|What Is Hydraulic Fracturing and What It Is Used For
Hydraulic fracturing or a frac job is the process of using water and sand, along with a small amount other chemicals forced at extremely high pressure from the surface, down a newly drilled and cased oil or gas well. Using a system of multiple high pressure pumps, tanks and lines, the frac fluid is forced into the rock formation where oil or natural gas is present. The force of the fluid opens up tiny cracks and fissures between the grains of the rock and expands upon the natural permeability of the reservoir. Permeability is simply how well a fluid or gas (such as oil or natural gas) can travel through the rock. Forcing high pressure fluid opens up more channels for the oil or natural gas to flow out of. Hydraulic fracturing is often done in stages, with different pressures and fluid additives used at each stage. Below is a video of the process of fracking a well.
One additive that is used to keep the fissures open are tiny spherical frac beads. Frac beads that are used are made of several substances, including glass, polystyrene, and ceramic material. These tiny round beads, similar in size to a grain of sand, help hold the fractured rock open permanently. This type of additive is known as a proppant. Sand can also be used as a proppant in a hydraulically fractured well.
Environmental Concerns About Hydraulic Fracturing
A frac job done in a shale formation, such as the Eagle Ford shale, involves as much as six million gallons or more of water that is pumped down the newly drilled oil or gas well. The fact that valuable surface or groundwater water is used, and the fact that some chemicals are added to hydraulic fracturing fluid has caused concern from many environmental groups in areas where shale oil and gas drilling is occurring. It should be noted that there are very strict EPA and state regulations concerning water use and disposal and that natural gas drilling uses much less surface water and produces less waste than coal mining. Hydraulic fracturing has been used in horizontal and vertical oil and gas wells for over sixty years, and as was stated in hearings recently in Washington, has not resulted in a single case of groundwater contamination. There has however, been a handful of cases of groundwater contamination from an unrelated procedure known as water injection, as used in secondary recovery of oil and gas from old wells.
Hydraulic fracturing has been done successfully for years in states such as Texas, where it is heavily regulated by the Texas Railroad Commission. Smaller states, such as West Virginia have had to scramble to create agencies to monitor the oil and gas industry, which is relatively new to their states. As these states develop the same intense regulatory structures needed to regulate procedures such as hydraulic fracturing then possibly many public concerns about safety of the procedure will diminish. Many states have enacted legislation which requires oil and gas companies to disclose all chemicals used in frac jobs. Recently Texas passed House Bill 3328, which requires a full disclosure of all chemicals used.
Not The Same Thing.
Enhanced oil recovery or secondary recovery, using water injection, is the process of using high pressure water, pumped through injection wells into oil reservoirs and shallow coal beds, or into seams of shallow uranium bearing sand to increase production from existing wells. Water injection has caused some wells to be contaminated in isolated cases. These are most often the cases that environment groups point to, and show videos of, featuring colored tap water coming from rural home faucets. It is very important to realize that this is not caused by hydraulic fracturing. Hydraulic fracturing and Secondary Recovery are not the same thing.
Environmentalists have pointed to several potentially dangerous chemicals such as benzene, toluene, naphthalene, trimethylnapthalene, ethylbenzene and xylene that have been used in hydraulic fracturing according to EPA records. It should be noted that most of these chemicals are not used presently in frac jobs in the Marcellus shale. One reason is because it is often cheaper and requires less paperwork and oversight to use more benign products that work just as well. There is a lot of misinformation out there. Chesapeake's Hydraulic Fracturing Facts has done an excellent job of explaining the hydraulic fracturing process on their website. None of the chemicals most often cited by some groups opposed to the process are used in Marcellus shale wells by Chesapeake Energy, the largest operator in the area.
Water and sand make up 99.5% of the frac fluid. The other one half of one percent of hydraulic fracturing fluid contains chemicals that are used in everyday products such as cosmetics and swimming pool cleaners. As much as six million gallons or more of water may be used from start to finish, drilling and completing an horizontal oil or gas well.
List of Hydraulic Fracturing Ingredients that Make up .5 percent Of Fluid
Most of these chemicals remain locked in the reservoir permanently. Somewhere of around 40% or more of frac water is returned to the surface as "produced water". This water may contain high levels of chlorides and other pollutants which prevent it from being released into the environment. Produced water, which is recovered during flowback must be treated and purified before returning it to the environment or being pumped down an approved deep disposal well. A number of companies have developed treatment processes which can return produced water to municipal water quality standards, after which it is either re-used to frac new wells or released into streams. This process is being widely adopted in shale plays such as the Marcellus, where the geology is not favorable for deep injection wells.
Safe Distance Between Where Hydraulic Fracturing Is Done And Water Aquifers
Frac jobs, such as in the Marcellus shale are done at depths of over 8000 feet, far below water aquifers. If you can imagine a vertical distance of a mile and a half, and then picture water bearing zones in the first few hundred to one thousand feet (see illustration above) you can get an idea of the separation distance. Many layers of solid rock, lie between and because of this no groundwater contamination is possible. What needs to also be realized is that the gas and oil bearing rock stratas being hydraulically fractured already contain dozens of petroleum based chemicals that have been formed as a result of heat and pressure. Xylene is naturally present in oil and gas reservoirs in small quantities and because of the vertical distance involved between the reservoir and the groundwater aquifer, no contamination has occurred over millions of years, despite geologic events occurring over millenniums.
Where Hydraulic Fracturing Is Used
This technique is more than 60 years old, and has made possible the production of seven billion barrels of domestically produced oil and over six hundred trillion cubic feet of natural gas so far. The National Petroleum Council reports that as many as eighty percent of new oil and gas wells will by hydraulically fractured. Frac jobs, along with Horizontal Drilling are the main method that is being used to produce shale gas and oil from the Marcellus, Eagle Ford, Haynesville, Bakken and Barnett shales.
Thoughts On Regulation Of Hydraulic Fracturing
It is important for those who are concerned about the use of hydraulic fracturing to know the facts. There has not been a single case of groundwater contamination attributed to a hydraulic frac job in the sixty plus years it has been done. During that time state agencies that regulate oil and gas drilling have done a great job of enforcing the rules regarding frac jobs. Without hydraulic fracturing, production of domestic natural gas from shale reservoirs would decline dramatically causing an increased reliance on imported oil.
A Cost and A Risk To Every Form Of Energy
When it comes to oil and gas drilling in many parts of the United States the "not in my backyard" mentality prevails. While there will always be places that are off limits to exploration, we must consider the cost of the energy that we rely on. Even if you drive a Prius, you are still using fuel which came from oil and gas wells. The food you had for dinner was most likely fertilized by products that were made from natural gas. If the oil that runs our cars, trucks, busses, factories and grows our food comes from another part of the world, there is often a security risk as well as a huge financial cost to our country. So, do we tolerate and manage the risks of getting oil and gas from within our borders, or do we continue to rely on dictators and fundamentalist regimes around the world who often hate us? Again, every form of energy has a cost. If you turn on a blender to make a smoothie, you have either used some natural gas, oil, coal, nuclear energy, or helped cause another wind turbine to be built somewhere, which might kill a migratory bird or two. Even solar energy, if fully taken advantage of would require covering thousands of acres of U.S. desert, home to creatures such as the desert tortoise. Our energy needs must be filled somehow and for the time being, oil and gas must be a part of the equation. One engineer is reported to have calculated that to entirely replace oil and gas we would have to build a wind turbine every minute for the next twenty years. That's a lot of wind turbines to be made, using fiberglass, steel and aluminum, all of which ironically are manufactured using oil, gas and coal. We simply can't transition to 100% renewable energy without using fossil fuels to get us there. The more of these fuels that we can get right here in the U.S., the safer we are as a nation. As ex oil man T. Boone Pickens has stated it is the "largest voluntary transfer of wealth in world history", speaking of the money that we send overseas for energy. This huge drain on our economy must stop the only way for that to happen is that we have to accept and manage the risks of drilling for domestic oil and gas.
The United States is the Saudi Arabia of natural gas. Natural gas is a cleaner burning fuel that produces much less particulate matter and CO2 than burning oil does. It is our most abundant energy resource, and a far better one than coal, to help us transition to a 100% renewable energy economy. The U.S. has at least a one hundred year supply of natural gas, as well as major reserves of crude oil locked in shale formations across the U.S. We cannot afford to stop natural gas drilling in areas such as the Marcellus shale based on unscientific and emotionally driven legislation. It is important that hydraulic fracturing be discussed rationally, based on facts, before over - regulation makes shale gas drilling unprofitable, or even unfeasible. Recently the sixth largest discovery of oil in U.S. history was made on land, south of San Antonio, Texas in the Eagle Ford Shale To produce any of this oil requires horizontal drilling and hydraulic fracturing.