Fred Baldassare who is a nationally recognized expert on gas migration and formerly employed by the Pennsylvania Department of Environmental Protection has published here a must read comment concerning the source of the gas that migrated due to drilling problems in the Dimock area of Susquehanna county.
See Fred's comment to the monday, May 9th posting about the Duke University gas migration study.
Fred did the testing of the gas in the 19 water wells around Dimock that DEP found had been contaminated with methane as a result of gas drilling. But what was the source of the gas? Was it Marcellus gas that was the target of the drilling that migrated?
Fred confirms that the gas in the 19 water wells around Dimock was not naturally occurring (biogenic gas) and that it was not Marcellus gas. Instead the gas was shallower gas that was encountered in the drilling operation as drilled to get to the Marcellus gas. To be clear the gas did migrate due to drilling.
The Duke study, however, was not clear about the precise source of the gas that did migrate. Again please read Fred's comment.