By IAN URBINAAugust 3, 2011
For decades, oil and gas industry executives as well as regulators have maintained that a drilling technique known as hydraulic fracturing, or fracking, that is used for most natural gas wells has never contaminated underground drinking water.
Rex W. Tillerson, the chief executive of ExxonMobil, has said that there are no reported cases of a freshwater aquifer having ever been contaminated from hydraulic fracturing.
The claim is based in part on a simple fact: fracking, in which water and toxic chemicals are injected at high pressure into the ground to break up rocks and release the gas trapped there, occurs thousands of feet below drinking-water aquifers. Because of that distance, the drilling chemicals pose no risk, industry officials have argued.
“There have been over a million wells hydraulically fractured in the history of the industry, and there is not one, not one, reported case of a freshwater aquifer having ever been contaminated from hydraulic fracturing. Not one,” Rex W. Tillerson, the chief executive of ExxonMobil, said last year at a Congressional hearing on drilling....continued...
