New studies are showing the drinking water around natural gas fracking sites in Pennsylvania is in pretty good shape.

A study published in the journal Proceedings of the National Academy of Sciences found methane spikes were due to natural variability, not drilling.

Some older reports had indicated that problems of contamination found in drinking water, like heavy metals and drilling materials, were linked to faulty gas wells and not to the actual drilling process.

Another study by Penn State University used information from the Pennsylvania Department of Environmental Protection and found water quality either unchanged or improved when measuring barium arsenic and iron.

The Associated Press reports Carnegie Mellon University engineering professor, Allen Robinson, who was not involved in the Penn State study questioned whether results could be skewed by the examination focused on just Bradford County in the Northern Tier.  Robinson told AP by email that the data overall demonstrates there is not a ground water contamination crisis and that is “good news.”

The Marcellus Shale Coalition issued a statement saying the studies “reflect our industry’s deep commitment to environmental and groundwater protection.”

Pennsylvania is the nation’s #2 gas producing state behind Texas thanks to the drilling of over 11,000 wells since the start of gas exploration and development of the Marcellus Shale Play in 2008.