GASLAND
Politics and public policy
To control the hydraulic fracturing industry, some governments are developing legislation and some municipalities are developing local zoning limitations.[217] In 2011, France became the first nation to ban hydraulic fracturing.[10][11] Some other countries have placed a temporary moratorium on the practice.[218] The US has the longest history with hydraulic fracturing, so its approach to hydraulic fracturing may be modeled by other countries.[86] In August 2013 the Church of England, in an official statement, criticized those who advocate “blanket opposition” to fracking[219]The considerable opposition against hydraulic fracturing activities in local townships has led companies to adopt a variety of public relations measures to assuage fears about hydraulic fracturing, 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 hydraulic fracturing opponents. Matt Pitzarella, spokesman for Range Resources also told other conference attendees that Range employed psychological warfare operations veterans. According to Pitzarella, the experience learned 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 hydraulic fracturing.[220][221]
Police officers have recently been forced, however, to deal with intentionally disruptive and even potentially violent opposition to oil and gas development. In March 2013, ten people were arrested [222] during an "anti-fracking protest" near New Matamoras, Ohio, after they illegally entered a development zone and latched themselves to drilling equipment. In northwest Pennsylvania, there was a drive-by shooting at a well site, in which an individual shot two rounds of a small-caliber rifle in the direction of a drilling rig, just before shouting profanities at the site and fleeing the scene.[223] And in Washington County, Pa., a contractor working on a gas pipeline found a pipe bomb that had been placed where a pipeline was to be constructed, which local authorities said would have caused a “catastrophe” had they not discovered and detonated it.[224]
Media coverage
Josh Fox's 2010 Academy Award nominated film Gasland became a center of opposition to hydraulic fracturing of shale. The movie presented problems with ground water contamination near well sites in Pennsylvania, Wyoming, and Colorado.[225] Energy in Depth, an oil and gas industry lobbying group, called the film's facts into question.[226] In response, a rebuttal of Energy in Depth's claims of inaccuracy was posted on Gasland's website.[227] The Director of the Colorado Oil and Gas Conservation Commission (COGCC) offered to be interviewed as part of the film if he could review what was included from the interview in the final film but Fox declined the offer.[228] Exxon Mobil, Chevron Corporation and ConocoPhillips aired advertisements during 2011 and 2012 that claim to describe the economic and environmental benefits of natural gas and argue hydraulic fracturing is safe.[229]The film Promised Land, starring Matt Damon, takes on hydraulic fracturing.[230] The gas industry has made plans to counter the film's criticisms of hydraulic fracturing with informational flyers, and Twitter and Facebook posts.[229]
On January 22, 2013 Phelim McAleer, journalist and filmmaker, released a crowdfunded[231] documentary called FrackNation as a response to Gasland. FrackNation premiered on Mark Cuban's AXS TV. The premiere corresponded with the release of Promised Land.[232]
Hydraulic fracturing is the fracturing of rock by a pressurized liquid. Some hydraulic fractures form naturally—certain veins or dikes are examples. Induced hydraulic fracturing or hydrofracturing, commonly known as fracking, is a technique in which typically water is mixed with sand and chemicals, and the mixture is injected at high pressure into a wellbore to create small fractures (typically less than 1mm), along which fluids such as gas, petroleum, uranium-bearing solution,[1] and brine water may migrate to the well. Hydraulic pressure is removed from the well, then small grains of proppant (sand or aluminium oxide) hold these fractures open once the rock achieves equilibrium. The technique is very common in wells for shale gas, tight gas, tight oil, and coal seam gas[2][3] and hard rock wells. This well stimulation is usually conducted once in the life of the well and greatly enhances fluid removal and well productivity, but there has been an increasing trend towards multiple hydraulic fracturing as production declines. A different technique where only acid is injected is referred to as acidizing.
The first experimental use of hydraulic fracturing was in 1947, and the first commercially successful applications were in 1949. George P. Mitchell is considered by some the modern "father of fracking" when he successfully applied it to the Barnett Shale in the 1990s.[4] As of 2010, it was estimated that 60% of all new oil and gas wells worldwide were being hydraulically fractured.[5] As of 2012, 2.5 million hydraulic fracturing jobs have been performed on oil and gas wells worldwide, more than one million of them in the United States.[6][7] Uranium Energy Corporation is planning to use hydraulic fracturing to mine uranium. Fracking for uranium involves injecting oxygenated water (to increase solubility) to dissolve the uranium, then pumping the solution back up to the surface.[1]
Proponents of hydraulic fracturing point to the economic benefits from the vast amounts of formerly inaccessible hydrocarbons the process can extract.[8] Opponents point to potential environmental impacts, including contamination of ground water, depletion of fresh water, risks to air quality, noise pollution, the migration of gases and hydraulic fracturing chemicals to the surface, surface contamination from spills and flow-back, and the health effects of these.[9] For these reasons hydraulic fracturing has come under international scrutiny, with some countries suspending or banning it.[10][11] However, some of those countries, including most notably the United Kingdom,[12] have recently lifted their bans, choosing to focus on regulations instead of outright prohibition. The 2013 draft EU-Canada trade treaty includes language outlawing any "breach of legitimate expectations of investors" which may occur if revoking drilling licences of Canada-registered companies in the territory of the European Union after the treaty comes into force.[13] Under Chapter 11 of the existing North American Free Trade Agreement, private companies can sue governments when new laws reduce expected profits from existing contracts.[14]
Main articles: Proppants and fracking fluids and List of additives for hydraulic fracturing
High-pressure fracture fluid is injected into the wellbore, with the pressure above the fracture gradient of the rock. The two main purposes of fracturing fluid is to extend fractures, add lubrication, change gel strength and to carry proppant into the formation, the purpose of which is to stay there without damaging the formation or production of the well. Two methods of transporting the proppant in the fluid are used – high-rate and high-viscosity. High-viscosity fracturing tends to cause large dominant fractures, while high-rate (slickwater) fracturing causes small spread-out micro-fractures.[citation needed]This fracture fluid contains water-soluble gelling agents (such as guar gum) which increase viscosity and efficiently deliver the proppant into the formation.[63]
A proppant is a material that will keep an induced hydraulic fracture open, during or following a fracturing treatment, and can be gel, foam, or slickwater-based. Fluids make tradeoffs in such material properties as viscosity, where more viscous fluids can carry more concentrated proppant; the energy or pressure demands to maintain a certain flux pump rate (flow velocity) that will conduct the proppant appropriately; pH, various rheological factors, among others. Types of proppant include silica sand, resin-coated sand, and man-made ceramics. These vary depending on the type of permeability or grain strength needed. The most commonly used proppant is silica sand, though proppants of uniform size and shape, such as a ceramic proppant, is believed to be more effective. Due to a higher porosity within the fracture, a greater amount of oil and natural gas is liberated.[68]
The fracturing fluid varies in composition depending on the type of fracturing used, the conditions of the specific well being fractured, and the water characteristics. A typical fracture treatment uses between 3 and 12 additive chemicals.[56] Although there may be unconventional fracturing fluids, the more typically used chemical additives can include one or more of the following:
- Acids—hydrochloric acid or acetic acid is used in the pre-fracturing stage for cleaning the perforations and initiating fissure in the near-wellbore rock.[66]
- Sodium chloride (salt)—delays breakdown of the gel polymer chains.[66]
- Polyacrylamide and other friction reducers—minimizes the friction between fluid and pipe, thus allowing the pumps to pump at a higher rate without having greater pressure on the surface.[66]
- Ethylene glycol—prevents formation of scale deposits in the pipe.[66]
- Borate salts—used for maintaining fluid viscosity during the temperature increase.[66]
- Sodium and potassium carbonates—used for maintaining effectiveness of crosslinkers.[66]
- Glutaraldehyde—used as disinfectant of the water (bacteria elimination).[66]
- Guar gum and other water-soluble gelling agents—increases viscosity of the fracturing fluid to deliver more efficiently the proppant into the formation.[63][66]
- Citric acid—used for corrosion prevention.
- Isopropanol—increases the viscosity of the fracture fluid.[66]
Typical fluid types are:
- Conventional linear gels. These gels are cellulose derivatives (carboxymethyl cellulose, hydroxyethyl cellulose, carboxymethyl hydroxyethyl cellulose, hydroxypropyl cellulose, methyl hydroxyl ethyl cellulose), guar or its derivatives (hydroxypropyl guar, carboxymethyl hydroxypropyl guar) based, with other chemicals providing the necessary chemistry for the desired results.
- Borate-crosslinked fluids. These are guar-based fluids cross-linked with boron ions (from aqueous borax/boric acid solution). These gels have higher viscosity at pH 9 onwards and are used to carry proppants. After the fracturing job the pH is reduced to 3–4 so that the cross-links are broken and the gel is less viscous and can be pumped out.
- Organometallic-crosslinked fluids zirconium, chromium, antimony, titanium salts are known to crosslink the guar based gels. The crosslinking mechanism is not reversible. So once the proppant is pumped down along with the cross-linked gel, the fracturing part is done. The gels are broken down with appropriate breakers.[63]
- Aluminium phosphate-ester oil gels. Aluminium phosphate and ester oils are slurried to form cross-linked gel. These are one of the first known gelling systems.
Hydraulic fracturing has been seen as one of the key methods of extracting unconventional oil and gas resources. According to the International Energy Agency, the remaining technically recoverable resources of shale gas are estimated to amount to 208 trillion cubic metres (208,000 km3), tight gas to 76 trillion cubic metres (76,000 km3), and coalbed methane to 47 trillion cubic metres (47,000 km3). As a rule, formations of these resources have lower permeability than conventional gas formations. Therefore, depending on the geological characteristics of the formation, specific technologies (such as hydraulic fracturing) are required. Although there are also other methods to extract these resources, such as conventional drilling or horizontal drilling, hydraulic fracturing is one of the key methods making their extraction economically viable. The multi-stage fracturing technique has facilitated the development of shale gas and light tight oil production in the United States and is believed to do so in the other countries with unconventional hydrocarbon resources.[8]
The National Petroleum Council estimates that hydraulic fracturing will eventually account for nearly 70% of natural gas development in North America.[82] Hydraulic fracturing and horizontal drilling apply the latest technologies and make it commercially viable to recover shale gas and oil. In the United States, 45% of domestic natural gas production and 17% of oil production would be lost within 5 years without usage of hydraulic fracturing.[83]
A number of studies related to the economy and fracking, demonstrates a direct benefit to economies from fracking activities in the form of personnel, support, ancillary businesses, analysis and monitoring. Typically the funding source of the study is a focal point of controversy.[84] Most studies are either funded by mining companies or funded by environmental groups, which can at times lead to at least the appearance of unreliable studies.[84] A study was performed by Deller & Schreiber in 2012, looking at the relationship between non-oil and gas mining and community economic growth. The study concluded that there is an impact on income growth; however, researchers found that mining does not lead to an increase in population or employment.[84] The actual financial impact of non-oil and gas mining on the economy is dependent on many variables and is difficult to identify definitively.
Main article: Environmental impact of hydraulic fracturing
Hydraulic fracturing has raised environmental concerns and is challenging the adequacy of existing regulatory regimes.[85] These concerns have included ground water contamination, risks to air quality, migration of gases and hydraulic fracturing chemicals to the surface, mishandling of waste, and the health effects of all these, as well as its contribution to raised atmospheric CO2 levels by enabling the extraction of previously-sequestered hydrocarbons.[9][56][69] Because hydraulic fracturing originated in the United States,[86] its history is more extensive there than in other regions. Most environmental impact studies have therefore taken place there.Concerns have been raised about research financed by foundations and corporations [87] that some have argued is designed to inflate or minimize the risks of development,[88] as well as lobbying by the gas industry to promote its activities.[89] Several organizations, researchers, and media outlets have reported difficulty in conducting and reporting the results of studies on hydraulic fracturing due to industry[90][91] and governmental pressure, and expressed concern over possible censoring of environmental reports.[90][92][93] A New York Times report claimed that an early draft of a 2004 EPA study discussed "possible evidence" of aquifer contamination but the final report omitted that mention.[90][94] Some have also criticized the narrowing of EPA studies, including the EPA study on hydraulic fracturing's impact on drinking water to be released in late 2014.[91][92][95] In addition, after court cases concerning contamination from hydraulic fracturing are settled, the documents are sealed, reducing the information available about contamination.[96] The American Petroleum Institute denies that this practice has hidden problems with gas drilling.[citation needed] Researchers have recommended requiring disclosure of all hydraulic fracturing fluids, testing animals raised near fracturing sites, and closer monitoring of environmental samples.[97] Many believe there is a need for more research into the environmental and health impacts of the technique.[98][99]
When petroleum crude oil is extracted and produced from onshore or offshore oil wells, raw natural gas associated with the oil is produced to the surface as well. One gas which is commonly flared is hydrogen sulfide, which is an irritant and a chemical asphyxiant that can alter both oxygen utilization and the central nervous system, according to the U.S. OSHA.[100] Excessive H2S production in previously nonsour environments are "primarily anthropogenic and caused by certain operational practices".[101] In areas of the world lacking pipelines and other gas transportation infrastructure, vast amounts of such associated gas are commonly flared as waste or unusable gas. In June 2013, the Enbridge corporation obtained an order to reject from its system crude that had high levels of sour gas.[100] Enbridge had found in one instance concentration levels of 1,200ppm.[100] The US FERC regulator sets 10ppm as a maximum for this noxious gas. A concentration 120 times as high "could cause death, or serious injuries".[100]
A Pennsylvania family was forced to abandon because of pollution of their 10-acre farm. The family was paid 750,000USD by Range Resources Corporation to depart from a more recently installed petroleum well plant, though the family was required to sign an agreement which stated that they haven't suffered nor ever will suffer any adverse medical effects from the toxic exposure.[102]
The air emissions from hydraulic fracturing are also related to methane leaks originating from wells, and emissions from the diesel or natural gas powered equipment such as compressors, drilling rigs, pumps etc.[56] Also transportation of necessary water volume for hydraulic fracturing, if done by trucks, can cause high volumes of air emissions, especially particulate matter emissions.[103] There are also reports of health problems around compressors stations[104] or drilling sites,[105] although a causal relationship was not established for the limited number of wells studied[105] and another Texas government analysis found no evidence of effects.[106]
Whether natural gas produced by hydraulic fracturing causes higher well-to-burner emissions than gas produced from conventional wells is a matter of contention. A 2012 report coauthored by researchers at the U.S. Department of Energy’s National Renewable Energy Laboratory found emissions from shale gas, when burned for electricity, were “very similar” to those from so-called “conventional well” natural gas, and less than half the emissions of coal.[107] In April 2013 the EPA lowered its estimate of how much methane gas is released to the atmosphere during the fracking process by 20 percent.[108] Some studies have found that hydraulic fracturing has higher emissions due to gas released during completing wells as some gas returns to the surface, together with the fracturing fluids. Depending on their treatment, the well-to-burner emissions are 3.5%–12% higher than for conventional gas.[85] Studies that estimate the amount of methane leakage from shale gas development and production find that leakage could be as low as less than 1% of total gas production, or as high as several percent, with most recent studies on the low end of that range.[109][110] A debate has arisen particularly around a study by professor Robert W. Howarth finding shale gas significantly worse for global warming than oil or coal.[111] Other researchers have criticized Howarth's analysis.[112][113] Howarth has responded that "The latest EPA estimate for methane emissions from shale gas falls within the range of our estimates but not those of Cathles et al., which are substantially lower."[114] The U.S. EPA has estimated the methane leakage rate to be about 2.4% – well below Howarth’s estimate. The American Gas Association, and industry trade group, calculated a 1.2% leakage rate [115] based on the EPA's latest greenhouse gas inventory, although the EPA has not publicly stated a change to its prior estimate.
Hydraulic fracturing uses between 1.2 and 3.5 million US gallons (4.5 and 13.2 Ml) of water per well, with large projects using up to 5 million US gallons (19 Ml). Additional water is used when wells are refractured.[63][116] An average well requires 3 to 8 million US gallons (11,000 to 30,000 m3) of water over its lifetime.[56][116][117][118] Back in 2008 at the beginning of the shale boom in Pennsylvania, hydraulic fracturing accounted for 650 million US gallons per year (2,500,000 m3/a) (less than 0.8%) of annual water use in the area overlying the Marcellus Shale.[117][119] The annual number of well permits, however, increased by a factor of five[120] and the number of well starts increased by a factor of over 17 from 2008 to 2011.[121] According to the Oxford Institute for Energy Studies, greater volumes of fracturing fluids are required in Europe, where the shale depths average 1.5 times greater than in the U.S.[122]
Appropriating large quantities of water for hydraulic fracturing diverts water from stream flow, water supplies for municipalities and industries such as power generation, as well as recreation and aquatic life.[123] The large volumes of water required have raised concerns about hydraulic fracturing in arid areas, such as Karoo in South Africa[86] and drought prone areas of North America.[124] It may also require water overland piping from distant sources.[117] A report by Ceres questions whether the growth of hydraulic fracturing is sustainable in Texas and Colorado. The report integrated well location and water use data from FracFocus.org with World Resources Institute's (WRI) water risk maps. Ninety-two percent of Colorado wells were in extremely high water stress regions and 51% percent of the Texas wells evaluated were in high or extremely high water stress regions. "Extremely high water stress" means that more than 80% of the available water is already allocated for agricultural, industrial and municipal water use.[1]
In Barnhart, Texas the aquifer ran dry because of industrial fracking: one landowner had 104 water wells (designed to supply fracking) dug into his land by his fracker tenants, and the population is left with little recourse for their dry taps.[125] In the Spring of 2013, new hydraulic fracturing water recycling rules were adopted in the state of Texas by the Railroad Commission of Texas. The Water Recycling Rules are intended to encourage Texas hydraulic fracturing operators to conserve water used in the hydraulic fracturing process for oil and gas wells.[126]
Recycling[85] and using carbon dioxide instead of water[127] have been proposed to reduce water consumption. While recycled flowback water cannot yet be made safe enough for drinking or growing crops, it can reused in hydraulic fracturing, though it can shorten the life of some types of equipment.[128]
There are concerns about possible contamination by hydraulic fracturing fluid both as it is injected under high pressure into the ground and as it returns to the surface.[129][130] To mitigate the impact of hydraulic fracturing to groundwater, the well and ideally the shale formation itself should remain hydraulically isolated from other geological formations, especially freshwater aquifers.[85] In 2009 state regulators from at least a dozen states have also stated that they have seen no evidence[131] of the hydraulic fracturing process polluting drinking water. In May 2011, former U.S. EPA administrator Lisa Jackson (appointed by President Barack Obama) has said on at least two occasions that there is either no proven case of direct contamination by the hydraulic fracturing process, or that the EPA has never made a definitive determination[132] of such contamination. By August 2011 there were at least 36 cases of suspected groundwater contamination due to hydraulic fracturing in the United States. In more recent congressional testimony in April 2013, Dr. Robin Ikeda, Deputy Director of Noncommunicable Diseases, Injury and Environmental Health at the CDC listed several sites where EPA had documented contamination.[133] In several cases EPA has determined that hydraulic fracturing was likely the source of the contamination.[134][135][136][137][138][139]
While some of the chemicals used in hydraulic fracturing are common and generally harmless, some are known carcinogens.[69] A report prepared for House Democratic members Henry Waxman, Edward Markey and Diana DeGette stated that out of 2,500 hydraulic fracturing products, "more than 650 of these products contained chemicals that are known or possible human carcinogens, regulated under the Safe Drinking Water Act, or listed as hazardous air pollutants".[69] The report also shows that between 2005 and 2009, 279 products had at least one component listed as "proprietary" or "trade secret" on their Occupational Safety and Health Administration (OSHA) required material safety data sheet (MSDS). The MSDS is a list of chemical components in the products of chemical manufacturers, and according to OSHA, a manufacturer may withhold information designated as "proprietary" from this sheet. When asked to reveal the proprietary components, most companies participating in the investigation were unable to do so, leading the committee to surmise these "companies are injecting fluids containing unknown chemicals about which they may have limited understanding of the potential risks posed to human health and the environment".[69] Without knowing the identity of the proprietary components, regulators cannot test for their presence. This prevents government regulators from establishing baseline levels of the substances prior to hydraulic fracturing and documenting changes in these levels, thereby making it more difficult to prove that hydraulic fracturing is contaminating the environment with these substances.[140]
Another 2011 study identified 632 chemicals used in natural gas operations. Only 353 of these are well-described in the scientific literature. The study indicated possible long-term health effects that might not appear immediately. The study recommended full disclosure of all products used, along with extensive air and water monitoring near natural gas operations; it also recommended that hydraulic fracturing's exemption from regulation under the US Safe Drinking Water Act be rescinded.[141] Industry group Energy In Depth, a research arm of the Independent Petroleum Association of America, contends that fracking "was never granted an 'exemption' from it... How can something earn an exemption from a law that never covered or even conceived of it in the first place?”[142]
Governments are responding to questions about the contents of hydraulic fracturing fluid by requiring disclosure via government agencies and public web site. The Irish regulatory regime requires full disclosure of all additives to Ireland's Environmental Protection Agency (Ireland). The European Union also requires such disclosure.[143] In the US, the Ground Water Protection Council launched FracFocus.org, an online voluntary disclosure database for hydraulic fracturing fluids funded by oil and gas trade groups and the U.S. Department of Energy. The site has been met with some skepticism relating to proprietary information that is not included.[144][145] Some states have mandated fluid disclosure and incorporated FracFocus as the tool for disclosure.[146][147] Also in the US, FracTracker Alliance provides oil and gas-related data storage, analyses, and online and customized maps related to hydraulic fracturing on FracTracker.org.
Estimates of the amount of injected fluid returning to the surface vary. Some say approximately 15-20% of the injected fluid returns to the surface with the gas[150] and others say that in the weeks or months after gas production starts, about 30–70% of the original fracture fluid flows back to the surface with the gas, often mixed with natural formation water.[151][152] Some remains underground[150] and some may return to the surface through abandoned wells or other pathways.[153] After the frack flowback is recovered, formation water, usually brine, may continue to flow to the surface, and need treatment or disposal. These fluids, commonly known as flowback, produced water, or wastewater, are managed by underground injection, wastewater treatment and discharge, or recycling to fracture future wells.[107][152][154][155] Hydraulic fracturing can concentrate levels of uranium, radium, radon, and thorium in flowback.[156] One Duke University study reported that Marcellus [Shale] wells produce significantly less wastewater per unit gas recovered (~35%) compared to conventional natural gas wells.”[157] Treatment of produced waters may be feasible through either self-contained systems at well sites or fields or through municipal waste water treatment plants or commercial treatment facilities.[152] However, the quantity of waste water being treated, and the improper configuration of sewage plants to treat it, became an issue in Pennsylvania. When waste brine is discharged to surface waters through conventional wastewater treatment plants, the bromide in the brine usually passes through undiminished. Although not posing a health hazard by itself, in western Pennsylvania some downstream drinking water treatment plants using the surface water experienced increases in brominated trihalomethanes in 2009 and 2010. Trihalomethanes, undesirable byproducts of the chlorination process, form when the chlorine combines with dissolved organic matter in the source water, to form the trihalomethane chloroform. If bromine is present, it will substitute for some of the chlorine, forming brominated trihalomethanes. Because bromine has a higher atomic weight than chlorine, the partial conversion to brominated trihalomethanes increases the concentration by weight of total trihalomethanes.[158][159][160]
Vengosh, the co-author of a Duke University study has advised the UK to impose better environmental regulation than US if it pursues shale gas extraction.[161] Before 2011, wastewater from gas wells in Pennsylvania was processed by public sewage treatment plants, which are not equipped to remove radioactive material and are not required to test for it.[162][163] In 2010 the Pennsylvania Department of Environmental Protection (DEP) limited surface water discharges from new treatment plants to 250 mg/l chloride. This chloride limitation was designed to also limit other contaminants such as radium. Existing water treatment plants were "grandfathered," and are still allowed higher discharge concentrations. In April 2011, the DEP asked unconventional gas operators to voluntarily stop sending wastewater to the grandfathered treatment plants. The PADEP reported that the operators had complied.[164] A 2012 study by researchers from the National Renewable Energy Laboratory, University of Colorado, and Colorado State University reported a reduction in the percentage of flowback treated through surface water discharge in Pennsylvania from 2008 through 2011.[107] By late 2012, bromine concentrations had declined back to previous levels in the Monongahela River, but remained high in the Allegheny.[165] In Colorado the volume of wastewater discharged to surface streams increased from 2008 to 2011.[107] A recent Duke University study sampled water downstream from a Pennsylvania wastewater treatment facility from 2010 through Fall 2012 and found the creek sediment contained levels of radium 200 times background levels, the surface water contained high levels of chloride and bromide, and the water had the same chemical signature as rocks in the Marcellus Shale formation. The facility denied processing Marcellus waste since 2011. In May 2013 the facility signed another agreement to not accept or discharge wastewater Marcellus Shale formations until it has installed technology to remove the radiation compounds, metals and salts.[166][167]
Methane
Groundwater methane contamination is also a concern as it has adverse impact on water quality and in extreme cases may lead to potential explosion.[163][168] In 2006, over 7 million cubic feet (200,000 m3) of methane were released from a blown gas well in Clark, Wyoming and shallow groundwater was found to be contaminated.[169] A scientific study reported in the PNAS investigated concerns over fracking and well water. The study found high correlations of drilling activity and methane pollution of the drinking water.[170] Methane contamination is not always caused by hydraulic fracturing. Drilling for ordinary drinking water wells can also cause methane release. Most recent studies make use of tests that can distinguish between the deep thermogenic methane released during gas/oil drilling, and the shallower biogenic methane that can be released during water-well drilling. While both forms of methane result from decomposition, thermogenic methane results from geothermal assistance deeper underground.[171][172]According to the 2011 study of the MIT Energy Initiative, "there is evidence of natural gas (methane) migration into freshwater zones in some areas, most likely as a result of substandard well completion practices i.e. poor quality cementing job or bad casing, by a few operators."[173] 2011 studies by the Colorado School of Public Health and Duke University also pointed to methane contamination stemming from hydraulic fracturing or its surrounding process.[168][172] A study by Cabot Oil and Gas examined the Duke study using a larger sample size, found that methane concentrations were related to topography, with the highest readings found in low-lying areas, rather than related to distance from gas production areas. Using a more precise isotopic analysis, they showed that the methane found in the water wells came from both the Marcellus Shale (Middle Devonian) where hydraulic fracturing occurred, and from the shallower Upper Devonian formations.[171] A 2013 Duke study suggested that both defective cement seals in the upper part of wells and faulty steel linings within deeper layers may be allowing methane and injected fluid to seep into surface waters.[130] Abandoned gas and oil wells also provide conduits to the surface.[153] A recent Duke University study found methane concentrations six times higher and ethane concentrations were 23 times higher at residences within a kilometer of a shale gas well. Propane was also detected in 10 homes within a kilometer of drilling. The researchers reported that the methane, ethane and propane data, and new evidence from hydrocarbon and helium content, all suggested that drilling has affected the drinking water. They noted that the ethane and propane data were notable because there was no biological source of ethane and propane in the region and Marcellus gas is higher in both than are Upper Devonian gases.[174]
Hydrogen sulfide
Hydrogen sulfide (H2S, sour gas), a gas which is toxic to humans and flammable, has been detected in some fracked crude by the Enbridge corporation.[175] A paper published by the Society of Petroleum Engineers stated in 2011 that increased concentration of H2S in crude oil presents challenges such as "health and environmental risks, corrosion of wellbore, added expense with regard to materials handling and pipeline equipment, and additional refinement requirements".[101] Holubnyak et al. further state in their paper on the Bakken formation that "the causes of excessive H2S production in previously nonsour environments are primarily anthropogenic and caused by certain operational practices."Radioactivity
There are concerns about the levels of radioactivity in wastewater from hydraulic fracturing and its potential impact on public health. Tests conducted in Pennsylvania in 2009 found “no evidence of elevated radiation levels” in waterways.[176] At the time radiation concerns were not seen as a pressing issue.[176] The EPA called for more testing.[177] In 2011 The New York Times reported radium in wastewater from natural gas wells is released into Pennsylvania rivers,[163][178] and compiled a map of these wells and their wastewater contamination levels,[179] and stated that some EPA reports were never made public.[129] The Times' reporting on the issue has come under some criticism.[180][181] A 2012 study examining a number of hydraulic fracturing sites in Pennsylvania and Virginia by Pennsylvania State University, found that water that flows back from gas wells after hydraulic fracturing contains high levels of radium.[182] A recent Duke University study sampled water downstream from a Pennsylvania wastewater treatment facility from 2010 through Fall 2012 and found the creek sediment contained levels of radium 200 times background levels.[161] The surface water had the same chemical signature as rocks in the Marcellus Shale formation. The facility denied processing Marcellus waste since 2011. In May 2013 the facility signed another agreement to not accept or discharge wastewater Marcellus Shale formations until it has installed technology to remove the radiation compounds, metals and salts.[166][167] Recycling this wastewater has been proposed as a partial solution, but this approach has limitations.[183]Solid waste such as drill cuttings is also radioactive. In 2012 there were 1325 radiation alerts from all sources at dumps in Pennsylvania, up from 423 alerts in 2008. At least 1,000 of the 2012 alerts were set off by waste from gas and oil drilling hydraulic fracturing operations.[184]
Seismicity
Hydraulic fracturing routinely produces microseismic events much too small to be detected except by sensitive instruments. These microseismic events are often used to map the horizontal and vertical extent of the fracturing.[185] However, as of late 2012, there have been three instances of hydraulic fracturing, through induced seismicity, triggering quakes large enough to be felt by people: one each in the United States, Canada, and England.[186]A 2012 US Geological Survey study reported that a "remarkable" increase in the rate of M ≥ 3 earthquakes in the US midcontinent "is currently in progress", having started in 2001 and culminating in a 6-fold increase over 20th century levels in 2011. The overall increase was tied to earthquake increases in a few specific areas: the Raton Basin of southern Colorado (site of coalbed methane activity), and gas-producing areas in central and southern Oklahoma, and central Arkansas.[187] While analysis suggested that the increase is "almost certainly man-made", the USGS noted: "USGS’s studies suggest that the actual hydraulic fracturing process is only very rarely the direct cause of felt earthquakes." The increased earthquakes were said to be most likely caused by increased injection of gas-well wastewater into disposal wells.[188] The injection of waste water from oil and gas operations, including from hydraulic fracturing, into saltwater disposal wells may cause bigger low-magnitude tremors, being registered up to 3.3 (Mw).[189]
Induced seismicity from hydraulic fracturing
The United States Geological Survey (USGS) has reported earthquakes induced by hydraulic fracturing, and by disposal of hydraulic fracturing flowback into waste disposal wells, in several locations. Bill Ellsworth, a geoscientist with the U.S. Geological Survey, has said, however: “We don’t see any connection between fracking and earthquakes of any concern to society.” [190] The National Research Council (part of the National Academy of Sciences) has also observed that hydraulic fracturing, when used in shale gas recovery, does not pose a serious risk of causing earthquakes that can be felt.[191]A British Columbia Oil and Gas Commission investigation concluded that a series of 38 earthquakes (magnitudes ranging from 2.2 to 3.8 on the Richter scale) occurring in the Horn River Basin area between 2009 and 2011 were caused by fluid injection during hydraulic fracturing in proximity to pre-existing faults. The tremors were small enough that only one of them was reported felt by people; there were no reports of injury or property damage.[192]
A report in the UK concluded that hydraulic fracturing was the likely cause of two small tremors (magnitudes 2.3 and 1.4 on the Richter scale) that occurred during hydraulic fracturing of shale.[193][194][195]
Induced seismicity from water disposal wells
According to the USGS only a small fraction of roughly 40,000 waste fluid disposal wells for oil and gas operations in the United States have induced earthquakes that are large enough to be of concern to the public.[196] Although the magnitudes of these quakes has been small, the USGS says that there is no guarantee that larger quakes will not occur.[197] In addition, the frequency of the quakes has been increasing. In 2009, there were 50 earthquakes greater than magnitude 3.0 in the area spanning Alabama and Montana, and there were 87 quakes in 2010. In 2011 there were 134 earthquakes in the same area, a sixfold increase over 20th century levels.[198] There are also concerns that quakes may damage underground gas, oil, and water lines and wells that were not designed to withstand earthquakes.[197][199]Several earthquakes in 2011, including a 4.0 magnitude quake on New Year's Eve that hit Youngstown, Ohio, are likely linked to a disposal of hydraulic fracturing wastewater, according to seismologists at Columbia University.[200] A similar series of small earthquakes occurred in 2012 in Texas. Earthquakes are not common occurrences in either area. Disposal and injection wells are regulated under the Safe Drinking Water Act and UIC laws.[201]
Health impacts
Concern has been expressed over the possible long and short term health effects of air and water contamination and radiation exposure by gas production.[156][202][203] A study on the effect of gas drilling, including hydraulic fracturing, published by the Cornell University College of Veterinary Medicine, concluded that exposure to gas drilling operations was strongly implicated in serious health effects on humans and animals [204] although scientists have raised concerns about that particular report.[205] As of May 2012, the United States Institute of Medicine and United States National Research Council were preparing to review the potential human and environmental risks of hydraulic fracturing.[206][207]The U.S. Environmental Protection Agency considers radioactive material in flowback a hazard to workers at hydraulic fracturing sites. Workers may inhale radon gas released by the process, raising their risk of lung cancer. They are also exposed to alpha and gamma radiation released during the decay of radium-226 and to gamma radiation and beta particles released by the decay of radium-228, according to EPA. EPA reports that gamma radiation can also penetrate the skin and raise the risk of cancer.[208]
A 2012 study concluded that risk prevention efforts should be directed towards reducing air emission exposures for persons living and working near wells during well completions.[209] In the United States the Occupational Safety and Health Administration (OSHA) and the National Institute for Occupational Safety and Health (NIOSH) released a hazard alert based on data collected by NIOSH that workers may be exposed to dust with high levels of respirable crystalline silica (silicon dioxide) during hydraulic fracturing.[210] NIOSH notified company representatives of these findings and provided reports with recommendations to control exposure to crystalline silica and recommend 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.[211]
According to the United States Department of Energy, hydraulic fracturing fluid is composed of approximately 95% water, 4.5% sand and 0.5% different chemicals.[56] These percentages are by weight, so hydraulically fracturing a well uses 4-7 million gallons of water (15000-27000 tons) and 80-140 tons of chemicals. There can be up to 65 chemicals and often include benzyne, glycol-ethers, toluene, ethanol and nonphenols.[69][212] Some[who?] have argued that although many of these chemicals are harmful, some of them are either non toxic or are non toxic at lower dosages.[213] However, their concentration in hydraulic fracturing fluid have proven toxic to animals and humans.[204] Many chemicals used in fracking, such as 2-BE ethylene glycol, are carcinogenic. This chemical is listed under chronic oral RFD assessment, chronic inhalation RFC assessment, and carcinogenicity assessment records of the US environmental protection agency’s website.
In a study done by Colborn and colleagues, they examined 353 out of 994 fracking chemicals identified by TEDX in hydraulic fracking operation. They found over 75% of the 353 chemicals affected the skin, eyes, and other sensory organs,52% affected the nervous system, 40% affected the immune system and kidney system, and 46% affected the cardiocascular system and blood.[214]
In a second study done by Colborn and colleagues, they examined the airborne chemicals due to the fracking process. The group categorized the human tissue types into 12 categories and found 35 chemicals affected the brain/nervous system, 33 the liver/ metabolism, and 30 the endocrine system, which includes reproductive and developmental effects. The categories with the next highest numbers of effects were the immune system (28), cardiovascular/blood (27), and the sensory and respiratory systems (25 each). Eight chemicals had health effects in all 12 categories.[215]
Airborne chemicals during the fracking process, such as benzene and benzene derivatives, naphthalene, methylene chloride, are either carcinogenic or suspected as a human carcinogen to the human body.[215][216]
Published time: October 31, 2013 22:24
Pennsylvania authorities have denied a doctor the right to challenge a so-called “medical gag rule” that prevents him and other physicians from warning the public about the health dangers associated with fracking.
