Hydraulic fracturing (also known as hydraulic stimulation) is the process of creating fissures, or fractures, in underground formations to stimulate well production. Natural gas and oil well completions using hydraulic fracturing technology have been conducted by the industry since the late 1940s, and the technique has become a key component of the natural gas and oil production process worldwide. Regardless of whether they are vertical or horizontal wells, this process is used in nearly all natural gas and oil wells drilled in the U.S. today, including more than 99% of the 12,200 wells Chesapeake has drilled since our founding in 1989. Modern hydraulic fracturing is a highly engineered, controlled, sophisticated and safe procedure.

Hydraulic fracturing occurs in underground formations thousands of feet below the surface and any freshwater zones. It involves the use of high pressure truck-mounted pumps to pump water, sand and a small amount of chemical additives into the formation source rock to create fractures. The newly created fractures are “propped” open by the sand, which allows the natural gas or oil to flow into the wellbore and be collected at the surface. Variables such as rock formation and thickness of the targeted formation are studied by scientists before hydraulic fracturing is conducted. The result is a highly sophisticated process that optimizes the network of fractures.

When conducted properly, the process is contained entirely within the steel casing, cemented wellbore and the natural gas- and/or oil-bearing formation. The hydraulic fracturing process typically occurs over 7 to 17 days in multiple stages. The activity is conducted at the onset of the producing life of the well, which can be 50 years or more.​​​​​​