Researchers from Duke University plan to return to Pennsylvania next week to conduct additional testing of residential water wells in the northeastern part of the state, including wells that are not currently near any Marcellus Shale natural gas drilling.

Robert Jackson, a biology professor and the director of the university’s Center on Global Change, told NGI’s Shale Daily that he and about six other researchers will be in the state for about a week to continue sampling water wells that have been contaminated by methane and will try to determine the source of the stray gas. He said the team will also conduct some air sampling.

“We’re expanding our geographic coverage, working in additional counties,” Jackson said Monday. “We’ll be expanding from the original study area and going to the southwest.”

Duke released a previous study on the contaminated wells in May, which was derided as “biased science” by officials with the state Department of Environmental Protection (DEP) and caused a stir in the natural gas industry (see Shale Daily, June 8; May 11). The original study focused on Bradford, Lackawanna, Susquehanna, Wayne and Wyoming counties in Pennsylvania and neighboring Otsego County in New York.

Jackson acknowledged the criticism that was leveled against the previous study, including that it relied on a small sample of wells (68) and wasn’t performed by geologists. He said researchers would take baseline samples from water wells in areas where drilling had not occurred, sampling another 80 to 130 water wells this summer, as a way to address some of that criticism.

“We’re always looking for baseline measurements,” Jackson said. “We’re resampling some of our original baseline measurements, and taking some are in places that have since been drilled. We’re just trying to get more data.”

Jackson said Duke would more than likely release another report, possibly two, on the issue of the contaminated water wells before the end of the year. A separate report on air quality would be released sometime in the future.

“The project will going on for a couple [of] more years at least,” Jackson said. “It’s not disappearing anytime soon.”

Asked if he believed there was a connection between Marcellus Shale drilling and the contaminated water wells, Jackson said, “I think it’s very likely there is a link between what we’re seeing with stray gas in the wells. But that does not mean that I think it’s going to happen everywhere or in most places. And we’ve made it quite clear that in our study we did not find evidence that any fluids from hydraulic fracturing, production water or produced water had [contaminated water wells].”

He added that the DEP had conducted its own study of water wells being contaminated by methane gas back in 2009.

“That study documents dozens of cases,” Jackson said. “It’s not a new idea, really.”

For its part, the DEP had also criticized Duke for not sharing its data and sample locations with the state. Meanwhile another media report on the Duke researchers’ return to Pennsylvania quoted Jackson as saying the DEP and the natural gas industry have not shared data with him.

“It is true that to this point neither group has shared data,” Jackson said. “Part of that is just simply because these are private homeowner wells. We cannot share any of our data without homeowner permission.”

But Jackson said that within the past week, Duke researchers have sent a letter to every homeowner in the original study asking for permission to release the specifics of their test results.

“Any people who say yes, we will release [their data] publicly,” Jackson said. “Anybody who says no, we can’t legally or ethically release their data. Our intention is to make public as much of our data as we possibly can, and our target is to release all of our data.”

Travis Windle, spokesman for the Marcellus Shale Coalition (MSC), told NGI’s Shale Daily that the researchers’ return to Pennsylvania was a positive development.

“In admitting that they did not establish any baseline data in their five-page report [from May], the Duke researchers fundamentally put the cart before the horse in their claims that shale gas development and hydraulic fracturing were responsible for elevated levels of methane in selectively chosen private water wells,” Windle said Monday. “It’s our hope, however, that the group’s next trip to Pennsylvania will yield scientifically sound research, as we believe that lodging unsubstantiated and highly charged claims not grounded in facts is largely unnecessary.”

On July 20 Temple University announced that a faculty panel will investigate the source of methane gas that has contaminated water wells in Susquehanna County, PA (see Shale Daily, July 25). Meanwhile, the DEP said June 17 that it would try to determine how water wells and a nearby stream in Lycoming County, PA, have become contaminated by methane (see Shale Daily, June 20).