Hydraulic fracturing technology was first developed and commercialized in the late 1940s. Since then over 1.2 million oil and natural gas wells have been hydraulically fractured. During the completions, or hydraulic fracturing stage of development, operators pump, water, mixed with propping agent (usually playground sand), and a handful of additives to control physical characteristics, such as viscosity, pH, surface tension, and scale prevention, at high pressure down the wellbore through the well casing. The pressure creates fractures in the rock formation; the propping agent (sand) holds the fractures open to allow the gas to flow through the opened porous formation once the well has been completed.
To be sure, the industry continues to invest in research and development to find new and innovative ways to gain better efficiencies and further reduce its environmental footprint. An example of this research was developed and widely deployed right here in Pennsylvania. Just a few short years ago, companies began investing in water treatment technologies to recycle and reuse water to fracture wells. Today, thanks to this innovation, according to Pa. DEP data, Marcellus Shale producers are recycling upwards of 85 percent of all water that returns to the surface. The remaining 15 percent is safely disposed of in EPA-regulated underground injection wells.