For the first time, scientists have discovered chemicals used in a controversial natural gas drilling technique in water wells near the gas sites.
Scientists for the Environmental Protection Agency (EPA), testing wells near a major gas drilling area in Wyoming, have found traces of drilling chemicals in three wells, and other contaminants — including oil, gas, and heavy metals — in 11 of 39 wells recently tested, according to the Web site Pro Publica.
The chemicals are used in a process called hydraulic fracturing, in which drilling fluids and sand are injected under high pressure to break up rock and release gas.