Texas' oil and gas regulator says an investigation into explosive gas tainting a Dallas-area water supply has found no evidence the contamination originates with gas drilling activity nearby.
The Railroad Commission report, released on Wednesday, says the methane levels have increased in many of the water wells tested in September 2013 compared to what was measured in 2010. But the agency says it cannot definitively link the gas found in the wells to hydraulic fracturing operations in the Barnett shale.
Some independent scientists who have tested the gas in the wells have said a fingerprint-like analysis of the methane links it to gases being produced from the Barnett shale. The U.S. Environmental Protection Agency had made a similar finding when it first investigated, but later rolled back.
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