On August 3, The New York Times published an article that begins:
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.
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.
It is a refrain that not only drilling proponents, but also state and federal lawmakers, even past and present Environmental Protection Agency directors, have repeated often.
But there is in fact a documented case, and the E.P.A. report that discussed it suggests there may be more. Researchers, however, were unable to investigate many suspected cases because their details were sealed from the public when energy companies settled lawsuits with landowners.