The Pennsylvania Department of Environmental Protection received on Saturday, May 19th a new complaint of possible gas migrating to private water wells and is investigating to determine the source of the gas.
According to press reports, the complaint of gas is about 2 water wells in Leroy Township, Bradford County. Gas has been vented from those wells. www.stargazette.com/apps/pbcs.dll/article?AID=2012205210332.
To be clear, this investigation appears to be about methane migration and not about hydraulic fracturing fluids returning from depth to pollute water.
It would be surprising if pre-drill water testing was not done at the two water wells that now are the focus of the examination. Assuming that such pre-drill testing was done, those pre-drill test results will help to determine the source of gas in the water. Isotopic testing of the gas will also be likely needed.