater international control of US oil and gas resources.
Some geologists say that the well productivity estimates are inflated and minimize the impact of the reduced productivity of wells after the first year or two. A June 2011 New York Times investigation of industrial emails and internal documents found that the financial benefits of unconventional shale gas extraction may be less than previously thought, due to companies intentionally overstating the productivity of their wells and the size of their reserves. The same article said, "Many people within the industry remain confident." T. Boone Pickens said that he was not worried about shale companies and that be believed they would make good money if prices rise. Pickens also said that technological advances, such as the repeated hydrofracking of wells, was making production cheaper. Companies that specialize in shale gas have diversified into lucrative products such as propane and butane.
Gas price 
According to the World Bank, as of November 2012, the increased gas production due to horizontal drilling and hydraulic fracturing in the US had driven US gas prices down to less than one-third of natural gas prices in Europe, and to one-fifth of natural gas prices in Japan. Lower natural gas prices in the US have encouraged the replacement of coal- with gas-fired power plants, but have also discouraged the switch to renewable sources of energy. Facing a supply glut and consequent further price drops in 2012, some large US gas producers announced plans to cut natural gas production; however, production rates rose to all-time highs, and natural gas prices remained near ten-year lows.
Companies have sought and received permission from the US Department of Energy (DOE) to export gas to Europe and Asia (e.g., China and Korea), They have asked for permission to build a new pipeline through Pennsylvania and Maryland to transport liquid natural gas (LNG) to new export terminals in Maryland to facilitate the export of natural gas and oil. Possible terminal locations include Sparrow's Point, (Baltimore) and Lusby, Maryland.
Oil and natural gas companies have recently sought to build a new pipeline through Pennsylvania and Maryland to new liquid natural gas export terminals in Maryland, in order to increase profits by exporting gas to Europe and Asia. Critics have charged that such a move could threaten the national energy security provided by gas from hydraulically fractured shale gas wells.
Economic effects of hydraulic fracturing include an increase in jobs, and an increase in business. The EPA states that it is unclear on a local level how and for how long hydraulic fracturing affects a community economically. It is hypothesized that hydraulic fracturing may not provide jobs to local communities due to the specialized nature of hydraulic fracturing tasks. Also, communities’ local resources could potentially be taxed due to the increase in industry traffic or if an accident occurs.
Property owners 
Economic effects of hydraulic fracturing include payments to property owners. Concerns have also been raised regarding the terms and clarity of the leases energy companies are signing with landowners, as well as the manner in which they are sold and the tactics used by companies in implementing them.
Another question has been the effect the leases can have on mortgages, with some lenders becoming reluctant to loan money "for a piece of land that ends up storing the equivalent of an Olympic-size swimming pool filled with toxic wastewater from drilling" or making mortgages conditional on not signing a drilling contract.
Nationwide Insurance has issued a statement that its policies do not cover hydraulic fracturing related damage. The company said that it issued the memo because their research led them to decide that the financial exposure created by such coverage was too great. The company will not cover damages to land involved in hydraulic fracturing operations, damages resulting from hauling water, pipe, and lumber to and from drill sites, and damages resulting from the use of bulldozers, dump trucks and other vehicles used in conjunction with hydraulic fracturing. Company representatives said that they have historically not insured the oil and gas business, but added that they were uncomfortable with hydraulic fracturing's unique risks and could not provide coverage at a reasonable price. Jeffrey Hanneman, the director of environmental practice for Aon Risk Solutions, said the decision would be unlikely to signal a wider trend. Hanneman said that while some insurance companies have been reluctant to offer coverage to tracking and related activities, there have been no substantial claims except for rare claims against companies owning or operating wells. Mike Elmendorf, head of the Associated General Contractors of New York State said that AGCNY members did not welcome Nationwide's decision, and that it was hard to understand, anti-job creation, and had no factual basis. Simon Lomax, the research director for Energy In Depth, a petroleum industry group, has called the decision reckless and uninformed.
Geisinger Health System, a physician-led health care system, serves many patients who live in the Pennsylvania towns where Marcellus Shale gas drilling (hydraulic fracturing) is occurring. Geisinger has 2.6 million patients, many hospitals and clinics in the area, and an insurance program. It has archives that include historical health care data for the region. The company is concerned about future health costs that might be incurred due to the practice of hydraulic fracturing. In addition to drinking water quality concerns, in 2012 OSHA and NIOSH released a warning about worker exposure to crystalline silica, which is related to silicosis, and a 2012 OSH article outlined the risk of worker radiation exposure. Geisinger is currently conducting a study of the health impact of hydraulic fracturing using its database's capacity to examine links between drilling and health by dates and locations, as well as identify control populations.
Environmental and health impact 
There are environmental concerns, including contamination of ground water, risks to air quality, the potential migration of gases and hydraulic fracturing chemicals to the surface, the potential mishandling of waste, and the health effects of these, like cancer. There is already evidence of environmental contamination, and it has been predicted that exposure to chemicals in hydraulic fracturing fluid will increase as gas wells using this technology proliferate. Gas drilling companies are reluctant to reveal the proprietary substances in the fluid.
An example of the composition of a typical fracturing fluid can be found in Typical Solution Used in Hydraulic Fracturing, energyindepth.org. A more complete listing of chemicals used in fracturing fluid, which includes kerosene, benzene, tolulene, xylene, formaldehyde to name a few, may be found in Chapter 5 Natural Gas Development Activities And High‐Volume Hydraulic Fracturing.[clarification needed]</ref>
EPA hydraulic fracturing study 
In 2010 Congress requested that the EPA undertake a new, broader study of hydraulic fracturing. The report is slated for release in 2012. The purpose of the EPA study regarding Hydraulic Fracturing is to examine the effects of hydraulic fracturing on the water supply, specifically for human consumption. The research aims to examine the full scope of the water pathway as it moves through the hydraulic fracturing process, including water that is used for the construction of the wells, the fracturing mixture, and subsequent removal and disposal. Fundamental research questions include:
- How might large volume water withdrawals from ground and surface water impact drinking water resources?
- What are the possible impacts of releases of flowback and produced water on drinking water resources?
- What are the possible impacts of inadequate treatment of hydraulic fracturing wastewaters on drinking water resources?
The Scientific Advisory Board reviewed the study plan in early March 2011. In June 2011, the EPA announced the locations of its five retrospective case studies, which will examine existing hydrofracking sites for evidence of drinking water contamination. They are:
- Bakken Shale - Kildeer, and Dunn Counties, North Dakota
- Barnett Shale - Wise and Denton Counties, Texas
- Marcellus Shale - Bradford and Susquehanna Counties, Pennsylvania
- Marcellus Shale - Washington County, Pennsylvania
- Raton Basin - Las Animas County, Colorado
Dr. Robin Ikeda, Deputy Director of Noncommunicable Diseases, Injury and Environmental Health at the CDC noted that none of the following EPA investigation sites were included in the final version of EPA’s Study of the Potential Impacts of Hydraulic Fracturing on Drinking Water Resources: Dimock, Pennsylvania; LeRoy, Pennsylvania; Pavillion, Wyoming; Medina, Ohio; Garfield County, Colorado.
Research should be completed by the end of 2012, and the EPA's Hydraulic Fracturing Report is expected to be completed in 2014.
Industry forces applied pressure to exclude the study of tracer isotopes from the study. The study's Science Advisory Board advised the EPA to delete proposed toxicity tests from the study scope, due to limited time and funds. However, some members of the Science Advisory Board (SAB) urged the SAB to advise the EPA to reinstate the toxicity testing of frack chemicals. Chesapeake Energy agreed, stating “an in-depth study of toxicity, the development of new analytical methods and tracers are not practical given the budget and schedule limitation of the study.” Thus, despite concerns about the elevated levels of iodine-131 (a radioactive tracer used in hydraulic fracturing) in drinking water in Philadelphia and Pittsburgh, downstream from hydraulic fracturing sites, iodine-131 is not listed among the chemicals to be monitored in the draft plan for the study. Other known radioactive tracers used in hydraulic fracturing but not listed as chemicals to be studied include isotopes of gold, xenon, rubidium, iridium, scandium, and krypton.
The EPA Hydraulic Fracturing Draft Study Plan can be found here.
Groundwater quality studies 
Jackson County, West Virginia, 1987 
In 1987, an Environmental Protection Agency (EPA) report was published that indicated fracture fluid invasion into a well in West Virginia. The well, drilled by Kaiser Exploration and Mining Company, was found to have induced fractures that allowed fracture fluid to contaminate groundwater. The American Petroleum Institute agreed that hydraulic fracturing had caused the drinking water contamination, and the EPA held it up as an example of the hazards created by the technique.
EPA, 2004 
A 2004 EPA study on hydraulic fracturing in coalbed methane wells concluded that the process was safe in such cases, and didn't warrant further study, because there was "no unequivocal evidence" of health risks to groundwater, and the fluids were neither necessarily hazardous nor able to travel far underground. The EPA report did find uncertainties in knowledge of how fracturing fluid migrates through rocks, and recommended that diesel fuel not be used as a component of fracturing fluid in coalbed methane walls due to its potential as a source of benzene contamination; in response, well service companies agreed to stop using diesel fuel in coalbed methane wells. One of the authors of the 2004 EPA report noted that it studied only hydraulic fracturing in coalbed methane wells.
Dimock Township, Pennsylvania, 2009 
An investigation was initiated after a Pennsylvania water well exploded on New Year's Day in 2009. The state investigation revealed that Cabot Oil & Gas Company "had allowed combustible gas to escape into the region's groundwater supplies." Arsenic, barium, DEHP, glycol compounds, manganese, phenol, methane, and sodium were found in unacceptable levels in the wells. In April 2010, the state of Pennsylvania banned Cabot Oil & Gas Corp. from further drilling in the entire state until it plugs wells believed to be the source of contamination of the drinking water of 14 homes in Dimock Township, Pennsylvania. Cabot Oil & Gas was also required to financially compensate residents and provide alternative sources of water until mitigation systems were installed in affected wells.
Pavillion, Wyoming, 2012 
Complaints about water quality from residents near a gas field in Pavillion, Wyoming prompted an EPA groundwater investigation, which reported detections of methane and other chemicals, some used or produced in fracking, and some at dangerous levels. A draft report stated that the impact to ground water could be explained by fracking. The report said that ground water contamination of the nature found in Pavilion is "typically infeasible or too expensive to remediate or restore (GAO 1989)."
In 2012 the U.S. Geological Survey tested one of two EPA monitoring wells near Pavillion, Wyoming, and found evidence of methane, ethane, diesel compounds and phenol, which the EPA had also identified in its 2011 report. Rob Jackson, an environmental scientist at Duke University, described the methane, ethane, and propane concentrations as very high, consistent with fossil fuel rather than natural sources. In 2012, the EPA retested water in Pavillion, and briefed the homeowners, but has not yet released the results to the public. Pavillion resident John Fenton reported that the EPA told him the recent test results were consistent with previous results, and that the EPA recommended that they don't cook with or drink their water.
University of Texas, 2012 
A 2012 University of Texas at Austin Energy Institute study (which was later withdrawn) found that all steps in the process except the actual injection of the fluid (which proponents artificially separated from the rest of the process and designated "hydraulic fracturing") have resulted in environmental contamination. The radioactivity of the injected fluid itself was not assessed in the University of Texas study. The other stages or "phases of the shale gas development life cycle" are (1) drill pad construction and operation, (2) the construction, integrity, and performance of the wellbores, (3) the flowback of the fluid back towards the surface, (4) blowouts and spills, (5) integrity of other pipelines involved and (6) the disposal of the flowback, including waste water and other waste products. These stages were all reported to be possible sources of contamination in the University of Texas study. The study concluded that if hydraulic fracturing is to be conducted in an environmentally safe manner, these issues need to be addressed first. There are extensive links between UT and the oil and gas industry, with giving Royal Dutch Shell to the university currently standing at more than $24.8 million, $4m alone having been handed over for 2012. Since 2011, Shell has partnered Texas in a program called Shell-UT Unconventional Research, and the university has a similar research program in place with Exxon Mobil. Halliburton, the largest supplier of fracking services in the United States, has also given millions of dollars to the university. Statoil announced a $5m research agreement (part of which will focus on oil shale) with UT's Bureau of Economic Geology in September 2011, whose program director, Ian Duncan, was the senior contributor for the parts of the Texas study to do with the environmental impacts of shale gas development.
A 2011 study by Congressional Democrats found that, in the process of hydraulic fracturing, "oil and gas companies injected hundreds of millions of gallons of hazardous or carcinogenic chemicals into wells in more than 13 states from 2005 to 2009," according to the New York Times. The Congressional study had identified 750 different chemicals in that fluid; 29 of which are considered to be known or possible hazards or carcinogens. A 2011 investigation by the New York Times based on various leaked EPA documents found that hydraulic fracturing had resulted in significant increases of radioactive material including radium and carcinogens including benzene in major rivers and watersheds. At one site the amount of benzene discharged into the Allegheny River after treatment was 28 times accepted levels for drinking water.
A study published in May 2011 by researchers at Duke University found that "levels of flammable methane gas in drinking water wells increased to dangerous levels when those water supplies were close to natural gas wells." Water samples from 68 private water wells in the states of Pennsylvania and New York were tested and some were found to have extremely high concentrations of methane: 64 milligrams of methane per liter of drinking water, compared with a normal level of one milligram or lower. The study found that, on average, methane concentrations 17 times above normal in samples taken from water wells near shale gas drilling sites employing hydraulic fracturing. According to one of the authors of the study, "That sort of concentration is up at a level where people worry about an explosion hazard." The average concentration of methane in the water wells near drilling sites lies within a range that, according to the U.S. Department of the Interior, is dangerous and requires urgent "hazard mitigation" action. They found that the type of gas detected at high levels in the water was the same type of gas that energy companies were extracting from thousands of feet underground, strongly implying that the gas may be seeping underground through natural or man-made faults and fractures, or coming from cracks in the well structure itself ". The study concluded that fracking has seriously contaminated shallow groundwater supplies in northeast Pennsylvania with flammable methane. The study does not discuss how pervasive such contamination might be in other areas where drilling for shale gas has taken place. Though the study found thermogenic groundwater methane concentrations were higher near active drilling sites compared to neighboring nonextracting sites, no traces of hydraulic fracturing fluids were detected in any of the analyzed groundwater samples.
According to a study performed by a lecturer at the State University of New York, Oneonta, nearly two percent of fracked gas wells have the potential to cause groundwater contamination.
An article by Tom Myers, a researcher from Reno, Nevada, in the journal Ground Water reported that hydraulic fracturing fluids under pressure can migrate upward through available crevices and reach shallow drinking-water aquifers in as little as three years. Myers is an independent consultant who has worked for conservation groups and governments. Myers was hired by Catskill Mountainkeeper, a New York-based environmental group that opposes fracking, and The Park Foundation in Ithaca, which offers a variety of grants. Terry Engelder, professor of geosciences at The Pennsylvania State University in University Park, said that the computer models used by Myers contain errors.
A 2008 investigation of benzene contamination in Colorado and Wyoming led some EPA officials to suggest hydraulic fracturing as a culprit.
Environmental group Riverkeeper presented a report to the EPA of over 100 cases of contamination. It has published a report of various environmental impacts using reports from federal and state regulators.
Well blowouts and spills of fracturing fluids 
A well blowout in Clearfield County, Pennsylvania on June 3, 2010, sent more than 35,000 gallons of hydraulic fracturing fluids into the air and onto the surrounding landscape in a forested area. Campers were evacuated and the company EOG Resources and the well completion company C.C. Forbes were ordered to cease all operations in the state of Pennsylvania pending investigation. The Pennsylvania Department of Environmental Protection called it a "serious incident".
Natural gas drilling and seismic events 
Injection of fluid into subsurface geological structures, such as faults and fractures, reduces the effective normal stress acting across these structures. If sufficient shear stress is present, the structure may slip in shear and generate seismic events over a range of magnitudes; natural gas drilling may have caused earthquakes in North Texas. Subsidence is not directly caused by hydraulic fracturing but may occur after considerable production of oil or ground water. Subsidence occurs over reservoirs whether they have been subject to hydraulic fracturing or not because it is a result of producing fluids from the reservoir and lowering the reservoir pore pressure. The subsidence process can be associated with some seismicity. Reports of minor tremors of no greater than 2.8 on the Richter scale were reported on June 2, 2009 in Cleburne, Texas, the first in the town's 140-year history.
Fracking connected to deep well waste water disposal has been banned in Arkansas due to the risk of contaminating aquifers if the earthquakes it induced continued. The U.S. Geological Survey is working on ways to head off quakes from wastewater wells.
Air and health 
Many particulates and chemicals can be released into the atmosphere during the process of hydraulic fracturing, such as sulfuric oxide, nitrous oxides, volatile organic compounds (VOC), benzene, toluene, diesel fuel, hydrogen sulfide which can have serious health implications. A study conducted between August 2011 and July 2012 as part of Earthworks’ Oil & Gas Accountability Project (OGAP) found chemical contaminants in the air and water of rural communities affected by the Shale extraction process in central New York and Pennsylvania. The study found disproportionately high numbers of adverse health effects in children and adults in those communities.
A potential hazard that is commonly overlooked is the venting of bulk sand silos directly to atmosphere. When they are being filled, or emptied during the fracture job, a fine cloud of silica particulate will be vented directly into atmosphere. This dust has the potential to travel many kilometers on the wind directly into populated areas. While the immediate personnel are wearing personal protective equipment, other people in the area of a well fracture can potentially be exposed.
A 2012 study out of Cornell's College of Veterinary Medicine by Robert Oswald, a professor of molecular medicine at Cornell's College of Veterinary Medicine, and veterinarian Michelle Bamberger, DVM, soon to be published in 'New Solutions: A Journal of Environmental and Occupational Health Policy,' suggests that hydraulic fracking is sickening and killing cows, horses, goats, llamas, chickens, dogs, cats, fish and other wildlife, as well as humans. The study covered cases in Colorado, Louisiana, New York, Ohio, Pennsylvania and Texas. The case studies include reports of sick animals, stunted growth, and dead animals after exposure to hydraulic fracturing spills from dumping of the fluid into streams and from workers slitting the lining of a wastewater impoundment (evaporation ponds) so that it would drain and be able to accept more waste. The researchers stated that it was difficult to assess health impact because of the industry's strategic lobbying efforts that resulted in legislation allowing them to keep the proprietary chemicals in the fluid secret, protecting them from being held legally responsible for contamination. Bamberger stated that if you don't know what chemicals are, you can't conduct pre-drilling tests and establish a baseline to prove that chemicals found postdrilling are from hydraulic fracturing. The researchers recommended requiring disclosure of all hydraulic fracturing fluids, that nondisclosure agreements not be allowed when public health is at risk, testing animals raised near hydraulic fracturing sites and animal products (milk, cheese, etc.) from animal raised near hydraulic fracturing sites prior to selling them to market, monitoring of water, soil and air more closely, and testing the air, water, soil and animals prior to drilling and at regular intervals thereafter.
Workplace safety 
The EPA states in their Hydraulic Fracturing Study Plan (2011) that the exposure to hydraulic fracturing chemicals in an occupational setting needs to be examined to determine the acute and chronic effects on health. The exposure risks such as “transport, mixing, delivery, and potential accidents” have not been properly assessed (p. 57). A study by National Institute for Occupational Safety and Health, concluded that an inhalation health hazard existed for workers exposed to crystalline silica at the evaluated hydraulic fracturing sites. NIOSH notified company representatives of these findings and provided reports with recommendations to control exposure to crystalline silica. NIOSH recommended that all hydraulic fracturing sites evaluate their operations to determine the potential for worker exposure to crystalline silica and implement controls as necessary to protect workers. Hydraulic fracturing also affects individuals in close proximity to the activity, like the case previously discussed about the nurse who became ill after exposure from treating a hydraulic fracturing worker (Frankowski, 2008).
In September 2010, a lawsuit was filed in Pennsylvania alleging that Southwestern Energy Company contaminated aquifers through a defective cement casing in the well. In June 2011, Northeast Natural Energy sued the town of Morgantown, West Virginia, for its ban on hydraulic fracturing in the Marcellus Shale within a mile of the town's borders. The ban had been initiated to protect the municipal water supply as well as the town's inhabitants, in the absence at the state level of regulations specific to hydraulic fracturing. There have been other cases as well. After court cases concerning contamination from hydraulic fracturing are settled, the documents are sealed, and information regarding contamination is not available to researchers or the general public. While the American Petroleum Institute deny that this practice has hidden problems with gas drilling, others believe it has and could lead to unnecessary risks to public safety and health.
The amount of proposed regulatory legislation related to hydraulic fracturing has dramatically increased within state legislatures since 2005. This is in part due to the fact hydraulic fracturing has started in areas in which residents are unfamiliar with natural gas operations. The majority of the proposed bills specifically address one aspect of natural gas drilling, for example wastewater treatment, though some are more comprehensive and consider multiple regulatory concerns.
Federal versus state regulation debate 
There is discussion regarding whether control of hydraulic fracturing should be at the state or federal level. Advocates of state level control of energy sources (e.g., oil, gas, wind and solar), argue that a state approach allows each state to create regulations and review processes that fit the states' particular geology, ecology and citizen concerns. Critics say that this would create a patchwork of inconsistent regulations. They also note that the components and consequences of energy development (e.g., emissions, commerce, wastewater, earthquakes, and radiation) may cross states lines, and argue that regulations need to consider the overall impact on all states. This would require regulation at the federal level. Local and state governments may also lack resources to initiate and defend against corporate legal action related to hydraulic fracturing.
Those supporting federal regulation think that it will provide more consistent, uniform standards. They say that there is a need for national environment and public health standards, including those related to water and air pollution (e.g., public disclosure of chemicals used in hydraulic fracturing, protection of drinking water sources, and control of air pollutants). A compromise approach called, "cooperative federalism" has been proposed for hydraulic fracturing. This approach has been used for coal since 1977. In this approach, the federal government sets baseline standards rather than detailed specifications, which allows states more flexibility in how they meet the standards. It would require the government to remove the regulatory exemptions for hydraulic fracturing (e.g., the Energy Policy Act of 2005, which exempted oil and gas producers from certain requirements of the Safe Drinking Water Act), and develop a comprehensive set of regulations for the industry.
The EPA and the industry group the American Petroleum Institute each provided grants to fund the organization State Review of Oil and Gas Environmental Regulations (STRONGER), to promote better state oversight of oil and gas environmental issues. The organization, at the invitation of various states, reviews their oil and gas environmental regulations in general, and hydraulic fracturing regulations in particular, and recommends improvements. As of 2013, STRONGER has reviewed hydraulic fracturing regulations in six states: Arkansas, Colorado, Louisiana, Ohio, Oklahoma, and Pennsylvania (reviews available on the STRONGER website).
On August 7, 1997, the Eleventh Circuit Court ordered the United States Environmental Protection Agency to reevaluate its stance on hydraulic fracturing based on a lawsuit brought by the Legal Environmental Assistance Foundation. Up until that decision, the EPA deemed that hydraulic fracturing did not fall under the rules in the Safe Drinking Water Act. While the impact of this decision was localized to Alabama, it forced the EPA to evaluate its oversight responsibility under the Safe Drinking Water Act for hydraulic fracturing. In 2004, the EPA released a study that concluded the threat to drinking water from hydraulic fracturing was “minimal” and the Energy Policy Act of 2005 exempted fractured wells from being re-classified as injection wells, which would place them under federal regulation under the Safe Drinking Water Act. which was originally intended to regulate disposal wells. The Energy Policy Act of 2005 did not exempt fracturing wells when diesel fuel is used as a component in the fracturing fluid. Some US House members have petitioned the EPA to take a broad interpretation of the definition of "diesel fuel" in order to increase the agency's regulatory power over hydraulic fracturing. They argue that the intent of the current limitation is not to prevent the use of a small subset of diesel compounds, but rather a safety measure to decrease the probability of accidental groundwater contamination with toxic BTEX chemicals (benzene, toluene, ethylbenzene and xylenes) that are present in diesel compounds Congress has been urged to repeal the 2005 regulatory exemption under the Energy Policy Act of 2005. The FRAC Act, introduced in June 2009, would eliminate the exemption and might allow producing wells to be reclassified as injection wells placing them under federal jurisdiction in states without approved UIC programs.
In November 2012, the Centers for Disease Control and Prevention was considering to study a potential link between fracturing and drinking water contamination. Republican House energy leaders advised Department of Health and Human Services (HHS) Secretary Kathleen Sebelius to be cautious in the study. They argued the study, if not properly done, could hinder job growth. They worried that the study could label naturally occurring substances in groundwater as contaminants, that the CDC would limit hydraulic fracturing in the interest of public health, and that the "scientific objectivity of the [HHS] [wa]s being subverted" as the CDC was considering whether or not to study the question.
Environmental Protection Agency Administrator Lisa Jackson said the EPA would use its power to protect residents if drillers endangered water supplies and state and local authorities did not take action.
Fracturing Responsibility and Awareness of Chemicals Act 
Congress has been urged to repeal the 2005 regulatory exemption under the Energy Policy Act of 2005 by supporting The FRAC Act, introduced in June 2009, but has so far refused. In June 2009 two identical bills named the Fracturing Responsibility and Awareness of Chemicals Act were introduced to both the United States House and the Senate. The House bill was introduced by representatives Diana DeGette, D-Colo., Maurice Hinchey D-N.Y., and Jared Polis, D-Colo. The Senate version was introduced by senators Bob Casey, D-Pa., and Chuck Schumer, D-N.Y. These bills are designed to amend the Safe Drinking Water Act. This would allow the Environmental Protection Agency to regulate hydraulic fracturing that occurs in states which have not taken primacy in UIC regulation. The bill required the energy industry to reveal what chemicals are being used in the sand-water mixture. The 111th United States Congress adjourned on January 3, 2011, without taking any significant action on the FRAC Act. The FRAC Act was re-introduced in both houses of the 112th United States Congress. In the Senate, Sen. Bob Casey (D-PA) introduced S. 587 on March 15, 2011. In the House, Rep. Diana DeGette (D-CO) introduced H.R. 1084 on March 24, 2011. As of March 2012 Congress had not yet passed either of The FRAC Act bills. The oil and gas industry contributes heavily to campaign funds.
Federal lands 
In May 2012, the United States Department of Interior released updated regulations on fracking, for wells on federal lands. However, Guggenheim Washington Research Group found that only about 5% of the shale wells drilled in the past 10 years were on federal land.
Voluntary disclosure of additives 
In April 2011, the Ground Water Protection Council, in conjunction with the industry, began releasing well-by-well lists of hydraulic fracturing chemicals at . Disclosure is still on a voluntary basis; companies are still not required to provide information about their hydraulic fracturing techniques and fluids that they consider to be proprietary. Lists do not include all substances used; a complete listing of the specific chemical formulation of additives used in hydraulic fracturing operations is still not currently made available to landowners, neighbors, local officials, or health care providers, let alone the general public. This practice is under scrutiny. Two studies released in 2009, one by the U.S. Department of Energy and the other released by the Ground Water Protection Council, discuss hydraulic fracturing safety concerns. Chemicals which can be used in the fracturing fluid include kerosene, benzene, toluene, xylene, and formaldehyde.
Notable omissions 
Lists provided by companies do not include many radioactive tracers used in hydraulic fracturing, such as Antimony-121, Antimony-122, Antimony-123, Antimony-124, Antimony-125, Antimony-126, Antimony-127, Chromium-51, Cobalt-57, Cobalt-58, Cobalt-60, Gold-198, Iodine-127, Iodine-128, Iodine-129, Iodine-130, Iodine-131 (one of the most commonly named in patents of the process, with a half life of 8 days), Iridium-192, Iron-59, Krypton-85, Lanthanum-140, Potassium-39 (activated to Potassium-40), Potassium-41 (activated to Potassium-42), Potassium-43, Rubidium-86, Scandium-45, Scandium-46, Scandium-47, Scandium-48, Silver-110, Strontium-85, Xenon-133, Zinc-65, and Zirconium-95. Several are typically combined and injected together. Their half lives range from 40 hours (Lanthanum-140) to 10.8 years (Krypton-85).
State and local 
In the US, some states have introduced legislation that limits the ability of municipalities to use zoning to protect citizens from exposure to pollutants from hydraulic fracturing by protecting residential areas. For instance, in Pennsylvania, the new Marcellus Shale Law (House Bill 1950) requires all municipalities to allow Marcellus Shale well drilling in all zoning districts, including residential, and allow water and wastewater pits in all zoning district, including residential. Compressor stations must be allowed in industrial and agricultural zoning districts, and gas processing plants allowed in industrial zoning districts. Municipalities are no longer permitted to limit the hours of operation of gas related activities. Gas pipelines must be allowed in all zoning districts. Similar laws have been created in Ohio, and New York, Colorado, and Texas are battling over related legislation. Pennsylvania's Marcellus Shale Law (House Bill 1950) also contains a provision that allows doctors in Pennsylvania access to the list of chemicals in hydraulic fracturing fluid in emergency situations only, and forbids them from ever discussing this information with their patients.
In May 2012 the California Senate defeated a bill, introduced by state Sen. Fran Pavley (D-Agoura Hills), requiring drillers to notify local property owners and water authorities in advance that hydraulic fracturing was going to occur, and requiring the testing of groundwater before and after the hydraulic fracturing to determine whether contamination had occurred. Pavley said that this monitoring and reporting approach would help to address citizens' concerns. The state Senate defeated the bill in a bipartisan 18-17 vote.
Governor Martin O'Malley has issued a hold on applications to drill in western Maryland until the completion of a three-year study of hydraulic fracturing's environmental impacts, thus creating a "de facto moratorium" on Hydraulic fracturing. Del. Heather Mizeur plans to introduce a bill formally banning hydraulic fracturing in Maryland until state officials can determine whether it can be done without harming drinking water or the environment. The gas industry has refused to fund the three-year study and opposed a bill sponsored by Mizeur to fund the study with fees on gas drilling leases. The industry has objected to paying for any studies unless it receives guarantees that it will eventually be able to drill for gas.
New York 
The New York State assembly voted 93 to 43, 30 November 2010, to place a moratorium or freeze on hydraulic fracturing to give the state more time to undertake safety and environmental concerns.
In September 2012, the Cuomo administration decided to wait until it completes a review of the potential public health effects of hydraulic fracturing before it allows high-volume hydraulic fracturing in New York. State legislators, medical societies and health experts pressed Joseph Martens, commissioner of the State Department of Environmental Conservation, for an independent review of the health impacts of hydraulic fracturing by medical experts before any regulations are made final and drilling is allowed to start. Martens rejected commissioning an outside study. Instead, he appointed the health commissioner, Dr. Nirav Shah, to assess the department’s analysis of the health effects closely and said Shah could consult qualified outside experts for his review.
Municipal Level 
At the municipal level, some towns and cities in central New York state have moved to regulate drilling by hydraulic fracturing and its attendant effects, either by banning it within municipal limits, maintaining the option to do so in the future, or banning wastewater from the drilling process from municipal water treatment plants.
New York City. The New York City watershed includes a large area of the Marcellus shale formation. The NYC Dept. of Environmental Protection's position: "While DEP is mindful of the potential economic opportunity that this represents for the State, hydraulic fracturing poses an unacceptable threat to the unfiltered water supply of nine million New Yorkers and cannot safely be permitted with the New York City watershed."
Niagara Falls. Niagara Falls' City Council approved an ordinance that prohibits natural gas extraction in Niagara Falls, as well as the "storage, transfer, treatment or disposal of natural gas exploration and production wastes." Elected officials there said that they didn't want their citizens, who experienced the Love Canal toxic waste crisis firsthand, to be guinea pigs for hydraulic fracturing, the new technology used in gas drilling operations. City council member, Glenn Choolokian said, “We won’t let the temptation of millions of dollars in reward for out-of-town companies, corporations and individuals to be the driving force that puts the health and lives of our children and families at risk from the dangers of hydraulic fracturing and its toxic water. I will not take part in bringing another Love Canal to the City of Niagara Falls.”“Our once great city and all the families of Niagara Falls have been through so much over the years. With Love Canal alive in our memories we aren’t going to allow another environmental tragedy to happen in our city, not today, not ever,” said Glenn Choolokian. Council Chairman Sam Fruscione said he was against selling out future generations of children for corporate greed. Rita Yelda of Food and Water Watch, pointed out that pollutants don't only affect Niagara's citizens, but those in communities downstream as well.
On May 24, 2012, House of Representatives of Ohio passed Senate Bill 315 regulating oil and gas drilling, including hydraulic fracturing. The bill requires companies to test water wells within 1,500 feet (460 m) of proposed drill sites and to report the fluids and chemicals used while drilling and fracking, except for those considered proprietary. Companies will also be required to track wastewater injected into disposal wells. According to John Funk of The Plain Dealer, the bill does not require complete disclosure of all chemicals used during drilling and hydraulic fracturing, and only requires any disclosure of chemicals after the well is already drilled. Proprietary formulas are protected. The Ohio Department of Natural Resources is allowed up to 60 days after drilling to post the chemicals on its web site. Opponents had wanted the bill to require chemicals to be disclosed before drilling so that citizens could have their wells tested for baseline levels of contaminants. The Ohio Senate also removed the requirement for disclosure of drilling lubricants in the space below the local water table but above its final depth. The bill denies the public the right to appeal a drilling permit, and permits do not require public notices. The bill allows doctors to reveal the formulate only to the patient, family and other doctors involved solely for the purpose of treatment, not legal or other proceedings.
Marcellus Shale Drilling Permits 
The Marcellus Center at Pennsylvania State University reports that the number of permits issued for wells has increased from 122 in 2007 to 3249 in 2011. The Marcellus Center has posted an animated map of the proliferation of Marcellus Shale Drilling Permits in Pennsylvania.
In November 2012 the PA DEP was again accused of withholding information about chemicals from hydraulic fracturing fluid that were found in residents' drinking water. The DEP had previously failed to notify residents about fracking related contamination events.
The Marcellus Shale Law (House Bill 1950) 
The Marcellus Shale Law (House Bill 1950) was signed on February 14, 2012, by Governor Tom Corbett. Despite warnings from the EPA about the safety of wastewater, the law changes the zoning laws applicable to Marcellus Shale Well Drilling. The law was slated to take effect in April 2012, but legal challenges from a growing group of Pennsylvania municipalities and organizations led Commonwealth Senior Judge Keith Quigley to order that the implementation of parts of Act 13 be delayed for 120 days. Some of its provisions are that all municipalities must now allow Marcellus Shale well drilling (in all zoning districts, including residential and may not limit hours of operation), water and wastewater pits (in all zoning district, including residential), compressor stations (in industrial and agricultural zoning districts and may not limit hours of operation), gas processing plants (in industrial zoning districts and cannot limit hours of operation), and gas pipelines (in all zoning districts, including residential). The law helps pave the way for a new pipeline across Pennsylvania to export terminals in Maryland.
The Marcellus Shale Law (House Bill 1950) also contains a provision that allows doctors in Pennsylvania access to the list of chemicals in hydraulic fracturing fluid in emergency situations, but forbids them from discussing this information with their patients. This provision was added during the last revisions of the bill. Specifically, the bill reads that, "(11) If a health professional determines that a medical emergency exists and the specific identity and amount of any chemicals claimed to be a trade secret or confidential proprietary information are necessary for emergency treatment, the vendor, service provider or operator shall immediately disclose the information to the health professional upon a verbal acknowledgment by the health professional that the information may not be used for purposes other than the health needs asserted and that the 'health professional shall maintain the information as confidential.' The vendor, service provider or operator may request, and the health professional shall provide upon request, a written statement of need and a confidentiality agreement from the health professional as soon as circumstances permit, in conformance with regulations promulgated under this chapter." The bill also says that vendors, service providers, and operators cannot be held responsible for inaccuracy in information that is provided to them, nor do they have to reveal the identities of chemicals that are not disclosed to them, that were not intentionally added to the hydraulic fracturing fluid, that are accidentally present in trace amounts, or are a product of a chemical reaction or process that occurs within the fluid.
The US Environmental Protection Agency is increasing its oversight regarding investigations of hydraulic fracturing in Pennsylvania, which is currently under the administration of pro-drilling Governor Tom Corbett. The New York Times reported that regulations are lax in Pennsylvania. The oil and gas industry is generally left to police itself in the case of accidents. Unannounced inspections are not made by regulators: the companies report their own spills, and create their own remediation plans. A recent review of the state-approved plans found them to appear to be in violation of the law. There are signs of regulatory capture. Corbett received over a million dollars in campaign contributions from the oil and gas industry. Ronald Krancer, father of 2012 Pennsylvania DEP Secretary Michael Krancer, donated $25,000 to the State Republican Committee the day before his son was confirmed as the new Department of Environmental Protection Secretary. In addition, Michael Krancer's father contributed $150,000 to Governor Corbett's campaign, tens of thousands to GOP Bob Asher's political action committee and at least $125,000 to the state Republican Party since 2008.
Although there has been no hydraulic fracking in the state, the Vermont House of Representatives passed a moratorium on hydraulic fracturing in February 2012, and on May 17, 2012 Governor Peter Shumlin (Democrat) signed the law making Vermont the first state to ban hydraulic fracturing. On Friday, May 4, 2012, the Vermont legislature voted 103-36 to ban hydraulic fracturing in the state. The bill also requires the state's regulations be revised to prohibit injection well operators from accepting oil and natural gas drilling waste water from out of state.
On June 8, 2010 the Wyoming Oil and Gas Conservation Commission voted to require full disclosure of the hydraulic fracturing fluids used in natural gas exploration. This may aid in tracking pollutants that have migrated from hydraulically fractured gas wells.
Media and public relations 
The opposition against fracking activities in local townships has led companies to adopt a variety of public relations measures to assuage fears about fracking, including the admitted use of "military tactics to counter drilling opponents". At a conference where public relations measures were discussed, a senior executive at Anadarko Petroleum was recorded on tape saying, "Download the US Army / Marine Corps Counterinsurgency Manual, because we are dealing with an insurgency", while referring to fracking opponents. Matt Pitzarella, spokesman for the most important fracking company in Pennsylvania, Range Resources, also told other conference attendees that Range employed psychological warfare operations veterans. According to Pitzarella, the experience learnt in the Middle East has been valuable to Range Resources in Pennsylvania, when dealing with emotionally-charged township meetings and advising townships on zoning and local ordinances dealing with fracking. Furthermore, in a February 2012 campaign speech, Rick Santorum, a candidate for the 2012 Republican Party presidential nomination, referred to those objecting to hydraulic fracturing as environmental terrorists.
See also 
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- Shale gas in the United States
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Further reading 
- Wilber, Tom (2012). Under the Surface: Fracking, Fortunes, and the Fate of the Marcellus Shale. Ithaca, NY: Cornell University Press. ISBN 9780801450167.
||This article's use of external links may not follow Wikipedia's policies or guidelines. (August 2012)|
- EPA: Hydraulic fracturing (United States)
- EPA Opens Public Hearings on Health and Environmental Impact of Hydraulic Fracturing — video report by Democracy Now!
- FracTracker: Maps, data, and articles from news, government, industry, and academic sources.
- Global Research (Canada)
- NYC Department of Environmental Protection: Natural Gas Drilling In Marcellus Shale
- SavetheWaterTable.org — Organization dedicated to saving the aquifer in the face of fracking
- Shale Shock Upstate New York organization dedicated to education, outreach, and organizing resistance against drilling in the Marcellus Shale.
- Treatment of Fracture Stimulated Wells Publication discussing the process of testing and treating fracture stimulated wells.
- Energy: The Pros and Cons of Shale Gas Drilling a 60 Minutes report on fracing by CBS News, featuring Chesapeake Energy, originally broadcast on November 14, 2010
- Kaplan, Thomas (November 25, 2011). "Hydrofracking Debate Spurs Huge Spending by Industry". The New York Times. ISSN 0362-4331. Retrieved November 28, 2011.
- Natural Gas and the News; Most messages on fracking ‘brought to you by our sponsors’ from Fairness and Accuracy in Reporting February 2012
- Pressconnects.com Marcellus Shale — Newspaper website covering Hydraulic fracturing & Marcellus Shale
- Saefong, Myra P. (December 2, 2011). "Shale gas gives rise to era of energy independence". MarketWatch. Retrieved December 4, 2011.