The process of high-volume horizontal hydraulic fracturing, or “hydrofracking,” was first used commercially by Halliburton in 1949. It involves injecting millions of gallons of water, mixed with sand and chemicals, deep into the ground at high pressure in order to break up dense shale rock formations and release trapped natural gas to the surface.  The risks associated with hydrofracking, however, are numerous and diverse, affecting every stage of the process from transporting and drilling to waste storage and disposal. 

A hydrofracking well exploded near Leroy Township, Pennsylvania on Tuesday, spilling chemically treated water into a nearby creek that feeds the Susquehanna River and prompting the evacuation of certain residents.  The incident occurred while a crew from Chesapeake Energy Corporation was in the midst of “fracking” the well, a method by which one injects a mixture of water, sand and chemicals into dense rock at high pressures in order to release oil and gas.  The cause of the spill was reportedly due to equipment failure.