In the face of dwindling natural gas supplies and an energy crunch, the U.S. Department of Energy began conducting the "Eastern Gas Shales Project" in the 1970s. It had two goals: evaluate the gas potential of Devonian and Mississippian shale basins and develop new drilling, stimulation, and recovery technologies. It was determined that there were large supplies of gas in the shale rock, but no technology to extract it. A coordinated private-public R&D effort was launched to create a "technological fix."
According to Slate, the US DOE subsidized George P. Mitchell's Mitchell Energy "to drill its first horizontal wells, covering any costs beyond a typical vertical well, and the federal government provided unconventional gas tax credits. The Bureau of Economic Geology created high-resolution images of rock surfaces that yielded information about their porosity. Union Pacific Resources, the Fort Worth-based exploration and production company, shared its superior method for hydraulic fracturing. DOE´s Sandia Labs contributed microseismic fracture mapping software that helped the operator make adjustments to improve the flow of gas. Mitchell put it all together, and by the time he sold his company to Devon Energy in 2002, the idea of extracting natural gas from shale was about to turn from technological pipe dream to very real economic powerhouse."
Slate continues: "The shale gas R&D projects assumed a kind of vacuum. The only criteria were technical feasibility and economic profitability, and the innovators failed to consider questions about how the technologies would play out in the real world. What is the long-term fate of the chemicals that remain underground? What do we do with the toxic mixture of fracking fluids and naturally occurring radioactive materials that flows back up the wellbore during drilling and production? What are the air quality and climate implications? Can we safely frack in places where people live? What happens when the wells run dry? Is it wise to further commit ourselves to a finite fossil resource that requires such extreme measures to extract?"
What Fracking Involves
Hydraulic fracturing involves two main types of fluid streams, slickwater and crosslinked gel. Both are water based, and it is most typical that freshwater is used as the base. Slickwater contains freshwater to which a friction reducing agent is added. The purpose of this is to decrease the amount of pipe friction as the fluid is pumped. This decreases the required surface pressure needed to perform the job. The lack of other additives to slickwater is thought to also help keep the fracturing fluid from damaging especially "tight" or impermeable formations. The crosslink gel system is typically fresh water to which has been added guar (a common food additive). The purpose of the guar in this case is to increase the viscosity of the fluid in order to allow it to carry more proppant, and to keep the proppant from settling as it enters the formation. Additional chemical additives may include hydrochloric acid (typically pumped before the job to clean up the formation), additional friction reducers, clay control, weighting agents, and gel breakers. There are additional additives not mentioned here, and each individual job is tailored to the specific formation. Additives are becoming available at www.fracfocus.org as a way to inform the general public about fracturing in their area. However additives considered trade secrets are not available.
Estimating Fracture Growth
Prior to pumping fracture stimulations are typically modeled based on both job and formation parameters. Following the drilling of a wellbore typically loggin suites are run in order to determine information about the formation. Typically a logging run is made using a wireline with a logging tool suspended at the end of the cable. The tool is lowered into the wellbore and is used to measure the formation properties. Some properties are directly measured and some are calculated based on other measurements. Parameters may include: bulk density, porosity, permeability, fluid saturation and type, as well as formation type. Logging tools are much more sophisticated than their representation here. This data is put into a fracture stimulation program such as GOPHER or FracPro and a "typical" job is designed before the model is run. Typically this job is designed by both engineers from the production company as well as engineers from the service company. The model estimates the fracture geometry, and that design is iterated until a final design is chosen. 
Marcellus Shale Hydraulic Fracturing
The Marcellus shale is a large shale formation in the eastern United States spanning parts of New York and Pennsylvania. Until recently this shale has been uneconomic to produce due to the tight impermeable nature of the reservoir rock. Recently due to advances in both horizontal drilling and hydraulic fracturing it has become economic to develop fields in this area in order to produce the gas lying in the formation. For a typical well in the Marcellus, first a horizontal wellbore is drilled into the zone of interest. The wellbore starts vertically before making a turn into the zone of interest in order to maximize the wellbore exposure to the productive interval. After drilling is completed the well is typically stimulated with multistage fractures. In a multistage fracture a single treatment is pumped targeting a section of the wellbore. Once that zone has been treated another section of the wellbore is selected and treated. This makes fracture stimulating the Marcellus shale more water and proppant intensive than other parts of the United States.
As of 2012, fracking is exempt from seven major federal regulations:
As of February 2012, only four of 31 fracking states have significant drilling rules. Five states have adopted disclosure rules, although they still allow for "proprietary trade secrets."
Hydrofracking and the "Halliburton Loophole"
In 2005, at the urging of Vice President *** Cheney, Congress created the so-called "Halliburton loophole" to clean water protections in federal law to prevent the U.S. Environmental Protection Agency from regulating this process, despite serious concerns that were raised about the chemicals used in the process and its demonstrated spoiling and contamination of drinking water. In 2001, Cheney's "energy task force" had touted the benefits of hydrofracking, while redacting references to human health hazards associated with hydrofracking. Halliburton, which was previously led by Cheney, reportedly earns $1.5 billion a year from its energy operations, which rely substantially on its hydrofracking business.
According to Pro Publica reporter Abrahm Lustgarten, the EPA under Christine Todd Whitman's tenure as Administrator engaged in secret negotiations with industry, while purportedly addressing drinking water issues related to "fracking." In 2004, the EPA undertook a study on the issue and "the EPA, despite its scientific judgment that there was a potential risk to groundwater supplies, which their report clearly says, then went ahead and very surprisingly concluded that there was no risk to groundwater," Lustgarten noted in September 2009. "[P]art of my reporting found that throughout that process the EPA was closer than seemed comfortable with the industry. I filed FOIA requests for some documents and found conversations between Halliburton employees and the EPA researchers, essentially asking for an agreement from Halliburton in exchange for more lax enforcement. The EPA, in these documents, appeared to offer that and agree to that. And it doesn’t appear, by any means, to have been either a thorough or a very objective study." 
In June 2009, U.S. Representatives Diana DeGette, John Salazar and Maurice Hinchey and Senators Robert P. Casey Jr. and Chuck Schumer introduced the Fracking Responsibility and Awareness of Chemicals Act (FRAC ACT). The proposal is aimed at closing the 'Halliburton loophole' and requiring the oil and gas industry to disclose the chemicals used in drilling projects which can contaminate ground water and drinking water.
In late October 2009 the House of Representatives agreed to include a statement in the Interior and Environment Appropriations bill and report for fiscal year 2010 urging the EPA to reassess the impact of fracking on water supplies. The report stated:
- "The conferees urge the EPA to carry out a study on the relationship between hydraulic fracturing and drinking water, using a credible approach that relies on the best available science, as well as independent sources of information. The conferees expect the study to be conducted through a transparent, peer-reviewed process that will ensure the validity and accuracy of the data. EPA shall consult with other federal agencies as well as appropriate state and interstate regulatory agencies in carrying out the study, and it should be prepared in accordance with EPA quality assurance principles."
On March 18, 2010, the Environmental Protection Agency announced that it would lead a $1.9 million for this comprehensive, peer-reviewed study on the impacts hydrofracking would have on water quality and public health. Despite the study, Rep. Diana DeGette (D-CO) has expressed that it is crucial to continue the push forward for the passing of the FRAC Act
More information about other legislative proposals can be found in the main page on this topic, Marcellus Shale.
Possible violations of the Safe Drinking Water Act
Although the 2005 Bush-Cheney Energy Policy Act exempted hydraulic fracturing from the Safe Drinking Water Act - the "Halliburton Loophole" - it made one small exception: diesel fuel. The Policy Act states that the term “underground injection,” as it relates to the Safe Drinking Water Act, “excludes the underground injection of fluids or propping agents (other than diesel) pursuant to hydraulic fracturing operations related to oil, gas, or geothermal production activities [italics added].” But a congressional investigation has found that oil and gas service companies used tens of millions of gallons of diesel fuel in fracking operations between 2005 and 2009, thus violating the Safe Drinking Water Act. Diesel fuel contains a number of toxic constituents including benzene, toluene, ethylbenzene, and xylene, which have been linked to cancer and other health problems.
In a letter to EPA Administrator Lisa Jackson, the congressional committee noted that between 2005 and 2009, “oil and gas service companies injected 32.2 million gallons of diesel fuel or hydraulic fracturing fluids containing diesel fuel in wells in 19 states.” None of the companies sought or received permits to do so. “This appears to be a violation of the Safe Drinking Water Act. It also means that the companies injecting diesel fuel have not performed the environmental reviews required by the law.” Yet because the necessary environmental reviews were circumvented, the companies were unable to provide data on whether they had used diesel in fracking operations in or near underground sources of drinking water.
The EPA is conducting its own study of the impact of hydraulic fracturing on drinking water supplies, due out in late 2012. It is unknown whether companies that have violated the Safe Drinking Water Act since 2005 be held accountable. Matt Armstrong, a lawyer with the Washington firm Bracewell & Giuliani, which represents several oil and gas companies, told the New York Times: “Everyone understands that E.P.A. is at least interested in regulating fracking.” But: “Whether the E.P.A. has the chutzpah to try to impose retroactive liability for use of diesel in fracking, well, everyone is in a wait-and-see mode. I suspect it will have a significant fight on its hands if it tried it do that.”
Air quality impacts
According to the study conducted by professor Robert W. Howarth of Cornell University, "3.6% to 7.9% of the methane from shale-gas production escapes to the atmosphere in venting and leaks over the lifetime of a well." According to the study, this is at least 30% and perhaps even 100% more than from conventional gas production. The study explains these higher emissions with hydraulic fracturing and drill out following the fracturing. In 2008, measured ambient concentrations near drilling sites in Sublette County, Wyoming were frequently above the National Ambient Air Quality Standards (NAAQS) of 75ppb and have been recorded as high as 125 ppb. A 2011 study for the city of Fort Worth, Texas, examining air quality around natural gas sites "did not reveal any significant health threats." In DISH, Texas, elevated levels of disulphides, benzene, xylenes and naphthalene have been detected in the air. People living near shale gas drilling sites often "complain of headaches, diarrhea, nosebleeds, dizziness, blackouts, muscle spasms, and other problems." Cause-and-effect relationships have not been established. In Garfield County, Colorado, another area with a high concentration of drilling rigs, volatile organic compound emissions increased 30% between 2004 and 2006; during the same period there was a rash of health complaints from local residents. Epidemiological studies that might confirm or rule out any connection between these complaints and fracking are virtually non-existent.In 2012, researchers from the Colorado School of Public Health showed that air pollution caused by fracking may contribute to "acute and chronic health problems" for those living near drilling sites.
In May 2012 it was reported that the shale energy boom around the world was fuelling a rise in the burning of waste gas after years of decline. Global gas flaring crept up by 4.5 percent in 2011. The increase is mostly due to the rise in shale oil exploration in North Dakota, propelling the United States into the top 10 gas flaring countries along with Russia, Nigeria and Iraq.
Water quality Impacts
Although no complete list of the cocktail of chemicals used in this process exists, information obtained from environmental clean-up sites demonstrates that known toxins are routinely being used, including hydrochloric acid, diesel fuel (which contains benzene, tuolene, and xylene) as well as formaldehyde, polyacrylimides, arsenic, and chromates. In a letter to Congress, an Environmental Protection Agency employee describes how the Bush Administration's EPA produced a scientifically unsupportable conclusion that hydrofracking should not be regulated under the Clean Water Drinking Act. These chemicals include known carcinogens and other hazardous substances.
On May 4, 2012 the Obama administration announced proposed rules that will require companies to disclose the chemicals used during their fracking process, but do so after, not before, they finish operations. The regulations would only account for the natural gas and oil deposits located on BLM land, which is considered a "sliver" of total lands where fracking occurs. “These proposed rules from the Department of the Interior fall far short of what’s needed to protect public health,” said Jessica Ennis, legislative representative for Earthjustice. The EPA announced they will permit diesel fuel oil and gas hydraulic fracturing.
Fracking and the New York City Water Supply
Citizen groups have mobilized in New York to oppose hydrofracking. This opposition has deployed several tactics, including a class action lawsuit. New videos have also been produced to educate the public about the dangers of fracking the Marcellus shale. In the following video, Manhattan Borough President Scott Stringer calls massive proposed drilling operations in the watershed that provides New York City with its drinking water is the "most alarming environmental news he has heard in a long time, and makes this the number one environmental crisis" they face in the city:
In response to these and other concerns, New York City urged the state to ban methane gas drilling in its watershed on Wednesday, December, 23, 2009. Steven Lawitts, the city's top environmental official, called fracking techniques "unacceptable threats to the unfiltered fresh water supply of nine million New Yorkers," putting the City at odds with the methane gas industry, which considers shale drilling completely safe. Marc LaVorgna, spokesman for NYC Mayor Michael Bloomberg stated, "Based on all the facts, the risks are too great and drilling simply cannot be permitted in the watershed."
The New York Times noted that the New York State Department of Environmental Conservation, which was tasked with "going through a public review of its new rules on hydraulic fracturing," was looking into reports that "gas companies use at least 260 types of chemicals, many of them toxic, like benzene. These chemicals tend to remain in the ground once the fracturing has been completed, raising fears about long-term contamination."
American Rivers, a Washington, D.C. advocacy group, announced on June 3, 2010, that hydrofracking poses a huge threat to the Delaware River, which is the drinking source for nearly 17 million people across New York, New Jersey, and Pennsylvania. In the America's Most Endangered Rivers Report: 2010 Edition report, the American Rivers advocacy group named the Delaware River the number one most at-risk river, due to the threat of extensive drilling into the Marcellus Shale.
Here a Factsheet produced by the American Rivers Group on the potential threat faced to the Delaware River by drilling into the Marcellus Shale: http://www.americanrivers.org/assets/pdfs/mer-2010/upperdelaware_factsheet_2010.pdf.
Possible Cases of Water Contamination on a State by State Basis
On November 9, 2009, Reuters reported that the owner of 480 acres of land in southwest Pennsylvania claimed Atlas Energy Inc. ruined his land with toxic chemicals used in or released there by hydraulic fracturing, and he also claimed to find seven potentially carcinogenic chemicals above permissible levels set by the U.S. Environmental Protection Agency. He performed tests on his well water a year before drilling began and said the water conditions were "perfect." After the drilling began, water tests found arsenic at 2,600 times acceptable levels, benzene at 44 times above limits and naphthalene five times the federal standard. He has decided to sue Atlas Energy Inc. for negligence and is seeking an injunction against further drilling, and unspecified financial damages. Jay Hammond, general counsel for Atlas, said Zimmermann's claims are "completely erroneous" and said Atlas will "vigorously" defend itself in court and declined further comment.
Later that month on November 20, 2009, Reuters reported that residents of Dimock sued Cabot Oil & Gas Corp claiming the company's natural-gas drilling had contaminated their water wells with toxic chemicals, caused sickness and reduced their property values. The complaint says residents have suffered neurological, gastrointestinal and dermatological symptoms from exposure to tainted water. They also say they have had blood test results consistent with exposure to heavy metals. The lawsuit accuses Cabot of negligence and says it has failed to restore residential water supplies disrupted by gas drilling. Contaminated water from methane gas drilling operations, such as in Dimock, Pennsylvania, is often ten times more toxic than water produced from petroleum production, and can contain high concentrations of salts, acids, benzene, toluene, ethylbenzene, xylene, radioactive materials," and other chemicals. 
Oil and gas drilling in Colorado, predominantly in western Colorado, has raised health concerns from residents who believe the industry is the root cause of their illnesses or that is has exacerbated disease.
Chris Mobaldi, who lived in Rifle, Colorado, believes her neurological system was damaged by drinking water that may have been contaminated by drilling fluids from wells around her home. She had two tumors removed from her pituitary gland and endured excruciating pain. 
Odor complaints and air pollution concerns are also on the rise in Garfield County, on the western slope, where longtime residents often endure hazy skies in the Colorado River valley. Many believe the gas industry is responsible. Carol and Orlyn Bell noticed a "terrible" smell when they neared their Dry Hollow ranch, south of Silt, Colorado. "It was the strongest odor we've smelled in the last four years," Carol Bell said. The Bells said the odor came from nearby gas wells and production facilities, something they've seen surround their 110-acre ranch within the span of four years.  From September to December, 2005, the Colorado Oil and Gas Commission documented ten complaints from eight separate households related to odors emanating from wells being drilled and completed by the Barrett Corporation 
A study conducted over three years by the Colorado School of Public Health concluded that fracking can contribute to “acute and chronic health problems for those living near natural gas drilling sites”. "The study found those living within a half-mile of a natural gas drilling site faced greater health risks than those who live farther away." Researchers located “potentially toxic petroleum hydrocarbons in the air near the wells including benzene, ethylbenzene, toluene and xylene.” Benzene is classified as a known carcinogen by the EPA. he study reiterates earlier research which shows that prolonged exposure to airborne petroleum hydrocarbons causes “an increased risk of eye irritation and headaches, asthma symptoms, acute childhood leukemia, acute myelogenous leukemia, and multiple myeloma.”
For more information on this study see: Colorado and fracking.
In the April 30, 2009 Pro Publica's Abrahm Lustgarten wrote about a story he dug up from Louisiana's Shreveport Times. The story revealed that 16 cattle mysteriously and abruptly dropped dead in a "northwestern Louisiana field after apparently drinking from a mysterious fluid adjacent to a natural gas drilling rig, according to Louisiana's Department of Environmental Quality. At least one worker told the newspaper that the fluids . . . were used for . . . hydraulic fracturing.
In late 2007, three families near Grandview, Texas noticed changes in their well water just after a natural gas well within a couple of hundred yards of their properties was hydraulically fractured. Within days, five goats and a llama had died. All three families noticed strong sulfur smells in their water, making it unusable. At first their water ran dry, and then the water returned with extremely high pressure, blowing out pipes. Showering caused skin irritation. The Railroad Commission of Texas acknowledged that testing of well water found toluene and other toxic contaminants.
Reuters reported that "the U.S. Environmental Protection Agency found 14 "contaminants of concern" in 11 private wells in the central Wyoming farming community of Pavillion, an area with about 250 gas wells.
In its 2011 report of the same study, the EPA said it identified numerous fracking chemicals in Pavillion's water: benzene was found at 50 times safe levels, along with other hazardous chemicals, methane, diesel fuel, and heavy metals - in both groundwater and deep wells.
In a study released in May 2012 an independent scientist confirmed that fracking contaminated a drinking water source east of the town of Pavillion, Wyoming, supporting the findings in a draft EPA report published in December 2011.
It was reported by the Associated Press in May 2012 that Wyoming's governor persuaded the head of the EPA to postpone an announcement linking fracking to groundwater contamination, giving state officials — whom the EPA had privately briefed on the study — time to attempt to debunk the finding in the Pavillion, Wyoming area.
In response to public concerns about hydraulic fracturing the oil and gas industry has set up www.fracfocus.org to inform residents near their wells of the chemicals used in the fracturing process. Again this website does not contain fluids perceived to be trade secrets. The industry also relies on scientific study in order to try to alleviate public concern. It is the position of the oil and gas industry that some of the fracturing fluids and chemicals do indeed stay in the reservoir. However, because the reservoir is typically thousands of feet below aquifers, those aquifers are required to be protected by casing and cement, and the "impermeable nature of the rock above the reservoir chances of aquifer contamination are miniscule at best." All hydrocarbon reservoirs require an impermeable seal to keep the lighter hydrocarbons from migrating to the surface. Were this seal not intact, the reservoir would long ago have been depleted." Finally, the industry argues that recent papers relying on microseismic data from 11,000 cases in the Marcellus shale failed to detect a microseismic event within 2000 feet of the deepest water wells in each county, indicating that fracture height growth is not capable of reaching existing aquifers; the paper is SPE 145949 Hydraulic Fracture Height Growth: Real Data. Halliburton has recently released a new fracture stimulation fluid system sourced solely from the Generally Recommended as Safe (GRAS) list published by the FDA in an attempt to alleviate public concerns. 
Documentary Film Gasland Explores the Harms Caused by Hydrofracking
Gasland is a 2010 documentary about unconventional natural gas drilling, or hydraulic fracturing. Its director, Josh Fox, lives in the Upper Delaware River Basin, on the border between Pennsylvania and New York State, part of the area of Marcellus Shale. (For more information on Gasland, Marcellus Shale, and the impact of drilling on drinking water, please see SourceWatch's water clearinghouse.)
In May 2008, Fox received a letter from a natural gas mining company, who wanted to lease 19.5 acres of land from Fox for $100,000. On an interview on NPR's Fresh Air, Fox said the company stated,"'We might not even drill. We don't even know if there's gas here. It's going to be a fire hydrant in the middle of a field — very little impact to your land. You won't hardly know we're here.' " Instead of saying yes, Fox decided to travel around the country to see how the process of natural gas drilling affected other communities and homeowners, producing the documentary Gasland.
Some homeowners he spoke to noticed that their water had been discolored, or was starting to bubble. In some communities, people were able to light the water coming out of their faucets on fire — because chemicals from the natural gas drilling process had seeped into the water, an event documented in the film. Despite the pollutants, Fox says, "[t]he gas industry is very powerful, and their power in Congress is well shown. They were exempted from the Safe Drinking Water Act by the 2005 Energy bill. The Safe Drinking Water Act monitors underground injection of toxins. They were also exempted in previous years from the Clean Air Act, the Superfund Law. . . . It's an unregulated industry."
Energy in Depth, a Washington, D.C. based oil and gas industry group, has created a web page with a list of claimed factual inaccuracies in the documentary. In response to the EID's list of claimed factual inaccuracies, the Gasland website offers a full point-by-point rebuttal.
In a blog-post for Forbes magazine, Dr. Michael Economides, an oil and gas industry analyst and Chairman of the Board of XGAS, a natural gas firm, commented on the Gasland scene of "a man lighting his faucet water on fire and making the ridiculous claim that natural gas drilling is responsible for the incident. The clip, though attention-getting, is wildly inaccurate and irresponsible. To begin with, the vertical depth separation between drinking water aquifers and reservoir targets for gas production is several thousand feet of impermeable rock. Any interchange between the two, if it were possible, would have happened already in geologic time, measured in tens of millions of years, not in recent history." Economides claims that almost any "gas leak" from sources within and around a home has the potential to produce flammable tap water.
It was announced in May 2012 that Institute of Medicine stated that they will examine whether the process of hydraulic fracturing poses potential health challenges. 
Expected EPA Study Release
A comprehensive study by the EPA is expected to be released in 2012. While this will in no way be the definitive report on hydraulic fracturing, it is expected that a lot of future policy will be based on the study's findings.
Lobbying and political donations
The Environment News Service reported that, from 1990 - 2011, oil and gas companies contributed $238.7 million into gubernatorial and Congressional election campaigns to persuade lawmakers that fracking is safe. The fracking industry spending especially targeted oversight - members of the House Energy and Commerce Committee and the Senate Committee on Environment and Public Works.
Republican candidates received at least three times more cash than Democratic candidates. Top Congressional recipients include:
The industry spent an additional $726 million on lobbying from 2001.
Fracking on federal lands
According to a 2012 report released by the House Natural Resources Committee’s Democratic, the Interior Department collected less than $300,000 in fines over a thirteen year period from oil and gas companies that had violated regulations for hydraulic fracturing on federal lands. The committee staff report said enforcement was "erratic and inconsistent," and highlighted the need for agency reform.
The report was a review of violations, fines, and regulations related to oil and gas activities on public lands in 17 states. It found that from 1998 to 2011, there were a total of 2,025 safety and drilling violations that were issued to 335 companies in seventeen states between February 1998 and February 2011, 549 of which were classified as “major." In dozens of cases, oil and gas companies started to drill on federal lands before their permit was fully approved. The report found that the total amount of fines issued for all violations to more than 300 companies in 17 states was $273,875 -- a tiny percentage of industry profits.
To view resources and actual article (this was cut/paste) follow here: http://www.sourcewatch.org/index.php?title=Fracking