Hydraulic fracturing
Encyclopedia
Considerable controversy surrounds the current implementation of hydraulic fracturing
technology in the United States. Hydraulic fracturing, or fracking, is the process of utilizing pressurized water, or some other liquid, to fracture rock layers and release petroleum
, natural gas
, or other substances so that they can be extracted. Environmental safety and health concerns about this process have emerged and are being debated at the state and national levels.
wells was first used in the United States in 1947. It was first used commercially by Halliburton
in 1949, and because of its success in increasing production from oil wells was quickly adopted, and is now used worldwide in tens of thousands of oil and natural gas wells annually. 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.
Volcanic dikes
and sills
are examples of natural hydraulic fractures. Hydraulic fracturing incorporates principles from the disciplines of fracture mechanics
, fluid mechanics
, solid mechanics
, and porous medium
flow.
& 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. The investigation was initiated after a 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."
In the United States, a 2004 Environmental Protection Agency
(EPA) study concluded that the process was safe and didn't warrant further study, because there was "no unequivocal evidence" of health risks, and the fluids were neither necessarily hazardous nor able to travel far underground. That study, however, was not intended as a general study of hydraulic fracturing, but only of its use in coalbed methane
deposits, and the study did not consider impacts above ground. The EPA report did find uncertainties in knowledge of how fracturing fluid migrates through rocks, and upon its release service companies voluntarily agreed to stop using diesel fuel as a component of fracturing fluid in coalbed methane walls due to public concerns of its potential as a source of benzene
contamination. 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.
The increased use of hydraulic fracturing has prompted more speculation about its environmental dangers. A 2008 investigation of benzene contamination in Colorado and Wyoming led some EPA officials to suggest hydraulic fracturing as a culprit. One of the authors of the 2004 EPA report states that it has been misconstrued by the gas-drilling industry.
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. 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 2011 peer-reviewed study found, on average, methane concentrations 17 times above normal in samples taken from water wells near shale gas drilling sites employing hydraulic fracturing. 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. 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. The research was conducted by scientists at Duke University and what they found was that "levels of flammable methane gas in drinking water wells increased to dangerous levels when those water supplies were close to natural gas wells. They also 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 manmade faults and fractures, or coming from cracks in the well structure itself ".
Methane contamination has been a common complaint among people who live near natural gas drilling areas. In 2009, a Propublica investigation revealed that methane contamination is widespread, "methane related to the natural gas industry has contaminated water wells in at least seven Pennsylvania counties since 2004". Because of this contamination, several homes have blown up after gas seeped into their water supplies; there have been reports of house explosions in Pennsylvania and Ohio. In one case in 2004, a methane leak caused an explosion that killed a couple and their 17 month old grandson.
A study published in May 2011 concluded that fracking has seriously contaminated shallow groundwater supplies in northeast Pennsylvania with flammable methane. However the study does not discuss how pervasive such contamination might be in other areas where drilling for shale gas has taken place.
per well. Some states, such as Texas
, Florida
, Arizona
, and California
are trying to get ahead of drinking water shortages by recycling sewage (also called effluent, gray, and reclaimed water
). This form of processing cannot, however, remove many of the toxins used in hydraulic fracturing or all pathogens present in wastewater. Its effectiveness and safety in converting wastewater into drinking water is being debated. This technology has been used in the US space program for years.
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 have been ordered to cease all operations in the state of Pennsylvania pending investigation. The Pennsylvania Department of Environmental Protection
has called this a "serious incident".
s 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; it is possible that 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 tremor
s 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 aquifer
s if the earthquake
s it induced continued.
study found that natural gas extracted by hydraulic fracturing may contribute as much to global warming
as coal, or more so. The authors of the study acknowledge, however, that the data they used were not the best available, so this has left the study open to interpretation. The natural gas industry has noted significant problems with the study's methodology, including comments from the authors that acknowledge the data may be unreliable.
In Garfield county, Colorado the Colorado School of Public Health released a second draft report released the Battlement Mesa Health Impact Assessment on March 1, 2011 for public comment.
University of Michigan-Ann Arbor in May 2011 began studying the effects of natural gas fracking on the Great Lakes.
Congress has requested that the EPA undertake a new, broader study of hydraulic fracturing. The report is due to be released in 2012.
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).
Furthermore, 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.
In May 2011, Jessica Ernst launched a multi million dollar lawsuit against Encana Corporation, the Alberta Energy Resources Conservation Board, and the Alberta government for contamination of her property and drinking water due to Encana’s fracking program. Encana fractures rock to extract coal bed methane, much as fracking is used to extract natural gas from shale. (In March, after a public hearing, Quebec put a moratorium on shale gas exploration pending a full environmental assessment of the potential damage from fracking.) According to the Statement of Claim, many Albertans depend on drinking water from coal bed aquifers, but Ms. Ernst’s water is now so contaminated that it can be lit on fire. She is also suing Alberta’s oil and gas regulator, alleging that it not only tolerated illegal behaviour by Encana and failed to protect her, but actively attempted to silence her complaints, and that Alberta Environment showed bad faith in “investigating” those complaints. The lawsuit, together with the Quebec moratorium, signals the likelihood of stronger environmental regulations of fracking in the pursuit of shale gas or coalbed methane.
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.
. 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 well
s, which would place them under federal regulation under the Safe Drinking Water Act. which was originally intended to regulate disposal wells.
In April 2011, the Ground Water Protection Council, in conjunction with the industry, began releasing well-by-well lists of hydraulic fracturing chemicals at http://www.FracFocus.org.
A complete listing of the specific chemical formulation of additives used in hydraulic fracturing operations is not currently made available to landowners, neighbors, local officials, or health care providers. This practice is under scrutiny as well.
Two studies released in 2009, one by the U.S. Department of Energy
and the other released by the Ground Water Protection Council, address hydraulic fracturing safety concerns. Chemicals which can be used in the fracturing fluid include kerosene
, benzene
, toluene
, xylene
, and formaldehyde
. These chemicals are not directly used as treating chemical additives but can be a small component of the specific chemicals used in the job.
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.
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.
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."
The New York State assembly voted 93 to 43, Nov. 30, 2010, to place a moratorium or freeze on hydraulic fracturing to give the state more time to undertake safety and environmental concerns.
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.
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:
Research should be completed by the end of 2012, and the EPA's Hydraulic Fracturing Report is expected to be completed in 2014.
The EPA Hydraulic Fracturing Draft Study Plan can be found here. Draft Plan
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 Congress adjourned (Jan. 3, 2011) without taking action on the FRAC Act. The 112th Congress has not re-introduced the bill or an equivalent.
, underground nuclear explosions were tested for natural gas stimulation. The Rulison
explosion multiplied the accessibility of the gas, but the gas was contaminated and unmarketable. Stimulation by nuclear explosion is not currently utilized by the industry.
News
Hydraulic fracturing
Considerable controversy surrounds the current implementation of hydraulic fracturing technology in the United States. Hydraulic fracturing, or fracking, is the process of utilizing pressurized water, or some other liquid, to fracture rock layers and release petroleum, natural gas, or other...
technology in the United States. Hydraulic fracturing, or fracking, is the process of utilizing pressurized water, or some other liquid, to fracture rock layers and release petroleum
Petroleum
Petroleum or crude oil is a naturally occurring, flammable liquid consisting of a complex mixture of hydrocarbons of various molecular weights and other liquid organic compounds, that are found in geologic formations beneath the Earth's surface. Petroleum is recovered mostly through oil drilling...
, natural gas
Natural gas
Natural gas is a naturally occurring gas mixture consisting primarily of methane, typically with 0–20% higher hydrocarbons . It is found associated with other hydrocarbon fuel, in coal beds, as methane clathrates, and is an important fuel source and a major feedstock for fertilizers.Most natural...
, or other substances so that they can be extracted. Environmental safety and health concerns about this process have emerged and are being debated at the state and national levels.
History
Hydraulic fracturing for stimulation of oil and natural gasNatural gas
Natural gas is a naturally occurring gas mixture consisting primarily of methane, typically with 0–20% higher hydrocarbons . It is found associated with other hydrocarbon fuel, in coal beds, as methane clathrates, and is an important fuel source and a major feedstock for fertilizers.Most natural...
wells was first used in the United States in 1947. It was first used commercially by Halliburton
Halliburton
Halliburton is the world's second largest oilfield services corporation with operations in more than 70 countries. It has hundreds of subsidiaries, affiliates, branches, brands and divisions worldwide and employs over 50,000 people....
in 1949, and because of its success in increasing production from oil wells was quickly adopted, and is now used worldwide in tens of thousands of oil and natural gas wells annually. 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
Quarry
A quarry is a type of open-pit mine from which rock or minerals are extracted. Quarries are generally used for extracting building materials, such as dimension stone, construction aggregate, riprap, sand, and gravel. They are often collocated with concrete and asphalt plants due to the requirement...
, near Mt Airy
Mount Airy, North Carolina
Mount Airy is a city in Surry County, North Carolina, United States. As of the 2010 census, the city population was 10,388.-History:Mount Airy was settled in the 1750s as a stagecoach stop on the road between Winston-Salem and Galax, Virginia. It was named for a nearby plantation...
, North Carolina
North Carolina
North Carolina is a state located in the southeastern United States. The state borders South Carolina and Georgia to the south, Tennessee to the west and Virginia to the north. North Carolina contains 100 counties. Its capital is Raleigh, and its largest city is Charlotte...
where it was (and still is) used to separate granite blocks from bedrock.
Volcanic dikes
Dike (geology)
A dike or dyke in geology is a type of sheet intrusion referring to any geologic body that cuts discordantly across* planar wall rock structures, such as bedding or foliation...
and sills
Sill (geology)
In geology, a sill is a tabular sheet intrusion that has intruded between older layers of sedimentary rock, beds of volcanic lava or tuff, or even along the direction of foliation in metamorphic rock. The term sill is synonymous with concordant intrusive sheet...
are examples of natural hydraulic fractures. Hydraulic fracturing incorporates principles from the disciplines of fracture mechanics
Fracture mechanics
Fracture mechanics is the field of mechanics concerned with the study of the propagation of cracks in materials. It uses methods of analytical solid mechanics to calculate the driving force on a crack and those of experimental solid mechanics to characterize the material's resistance to fracture.In...
, fluid mechanics
Fluid mechanics
Fluid mechanics is the study of fluids and the forces on them. Fluid mechanics can be divided into fluid statics, the study of fluids at rest; fluid kinematics, the study of fluids in motion; and fluid dynamics, the study of the effect of forces on fluid motion...
, solid mechanics
Solid mechanics
Solid mechanics is the branch of mechanics, physics, and mathematics that concerns the behavior of solid matter under external actions . It is part of a broader study known as continuum mechanics. One of the most common practical applications of solid mechanics is the Euler-Bernoulli beam equation...
, and porous medium
Porous medium
A porous medium is a material containing pores . The skeletal portion of the material is often called the "matrix" or "frame". The pores are typically filled with a fluid...
flow.
Contemporary use
Hydraulic fracturing is used in mining operations and to increase the production of oil and natural gas wells. It is also used in remediating subsurface contaminants.Water and health
In April 2010, the state of Pennsylvania banned Cabot OilCabot Oil
Cabot Oil & Gas Corporation is an independent petroleum and natural gas exploration and production company based in Houston, Texas ....
& 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. The investigation was initiated after a 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."
In the United States, a 2004 Environmental Protection Agency
United States Environmental Protection Agency
The U.S. Environmental Protection Agency is an agency of the federal government of the United States charged with protecting human health and the environment, by writing and enforcing regulations based on laws passed by Congress...
(EPA) study concluded that the process was safe and didn't warrant further study, because there was "no unequivocal evidence" of health risks, and the fluids were neither necessarily hazardous nor able to travel far underground. That study, however, was not intended as a general study of hydraulic fracturing, but only of its use in coalbed methane
Coalbed methane
Coalbed methane or Coal Bed Methane, coalbed gas or coal mine methane is a form of natural gas extracted from coal beds. In recent decades it has become an important source of energy in United States, Canada, and other countries...
deposits, and the study did not consider impacts above ground. The EPA report did find uncertainties in knowledge of how fracturing fluid migrates through rocks, and upon its release service companies voluntarily agreed to stop using diesel fuel as a component of fracturing fluid in coalbed methane walls due to public concerns of its potential as a source of benzene
Benzene
Benzene is an organic chemical compound. It is composed of 6 carbon atoms in a ring, with 1 hydrogen atom attached to each carbon atom, with the molecular formula C6H6....
contamination. Environmental group Riverkeeper
Riverkeeper
Riverkeeper is an environmental non-profit organization dedicated to the protection of the Hudson River and its tributaries, as well as the watersheds that provide New York City with its drinking water...
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.
The increased use of hydraulic fracturing has prompted more speculation about its environmental dangers. A 2008 investigation of benzene contamination in Colorado and Wyoming led some EPA officials to suggest hydraulic fracturing as a culprit. One of the authors of the 2004 EPA report states that it has been misconstrued by the gas-drilling industry.
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. 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
Allegheny River
The Allegheny River is a principal tributary of the Ohio River; it is located in the Eastern United States. The Allegheny River joins with the Monongahela River to form the Ohio River at the "Point" of Point State Park in Downtown Pittsburgh, Pennsylvania...
after treatment was 28 times accepted levels for drinking water.
A 2011 peer-reviewed study found, on average, methane concentrations 17 times above normal in samples taken from water wells near shale gas drilling sites employing hydraulic fracturing. 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. 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. The research was conducted by scientists at Duke University and what they found was that "levels of flammable methane gas in drinking water wells increased to dangerous levels when those water supplies were close to natural gas wells. They also 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 manmade faults and fractures, or coming from cracks in the well structure itself ".
Methane contamination has been a common complaint among people who live near natural gas drilling areas. In 2009, a Propublica investigation revealed that methane contamination is widespread, "methane related to the natural gas industry has contaminated water wells in at least seven Pennsylvania counties since 2004". Because of this contamination, several homes have blown up after gas seeped into their water supplies; there have been reports of house explosions in Pennsylvania and Ohio. In one case in 2004, a methane leak caused an explosion that killed a couple and their 17 month old grandson.
A study published in May 2011 concluded that fracking has seriously contaminated shallow groundwater supplies in northeast Pennsylvania with flammable methane. However the study does not discuss how pervasive such contamination might be in other areas where drilling for shale gas has taken place.
Impact on drinking water supplies
As also noted in the general article on Hydraulic Fracturing, there are also concerns about hydraulic fracturing's impact on drinking water supplies. The procedure uses millions of gallons of fresh waterFresh Water
Fresh Water is the debut album by Australian rock and blues singer Alison McCallum, released in 1972. Rare for an Australian artist at the time, it came in a gatefold sleeve...
per well. Some states, such as Texas
Texas
Texas is the second largest U.S. state by both area and population, and the largest state by area in the contiguous United States.The name, based on the Caddo word "Tejas" meaning "friends" or "allies", was applied by the Spanish to the Caddo themselves and to the region of their settlement in...
, Florida
Florida
Florida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...
, Arizona
Arizona
Arizona ; is a state located in the southwestern region of the United States. It is also part of the western United States and the mountain west. The capital and largest city is Phoenix...
, and California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
are trying to get ahead of drinking water shortages by recycling sewage (also called effluent, gray, and reclaimed water
Reclaimed water
Reclaimed water or recycled water, is former wastewater that is treated to remove solids and certain impurities, and used in sustainable landscaping irrigation or to recharge groundwater aquifers...
). This form of processing cannot, however, remove many of the toxins used in hydraulic fracturing or all pathogens present in wastewater. Its effectiveness and safety in converting wastewater into drinking water is being debated. This technology has been used in the US space program for years.
Well blowouts and spills of fracturing fluids
A well blowout in Clearfield County, Pennsylvania
Clearfield County, Pennsylvania
Clearfield County is a county located in the U.S. state of Pennsylvania. As of 2010, the population was 81,642.Clearfield County was created on March 26, 1804, from parts of Huntingdon and Lycoming Counties but was administered as part of Centre County until 1812...
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
EOG Resources
EOG Resources is a Fortune 500 company with its headquarters in the Heritage Plaza building in downtown Houston, Texas. The company is one of the largest independent oil and natural gas companies in the United States with proven reserves in the United States, Canada, Trinidad and Tobago, the United...
and the well completion company C.C. Forbes have been ordered to cease all operations in the state of Pennsylvania pending investigation. The Pennsylvania Department of Environmental Protection
Pennsylvania Department of Environmental Protection
The Pennsylvania Department of Environmental Protection was established on July 1, 1995, is the agency in the U.S. State of Pennsylvania responsible for protecting and preserving the land, air, water, and energy resources through enforcement of the State's environmental laws...
has called this a "serious incident".
Natural gas drilling and seismic events
Injection of fluid into subsurface geological structures, such as faultFault
Fault may refer to:*Fault , planar rock fractures which show evidence of relative movement*Fault , in dog breeding, is an undesirable aspect of structure or appearance that indicates the dog should not be bred...
s and fractures, reduces the effective normal stress acting across these structures. If sufficient shear stress
Shear stress
A shear stress, denoted \tau\, , is defined as the component of stress coplanar with a material cross section. Shear stress arises from the force vector component parallel to the cross section...
is present, the structure may slip in shear and generate seismic events over a range of magnitudes; it is possible that 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
Subsidence
Subsidence is the motion of a surface as it shifts downward relative to a datum such as sea-level. The opposite of subsidence is uplift, which results in an increase in elevation...
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 tremor
Tremor
A tremor is an involuntary, somewhat rhythmic, muscle contraction and relaxation involving to-and-fro movements of one or more body parts. It is the most common of all involuntary movements and can affect the hands, arms, eyes, face, head, vocal folds, trunk, and legs. Most tremors occur in the...
s of no greater than 2.8 on the Richter scale
Richter magnitude scale
The expression Richter magnitude scale refers to a number of ways to assign a single number to quantify the energy contained in an earthquake....
were reported on June 2, 2009 in Cleburne, Texas
Cleburne, Texas
Cleburne is a city in Johnson County, Texas, United States, and a suburb of Fort Worth. According to 2007 United States Census Bureau estimates, the population is 29,050. It is the county seat of Johnson County. Cleburne is named for a Confederate General, Patrick Cleburne...
, the first in the town's 140-year history.
Fracking connected to deep well waste water disposal has been banned in Arkansas
Arkansas
Arkansas is a state located in the southern region of the United States. Its name is an Algonquian name of the Quapaw Indians. Arkansas shares borders with six states , and its eastern border is largely defined by the Mississippi River...
due to the risk of contaminating aquifer
Aquifer
An aquifer is a wet underground layer of water-bearing permeable rock or unconsolidated materials from which groundwater can be usefully extracted using a water well. The study of water flow in aquifers and the characterization of aquifers is called hydrogeology...
s if the earthquake
Earthquake
An earthquake is the result of a sudden release of energy in the Earth's crust that creates seismic waves. The seismicity, seismism or seismic activity of an area refers to the frequency, type and size of earthquakes experienced over a period of time...
s it induced continued.
Air and health
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. Many particulates and chemicals can be released into the atmosphere, such as sulfuric oxide, nitrous oxides, volatile organic compounds (VOC), benzene, toluene, diesel fuel, hydrogen sulfide which can have serious health implications.Other consequences
A 2011 Cornell UniversityCornell University
Cornell University is an Ivy League university located in Ithaca, New York, United States. It is a private land-grant university, receiving annual funding from the State of New York for certain educational missions...
study found that natural gas extracted by hydraulic fracturing may contribute as much to global warming
Global warming
Global warming refers to the rising average temperature of Earth's atmosphere and oceans and its projected continuation. In the last 100 years, Earth's average surface temperature increased by about with about two thirds of the increase occurring over just the last three decades...
as coal, or more so. The authors of the study acknowledge, however, that the data they used were not the best available, so this has left the study open to interpretation. The natural gas industry has noted significant problems with the study's methodology, including comments from the authors that acknowledge the data may be unreliable.
In Garfield county, Colorado the Colorado School of Public Health released a second draft report released the Battlement Mesa Health Impact Assessment on March 1, 2011 for public comment.
University of Michigan-Ann Arbor in May 2011 began studying the effects of natural gas fracking on the Great Lakes.
Congress has requested that the EPA undertake a new, broader study of hydraulic fracturing. The report is due to be released in 2012.
Occupational hazards
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).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).
Economic impacts
The economic impacts of hydraulic fracturing include property owners that receive funds, 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.Furthermore, 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.
Lawsuits
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 May 2011, Jessica Ernst launched a multi million dollar lawsuit against Encana Corporation, the Alberta Energy Resources Conservation Board, and the Alberta government for contamination of her property and drinking water due to Encana’s fracking program. Encana fractures rock to extract coal bed methane, much as fracking is used to extract natural gas from shale. (In March, after a public hearing, Quebec put a moratorium on shale gas exploration pending a full environmental assessment of the potential damage from fracking.) According to the Statement of Claim, many Albertans depend on drinking water from coal bed aquifers, but Ms. Ernst’s water is now so contaminated that it can be lit on fire. She is also suing Alberta’s oil and gas regulator, alleging that it not only tolerated illegal behaviour by Encana and failed to protect her, but actively attempted to silence her complaints, and that Alberta Environment showed bad faith in “investigating” those complaints. The lawsuit, together with the Quebec moratorium, signals the likelihood of stronger environmental regulations of fracking in the pursuit of shale gas or coalbed methane.
In June 2011, Northeast Natural Energy sued the town of Morgantown, West Virginia
Morgantown, West Virginia
Morgantown is a city in Monongalia County, West Virginia. It is the county seat of Monongalia County. Placed along the banks of the Monongahela River, Morgantown is the largest city in North-Central West Virginia, and the base of the Morgantown metropolitan area...
, 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.
Regulation
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 ActSafe Drinking Water Act
The Safe Drinking Water Act is the principle federal law in the United States intended to ensure safe drinking water for the public. Pursuant to the act, the Environmental Protection Agency is required to set standards for drinking water quality and oversee all states, localities, and water...
. 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
Energy Policy Act of 2005
The Energy Policy Act of 2005 is a bill passed by the United States Congress on July 29, 2005, and signed into law by President George W. Bush on August 8, 2005, at Sandia National Laboratories in Albuquerque, New Mexico...
exempted fractured wells from being re-classified as injection well
Injection well
An injection well is a vertical pipe in the ground into which water, other liquids, or gases are pumped or allowed to flow.-Waste disposal: One application is waste water disposal, in which treated waste water is injected into the ground between impermeable layers of rocks to avoid polluting fresh...
s, which would place them under federal regulation under the Safe Drinking Water Act. which was originally intended to regulate disposal wells.
In April 2011, the Ground Water Protection Council, in conjunction with the industry, began releasing well-by-well lists of hydraulic fracturing chemicals at http://www.FracFocus.org.
A complete listing of the specific chemical formulation of additives used in hydraulic fracturing operations is not currently made available to landowners, neighbors, local officials, or health care providers. This practice is under scrutiny as well.
Two studies released in 2009, one by the U.S. Department of Energy
United States Department of Energy
The United States Department of Energy is a Cabinet-level department of the United States government concerned with the United States' policies regarding energy and safety in handling nuclear material...
and the other released by the Ground Water Protection Council, address hydraulic fracturing safety concerns. Chemicals which can be used in the fracturing fluid include kerosene
Kerosene
Kerosene, sometimes spelled kerosine in scientific and industrial usage, also known as paraffin or paraffin oil in the United Kingdom, Hong Kong, Ireland and South Africa, is a combustible hydrocarbon liquid. The name is derived from Greek keros...
, benzene
Benzene
Benzene is an organic chemical compound. It is composed of 6 carbon atoms in a ring, with 1 hydrogen atom attached to each carbon atom, with the molecular formula C6H6....
, toluene
Toluene
Toluene, formerly known as toluol, is a clear, water-insoluble liquid with the typical smell of paint thinners. It is a mono-substituted benzene derivative, i.e., one in which a single hydrogen atom from the benzene molecule has been replaced by a univalent group, in this case CH3.It is an aromatic...
, xylene
Xylene
Xylene encompasses three isomers of dimethylbenzene. The isomers are distinguished by the designations ortho- , meta- , and para- , which specify to which carbon atoms the two methyl groups are attached...
, and formaldehyde
Formaldehyde
Formaldehyde is an organic compound with the formula CH2O. It is the simplest aldehyde, hence its systematic name methanal.Formaldehyde is a colorless gas with a characteristic pungent odor. It is an important precursor to many other chemical compounds, especially for polymers...
. These chemicals are not directly used as treating chemical additives but can be a small component of the specific chemicals used in the job.
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.
Congress has been urged to repeal the 2005 regulatory exemption under the Energy Policy Act of 2005. The FRAC Act
Fracturing Responsibility and Awareness of Chemicals Act
The Fracturing Responsibility and Awareness of Chemicals Act , - dubbed the FRAC Act - was introduced to both houses of the 111th United States Congress on June 9, 2009, and aims to repeal the exemption for hydraulic fracturing in the Safe Drinking Water 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.
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."
The New York State assembly voted 93 to 43, Nov. 30, 2010, to place a moratorium or freeze on hydraulic fracturing to give the state more time to undertake safety and environmental concerns.
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.
EPA Hydraulic Fracturing Study
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 ShaleBakken FormationThe Bakken formation, initially described by geologist J.W. Nordquist in 1953,is a rock unit from the Late Devonian to Early Mississippian age occupying about of the subsurface of the Williston Basin, underlying parts of Montana, North Dakota, and Saskatchewan...
- Kildeer, and Dunn Counties, North Dakota - Barnett ShaleBarnett ShaleThe Barnett Shale is a geological formation located in the Bend Arch-Fort Worth Basin. It consists of sedimentary rocks of Mississippian age in Texas...
- Wise and Denton Counties, Texas - Marcellus ShaleMarcellus FormationThe Marcellus Formation is a unit of marine sedimentary rock found in eastern North America...
- Bradford and Susquehanna Counties, Pennsylvania - Marcellus ShaleMarcellus FormationThe Marcellus Formation is a unit of marine sedimentary rock found in eastern North America...
- Washington County, Pennsylvania - Raton BasinRaton BasinThe Raton Basin is a geologic structural basin in southern Colorado and northern New Mexico. It takes its name from Raton Pass and the town of Raton, New Mexico. In extent, the basin is approximately east-west, and north-south, in Huerfano and Las Animas Counties, Colorado, and Colfax County,...
- Las Animas 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.
The EPA Hydraulic Fracturing Draft Study Plan can be found here. Draft Plan
Fracturing Responsibility and Awareness of Chemicals Act
In June 2009 two identical bills named the Fracturing Responsibility and Awareness of Chemicals ActFracturing Responsibility and Awareness of Chemicals Act
The Fracturing Responsibility and Awareness of Chemicals Act , - dubbed the FRAC Act - was introduced to both houses of the 111th United States Congress on June 9, 2009, and aims to repeal the exemption for hydraulic fracturing in the Safe Drinking Water Act...
were introduced to both the United States House and the Senate. The House bill was introduced by representatives Diana DeGette
Diana DeGette
Diana Louise DeGette is the U.S. Representative for , serving since 1997, and a Chief Deputy Whip. She is a member of the Democratic Party.The district is based in Denver.-Early life, education and career:...
, D-Colo., Maurice Hinchey
Maurice Hinchey
Maurice Dunlea Hinchey , is the U.S. Representative for , serving since 1993. He is a member of the Democratic Party...
D-N.Y., and Jared Polis
Jared Polis
Jared Schutz Polis is an American entrepreneur, philanthropist, and U.S. Representative for , serving since 2009. He is a member of the Democratic Party...
, D-Colo. The Senate version was introduced by senators Bob Casey
Bob Casey, Jr.
Robert Patrick "Bob" Casey, Jr. is the senior U.S. Senator from Pennsylvania and a member of the Democratic Party. He previously served as Pennsylvania Treasurer, and Pennsylvania Auditor General. He is the son of former Governor Bob Casey, Sr..He is the first Democrat elected to a full term in...
, 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 Congress adjourned (Jan. 3, 2011) without taking action on the FRAC Act. The 112th Congress has not re-introduced the bill or an equivalent.
Halliburton's hydraulic fracturing operations
As mandated by EPA subpoena, Halliburton has released information about hydraulic fracturing operations. Details regarding Halliburton’s fracturing process and fracturing chemicals can be found on their website.Fracturing method: high pressure by combustible gas mixtures or driving forces
Fracturing is done by pumping in liquids at high pressure. In the past, combustible gas mixtures, driving liquids or explosives generated high-pressure high-speed gas flow (TNT or PETN up to 1,900,000 psi). In the late 1960s and early 1970s, as part of Operation PlowshareOperation Plowshare
Project Plowshare was the overall United States term for the development of techniques to use nuclear explosives for peaceful construction purposes...
, underground nuclear explosions were tested for natural gas stimulation. The Rulison
Rulison
Project Rulison, named after the rural community of Rulison, Colorado, was a 40-kiloton nuclear test project in the United States on September 10, 1969, about 8 miles SE of the town of Grand Valley, Colorado near western Colorado's Grand Valley in Garfield County. The location of "Surface Ground...
explosion multiplied the accessibility of the gas, but the gas was contaminated and unmarketable. Stimulation by nuclear explosion is not currently utilized by the industry.
See also
- Energy in the United States
- GaslandGaslandGasland is a 2010 American documentary film written and directed by Josh Fox. The film focuses on communities in the United States impacted by natural gas drilling and, specifically, a stimulation method known as hydraulic fracturing.-Synopsis:...
- a 2010 documentary by Josh Fox exploring environmental impact of hydraulic fracturing in the United States
External links
- U.S. EPA — EPA and hydraulic fracturing page
- FrackTrack - Pennsylvania Marcellus Shale Mapping Application
- Natural Gas Drilling In Marcellus Shale - NYC Dept. Of Environmental Protection
- SavetheWaterTable.org — ORG dedicated to saving the aquifer in the face of fracking
- EPA Opens Public Hearings on Health and Environmental Impact of Hydraulic Fracturing — video report by Democracy Now!Democracy Now!Democracy Now! and its staff have received several journalism awards, including the Gracie Award from American Women in Radio & Television; the George Polk Award for its 1998 radio documentary Drilling and Killing: Chevron and Nigeria's Oil Dictatorship, on the Chevron Corporation and the deaths of...
- Treatment of Fracture Stimulated Wells Publication discussing the process of testing and treating fracture stimulated wells.
- Shale Shock Upstate New York organization dedicated to education, outreach, and organizing resistance against drilling in the Marcellus Shale.
- www.globalresearch.ca
News
- Pressconnects.com Marcellus Shale — Newspaper website covering Hydraulic fracturing & Marcellus Shale
- Energy: The Pros and Cons of Shale Gas Drilling a 60 Minutes60 Minutes60 Minutes is an American television news magazine, which has run on CBS since 1968. The program was created by producer Don Hewitt who set it apart by using a unique style of reporter-centered investigation....
report on fracing by Chesapeake EnergyChesapeake EnergyChesapeake Energy is the second largest producer of natural gas in the United States, a top 15 producer of U.S. liquids and the most active driller of new wells, according to an November 2011 investor presentation. It recorded 3Q 2011 natural gas production of an average of approximately of...
originally broadcast on November 14, 2010