New research into hydraulic fracturing's impact on drinking water indicates methane found in some Pennsylvania drinking water was not related to the fracking. According to an AP news report, Pennsylvania has documented 243 cases of private water supply contamination related to oil and gas activities since 2008.

The new findings are similar to a study published last year (also highlighted in the AP report), and both differ significantly from earlier research. Do any of the results really tell the whole picture?

According to an article from the American Association for the Advancement of Science:

The new study of 11,309 drinking water wells in northeastern Pennsylvania concludes that background levels of methane in the water are unrelated to the location of hundreds of oil and gas wells that tap hydraulically fractured, or fracked, rock formations. The finding suggests that fracking operations are not significantly contributing to the leakage of methane from deep rock formations, where oil and gas are extracted, up to the shallower aquifers where well water is drawn.

Professor Donald Siegel, Department of Earth Sciences, Syracuse University, led the study, published this month in Environmental Science & Technology.

Scientists reached similar conclusions in a study published in 2014. AP reporter Seth Borenstein writes:

After looking at dozens of cases of suspected contamination, the scientists focused on eight hydraulically fractured wells in those states, where they chemically linked the tainted water to the gas wells. They then used chemical analysis to figure out when in the process of gas extraction methane leaked into groundwater.

"We found the evidence suggested that fracking was not to blame, that it was actually a well integrity issue," said Ohio State University geochemist Thomas Darrah, lead author of the study. He said those results are good news because that type of contamination problem is easier to fix and is more preventable.

The work was released ... by The Proceedings of the National Academy of Sciences.

Both of these studies call into question earlier research also published in Proceedings of the National Academy of Sciences. According to the American Association for the Advancement of Science, environmental scientist Robert Jackson of Duke University in Durham, North Carolina found that:

Analyses of 60 wells paint a picture of contamination near active gas wells. Almost all water wells more than a kilometer from an active gas well had only a few parts per million methane in their water. But most wells 1 kilometer or less from a gas well produced water with 19 to 64 parts per million methane. That’s at and above the “action level” of federal safety guidelines for methane, which can displace air’s oxygen to cause asphyxiation. The higher levels are also in the flammable range. “I watched one homeowner light his water on fire,” Jackson says.

So which research presents a more accurate picture of whether fracking is a danger to local drinking water supplies? Jackson's work was conducted on a much smaller scale, with fewer data points, but the new research lead by Siegel was supported and funded by Chesapeake Energy Corp.

For a better understanding of how the fracking process works, check out this video. Then share your thoughts in the comment section below.