For one thing, it's possible that some people will not be diagnosed with cancer until years down the road, creating challenges for determining whether the cancer originated because of work at ground zero.

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In fact both the EPA and the Ground Water Protection Council, a nonprofit made up of state regulatory agencies, have published studies determining that no documented evidence of fracking-sourced groundwater pollution has been found.

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And while the Energy Policy Act of 2005 prevents the EPA from explicitly regulating fracking wells under the Safe Drinking Water Act, both the EPA and the Ground Water Protection Council, a nonprofit made up of state regulatory agencies, have published studies determining that no documented evidence of fracking-sourced groundwater pollution has been found.

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