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Hydraulic Fracturing

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

Map of shale formations in the United States

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

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

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




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

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

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

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

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

Fracturing Fluid Composition

Table 1: Additives and Chemicals Found in Hydraulic Fracturing Fluid: Purposes and Potential Effects 1,4

Additive Category

Purpose of Additive

Chemical Examples


Toxicological Information


To create pathways in limestone formations for gas to travel through. To clean perforations of mud and cement before fluid injection.

Hydrochloric Acid (3% to 28%)
Acetic Acid
Formic Acid

  • Poisonous
  • Highly corrosive
  • Can cause severe eye, skin, and respiratory burns and tissue damage


To kill or inhibit growth of bacteria and microorganisms that could produce gas and contaminate methane. Bacteria can also break down gelling agents and reduce viscosity of fracturing fluid.

Polycyclic organic matter
Polynuclear aromatic hydrocarbons

  • Skin and eye irritant
  • Harmful if swallowed
  • Irritant


To reduce viscosity of fluid to allow proppant into fractures, which enhances flowback.

Diammonium peroxidisulphate
Ammonium persulfate
Ammonium sulphate
Ethylene glycol
Glycol ethers

  • Skin, eye and respiratory irritant
  • Harmful if swallowed
  • Irritant

Clay Stablizer/Control

To stabilize clay in well.

Tetramethyl ammonium chloride
Potassium Chloride

  • Skin, eye and respiratory irritant
  • Harmful if swallowed
  • Irritant

Corrosion Inhibitor

Prevents acid from corroding and reduces rust formation in well casing, tubing, and tools.

Propargyl alcohol

  • Flammable
  • Harmful if inhaled or swallowed
  • Can cause blindness and be fatal if swallowed.
  • Can cause central nervous system depression.
  • Can cause respiratory and digestive tract irritation.
  • Can cause heart, liver, and kidney damage.


Increases fluid viscosity allowing more proppant to be transported into fractures more easily.

Boric Acid
Ethylene glycol

  • Harmful if swallowed
  • Combustible
  • Eye, skin, and respiratory irritant.
  • Can cause liver, cadiovascuar, brain, central nervous system, kidney, damage.
  • Can cause birth defects
  • Irritant.

Friction Reducer

To reduce friction between the well casing and the fracking fluid.

Sodium acrylate-acylamide copolymer

  • Skin, eye, and respiratory tract irritant.
  • Irritant

Geling Agent
(for linear gels)

Increases fluid viscosity allowing more proppant to be transported into fractures more easily.

Guar Gum

  • Mild irritant
  • No known toxicological properties.

Iron Control

Prevents metal oxides from precipitating out of the earth so that they don't block the tubing.

Citric acid
Thioglycolic Acid

  • Severe eye irritant.
  • Skin and respiratory tract irritant.
  • Irritant.

Linear Gel Delivery System

Used in linear gels in place of water because of its higher carrying capacity for guar gum powder.


  • Harmful if swallowed
  • Combustible
  • Skin and respiratory tract irritant.
  • Known carcinogens
  • Irritant
  • Can cause skin disorders


Holds fractures open to allow the gas or fluid to flow more easily through the fractures.

Ceramic Beads

  • None
  • None

Scale Inhibitor

Prevents precipitation of carbonates and sulfates into the well.

Ammonium chloride
Ethylene glycol

  • Mild eye and skin irritant.
  • Irritant


Reduces the fracturing fluid's surface tension which increases fluid recovery.


  • Flammable
  • Harmful if inhaled or swallowed
  • Can cause blindness and be fatal if swallowed.
  • Can cause central nervous system depression.
  • Can cause respiratory and digestive tract irritation.
  • Can cause heart, liver, and kidney damage.


Environmental and Human Health Impacts


In September 2010 Riverkeeper, New York’s clean water advocate, compiled cases from around the country where gas drilling and hydraulic fracturing activities were confirmed or suspected to be the cause of environmental and human health impacts. The impacts in Riverkeeper’s report, Fractured Communities: Case studies of the environmental impacts of gas drilling, included well blowouts and explosions, drinking and surface water contamination, improper wastewater discharge, stray gas migration, and air pollution. The exact cause of some of the impacts were unknown or still being investigated but a large number of the events that lead to environmental damage were caused by improper drilling procedures, mistakes made by the drilling crew,  or improper and/or overpressurized well casings. The drilling companies and crews also frequently violate oil and gas laws by not maintaining proper drilling logs, submitting well records, illegally discharging waste and/or fracturing fluid, or complying with government consent orders, such as supplying potable drinking water to residents who’s water has been affected by gas drilling operations.  For example, as of August 2010 the Pennsylvania Department of Environmental Protection (PA DEP) records showed that there had been 1,435 violations of Pennsylvania state oil and gas laws, 669 traffic citations, and 818 written warnings issued to trucks hauling wastewater over a two and a half year period.[5] Specific cases of gas drilling activities resulting in environmental damage, from Riverkeeper’s report along with other sources, are examined below.

Well Blowouts, Explosions and Stray Gas Migration

On June 3, 2010 there was a well blowout in Clearfield County, Pennsylvania that resulted in, what investigators believe to be, approximately 1 million gallons of wastewater and natural gas erupting into the air for 16 hours.[6]  The well was owned by EOG Resources (formerly Enron Oil and Gas) and the blowout was caused by improper well equipment and untrained personnel who did not know the proper well control protocol. One investigator found that EOG failed to have an adequate number of pressure barriers between the producing shale formation and the atmospheres.[7] EOG personnel had also failed to properly test the Blow-Out-Preventers and there were no personnel on site at the time of the blowout that had proper Well Control Certification credentials.[8] After the incident, two nearby streams were polluted and 35,000 gallons of polluted water was collected, which is not believed to be the full amount of wastewater released from the well. The drilling fluids also discharged into a tributary of Little Laurel Run, which is a high quality cold water fishery. In total the well blowout amounted to five violations of the Pennsylvania Oil & Gas Act, five violations of the Clean Streams Law, two violations of the state’s Air Act and four violations of the Solid Waste Management Act. EOG Resources and C.C. Forbes LLC (EOG’s contractor) were fined $400,000 and ordered to take corrective actions.[9]

A few days later another explosion occurred on June 7, 2010 at a Chief Oil & Gas and AB Resources Gas well in Marshall County, West Virginia. The drilling crew had just started the hydraulic fracturing process when they hit a pocket of methane causing an explosion that sent seven injured crew members to the hospital.[10] An initial investigation by the West Virginia Department of Environmental Protection (WV DEP) indicated that the drilling operator failed to follow the drilling plan outlined by the permit. WV DEP ordered AB Resources to cease all drilling and they were issued two notices of violations for improper casing of the gas well. AB Resources was cited for inaccurately reporting the coal seam depth when applying for the drilling permit and for failing to set well casing at the permitted depth. The company was then ordered to review all the coal seam depths and well casing depths for all drilled and proposed wells, as well as follow West Virginia Code that requires a crew member trained in blowout prevention to be present at all times during drilling operations. WV DEP lifted the cease order on July 21, 2010, allowing drilling operation to recommence.[11]

On December 15, 2007 gas drilling operations in Bainbridge, OH caused an explosion inside a residential home.[12] Luckily the two residents were not injured but the structure of the house was significantly damaged. The Ohio Department of Natural Resources (Ohio DNR) determined that the explosion was caused by hydraulic fracturing activities being performed by Ohio Valley Energy Systems Corp. (OVESC) in the Clinton sandstone formation.[13] OVESC had begun drilling in the area just two months before the explosion, and a further investigation determined that the explosion had been caused by the “accumulation and confinement of deep, high-pressure gas in the surface production casing annulus (the space between the piping and the well bore)…which resulted in over-pressurization of the annulus”[14] The over-pressurization caused gas to migrate out of the well through the natural fractures in the bedrock to local aquifers, water wells and structures in the area. Ohio DNR sampled 78 local wells and found that 45 had measurable levels of dissolved methane. Many of the wells also had iron and manganese present and levels of total dissolved solids that exceeded U.S. EPA Secondary Maximum Contaminant Levels.[15] Ohio DNR determined the gas migration and explosion were caused by “(i) inadequate cementing of the production casing; (ii) the decision to proceed with hydrofracturing the well without addressing the inadequate cementing of the casing; and (iii) most significantly, the 31-day period after the fracturing during which the annular space between the surface and the production casing was ‘mostly shut in’”[16]. The deep, high pressure gas was confined in a restricted space without proper casing, which caused it to migrate into the bedrock and up towards the surface where water supplies were contaminated and dangerous amounts of methane were released.

Over pressurization of the annulus and improper well casing has led to numerous cases of gas migration, many of which have put the environment and human safety at risk as well as causing dangerous explosions in residential areas. In March 2004 a home exploded in Jefferson County, PA due to pressurization of the annulus of at least one nearby operating well. The explosion caused three fatalities.[17] In July 2009, a natural gas leak was confirmed in Lycoming County, PA by the PA DEP to be coming from an East Resources well being drilled nearby that was believed to have improper well casing. The leaking methane impacted numerous private drinking wells in the area, two tributaries of Lycoming Creek, and even forced one resident to evacuate.[18] In Armstrong County, PA, in October 2007, pressurization of an annulus of a newly drilled gas well caused gas to migrate and cause an explosion at a water well enclosure that damaged the pump, enclosure and water quality of the well.[19] A gas migration incident in Millcreek, PA, in November 2007, caused residents to evacuate their homes when the PA DEP found that the natural gas levels in and around their homes were at explosive levels.[20] Isotopic analysis of the gas confirmed that recently drilled gas wells nearby were the cause of the migration, which forced five families to evacuate their homes for 39 days.[21] These examples are just a few of the known incidents of gas migration caused by high-pressure hydraulic fracturing activities across the country.

The majority of the cases of stay gas migration are caused by improper drilling techniques, such as improper casing or cementing of casing, or letting the well and annulus get over pressurized so that the gas is forced into natural fractures and up to the surface. If caught early enough the effects of gas migration can be somewhat remedied by placing additional casing and relieving pressure from the well, however many cases could have also been prevented if proper drilling techniques and protocols were followed when the gas wells are initially drilled.

Drinking water contamination, surface spills, and illegal discharges

One of the largest concerns that many people have with hydraulic fracturing and the issue that gets the most media attention is water contamination. Ground and surface water contamination is a common complaint among residents that live near natural gas drilling sites. Stay gas migration, as explored above, has been one of major culprits contributing to water contamination, but methane is not the only chemical of concern. Hydraulic fracturing fluids contain hundreds of chemicals that contribute to make the fracking process as efficient as possible, and improper use and control of these fluids can result in further contamination issues that have been seen all across the country.

In April 2009, Schreiner Oil and Gas, which had recently drilled 26 wells in McKean County, PA, was found responsible for contaminating seven drinking water supplies. The PA DEP found that two of the drinking wells had excess levels of methane and five were found to have iron and manganese levels that were above federal and state drinking standards.[22] This incident caused the PA DEP to issue Schreiner its fourth notice of violation for failing to submit well records for a number of their wells. They had been issued violations in the past for over pressurized wells, failing to post their well permits, and wastewater pit violations.[23] A follow-up investigation a year later indicated that two homes were still experiencing contamination issues. Their drinking water was found to contain chlorides, manganese, iron, and dissolved methane and ethane gas. Schreiner was ordered by the PA DEP to improve the cement casing at their well sites to reduce the amount of water contamination.[24]

In the City of Midland, TX a home owner’s well was found to have 50 times the acceptable level of hexavalent chromium.[25] This discovery led the Texas Commission on Environmental Quality (TCEQ) to investigate 240 wells in the area. 42 wells were found to have dangerous levels of hexavalent chromium and were provided with filters to help reduce the contamination.[26] The TCEQ believes that the contamination is likely due to gas drilling operations in the region, but Schlumberger gas, the regional operator, denies any connection to the contamination issues.[27]

After hydraulic fracturing started in Dish, TX, locals started to notice their tap water change to an unappealing grey color. Further analysis revealed that the water contained elevated levels of arsenic, lead, chromium, butanone, acetone, carbon disulfide and strontium, some of which were at concentrations up to 21 times the legal limit.[28]

In 2010 the Louisiana Department of Environmental Quality (LA DEQ) found Chesapeake Energy and Schlumberger technology responsible for the deaths of 17 cattle.[29] A milky substance, that was later found to have elevated levels of potassium chloride, had flowed from the well site into the pasture, where the cows had access to it. Nearby residents said the cows had died a slow and painful death, making loud cries and bleeding and foaming from the mouth. Each of the two responsible companies was fined $22,000 for the incident.[30]

The LA DEQ was forced to issue an evacuation in Caddo Parish in late 2010, when Exco Resources unexpectedly hit a shallow pocket of gas and natural gas began leaking into the air and making its way into nearby aquifers. Gas was found at explosive levels in some local water wells, and though the evacuation wasn’t mandatory, those that stayed were unable to use or drink their water supplies.

In Pavillion, WY the EPA found that groundwater supplies were highly contaminated with chemicals known to be used in the hydraulic fracturing process, including benzene, methane, and other petroleum compounds. [31] The U.S. Department of Health and Human Services’ Agency for Toxic Substances and Disease Registry (ATSDR) recommended that residents find alternative sources for drinking and cooking water, and that they ventilate rooms while showering, to prevent health side effects and lower the risk of explosion.[32]

Colorado has experienced a large natural gas boom over the past decade and along with it came hundreds of violations and incidents that caused environmental damage. From 2008-2009 the Colorado Oil and Gas Conservation Commission (COGCC) examined violations by 17 different gas companies, which totaled more than $602,000 in damage. The violations included more than 700 different incidents of waste water being spilled or illegally released into the environment. 182 spills were found to contaminate ground water, 82 had contaminated surface waters, and 10 spills had managed to contaminate both surface and ground waters.[33] In 2008 430 spills had be reported and the COGCC had issued 208 notices of alleged violations (NOAVs), and in 2009 371 spills had been reported and 260 NOAVs were issued.[34] As a result of these spills at least 26 residential water wells and 11 natural springs were contaminated. [35]

In 2008 in Garfield County, CO a correlation was found between the increasing amount of dissolved methane and chloride in the groundwater and the increasing number of natural gas wells being drilled in the area.[36] BTEX (benzene, toluene, ethylbenzene and total xylenes) was found by COGCC to be contaminating the local water supplies.[37] EnCana, which had already been found responsible and fined for water contamination in 2005, was ordered by the COGCC to fix the contamination issue.[38]

In December 2009 an Atlas Resources wastewater pit overflew and hydraulic fracturing fluids were released into a high-quality watershed in Hopewell Township, PA. Atlas did not report the incident to the PA DEP, despite the fact that the spill violated the Oil and Gas Act, the Clean Streams Las, and the Solid Waste Management Act, and cleaned the spill up themselves. When the PA DEP learned of the incident in August 2010 Atlas was fined $97,350. The regional PA DEP director commented on the incident saying that it was “unacceptable for drilling companies in Pennsylvania to threaten public safety or harm the environment through careless acts, such as this…Companies must adopt operating standards that prevent these sorts of accidents and they must make protecting our water resources a top priority.”[39] Further investigation into Atlas Resources led the PA DEP to discover that they had violated state environmental laws at at least 13 well sites. They have failed to implement proper erosion and sediment control measures, they have discharged diesel fuel and fracturing fluid into the ground, and they have failed to restore well sites on multiple occasions. Despite these violations, Atlas Resources still hold 250 permits for well sites on the Marcellus shale. [40]

Accidents caused by improperly trained personnel, improper drilling techniques, and poor waste management are often the cause of major environmental impacts. Also in Hopewell Township, PA, a broken transmission line caused 250 barrels (7875 gallons) of hydraulic fracturing fluid to spill into a warmwater fishery. At least 168 fish and other aquatic life were found dead. [41] In Bradford County, PA pump failure and a large collection of sand in a valve at a Talisman Energy well caused 4,200 gallons of fracking flowback fluid to spill into a cold-water fishery. [42] In January 2008, a tear in the lining of a Marathon Oil storage pit caused 1.4 million gallons of hydraulic fracturing fluid to spill into Parachute Creek, CO.[43]  Williams Production Co., the largest natural gas producer in Western Colorado, reported at least 74 spills occurring between 2007 and 2010, and have been issued 28 NOAVs from COGCC. Operations at one of their well pads, which was not properly installed or maintained and was operating without a permit, caused wastewater contamination of a nearby spring. However, Williams disputed the claims and paid $423,000 to settle the state investigation.[44]

Illegal and/or accidental discharges of fracturing fluids have also contributed to environmental contamination. Fortuna Energy illegally discharged fracturing flowback fluids through a vegetated area and into Sugar Creek, but was only fined $3,500 by the PA DEP. [45] Tapo Energy, in June 2010, accidently spilled an unknown quantity of “petroleum-based material” which ended up contaminating a three mile long segment of Buckeye Creek in West Virginia. [46]

One of the major issues faced by natural gas drilling companies is what to do with the hundreds of thousands to millions of gallons of wastewater that is produced from each well drilled.  Some of fluid is recycled, and most of it remains in the ground, but a large portion of wastewater needs to be disposed of or treated so that the water can be recycled and reused. In October of 2008 the PA DEP noticed that the levels of total dissolved solids (TDS) were exceeding federal and state water quality standards in the Monongahela River. [47] An investigation by the Army Core of Engineers indicated that the TDS levels were five times larger than average, and twice the legal limit.[48] The PA DEP ordered the sewage treatment plants to lower the amount of gas drilling wastewater they accept from the current 20% to 1% of their daily flow, in attempts to reduce the levels of TDS in the river. The Army Core of Engineers, who had written to the EPA about the issue, increased the flow rate from dams on the Monongahela River in attempts to ameliorate the problem.[49] Their attempts had limited success and in October 2009, a year later, the levels of TDS in the river still exceed acceptable standards. [50]

Air impacts

Many areas around natural gas drilling sites, especially those in Texas, have also experienced a rise in air pollution due to drilling activities. In August 2009, in the Town of Dish, TX a local government study found that the air in residential areas contained high concentrations of carcinogenic and neurotoxic compounds, including benzene, xylene, carbon disulfide, naphthalene, dimethyl disulfide, and others. [51] The TCEQ initially said that the levels in the air exceeded both short term and long term acceptable levels. However, they soon issued a memorandum saying that the air didn’t exceed short term limits but the concentration levels of benzene could cause long-term health risk to local residents if the concentrations don’t decline.[52] The Dallas-Fort Worth Area, which is located by the Barnett shale, has experienced a drastic increase in air pollution since gas drilling operations increased in the area. A regional EPA administrator reported that each day pollutant emissions from natural gas drilling operations in the area surpassed those produced by all of the vehicle traffic in Dallas-Fort Worth region. [53] A TCEQ study also concluded that benzene levels in the air exceeded short term limits in some locations in the Dallas-Fort Worth area.


The Dimock Dilemma


The residents of Dimock, a small town in Pennsylvania, have received a lot of media attention in recent years because of the large number of residents that have been affected in the area by hydraulic fracturing activities. The large amount of media attention has caused Dimock to become a center for the fight against hydraulic fracturing, and activists, including The Avengers new Hulk, Mark Ruffalo, have gathered in Dimock to speak out against gas drilling and the environmental damage being caused by drilling activities.

Cabot Oil & Gas started drilling in Dimock, PA in 2006, and since, many residents have suffered water contamination from methane and other chemicals known to be involved in the fracking process.  The issue of water contamination in Dimock started to draw more attention after a local resident’s water well exploded on January 1, 2009.[54] Drillers had been drilling and fracking just a few hundred yards away from her home. State investigators believe that the high pressurized fluids being pumped into the earth during the fracturing process pushed methane through fractures in the ground and into her well which was then sparked by a motorized pump within her well.[55] The explosion caused a several thousand pound piece of concrete to be blasted up into the air.[56] Following the explosion there were a number of other reports of methane migrating to the surface and into drinking water supplies. Investigations done by the PA DEP found that nine wells were contaminated with methane, four of which posed a threat of explosion.[57] Isotopic analysis of the gas within these wells by the PA DEP concluded that the methane originated from the formation that Cabot Oil & Gas was targeting with drilling operations, and disproved the claim made by Cabot that the methane was naturally occurring biogenic methane or shallower coal bed methane.[58] In February 2009 the PA DEP issued a violation to Cabot for discharging natural gas, which is considered a polluting substance, to local waters of the Commonwealth without authorization, and for failing to prevent the gas from entering groundwater supplies.[59] Further investigation by the PA DEP found that a number of their gas wells were cemented improperly or insufficiently which had allowed natural gas to migrate into groundwater sources.[60] Fifteen Dimock families filed federal lawsuits in 2009 against Cabot Oil & Gas which, at that point in time, had acquired 130 drilling violations at their Dimock wells.[61]

In addition to the methane migration Cabot was also responsible for two liquid gel spills in September 2009. A total of 8,000 gallons of lubricant gel, used for hydraulic fracturing, was released during the two spills which polluted the nearby Steven’s Creek, causing many fish to die in the wetland area.[62] Cabot stated that the two spills were caused by failed pipe connections.[63] The PA DEP charged Cabot with unpermitted discharge of polluting substances, an unpermitted discharge of residual waste, two unpermitted encroachments on Stevens Creek, not containing polluting substances at the well site, and an unpermitted discharge of industrial waste. These are all violations of either the Pennsylvania Clean Streams Law, Pennsylvania Solid Waste Management Act, the Dam Safety and Encroachments Act, and/or the Oil and Gas Act.[64] The stream was flushed with water to remove the gel. Less than a week after the two spills an additional spill occurred at the same well site when a hose ruptured because a closed valve caused a buildup of pressure within the hose. The rupture caused another spill of 420 gallons of the same lubricant gel.[65]

The PA DEP continued to investigate the problems in Dimock for eleven months, until November 2009 when a consent order and agreement was created between Cabot Oil & Gas and the DEP. The results of the investigation had found numerous violations including: improper or insufficient well casings, discharge or natural gas into groundwater, contamination of private water supplies, gas migration, illegal discharge of drilling fluids, and failing to submit drilling records and keep drilling logs.[66] More specific details of the violations that Cabot was cited for in the November 2009 agreement are as follows: two Cabot wells were found to have excessive pressures and three had insufficient or improper casing which can allow gas to escape or build up between casings;[67] even though aware of the issue, Cabot had still failed to solve the casing issues in those three wells at the time of the consent agreement.[68]

After sampling wells that provide water for thirteen Dimock homes, the DEP found elevated levels of dissolved methane in all of the wells, and detected combustible gas in the headspaces of seven of those wells.[69] The investigation also determined that ten of the affected water supplies are less than 1000 feet from one or more Cabot gas wells, and that the presence of dissolved methane and/or combustible gas in those groundwater supplies occurred within six months of drilling completion of one or more of the nearby gas wells.[70] This unpermitted discharge of natural gas into groundwater supplies is in violation of the Clean Streams Act. According to the Oil & Gas Act Cabot is therefore determined responsible for the stray gas migration and the pollution of the affected water supplies.[71] The other three affected groundwater supplies are within 1300 feet of one or more Cabot gas wells, and due to similar pollution and location as the other ten affected water supplies Cabot was also deemed responsible for those three supplies.[72]

Cabot had also failed, at the time of the agreement, to restore or replace the water supplies they had polluted, which is in violation of the Oil & Gas Law and the Pennsylvania Code.[73] Cabot has also been cited with numerous violations of the Clean Streams Act and the Solid Waste Management Act at a number of their wells due to illegal discharging of drilling mud, which is considered industrial and/or residual waste.[74] In January 2009 they violated the Solid Waste Management Act when a leak in a fuel line for a drilling pump caused 100 gallons of diesel fuel to spill at one of Cabot’s well sites.[75] Cabot has also been cited a number of times for not keeping or submitting well records on time and for not keeping proper drilling logs for inspection during the drilling process, both of which violate the Oil & Gas Act.[76] All of the above violations were taken into account when the PA DEP and Cabot drafted the initial Consent Order and Agreement on November 4, 2009.

The Consent Order and Agreement enforced strict regulations on Cabot if they were going to continue drilling and ordered Cabot to comply with all environmental laws and regulations, including the Clean Streams Act, the Oil and Gas Act, and the Solid Waste Management Act, as well as take corrective actions to solve the issues they have caused in Dimock.[77] Cabot was also ordered to stop all drilling until they had written authorization from the PA DEP. Some of the corrective actions Cabot was ordered to complete were as follows: submit casing and cementing plans to the DEP for a new well 10 business days before beginning drilling, submit plans on how they are going to test the integrity of well casing and cementing, and plug the wells that were identified to be causing gas migration because of insufficient or improper casing.[78] Cabot was also ordered to supply potable drinking water to the affected residents and/or supply gas mitigation devices to the affected water supplies until such a time that the DEP decides that the affected water supplies have been restored to a usable state.[79] Cabot was also ordered to pay a $120,000 civil penalty for the violations outlined by the consent order and was subject to future fines if the consent order was violated.[80] 

Within the next year the consent order was revised twice after Cabot failed to comply with all of the obligations laid down by the original agreement.[81] In April 2010 the PA DEP suspended all permit applications and fined Cabot $240,000.[82] Cabot was also ordered to pay an additional $30,000 a month until they complied with all obligations set by the original consent order. DEP secretary John Hanger stated that “Cabot had every opportunity to correct these violations, but failed to do so. Instead, it chose to ignore its responsibility to safeguard the citizens of this community and to protect the natural resources there. I have ordered that all of Cabot’s permit applications for further drilling in any region of the state be put on-hold, indefinitely, until the region’s homeowners receive their new water treatment systems, the fines are paid, and the wells are plugged.” He continued to state that “gas migration is a serious issue that can have dire consequences to affected communities and we will not allow Pennsylvania’s citizens to be put in harms way by companies that chose not to follow the law.”[83] When Cabot continually failed to comply with the consent order it was revised again in December 2010. The PA DEP ordered Cabot to pay the impacted families twice their property values, totaling, according to Hanger, over $4 million and provide the families with gas mitigation devices that would filter the methane out of their water.[84] Cabot made it very clear that they did not agree with the DEP’s findings but agreed to the terms of the new agreement. [85]

In October 2011 Cabot claimed that they had met all the terms of the agreement and requested to stop supplying water to the affected families. The DEP, bound by the law and the consent order, agreed to let Cabot stop water deliveries to the affected Dimock households, though they still were required to provide gas mitigation devices.[86] Some residents, however, refuse the gas mitigation devices because they claim that though they remove the gas they don’t remove the other harmful chemicals that are now present in their water supplies because of hydraulic fracturing activities.[87] The stoppage of the water deliveries caused uproar in the community, which then caused the town to receive more attention from both the media and the EPA. The EPA got involved and agreed to provide four households with potable water and test 60 households in the area for methane and other chemicals.[88] A further investigation done by the EPA in early 2012 found that a number of wells had potentially dangerous chemicals present in concentrations higher than the established trigger levels, which are determined by “risk based screening levels and/or standards for public water supplies”.[89] The chemicals found above the determined trigger level included:  fluoride, arsenic, chromium, sodium, barium, lead, lithium, and manganese.[90] The EPA also found elevated levels of methane and total coliform bacteria, bacteria related to E. Coli.[91] On July 25, 2012 the EPA announced that it had completed its testing in Dimock and that it too would stop its water deliveries because the agency determined that the hazardous levels of chemicals such as arsenic and barium could be reduced to safe levels using treatments systems.[92]

In August 2013, environmentalists from Pennsylvania made the trek down to Washington, DC with more than 50,000 petitions calling the EPA to reopen their investigation in Dimock.[93] Regional EPA officials are in agreement with locals and were opposed to the decision to close the investigations of the gas drilling companies in the area. Despite finding dangerous levels of methane, barium, arsenic, sodium and manganese in the water supplies of multiple houses and wells in Dimock, the EPA had claimed last July that the water in Dimock was safe to drink because treatment would reduce the level of toxins in the water.[94] Contrary to these conclusions by the EPA, locals claim the problem is getting worse. Local residents hope to inspire federal officials to reopen the investigation, but Cabot Oil and Gas has already expressed their discouragement. Still trying to make the ignorant claim that natural gas drilling has had no effect on the region, spokesman George Stark from Cabot stated that “Methane is a pre-existing condition, in the 1800s it was there.”[95] Craig Stevens would disagree. Having watched and tasted his water go from clean and drinkable before the drilling companies showed up to a discolored, metallic tasting substance that gave him nose bleeds after the fracking had commenced, he claims that this is a civil and humans rights issue.[96] Stevens has challenged the federal and state officials to come drink a “32-ouncer” of his well water and still try to make the claim that it is safe, but so far no one has followed up on that challenge.[97]




2 Hydraulic Fracturing: History of An Enduring Technology by Carl T. Montgomery and Michael B. Smith, NSI Technologies. and Hydraulic Fracturing: The Fuss, The Facts, The Future. by Robin Beckwith, JPT/JPT Online. JPT December 2010.

[5] Pennsylvania Land Trust Association, Marcellus Shale Drillers in Pennsylvania Amass 1614 Violations since 2008 (September 1, 2010), available at:

[6] See PA DEP Consent Order and Agreement with EOG Resources (July 12, 2010), available at:; see also PA DEP Consent Order and Agreement with CC Forbes (July 12, 2010) , available at:;  PA DEP, Punxsutawney Hunting Club 36H Well Report (July 12, 2010), available at: ; PA DEP, Independent Report Faults Clearfield County Gas Well Operators for

June 3 Blowout DEP Outlines Proper Procedures for all Marcellus Drilling Firms (July 13, 2010), available at:

[7] Vittitow, John G., Sr., Bedrock Engineering, Well Control Incident Analaysis, EOG Resources Punnxsutawney Hunting Club 36 H, July 2010.

[8] Id

[9] Consent Order and Agreement, supra note 6

[10] See PA DEP, AB Resources – Marshall County Well Fire Incident (July 21, 2010), available at:

[11] Id

[12] Report on the Investigation of the Natural Gas Invasion of Aquifers in Bainbridge Township of Geauga County, Ohio (September 1, 2008), available at: See also Letter from John F. Husted, Chief of the Ohio Department of Natural Resources, Division of Mineral Resource Management (Aug. 28, 2008), available at:; Ohio Department of Natural Resources, Report on the Investigation of the Natural Gas Invasion in Bainbridge Township of Geauga County, Ohio (2008), available at:

[13] Id

[14] Ohio DNR, Order by the Chief to Ohio Valley Energy Systems Corp., Apr. 16, 2008, supra note 12  

[15] Letter from Robert C. Frey, Ph.D., Chief of the Health Assessment Section of the Ohio Bureau of Environmental Health, Ohio Department of Health to Scott Kell, Deputy Chief of the Ohio Department of Natural Resources Division of Mineral Resource Management (Sept. 10, 2008), available at and­bridge/10-31-08_resident_mailing_odh_letter.pdf

[16] Report on the Investigation of the Natural Gas Invasion of Aquifers in Bainbridge Township of Geauga County, Ohio (September 1, 2008), available at: See also Letter from John F. Husted, Chief of the Ohio Department of Natural Resources, Division of Mineral Resource Management (Aug. 28, 2008), available at:; Ohio Department of Natural Resources, Report on the Investigation of the Natural Gas Invasion in Bainbridge Township of Geauga County, Ohio (2008), available at:

[17] See PA DEP, Bureau of Oil and Gas Management, Stray Natural Gas Migration Associated with Oil and Gas Wells, Draft Report (December 28, 2009), available at:

[18] Id

[19] Id

[20] PA DEP, DEP Assesses Penalty for 2007 Gas Migration That Forced Evacuation in Erie County (July 8, 2009), available at:

[21] PA DEP Stray Natural Gas Migration Report, supra note 17

[22] PA DEP, DEP Identifies Responsibility for Bradford Township Gas Migration/Water Supply Problems (May 4, 2009), available at:

[23] Id

[24] PA DEP, DEP Orders Schreiner Oil and Gas to Restore Water Supplies at Two Homes in McKean County (February 25, 2010), available at:

[25] EPA grants extension for further testing of chromium contaminated area, Midland Reporter-Telegram, Dec. 3, 2009, available at:

[26] Texas Commission on Environmental Quality, Cleanup in Midland Couty: West County Road 112, Midland, TX,

[27] Texas Commission on Environmental Quality, TCEQ Holds Public Meeting on Water Well Contamination,; Texas

Commission on Environmental Quality, TCEQ Holds Public Meeting on Water Well Contamination,

[28] See NRDC, SWITCHBOARD, “Incidents where hydraulic fracturing is a suspected cause of drinking water contamination,”

[29] KLSA, We may now know what killed cows in Caddo Parish (May 2009), available at:

[30] Id

[31] EPA, Search Superfund Site Information, Pavillion Area Ground Water Study,



[34] See Brent Hubbard, Millions of Gallons Spilled in Colorado Over Two and a Half Year Period, Denver Post (June 28, 2010).

[35] Id

[36] Review of Phase II Hydrogeologic Study, Prepared for Garfield County. Geoffrey Tyne. Dec. 20, 2009.

[37] Colorado Oil and Gas Conservation Commission, FY 2008-2009 Report to the Water Quality Control Commission and Watery Quality Control Division of the Colorado Department of Public Health and Environment, Nov. 2009,

[38] Cadmus Group, Hydraulic Fracturing: Preliminary Analysis of Recently Reported Contamination, prepared for EPA (September 2009), on file with Riverkeeper

[39] 5 PA DEP, DEP Fines Atlas Resources for Drilling Wastewater Spill in Washington County (August 17, 2010), available at:

[40] PA DEP, DEP Fines Atlas $85,000 for Violations at 13 Well Sites (January 7, 2010), available at:

[41] 2 PA DEP, DEP Penalizes Range Resources $141,175 for Spill in High Quality Waterway (May 14, 2010), available at:

[42] PA DEP, DEP Fines Talisman Energy USA for Bradford County Drilling Wastewater Spill, Polluting Nearby Water Resource (August 2, 1010), available at:

[43] David O. Williams, “State Backlogged with Gas Contamination Cases Dating Back Years,” The Colorado Independent, May 11, 2010.

[44] See Dennis Webb, Energy Giant Agrees to Pay Record Fine, The Daily Sentinel (July 23, 2010).

[45] PA DEP, DEP Fines Fortuna Energy Inc. $3,500 for Well Drilling Violations in Bradford County (February 1, 2010), available at:

[46] WVDEP, WVDEP Concludes Investigation on Buckeye Creek (June 18, 2010), available at:

[47] PA DEP, DEP Investigates Source of Elevated Total Dissolved Solids in Monongahela River (Oct. 22, 2008), available at:

[48] New York City DEP, Rapid Impact Assessment Report (2009), available at: See also Notice of Violation Letter from Craig Lobbins, PA DEP Regional Manager, to Thomas Liberatore, Cabot Oil & Gas Corporation, Vice President (Feb. 27, 2009) (on file with Riverkeeper)

[49] Army Corps of Engineers letter to US EPA Region 3 (September 19, 2009), on file with Riverkeeper.

[50] PA DEP, DEP Detects Total Dissolved Solids Over Standards in Monongahela River (Oct. 14, 2009),

available at:


[51] Wolf Eagle Environmental, DISH Air Study Results, Sept. 15, 2009 at 9, available at, http://www.

[52] Texas Commission on Environmental Quality, Health Effects Review of Ambient Air Monitoring Data Collected by Wolf Eagle Environmental Engineers and Consultants for DISH, TX, October 27, 2009,

[53] Al Armendariz, Emissions from Natural Gas Production in Barnett Shale Area and Opportunities for Cost-Effective Improvements, Jan. 26, 2009,

[54] See PA DEP, DEP Continues to Analyze Dimock Water Supplies (Mar. 27, 2009), available at:, see also PA DEP, DEP Continuing Investigation Into High Methane Levels in Susquehanna County Wells (Jan. 23, 2009), available at:

[56] Id

[57] PA DEP, DEP Continues to Analyze Dimock Water Supplies supra note 22

[58] New York City DEP, Rapid Impact Assessment Report (2009), available at: See also Notice of Violation Letter from Craig Lobbins, PA DEP Regional Manager, to Thomas Liberatore, Cabot Oil & Gas Corporation , Vice President (Feb. 27, 2009) (on file with Riverkeeper).

[59] PA DEP Cabot Oil and Gas Consent Order and Agreement (November 4, 2009), available at:

[60] PA DEP, DEP Reaches Agreement with Cabot to Prevent Gas Migration, Restore Water Supplies in Dimock Township (Nov. 4, 2009), available at: 

[61] Dimock, PA: "Ground Zero" In The Fight Over Fracking

[62] PA DEP, DEP Issues Violation Notice to Cabot Oil and Gas, Company must properly clean up Susquehanna Gel Spill

[63] Id

[64] Id

[65] Id

[66] PA DEP Cabot Oil and Gas Consent Order and Agreement (November 4, 2009), available at:

[67] Id

[68] Id

[69] Id

[70] Id

[71] Id

[72] Id

[73] Id

[74] Id

[75] Id

[76] Id

[77] Id

[78] Id

[79] Id

[80] Id

[82] Id

[85] Id

[86] Id

[87] Id

[88] Id

[89] EPA: Summary report for 61 Dimock households that were sampled,2,3,4,5%20Compulation%20Report%202.pdf

[90] Id

[91] Id

[93] Environmentalists Lead Push for EPA to Reopen Dimock Water Study (August 13, 2013), available at:

[94] Id

[95] Id

[96] Susquehanna residents head to D.C., imploring EPA to return to Dimock. (August 13, 2013), available at:

[97] Id


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