PITTSBURGH (AP) -- New research on Marcellus Shale gas drilling in Pennsylvania may only add to the debate over whether the industry poses long-term threats to drinking water.
A paper published on Monday by Duke University researchers found that gas drilling in northeastern Pennsylvania did not contaminate nearby drinking water wells with salty brinewater, which is a byproduct of the drilling.
But the researchers say that deep naturally-occurring pathways can bring the brine up into shallow aquifers, and that could potentially bring drilling fluids to the surface in some areas.
Environmentalists have claimed that gas drilling can pollute drinking water aquifers. The industry and many state and federal officials say the practice is safe when done properly, but there have been cases where faulty wells caused pollution.
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