Are Fracking Wastewater Wells Poisoning the Ground beneath Our Feet? Leaking injection wells may pose a risk–and the science has not kept pace with the growing glut of wastewater

Are Fracking Wastewater Wells Poisoning the Ground beneath Our Feet? Leaking injection wells may pose a risk–and the science has not kept pace with the growing glut of wastewater by Abrahm Lustgarten and Propublica, June 21, 2012, Scientific American
But until recently, scientists and environmental officials have assumed that deep layers of rock beneath the earth would safely entomb the waste for millennia. There are growing signs they were mistaken. … Damage to the cement or steel casing can allow fluids to seep into the earth, where they could migrate into water supplies. Regulators say redundant layers of protection usually prevent waste from getting that far, but EPA data shows that in the three years analyzed by ProPublica, more than 7,500 well test failures involved what federal water protection regulations describe as “fluid migration” and “significant leaks.” … And not every well can be repaired. … Another way wells can leak is if waste is injected with such force that it accidentally shatters the rock meant to contain it. A report published by scientists at the Department of Energy’s Pacific Northwest National Laboratory and the University of Texas said that high pressure is “the driving force” that can help connect deep geologic layers with shallower ones, allowing fluid to seep through the earth. … A year later, a corroded hazardous waste well for pulping liquor at the Hammermill Paper Co., in Erie, Pa., ruptured. Five miles away, according to an EPA report, “a noxious black liquid seeped from an abandoned gas well” in Presque Isle State Park. … In 1989, the GAO reported 23 more cases in seven states where oil and gas injection wells had failed and polluted aquifers. … The GAO concluded that most of the contaminated aquifers could not be reclaimed because fixing the damage was “too costly” or “technically infeasible.” … Ultimately, the energy industry won a critical change in the federal government’s legal definition of waste: Since 1988, all material resulting from the oil and gas drilling process is considered non-hazardous, regardless of its content or toxicity. … Conventional wisdom says fluids injected underground should spread at a rate of several inches or less each year, and go only as far as they are pushed by the pressure inside the well. In some instances, however, fluids have traveled faster and farther than researchers thought possible. In a 2000 case that wasn’t caused by injection but brought important lessons about how fluids could move underground, hydrogeologists concluded that bacteria-polluted water migrated horizontally underground for several thousand feet in just 26 hours, contaminating a drinking water well in Walkerton, Ontario, and sickening thousands of residents. The fluids traveled 80 times as fast as the standard software model predicted was possible.