Texas state regulators report that a second investigation has again shown insufficient evidence that oil and gas development activities, including hydraulic fracturing, have caused methane pollution in nearby private water wells. The commission looked at records on nine private wells in the Silverado area of Parker County, as well as regulatory documents and other public data since 2011 when complaints spurred their first investigation. The regulators say:
The occurrence of natural gas in the complainants’ water wells may be attributed to natural migration of gas from the shallow Strawn Formation, exacerbated by water well construction practices whereby some water wells have penetrated ‘red beds’ in the transition interval between the aquifer and the Strawn Formation. Contribution of natural gas to the aquifer by the nearby Barnet Shale gas production wells is not indicated by the physical evidence.