What is hydraulic fracking?
Hydraulic fracturing, also known as fracking, is a process used by natural gas drilling companies to break up shale rock deep below the surface of the Earth, where shale natural gas is trapped. Hydraulic fracking is not new, but actually goes back to about 1860. In those days, they used nitroglycerin to stimulate shallow, hard rock wells. Fracking has also been used with oil wells over the years to increase oil production.
What is new to fracking is the high water pressure that is used to fracture the rock. Much of modern day fracking is used to retrieve natural gas from shale. Without fracking, shale gas has very little potential. With fracking, the discovery of this shale gas offers a very bright future for natural gas and for America’s release from its dependency on foreign fuel.
Unfortunately, there is a lot of misinformation out there which is being promoted by opponents to fracking. They contend that fracking causes water contamination. Although it is true that on rare occasions, some companies haven’t followed protocol, and there has been some contamination of ground water. Regulations are stiff and drilling companies have to follow strict guidelines when drilling any well, let alone a fracking well. Each well is inspected at each step along the way to assure they are being safely drilled.This model was constructed by ConocoPhilips Company. It depitcs hydraulic fracking better than any other I have found.
The Fracking Process
One thing to note, is that shale gas lies thousands of feet below any water supply. Most water tables are within a few hundred feet of the Earth’s surface, while shale natural gas lies typically 4,000 to 10,000 feet down. As with any gas or oil well, a well is first drilled some distance beyond the water level. Before proceeding with deeper drilling, multiple barriers of steel casings and cement are installed far below the water level. It extends at least 50 feet below the lowest water level. This is installed to protect the fresh water throughout the drilling process and the life of the well.
Once the fresh water barrier is in place, drilling continues vertically thousands of feet to the kickoff point. Once the well is at the level of the shale reservoir, the curved and horizontal sections are drilled laterally for thousands of feet into the targeted formation.
At this point, steel casing and cement are placed all along the remainder of the well. Now, an electrical current is sent through wires to a perforating (perf) gun. This gun shoots small holes through the horizontal casing, cement, and a short distance into the shale rock itself.
At this point, horizontal drilling is combined with fracking. Pressurized water along with sand and certain chemicals are forced through the holes into the fissures that were created by the perf gun. This pressurized water causes more fracturing of the shale rock. The sand holds these fractures open, which allows the gas to escape. The gas, which is pressurized, flows through the cracks into the well bore and up to the surface.
Of the mixture used for the fracking process, 90% is water, while about 9.5% is sand. The remaining .5% is
Click here for an interactive image that Penn State Public Broadcasting has put together that explains the overall hydraulic fracturing process. Water accounts for about 90 percent of the fracturing mixture and sand accounts for about 9.5 percent. Chemicals account for the remaining one half of one percent of the mixture.
Where does the water come from that is used in fracking?
Depending on where the well is being drilled, the water is gathered from rivers, creeks, and lakes. What doesn’t come from those sources is either purchased from municipalities. Water is often transported to the drill site by truck. At times, temporary pipelines are installed underground. As for Marcellus Shale, 65% of the water is surface water.
How much water is used during the fracking process?
Each drill site requires between 3 and 5 million gallons of water per frack.
What chemicals are added to the water and why?
More than fifty different chemicals are added to the water for the fracking process. The purpose of the chemicals is to prevent the growth of microorganisms, to maintain a proper fluid viscosity, and to prevent the metal pipes from corrosion.
There are more than 50 known chemicals that may be added to the water that is used for hydraulic fracturing. These chemicals generally represent less than 1% of the total composition of the fracking fluid. Such chemicals avert microorganism growth, prevent corrosion of metal pipes, and maintain fluid viscosity. There are also additives that create slack water. This reduce friction, allowing the fracking fluids to penetrate at a higher rate with a lower pressure.
What happens to the water once it has been used for fracking?
Only about 10% to 30% of the total water that is used during the fracking process gets back to the surface. The remainder of the water stays deep below the ground. Much of it is absorbed by the shale formation. The water that does return to the surface is called flowback. This flowback is managed and disposed of in one of three ways: It is injected into permitted disposal wells, delivered to a water treatment facility or recycled (used for another well).
When drilling companies get a drilling permit, they must identify how the wastewater will be treated and stored. They must abide by the local guidelines for the disposal of water. As to the Pennsylvania Department of Environmental Protection (DEP), the waste water must be treated to have a total dissolved solids (TDS) concentration of 500 parts per million or less. This is consistent with the drinking water standards for Pennsylvania.
Major Shale Formations
There are many shale formations across the United States. This map is provided by the Energy Information Association (EIA) and lists all of the major shale formations in the lower 48 states as of May of 2011. In this article, five of the largest shale gas deposits will be discussed: Eagle Ford Shale, Bakken Shale, Barnett Shale, Haynesville Shale, and Marcellus Shale. You can find each of them on the map. As you can see, the largest deposit of all is the Marcellus Shale
Eagle Ford Shale
Eagle Ford Shale is located in the southern tip of Texas. The shale formations vary in depth from 4,000 to 14,000 feet. It gets its name from the town Eagle Ford, Texas. There are also a lot of liquids across much of the play. There is also development of ethane, propane, and butane, which command better prices than natural gas.
Eagle Ford Shale (EFS) Companies
In 2002, Lewis Energy is reported to be the company that drilled the first EFS targeted well. The first high producing Eagle Ford Shale well was drilled by Petrohawk Energy in 2008. This well had 10 frac stages along a 3,200 foot lateral area, and produced 7.6 million cubic feet of gas per day.
For additional information on Eagle Ford Shale check out their website.
The Bakken Shale is located in North Dakota, Montana, and Saskatchewan, and parts of Manitoba Canada. This shale is very rich in oil content. It is estimated that Bakken Shale contains a little less than 2 trillion cubic feet of natural gas.
For additional information on Bakken Shale check out their website.
This formation covers about 5,000 square miles, and stretches from the west and south of Dallas, Texas. It is named after John W. Barnett who settled in the San Saba County during the late 19th century. Actually a local stream was named after him. When the black organic-rich shale was noted by geologists, they named it after Barnett Shale. Significant drilling didn’t take place until the late 1990’s. Devon Energy acquired Mitchell Energy, a small independent company in 2002. They have established themselves as the leading producer from the Barnett Shale. This happened through the new advances in horizontal drilling and well fracking. Other major players such as Exxon are starting to be attracted to the Barnett Shale.
For more information on the Barnett Shale, check out this website.
The Haynesville Shale formation is located in eastern Texas, northwestern Louisiana, and southwestern Arkansas. It extends to a depth of 10,500 to 13,000 feet and is part of a large rock formation known to geologists as the Haynesville Formation. The Haynesville Shale covers an area about 9,000 square miles and is at an average, about 200 to 300 feet thick. It contains vast quantities of recoverable natural gas. This was known prior to 2008, but at that time it wasn’t economically feasible to try to extract natural gas. Due to rising prices and the advancement of hydraulic fracking, it has become an economically wise decision to extract the natural gas.
The Haynesville Shale gets its name from the town of Haynesville, Louisiana. At one time, it was part of the Bossier Shale, but is now classified as a separate formation.
For more information on Haynesville Shale, check out this website.
The Marcellus Shale is black organic rich shale that is found beneath much of Pennsylvania, West Virginia, Ohio, and New York. There are also small areas of Virginia, Kentucky, Tennessee, and Maryland that contain Marcellus Shale. You can see how large this formation is from the map below.
It was estimated in 2008 that the Marcellus may contain more than 500 trillion cubic feet of natural gas, and that 10% of it should be recoverable. Terry Englander, a geoscience professor at Penn State University said that that amount of natural gas is enough to supply the entire nation for about two years and has a value of close to one trillion dollars.
For more information on Marcellus Shale, check out this website.
Rising Objections to the Fracking Process
As natural gas production has stepped up, and the technology of hydraulic
fracking has increased, there has been a lot of concern raised by
environmentalists. The primary concern is that the practice of fracking
is contaminating our ground water. There are utube videos of people using a
lighter to light a flame from their faucet water. They are attributing
this to fracking contamination. Lisa Jackson, EPA Administrator
testified that there is no evidence that fracking had caused any
groundwater contamination, although there are ongoing investigations
being conducted. Before you make up your mind on the fracking process,
you need to check out the facts. View the video below which I believe
will be informative. It takes several of the arguments from a Gasland
Documentary that argues against natural gas fracking and gives the real
facts about what is presented.
As natural gas production has stepped up, and the technology of hydraulic fracking has increased, there has been a lot of concern raised by environmentalists. The primary concern is that the practice of fracking is contaminating our ground water. There are utube videos of people using a lighter to light a flame from their faucet water. They are attributing this to fracking contamination. Lisa Jackson, EPA Administrator testified that there is no evidence that fracking had caused any groundwater contamination, although there are ongoing investigations being conducted. Before you make up your mind on the fracking process, you need to check out the facts. View the video below which I believe will be informative. It takes several of the arguments from a Gasland Documentary that argues against natural gas fracking and gives the real facts about what is presented.
If you're interested in getting more detailed information on the
process of fracking, and the precautians taken by the drilling
here to view several other videos. These videos will give a better
insight into the entire process of extracting natural gas. In the video
below, Nick Gillespie with Reason TV conducts an interview with
concerning the safety of the practice of hydraulic fracturing.
If you're interested in getting more detailed information on the process of fracking, and the precautians taken by the drilling companies, click here to view several other videos. These videos will give a better insight into the entire process of extracting natural gas. In the video below, Nick Gillespie with Reason TV conducts an interview with Ronald Bailey concerning the safety of the practice of hydraulic fracturing.This is a very informative video.
Ensuring Fracking and Natural Gas Production is Safe
The practice of fracking has been used for over 60 years. There are more than a million wells drilled each year where fracking is used. Safeguards have been put into place to guard against any negative environmental impact. When it comes to ground water, fracking wells are no different than any other oil or gas well that is drilled. The same technique is used for all. That doesn’t mean that companies can’t cut corners and produce an unsafe well.
There is one primary method used to prevent groundwater contamination. This method consists of drilling well beyond the groundwater supply, and immediately installing a steel pipe, which is called a casing. This pipe is then cemented into place. This steel casing extends approximately 50 feet below any existing water supply to insure no contamination can escape form the well into the water supply. This casing in conjunction with other steel casing and cement sheaths are used to assure groundwater is protected for the life of the well.
There are many federal and state laws and regulations in place to ensure all operations are conducted in an environmentally responsible way. All state drilling regulations address groundwater protection. The rock formations that lie between the natural gas supply and water table offer thousands of feet of protection against any seepage from the well site to the water supply. Dr. Charles Grout from the University of Texas stated, "Drilling for natural gas in itself doesn't pose a threat to air and water quality, if it‘s done properly." Hydraulic Fracking is a safe process when followed according to strict guidelines. As a result of it, we can gain energy independence which equates to a stronger national security.