Scientists have theorized that impermeable layers of rock would keep the fluid, which contains benzene and other dangerous chemicals, safely locked nearly a mile below water supplies.
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But the study, using computer modeling, concluded that natural faults and fractures in the Marcellus, exacerbated by the effects of fracking itself, could allow chemicals to reach the surface in as little as 'just a few years.'
'Simply put, [the rock layers] are not impermeable,' said the study's author, Tom Myers, an independent hydrogeologist whose clients include the federal government and environmental groups. (Source)
Radiation isn’t released into the environment only via nuclear plants and bombs. Geologist Tracy Bank found that fracking mobilizes rock-bound uranium, posing a further radiation risk to our groundwater. She presented her findings at the American Geological Society meeting in Denver last November. (Source)
The fracking fluid contains chemicals that would be illegal to use in warfare under the rules of the Geneva Convention.