This story is published in partnership with DeSmog , the climate investigations site.  A cache of government documents dating back nearly a century casts serious doubt on the safety of the oil and gas industry’s most common method for disposing of its annual trillion gallons of toxic wastewater: injecting it deep underground.  Despite knowing by the early 1970s that injection wells were at best a makeshift solution, the U.S. Environmental Protection Agency (EPA) never followed its own