(This is part XII and the final part of this series on energy. We hope it helped the reader better understand the issues facing our country and our state as we endeavor to tackle the problem of providing our citizens and our businesses with their energy needs.)
* Some natural gas and oil resources are located in semi-porous or non-porous rocks that don’t allow the fuel to freely flow when accessed through drilling. Such fuels are often found in shale formations and are referred to as “tight oil” and “tight gas.” These resources can be extracted by using a combination of technologies known as horizontal drilling and hydraulic fracturing.
* Horizontal drilling involves penetrating the ground vertically (like traditional drilling) and then turning horizontally in order to drill along the layer that contains the fossil fuel resources. This method of drilling exposes more of the fossil fuel resources to the bore of each well, thus increasing yields and decreasing the surface footprint of drilling operations.
* Horizontal drilling was first successfully employed in 1929 and has been used commercially since the late 1980’s. By 1990, more than 1,000 horizontal wells were drilled worldwide, almost all for the purpose of extracting crude oil.
* Hydraulic fracturing or fracking involves injecting fluids at high pressures from the bore of a well into the layer that contains the fossil fuel resources. This process creates fractures in the rock, which allows the fuels to flow to the bore of the well. The fluids used for fracking typically contain sand or ceramic beads that serve to hold open the fractures after they have been created. This fluid also contains varying chemicals that are used for purposes such as preventing pipe corrosion. (A detailed description of the process is shown in the video below.)
* Hydraulic fracturing was first successfully employed to drill for oil in 1947 and has been used commercially since the 1950’s. By 1955, more than 100,000 fracking treatments were performed. In the 1980’s and early 1990’s, Texas oilman George Mitchell refined the process of fracking to extract natural gas from shale in a cost-effective manner.
* In the early 2000’s, horizontal drilling coupled with hydraulic fracturing became widely used to extract tight gas. In the mid-2000’s, the combination of these technologies also became widely used to extract tight oil. The process for extracting natural gas is shown in this video:
* From 2005 to 2015, U.S. natural gas production increased by 50%, primarily due to the use of horizontal drilling coupled with hydraulic fracturing in shale formations.
* In 2016, the U.S. Energy Information Administration reported that fracking:
- has “allowed the United States to increase its oil production faster than at any time in its history.”
- now produces “about half of total U.S. crude oil production.”
* Per a 2012 U.S. Government Accountability Office (GAO) report:
* The primary concern about fracking is that the fuels it releases from tight formations will migrate to the surface of the earth and contaminate wells and other bodies of water.
* In areas that are rich in petroleum and natural gas (methane), these fuels commonly seep up to ground level through natural processes:
- Per the Institute for Plasma Physics in the Netherlands: “In 1859, the first petroleum was pumped out of the ground in Pennsylvania in the USA. For long the petroleum had been a nuisance, contaminating wells for drinking water.”
- Per the U.S. Geological Survey: “Reports from the 1800’s document [methane] gas bubbles in water wells, in streams, and in fields after heavy rains; this evidence suggests that migration has always existed.”
- Per a 2007 academic textbook The Chemistry and Technology of Petroleum: “Most of the crude oil currently recovered is produced from underground reservoirs. However, surface seepage of crude oil and natural gas are common in many regions.”
- Per the Encyclopædia Britannica: “The first discoveries of natural gas seeps were made in Iran between 6000 and 2000 BC. Many early writers described the natural petroleum seeps in the Middle East, especially in the Baku region of what is now Azerbaijan.”
- Per the Kentucky Department for Environmental Protection: “Water wells located in pump houses, well pits, basements or any enclosed structure should be properly vented as a safety precaution to prevent the buildup of methane. … Naturally occurring gases, such as methane and hydrogen sulfide, may be present in some wells. These gases occur naturally in the subsurface, accumulating in voids within the rock and as dissolved gas in groundwater.”
- Per GAO: “Methane can occur naturally in shallow bedrock and unconsolidated sediments and has been known to naturally seep to the surface and contaminate water supplies, including water wells.”
* Because methane is odorless, invisible, and generally nontoxic, people who have naturally occurring methane in their wells may be unaware of it until they test for it.
* Fracking is typically performed at depths of 6,000 to 10,000 feet, and the fractures can extend for several hundred feet. Drinking water is commonly located at depths of less than 1,000 feet.
* As with conventional drilling and other industrial processes (including biofuel production), in cases of accidents and negligence, fracking can and has caused gas leaks, contaminant spills, and other environmental damage.
* In May of 2011, Lisa Jackson, head of the Obama administration EPA stated: “I’m not aware of any proven case where the fracking process itself affected water, although there are investigations ongoing.”
* A 2012 GAO evaluation of three major studies and a series of interviews with regulatory officials in eight states found no proven cases where groundwater contamination was caused by properly conducted fracking. However, GAO noted that:
* In 2014, the U.S. Department of Energy published the results of an investigation to determine if natural gas or fracking fluids had migrated upward to an underground gas field that is “1,300 feet below the deepest known groundwater aquifer” at six fracking wells in Greene County, Pennsylvania. The study found there was “no detectable migration of gas or aqueous fluids” to the gas field.
Email this author