How Natural Gas is Extracted
Many people mistakenly think that natural gas is found in pockets or caverns deep underground. But the truth is, natural gas from the Marcellus Shale is trapped inside the deep shale formation itself. Releasing the gas is like pulling water out of a block of concrete. Sound impossible? For a long time, it was. It took decades of research before companies proved how to successfully extract natural gas from shale formations. This research and development effort began in Fort Worth, Texas in 1982 and has since been successfully implemented across the United States for more than a decade. The tools and technology we utilize have actually been in practice for more than half a century.
Drilling is like paving a road to the target formation where natural gas is located. Simply drilling through the Marcellus Shale doesn't produce natural gas. In order to extract the natural gas and keep it flowing for years, we have to take an extra step called hydraulic fracturing, or "fracking". This proven and tested technology has been used in the United States more than a million times.
Since water can't be compressed, if you put enough pressure behind it, it can fracture just about anything. In this case, water is used to create fractures in the shale that are about the width of a sheet of paper and are held open by sand. This allows the natural gas to be released from the formation and flow freely.
The water we use in hydraulic fracturing comes from a local water company or is obtained from a nearby water source, such as a stream, pond, lake or river. All aspects of our water usage are reviewed, approved and inspected by state regulators. While this process involves roughly 99.9% water and sand, it also requires about four highly diluted and common chemicals. These additives are carefully managed, safely handled and are encountered by most of us in our everyday life.
Hydraulic fracturing typically lasts a week or two. Before, during or after the wells are completed, we install a pipeline and other equipment to monitor and measure the flow of natural gas and move it safely to our homes, businesses and power plants.