Fracking Hollenbeck Gas Site
Gasland--The Movie-Sundance Film Festival (Q&A Session)
part two of Gasland Trailer
Fracking ("Earth Embalming") Fluid Ingredients List:
2634-33-5 1,2-Benzisothiazolin-2-one / 1,2-benzisothiazolin-3-one
10222-01-2 2,2 Dibromo-3-nitrilopropionamide, a biocide
15214-89-8 2-Acrylamido-2-methylpropane sulphonic acid sodium salt polymer
46830-22-2 2-acryloyloxyethyl(benzyl)dimethylammonium chloride
111-76-2 2-Butoxy ethanol
1113-55-9 2-Dibromo-3-Nitriloprionamide (2-Monobromo-3-nitriilopropionamide)
104-76-7 2-Ethyl Hexanol
67-63-0 2-Propanol / Isopropyl Alcohol / Isopropanol / Propan-2-ol
26062-79-3 2-Propen-1-aminium, N,N-dimethyl-N-2-propenyl-chloride, homopolymer
9003-03-6 2-propenoic acid, homopolymer, ammonium salt
25987-30-8 2-Propenoic acid, polymer with 2 p-propenamide, sodium salt / Copolymer of acrylamide and sodium acrylate
71050-62-9 2-Propenoic acid, polymer with sodium phosphinate (1:1)
66019-18-9 2-propenoic acid, telomer with sodium hydrogen sulfite
107-19-7 2-Propyn-1-ol / Propargyl alcohol
51229-78-8 3,5,7-Triaza-1-azoniatricyclo[220.127.116.11,7]decane, 1-(3-chloro-2-propenyl)-chloride,
127087-87-0 4-Nonylphenol Polyethylene Glycol Ether Branched / Nonylphenol ethoxylated / Oxyalkylated Phenol
64-19-7 Acetic acid
68442-62-6 Acetic acid, hydroxy-, reaction products with triethanolamine
108-24-7 Acetic Anhydride
38193-60-1 Acrylamide - sodium 2-acrylamido-2-methylpropane sulfonate copolymer
25085-02-3 Acrylamide - Sodium Acrylate Copolymer or Anionic Polyacrylamide
69418-26-4 Acrylamide polymer with N,N,N-trimethyl-2[1-oxo-2-propenyl]oxy Ethanaminium chloride
15085 -02-3 Acrylamide-sodium acrylate copolymer
68551-12-2 Alcohols, C12-C16, Ethoxylated (a.k.a. Ethoxylated alcohol)
64742-47-8 Aliphatic Hydrocarbon / Hydrotreated light distillate / Petroleum Distillates / Isoparaffinic Solvent / Paraffin Solvent / Napthenic Solvent
68439-57-6 Alkyl (C14-C16) olefin sulfonate, sodium salt
9016-45-9 Alkylphenol ethoxylate surfactants
1327-41-9 Aluminum chloride
73138-27-9 Amines, C12-14-tert-alkyl, ethoxylated
71011-04-6 Amines, Ditallow alkyl, ethoxylated
68551-33-7 Amines, tallow alkyl, ethoxylated, acetates
631-61-8 Ammonium acetate
68037-05-8 Ammonium Alcohol Ether Sulfate
7783-20-2 Ammonium bisulfate
10192-30-0 Ammonium bisulfite
12125-02-9 Ammonium chloride
7632-50-0 Ammonium citrate
37475-88-0 Ammonium Cumene Sulfonate
1341-49-7 Ammonium hydrogen-difluoride
6484-52-2 Ammonium nitrate
7727-54-0 Ammonium Persulfate / Diammonium peroxidisulphate
1762-95-4 Ammonium Thiocyanate
7664-41-7 Aqueous ammonia
121888-68-4 Bentonite, benzyl(hydrogenated tallow alkyl) dimethylammonium stearate complex / organophilic clay
119345-04-9 Benzene, 1,1'-oxybis, tetratpropylene derivatives, sulfonated, sodium salts
74153-51-8 Benzenemethanaminium, N,N-dimethyl-N-[2-[(1-oxo-2-propenyl)oxy]ethyl]-, chloride, polymer with 2-propenamide
10043-35-3 Boric acid
1303-86-2 Boric oxide / Boric Anhydride
68002-97-1 C10 - C16 Ethoxylated Alcohol
68131-39-5 C12-15 Alcohol, Ethoxylated
10043-52-4 Calcium chloride
124-38-9 Carbon dioxide
68130-15-4 Carboxymethylhydroxypropyl guar
9012-54-8 Cellulase / Hemicellulase Enzyme
10049-04-4 Chlorine dioxide
77-92-9 Citric Acid
94266-47-4 Citrus Terpenes
61789-40-0 Cocamidopropyl betaine
68155-09-9 Cocamidopropylamine Oxide
7758-98-7 Copper(II) sulfate
31726-34-8 Crissanol A-55
14808-60-7 Crystalline Silica (Quartz)
7447-39-4 Cupric chloride dihydrate
1120-24-7 Decyldimethyl Amine
2605-79-0 Decyl-dimethyl Amine Oxide
111-46-6 Diethylene glycol
22042-96-2 Diethylenetriamine penta (methylenephonic acid) sodium salt
28757-00-8 Diisopropyl naphthalenesulfonic acid
68607-28-3 Dimethylcocoamine, bis(chloroethyl) ether, diquaternary ammonium salt
7398-69-8 Dimethyldiallylammonium chloride
25265-71-8 Dipropylene glycol
139-33-3 Disodium Ethylene Diamine Tetra Acetate
27176-87-0 Dodecylbenzene sulfonic acid
42504-46-1 Dodecylbenzenesulfonate isopropanolamine
50-70-4 D-Sorbitol / Sorbitol
37288-54-3 Endo-1,4-beta-mannanase, or Hemicellulase
149879-98-1 Erucic Amidopropyl Dimethyl Betaine
89-65-6 Erythorbic acid, anhydrous
54076-97-0 Ethanaminium, N,N,N-trimethyl-2-[(1-oxo-2-propenyl)oxy]-, chloride, homopolymer
107-21 -1 Ethane-1,2-diol / Ethylene Glycol
9002-93-1 Ethoxylated 4-tert-octylphenol
68439-50-9 Ethoxylated alcohol
126950-60-5 Ethoxylated alcohol
67254-71-1 Ethoxylated alcohol (C10-12)
68951-67-7 Ethoxylated alcohol (C14-15)
68439-46-3 Ethoxylated alcohol (C9-11)
66455-15-0 Ethoxylated Alcohols
84133-50-6 Ethoxylated Alcohols (C12-14 Secondary)
68439-51-0 Ethoxylated Alcohols (C12-14)
78330-21-9 Ethoxylated branch alcohol
34398-01-1 Ethoxylated C11 alcohol
61791-12-6 Ethoxylated Castor Oil
61791-29-5 Ethoxylated fatty acid, coco
61791-08-0 Ethoxylated fatty acid, coco, reaction product with ethanolamine
68439-45-2 Ethoxylated hexanol
9036-19-5 Ethoxylated octylphenol
9005-67-8 Ethoxylated Sorbitan Monostearate
9004-70-3 Ethoxylated Sorbitan Trioleate
64-17-5 Ethyl alcohol / ethanol
100-41-4 Ethyl Benzene
97-64-3 Ethyl lactate
9003-11-6 Ethylene Glycol-Propylene Glycol Copolymer (Oxirane, methyl-, polymer with oxirane)
75-21-8 Ethylene oxide
68526-86-3 Exxal 13
61790-12-3 Fatty Acids
68188-40-9 Fatty acids, tall oil reaction products w/ acetophenone, formaldehyde & thiourea
9043-30-5 Fatty alcohol polyglycol ether surfactant
7705-08-0 Ferric chloride
7782-63-0 Ferrous sulfate, heptahydrate
29316-47-0 Formaldehyde polymer with 4,1,1-dimethylethyl phenolmethyl oxirane
153795-76-7 Formaldehyde, polymers with branched 4-nonylphenol, ethylene oxide and propylene oxide
64-18-6 Formic acid
110-17-8 Fumaric acid
65997-17-3 Glassy calcium magnesium phosphate
56-81-5 Glycerol / glycerine
9000-30-0 Guar Gum
64742-94-5 Heavy aromatic petroleum naphtha
7647-01-0 Hydrochloric Acid / Hydrogen Chloride / muriatic acid
7722-84-1 Hydrogen peroxide
79-14-1 Hydroxy acetic acid
35249-89-9 Hydroxyacetic acid ammonium salt
9004-62-0 Hydroxyethyl cellulose
5470-11-1 Hydroxylamine hydrochloride
39421-75-5 Hydroxypropyl guar
35674-56-7 Isomeric Aromatic Ammonium Salt
64742-88-7 Isoparaffinic Petroleum Hydrocarbons, Synthetic
98-82-8 Isopropylbenzene (cumene)
68909-80-8 Isoquinoline, reaction products with benzyl chloride and quinoline
64742-81-0 Kerosine, hydrodesulfurized
64742-95-6 Light aromatic solvent naphtha
1120-21-4 Light Paraffin Oil
14807-96-6 Magnesium Silicate Hydrate (Talc)
1184-78-7 methanamine, N,N-dimethyl-, N-oxide
68891-11-2 Methyloxirane polymer with oxirane, mono (nonylphenol) ether, branched
8052-41-3 Mineral spirits / Stoddard Solvent
44992-01-0 N,N,N-trimethyl-2[1-oxo-2-propenyl]oxy Ethanaminium chloride
64742-48-9 Naphtha (petroleum), hydrotreated heavy
38640-62-9 Naphthalene bis(1-methylethyl)
93-18-5 Naphthalene, 2-ethoxy-
68909-18-2 N-benzyl-alkyl-pyridinium chloride
7727-37-9 Nitrogen, Liquid form
68412-54-4 Nonylphenol Polyethoxylate
121888-66-2 Organophilic Clays
64742-65-0 Petroleum Base Oil
64741-68-0 Petroleum naphtha
70714-66-8 Phosphonic acid, [[(phosphonomethyl)imino]bis[2,1-ethanediylnitrilobis(methylene)]]tetrakis-, ammonium salt
8000-41-7 Pine Oil
60828-78-6 Poly(oxy-1,2-ethanediyl), a-[3,5-dimethyl-1-(2-methylpropyl)hexyl]-w-hydroxy-
25322-68-3 Poly(oxy-1,2-ethanediyl), a-hydro-w-hydroxy / Polyethylene Glycol
24938-91-8 Poly(oxy-1,2-ethanediyl), α-tridecyl-ω-hydroxy-
51838-31-4 Polyepichlorohydrin, trimethylamine quaternized
56449-46-8 Polyethlene glycol oleate ester
62649-23-4 Polymer with 2-propenoic acid and sodium 2-propenoate
9005-65-6 Polyoxyethylene Sorbitan Monooleate
61791-26-2 Polyoxylated fatty amine salt
127-08-2 Potassium acetate
12712-38-8 Potassium borate
1332-77-0 Potassium borate
20786-60-1 Potassium Borate
584-08-7 Potassium carbonate
7447-40-7 Potassium chloride
590-29-4 Potassium formate
1310-58-3 Potassium Hydroxide
13709-94-9 Potassium metaborate
24634-61-5 Potassium sorbate
112926-00-8 Precipitated silica / silica gel
57-55-6 Propane-1,2-diol, or Propylene glycol
107-98-2 Propylene glycol monomethyl ether
68953-58-2 Quaternary Ammonium Compounds
62763-89-7 Quinoline,2-methyl-, hydrochloride
15619-48-4 Quinolinium, 1-(phenylmethl),chloride
7631-86-9 Silica, Dissolved
5324-84-5 Sodium 1-octanesulfonate
127-09-3 Sodium acetate
95371-16-7 Sodium Alpha-olefin Sulfonate
532-32-1 Sodium benzoate
144-55-8 Sodium bicarbonate
7631-90-5 Sodium bisulfate
7647-15-6 Sodium bromide
497-19-8 Sodium carbonate
7647-14-5 Sodium Chloride
7758-19-2 Sodium chlorite
3926-62-3 Sodium chloroacetate
68-04-2 Sodium citrate
6381-77-7 Sodium erythorbate / isoascorbic acid, sodium salt
2836-32-0 Sodium Glycolate
1310-73-2 Sodium Hydroxide
7681-52-9 Sodium hypochlorite
7775-19-1 Sodium Metaborate .8H2O
10486-00-7 Sodium perborate tetrahydrate
7775-27-1 Sodium persulfate
9003-04-7 Sodium polyacrylate
7757-82-6 Sodium sulfate
1303-96-4 Sodium tetraborate decahydrate
7772-98-7 Sodium thiosulfate
1338-43-8 Sorbitan Monooleate
5329-14-6 Sulfamic acid
112945-52-5 Synthetic Amorphous / Pyrogenic Silica / Amorphous Silica
68155-20-4 Tall Oil Fatty Acid Diethanolamine
8052-48-0 Tallow fatty acids sodium salt
72480-70-7 Tar bases, quinoline derivs., benzyl chloride-quaternized
68647-72-3 Terpene and terpenoids
68956-56-9 Terpene hydrocarbon byproducts
533-74-4 Tetrahydro-3,5-dimethyl-2H-1,3,5-thiadiazine-2-thione (a.k.a. Dazomet)
55566-30-8 Tetrakis(hydroxymethyl)phosphonium sulfate (THPS)
75-57-0 Tetramethyl ammonium chloride
64-02-8 Tetrasodium Ethylenediaminetetraacetate
68-11-1 Thioglycolic acid
68527-49-1 Thiourea, polymer with formaldehyde and 1-phenylethanone
81741-28-8 Tributyl tetradecyl phosphonium chloride
68299-02-5 Triethanolamine hydroxyacetate
112-27-6 Triethylene glycol
52624-57-4 Trimethylolpropane, Ethoxylated, Propoxylated
150-38-9 Trisodium Ethylenediaminetetraacetate
5064-31-3 Trisodium Nitrilotriacetate
7601-54-9 Trisodium orthophosphate
25038-72-6 Vinylidene Chloride/Methylacrylate Copolymer
Aliphatic alcohol glycol ether
Alkyl Aryl Polyethoxy Ethanol
Petroleum distillate blend
Salt of amine-carbonyl condensate
Salt of fatty acid/polyamine reaction product
Fractures may form naturally, as in the case of veins or dikes, or may be man-made in order to release petroleum, natural gas, coal seam gas, or other substances for extraction, where the technique is often called fracking[a] or hydrofracking. This type of fracturing, known colloquially as a frack job (or frac job), is done from a wellbore drilled into reservoir rock formations. The energy from the injection of a highly-pressurized fracking fluid, creates new channels in the rock which can increase the extraction rates and ultimate recovery of fossil fuels. The fracture width is typically maintained after the injection by introducing a proppant into the injected fluid. Proppant is a material, such as grains of sand, ceramic, or other particulates, that prevent the fractures from closing when the injection is stopped.
The practice of hydraulic fracturing has come under scrutiny internationally due to apparent concerns about the environment, health and safety, and has been suspended or banned in some countries.
Fracturing in rocks at depth is suppressed by the confining pressure, particularly in the case of tensile (Mode 1) fractures which require the walls of the fracture to move apart. Hydraulic fracturing occurs when the effective stress is reduced sufficiently by an increase in the pressure of fluids in the rock such that the minimum principal stress becomes tensile and exceeds the tensile strength of the material. Fractures formed in this way will typically be orientated perpendicular to the minimum principal stress and for this reason, induced hydraulic fractures in wellbores are sometimes used to determine stress orientations. In natural examples, such as dikes or vein-filled fractures, their orientations can be used to infer past stress states .
Most vein systems are a result of repeated hydraulic fracturing during periods of relatively high pore fluid pressure. This is particularly clear in the case of 'crack-seal' veins, where the vein material can be seen to have been added in a series of discrete fracturing events, with extra vein material deposited on each occasion. One mechanism to explain such examples of long-lasting repeated fracturing, is the effects of seismic activity, in which the stress levels rise and fall episodically and large volumes of fluid may be expelled from fluid-filled fractures during earthquakes, a process referred to as 'seismic pumping'.
High-level minor intrusions such as dikes propagate through the crust in the form of fluid-filled cracks, although in this case the fluid is magma. In sedimentary rocks with a significant water content the fluid at the propagating fracture tip will be steam.
Induced hydraulic fracturing
The technique of hydraulic fracturing is used to increase or restore the rate at which fluids, such as oil, water, or natural gas can be produced from subterranean natural reservoirs. Reservoirs are typically porous sandstones, limestones or dolomite rocks, but also include 'unconventional reservoirs' such as shale rock or coal beds. Hydraulic fracturing enables the production of natural gas and oil from rock formations deep below the earth's surface (generally 5,000-20,000 feet or 1,500-6,100 m). At such depth, there may not be sufficient porosity, permeability or reservoir pressure to allow natural gas and oil to flow from the rock into the wellbore at economic rates. Thus, creating conductive fractures in the rock is essential to extract gas from shale reservoirs because of the extremely low natural permeability of shale, which is measured in the microdarcy to nanodarcy range. Fractures provide a conductive path connecting a larger area of the reservoir to the well, thereby increasing the area from which natural gas and liquids can be recovered from the targeted formation.
While the main industrial use of hydraulic fracturing is in stimulating production from oil and gas wells, hydraulic fracturing is also applied to:
Stimulating groundwater wells
Preconditioning rock for caving or inducing rock to cave in mining
As a means of enhancing waste remediation processes, usually hydrocarbon waste or spills
Dispose of waste by injection into deep rock formations
As a method to measure the stress in the earth
For heat extraction to produce electricity in an Enhanced Geothermal System 
A hydraulic fracture is formed by pumping the fracturing fluid into the wellbore at a rate sufficient to increase pressure downhole to exceed that of the fracture gradient of the rock. The rock cracks and the fracture fluid continues farther into the rock, extending the crack still farther, and so on. To keep this fracture open after the injection stops, a solid proppant, commonly a sieved round sand, is added to the fluid. The propped fracture is permeable enough to allow the flow of formation fluids to the well. Formation fluids include gas, oil, salt water, fresh water and fluids introduced to the formation during completion of the well during fracturing.
The location of one or more fractures along the length of the borehole is strictly controlled by various different methods which create or seal-off holes in the side of the wellbore. Typically, hydraulic fracturing is performed in cased wellbores and the zones to be fractured are accessed by perforating the casing at those locations.
While hydraulic fracturing is many times performed in vertical wells, today it is also performed in horizontal wells. Horizontal drilling involves wellbores where the terminal drillhole is completed as a 'lateral' that extends parallel with the rock layer containing the substance to be extracted. For example, laterals extend 1,500 to 5,000 feet in the Barnett Shale basin in Texas, and up to 10,000 feet in the Bakken formation in North Dakota. In contrast, a vertical well only accesses the thickness of the rock layer, typically 50–300 feet. Horizontal drilling also reduces surface disruptions as fewer wells are required. Drilling usually induces damage to the pore space at the wellbore wall, reducing the permeability at and near the wellbore. This reduces flow into the borehole from the surrounding rock formation, and partially seals off the borehole from the surrounding rock. Hydraulic fracturing can be used to restore permeability.
Hydraulic fracturing is commonly applied to wells drilled in low permeability reservoir rock. An estimated 90 percent of the natural gas wells in the United States use hydraulic fracturing to produce gas at economic rates.
The fluid injected into the rock is typically a slurry of water, proppants, and chemical additives. Additionally, gels, foams, and compressed gases, including nitrogen, carbon dioxide and air can be injected. Various types of proppant include silica sand, resin-coated sand, and man-made ceramics. These vary depending on the type of permeability or grain strength needed. Sand containing naturally radioactive minerals is sometimes used so that the fracture trace along the wellbore can be measured. Chemical additives are applied to tailor the injected material to the specific geological situation, protect the well, and improve its operation, though the injected fluid is approximately 98-99.5% percent water, varying slightly based on the type of well. The composition of injected fluid is sometimes changed as the fracturing job proceeds. Often, acid is initially used to scour the perforations and clean up the near-wellbore area. Then proppants are used with a gradual increase in their size and/or density. At the end of the job the well is commonly flushed with water (sometimes blended with a friction reducing chemical) under pressure. Injected fluid is to some degree recovered and is managed by several methods, such as underground injection control, treatment and discharge, recycling, or temporary storage in pits or containers while new technology is being developed to better handle wastewater and improve reusability. Although the concentrations of the chemical additives are very low, the recovered fluid may be harmful due in part to hydrocarbons picked up from the formation.
Hydraulic fracturing equipment used in oil and natural gas fields usually consists of a slurry blender, one or more high pressure, high volume fracturing pumps (typically powerful triplex, or quintiplex pumps) and a monitoring unit. Associated equipment includes fracturing tanks, one or more units for storage and handling of proppant, high pressure treating iron, a chemical additive unit (used to accurately monitor chemical addition), low pressure flexible hoses, and many gauges and meters for flow rate, fluid density, and treating pressure. Fracturing equipment operates over a range of pressures and injection rates, and can reach up to 100 MPa (15,000 psi) and 265 L/s (100 barrels per minute).
Measurements of the pressure and rate during the growth of a hydraulic fracture, as well as knowing the properties of the fluid and proppant being injected into the well provides the most common and simplest method of monitoring a hydraulic fracture treatment. This data, along with knowledge of the underground geology can be used to model information such as length, width and conductivity of a propped fracture.
For more advanced applications, Microseismic monitoring is sometimes used to estimate the size and orientation of hydraulically induced fractures. Microseismic activity is measured by placing an array of geophones in a nearby wellbore. By mapping the location of any small seismic events associated with the growing hydraulic fracture, the approximate geometry of the fracture is inferred. Tiltmeter arrays, deployed on the surface or down a well, provide another technology for monitoring the strains produced by hydraulic fracturing.
Emission of gases displaced by hydraulic fracturing into the atmosphere may be detected via atmospheric gas monitoring, and can be quantified directly via the eddy covariance flux measurements.
Since the early 2000s, advances in drilling and completion technology has made drilling horizontal wellbores much more economical. Horizontal wellbores allow for far greater exposure to a formation than a conventional vertical wellbore. This is particularly useful in shale oil and gas formations which do not have sufficient permeability to produce economically with a vertical well. Such wells when drilled onshore are now usually hydraulically fractured many times, especially in North America. The type of wellbore completion used will affect how many times the formation is fractured, and at what locations along the horizontal section of the wellbore.
In North America, tight reservoirs such as the Bakken, Barnett Shale, Montney and Haynesville Shale are drilled, completed and fractured using this method. The method by which the fractures are placed along the wellbore is most commonly achieved by one of two methods, known as 'plug and perf' and 'sliding sleeve'.
The wellbore for a plug and perf job is generally composed of standard joints of steel casing, either cemented or uncemented, which is set in place at the conclusion of the drilling process. Once the drilling rig has been removed, a wireline truck is used to perforate near the end of the well, following which a fractuing job is pumped (commonly called a stage). Once the stage is finished, the wireline truck will set a plug in the well to temporarily seal off the that section, and then perforate the next section of the wellbore. Another stage is then pumped, and the process is repeated as necessary along the entire length of the horizontal part of the wellbore.
The wellbore for the sliding sleeve technique is different in that the sliding sleeves are included at set spacings in the steel casing at the time it is set in place. The sliding sleeves are usually all closed at this time. When the well is ready to be fractured, using one of several activation techniques, the bottom sliding sleeve is opened and the first stage gets pumped. Once finished, the next sleeve is opened which concurrently isolates the first stage, and the process repeats. For the sliding sleeve method, wireline is usually not required.
These completion techniques may allow for more than 30 stages to be pumped into the horizontal section of a single well if required, which is far more than would typically be pumped into a vertical well.
The pressure to fracture the formation at a particular depth divided by the depth. A fracture gradient of 18 kPa/m (0.8 psi/foot) implies that at a depth of 3 km (10,000 feet) a pressure of 54 MPa (8,000 psi) will extend a hydraulic fracture.
ISIP - Initial Shut In Pressure
The pressure measured immediately after injection stops. The ISIP provides a measure of the pressure in the fracture at the wellbore by removing contributions from fluid friction.
Loss of fracturing fluid from the fracture channel into the surrounding permeable rock.
The fluid used during a hydraulic fracture treatment of oil, gas or water wells. The fracturing fluid has two major functions:
Open and extend the fracture
Transport the proppant along the fracture length.
Suspended particles in the fracturing fluid that are used to hold fractures open after a hydraulic fracturing treatment, thus producing a conductive pathway that fluids can easily flow along. Naturally occurring sand grains or artificial ceramic material are common proppants used.
"Fracing" (sometimes spelled "fracking" primarily in media) is a shortened version of fracturing.
Environmental concerns with hydraulic fracturing include the potential contamination of ground water, risks to air quality, the potential migration of gases and hydraulic fracturing chemicals to the surface, the potential mishandling of waste, and the health effects of these. A 2004 study by the Environmental Protection Agency (EPA) concluded that the injection of hydraulic fracturing fluids into CBM wells posed minimal threat to underground drinking water sources. This study has been criticised for only focusing on the injection of fracking fluids, while ignoring other aspects of the process such as disposal of fluids, and environmental concerns such as water quality, fish kills and acid burns; the study was also concluded before public complaints of contamination started emerging.:780 Largely on the basis of this study, in 2005 hydraulic fracturing was exempted by US Congress from any regulation under the Safe Drinking Water Act.
With the explosive growth of natural gas wells in the US, researcher Valerie Brown predicted in 2007 that "public exposure to the many chemicals involved in energy development is expected to increase over the next few years, with uncertain consequences." As development of natural gas wells in the U.S. since the year 2000 has increased, so too have claims by private well owners of water contamination. This has prompted EPA and others to re-visit the topic.
While the EPA recognizes the potential for contamination of water by hydraulic fracturing, EPA Administrator Lisa Jackson testified in a Senate Hearing Committee "I'm not aware of any proven case where the fracking process itself has affected water...". There are, however, documented incidents of contamination. In 2006 drilling fluids and methane were detected leaking from the ground near a gas well in Clark, Wyoming; 8 million cubic feet of methane were eventually released, and shallow groundwater was found to be contaminated. In the town of Dimock, Pennsylvania, 13 water wells were contaminated with methane (one of them blew up), and the gas company, Cabot Oil & Gas, had to financially compensate residents and construct a pipeline to bring in clean water; the company continued to deny, however, that any "of the issues in Dimock have anything to do with hydraulic fracturing".
Air emissions and pollution
One group of emissions associated with natural gas development and production, are the emissions associated with combustion. These emissions include particulate matter, nitrogen oxides, sulfur oxide, carbon dioxide and carbon monoxide. Another group of emissions that are routinely vented into the atmosphere are those linked with natural gas itself, which is composed of methane, ethane, liquid condensate, and volatile organic compounds (VOCs). The VOCs that are especially impactful on health are benzene, toluene, ethyl benzene, and xylene (referred to as a group, called BTEX). Health effects of exposure to these chemicals include neurological problems, birth defects, and cancer.
VOCs, including BTEX, mixed with nitrogen oxides from combustion and combined with sunlight can lead to ozone formation. Ozone has been shown to impact lung function, increase respiratory illness, and is particularly dangerous to lung development in children. In 2008, measured ambient concentrations in the rural Sublette County Wyoming where ranching and natural gas are the main industries were frequently above the National Ambient Air Quality Standards (NAAQS) of 75ppb and have been recorded as high as 125 ppb.
A Duke University study published in Proceedings of the National Academy of Sciences in 2011 examined methane in groundwater in Pennsylvania and New York states overlying the Marcellus Shale and the Utica Shale. It determined that groundwater tended to contain much higher concentrations of methane near fracking wells, with potential explosion hazard; the methane's isotopic signatures and other geochemical indicators were consistent with it originating in the fracked deep shale formations, rather than any other source. Complaints from a few residents on water quality in a developed natural gas field prompted an EPA groundwater investigation in Wyoming. The EPA reported detections of methane and other chemicals such as phthalates in private water wells.
In Pavillion, Wyoming, the EPA discovered traces of methane and foaming agents in several water wells near a gas rig, though it suggested these chemicals might have come from cleaning products. In DISH, Texas, elevated levels of disulphides, benzene, xylenes and naphthalene have been detected in the air, alongside numerous local complaints of headaches, diarrhea, nosebleeds, dizziness, muscle spasms and other problems.
Groundwater contamination doesn't come directly from injecting fracking chemicals deep into Shale rock formations well below water aquifers but from waste water evaporation ponds and poorly constructed pipelines taking the waste water and chemicals to processing facilities. The evaporation ponds allow the volatile chemicals in the waste water to evaporate into the atmosphere and when it rains these ponds tend to overflow and the runoff eventually makes its way into groundwater systems. Another way groundwater gets contaminated relating to fracking is from the temporary, and poorly constructed pipelines to transport the waste water to water treatment plants. These pipelines can leak and in come cases break in a section all together allowing the waste water and fracking chemicals to flow into groundwater systems. The transportation by trucks and storage of fracking chemicals allows for groundwater to become contaminated when accidents happen during transportation to the fracking site or to its disposal destination.
Epidemiological studies that might confirm or rule out any connection between these complaints and fracking are virtually non-existent. Individuals "smell things that don't make them feel well, but we know nothing about cause-and-effect relationships in these cases." 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. The health effects of VOCs are largely unquantified, so any causal relationship is difficult to ascertain; however, some of these chemicals are suspected carcinogens and neurotoxins. Investigators from the Colorado School of Public Health performed a study in Garfield regarding potential adverse health effects, and concluded that residents near gas wells might suffer chemical exposures, accidents from industry operations, and psychological impacts such as depression, anxiety and stress. This study (the only one of its kind to date) was never published, owing to disagreements between community members and the drilling company over the study's methods.
In 2010 the film Gasland premiered at the Sundance Film Festival. The filmmaker claims that chemicals including toxins, known carcinogens, and heavy metals polluted the ground water near well sites in Pennsylvania, Wyoming, and Colorado.
A 2011 report by the Massachusetts Institute of Technology addressed groundwater contamination, noting "There has been concern that these fractures can also penetrate shallow freshwater zones and contaminate them with fracturing ﬂuid, but there is no evidence that this is occurring. There is, however, evidence of natural gas migration into freshwater zones in some areas, most likely as a result of substandard well completion practices by a few operators. There are additional environmental challenges in the area of water management, particularly the effective disposal of fracture fluids". This study encourages the use of industry best practices to prevent such events from recurring.
Directed by Congress, the U.S. EPA announced in March 2010 that it will examine claims of water pollution related to hydraulic fracturing.
The New York Times has reported radiation in hydraulic fracturing wastewater released into rivers in Pennsylvania. According to a Times report in February 2011, wastewater at 116 of 179 deep gas wells in Pennsylvania "contained high levels of radiation," but its effect on public drinking water supplies is unknown because water suppliers are required to conduct tests of radiation "only sporadically". The Times stated "never-reported studies" by the EPA and a "confidential study by the drilling industry" concluded that radioactivity in drilling waste cannot be fully diluted in rivers and other waterways. Despite this, as of early 2011 federal and state regulators did not require sewage treatment plants that accept drilling waste (which is mostly water) to test for radioactivity. In Pennsylvania, where the drilling boom began in 2008, most drinking-water intake plants downstream from those sewage treatment plants have not tested for radioactivity since before 2006.
The New York Post stated that the Pennsylvania Department of Environmental Protection reported that all samples it took from seven rivers in November and December 2010 "showed levels at or below the normal naturally occurring background levels of radioactivity", and "below the federal drinking water standard for Radium 226 and 228.". However the samples taken by the state at at least one river, (the Monongahela, a source of drinking water for parts of Pittsburgh), were taken upstream from the sewage treatment plants accepting drilling waste water. Furthermore, the New York Times has implicated the DEP in industry-friendly inactivity, such as only making a "request — not a regulation" of gas companies to handle their own flowback waste rather than sending them to public water treatment facilities.
Chemicals used in fracturing
Water is by far the largest component of fracking fluids. The initial drilling operation itself may consume from 65,000 gallons to 600,000 gallons of fracking fluids. Over its lifetime an average well will require up to an additional 5 million gallons of water for the initial fracking operation and possible restimulation frac jobs.
Chemical additives used in fracturing fluids typically make up less than 2% by weight of the total fluid. Over the life of a typical well, this may amount to 100,000 gallons of chemical additives. They are biocides, surfactants, adjusting viscosity, and emulsifiers. Many are used in household products such as cosmetics, lotions, soaps, detergents, furniture polishes, floor waxes, and paints. Some are also used in food products. A list of the chemicals that have been used was published in a U.S. House of Representatives Report. Some of the chemicals pose no known health hazards, some others are known carcinogens, some are toxic, some are neurotoxins. For example: benzene (causes cancer, bone marrow failure), lead (damages the nervous system and causes brain disorders), ethylene glycol (antifreeze, causes death), methanol (highly toxic), boric acid (kidney damage, death), 2-butoxyethanol (causes hemolysis).
The 2011 US House of Representatives investigative report on the chemicals used in hydraulic fracturing shows that of the 750 compounds in hydraulic fracturing products “[m]ore than 650 of these products contained chemicals that are known or possible human carcinogens, regulated under the Safe Drinking Water Act, or listed as hazardous air pollutants” (12). The report also shows that between 2005 and 2009 279 products (93.6 million gallons-not including water) had at least one component listed as “proprietary” or “trade secret” on their Occupational Safety and Health Administration (OSHA) required Material Safety Data Sheet (MSDS).
The MSDS is a list of chemical components in the products of chemical manufacturers, and according to OSHA, a manufacturer may withhold information designated as “proprietary” from this sheet. When asked to reveal the proprietary components, most companies participating in the investigation were unable to do so, leading the committee to surmise these “companies are injecting fluids containing unknown chemicals about which they may have limited understanding of the potential risks posed to human health and the environment” (12). Third-party laboratories are performing analysis on soil, air, and water near the fracturing sites to measure the level of contamination by each of the chemicals. Each state has a contact person in charge of such regulation.  A map of these contact people can be found at FracFocus.org as well.
Another study in 2011, titled “Natural Gas Operations from a Public Health Perspective” and published in Human and Ecological Risk Assessment: An International Journal identified 632 chemicals used in natural gas operations. Only 353 of these are well-described in the scientific literature; and of these, more than 75% could affect skin, eyes, respiratory and gastrointestinal systems; roughly 40-50% could affect the brain and nervous, immune and cardiovascular systems and the kidneys; 37% could affect the endocrine system; and 25% were carcinogens and mutagens. The study indicated possible long-term health effects that might not appear immediately. The study recommended full disclosure of all products used, along with extensive air and water monitoring near natural gas operations; it also recommended that fracking's exemption from regulation under the US Safe Drinking Water Act be rescinded.
A report in the UK concluded that fracking was the likely cause of some small earth tremors that happened during shale gas drilling. In addition the United States Geological Survey (USGS) reports that "Earthquakes induced by human activity have been documented in a few locations" in the United States, Japan, and Canada; "the cause was injection of fluids into deep wells for waste disposal and secondary recovery of oil, and the use of reservoirs for water supplies." The disposal and injection wells referenced are regulated under the Safe Drinking Water Act and UIC laws and are not wells where hydraulic fracturing is generally performed.
Greenhouse gas emissions
The use of natural gas rather than oil or coal is sometimes touted as a way of alleviating global warming: natural gas burns more cleanly, and gas power stations can produce up to 50% less greenhouse gases than coal stations. However, an analysis of the well-to-consumer lifecycle of fracked natural gas concluded that 3.6–7.9% of the methane produced by a well will be leaked into the atmosphere during the well's lifetime. Because methane is such a potent greenhouse gas, this means that over short timescales, shale gas is actually worse than coal or oil. Methane gradually breaks down in the atmosphere, forming carbon dioxide, so that over very long periods it is no more problematic than carbon dioxide; in the meantime, even if shale gas is burnt in efficient gas power stations, its greenhouse-gas footprint is still worse than coal or oil for timescales of less than fifty years.
The considerable opposition against fracking activities in local townships has led companies to adopt a variety of public relations measures to assuage fears about fracking, including the admitted use of "mil i tary tac tics to counter drilling opponents". At a conference where public relations measures were discussed, a senior executive at Anadarko Petroleum was recorded on tape saying, "Download the US Army / Marine Corps Counterinsurgency Manual, because we are dealing with an insurgency", while referring to fracking opponents. Matt Pitzarella, spokesman for the most important fracking company in Pennsylvania, Range Resources, also told other conference attendees that Range employed psychological warfare operations veterans. According to Pitzarella, the experience learnt in the Middle East has been valuable to Range Resources in Pennsylvania, when dealing with emotionally-charged township meetings and advising townships on zoning and local ordinances dealing with fracking.
Hydraulic fracturing by country
Hydraulic fracturing has become a contentious environmental and health issue with France banning the practice and a moratorium in place in New South Wales (Australia), Karoo basin (South Africa), Quebec (Canada), and some of the states of the US.
Up until the mid 2000s, hydraulic fracturing was generally limited to conventional oil and gas wells in the Cooper Basin and limited to one, two or sometimes zero ongoing fracturing operations. However more recently, it has spread and grown in Queensland as coal seam gas drilling and production in the Surat and Bowen basins has rapidly increased. However the vast majority of coal seam gas wells have not been hydraulically fractured as the wells presently being drilled are in coal seams that have good natural permeability.
On 21 February 2011, the ABC's investigative journalism program Four Corners aired a program showing incidents of wellhead gas leaks (unrelated to hydraulic fracturing) and alleged aquifer contamination near Chinchilla, Queensland at wells owned by QGC, some of which had been hydraulically fractured.
There is currently a moratorium in place on the practice of hydraulic fracturing in the state of New South Wales.. The moratorium will not affect exploration, drilling core holes and getting core samples. The NSW Government's restrictions on hydraulic fracturing apply to new licences only. The NSW Government has banned BTEX chemicals as additives. It also requires companies to hold a water licences for extraction of more than three megalitres per year and has banned the use of evaporation ponds.
Fracking has been in use in Canada at an industrial level since the 1990s. Concerns about fracking began in late July 2011, when the Government of British Columbia gave Talisman Energy a long-term water licence to draw water from the BC Hydro-owned Williston Lake reservoir, for a twenty year term. Fracking has also received criticism in New Brunswick and Nova Scotia, and the Nova Scotia government is currently reviewing the practice, with recommendations expected in March 2012. The practice has been temporarily suspended, in Quebec, pending an environmental review. The Canadian Centre for Policy Alternatives has also expressed concern.
Hydraulic fracturing was banned in France in 2011 after public pressure.
In New Zealand, hydraulic fracturing is part of petroleum exploration and extraction on a small scale mainly in Taranaki and concerns have been raised by environmentalists.
There is currently a moratorium on hydraulic fracturing in South Africa's Karoo region despite the interest of several energy companies.
Hydraulic fracturing is currently proceeding in the United Kingdom operated by Cuadrilla and a number of other companies. In Lancashire, operations were suspended after two small earthquakes subsequent to drilling operations.
Several protest groups have started to oppose hydraulic fracturing in the UK such as nationwide groups like Frack Off and local groups like Ribble Estuary Against Fracking and The Vale Says No 
Main article: Hydraulic fracturing in the United States
Hydraulic fracturing for the purpose of oil, natural gas, and geothermal production was exempted under the Safe Drinking Water Act. This was a result of the signage of the Energy Policy Act of 2005, also known as the Halliburton Loophole because of former Halliburton CEO Vice President D*** Cheney’s involvement in the passing of this exemption. The result of a 2004 EPA study on coalbed hydraulic fracturing was used to justify the passing of the exemption; however EPA whistleblower Weston Wilson and the Oil and Gas Accountability Project found that critical information was removed from the final report.
Opposers of hydraulic fracturing in the US have focused on this 2005 exemption; however the more primary risk to drinking water is the handling and treatment of wastewater produced by hydraulic fracturing. The EPA and the state authorities do have power “to regulate discharge of produced waters from hydraulic operations” (EPA, 2011) under the Clean Water Act, which is regulated by the National Pollutant Discharge Elimination System (NPDES) permit program "Treatment and Disposal of Wastewater from Shale Gas Extraction | NPDES."www.epa.gov/npdes. Environmental Protection Agency, n.d. Web. 15 Oct. 2011. a href="http://cfpub.epa.gov/npdes/hydrofracturing.cfm">http://cfpub.epa.gov/npdes/hydrofracturing.cfm>;.. Although this waste is regulated, oil and gas exploration and production (E&P) wastes are exempt from Federal Hazardous Waste Regulations under Subtitle C of the Resource Conservation and Recovery Act (RCRA) despite the fact that wastewater from hydraulic fracturing contains toxins such as total dissolved solids (TDS), metals, and radionuclides. About 750 chemicals have been listed as additives for hydraulic fracturing in a report to the US Congress in 2011. </<a href="http://cfpub.epa.gov/npdes/hydrofracturing.cfm">http://cfpub.epa.gov/npdes/hydrofracturing.cfm>;
Gasland, a 2010 documentary by Josh Fox claim that hydraulic fracturing has many environmental impacts
Eddy covariance, a method to directly measure emissions of gases displayed by hydraulic fracturing into the atmosphere
Cost of electricity by source
Environmental impact of the oil shale industry
Environmental impact of petroleum
Environmental concerns with electricity generation
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