UPPER DELAWARE RIVER VALLEY — Fracking may be a settled question and a banned activity along the Upper Delaware River, but elsewhere in the United States it’s a growing industry.

The Upper Delaware Council (UDC) heard a presentation about the wider world of fracking at its January 5 meeting. (The UDC also elected its 2023 officers at that meeting; see page 9 for more information.)

Dr. David Yoxtheimer gave the presentation before the UDC. Yoxtheimer is an assistant research professor and extension associate with the Marcellus Center for Outreach and Research at Penn State University; the Marcellus Center is the school’s energy education and research initiative. He serves as well as the chairperson of the Oil and Gas Technical Advisory Board, part of the Pennsylvania Department of Environmental Protection Office of Oil and Gas Management.

Marcellus Shale

The fracking that Yoxtheimer discussed largely took place within the boundaries of the Marcellus Shale gas reservoir.

The Marcellus Shale reservoir “is a very large shale gas basin, about 500 trillion cubic feet [TCF] of gas that can be recovered with today’s technology,” said Yoxtheimer. It stretches across most of Pennsylvania and into surrounding states, and has a presence in the Upper Delaware River Valley.

Other reservoirs exist within the region as well, including the Utica Shale reservoir, but the Marcellus Shale reservoir has been the most drilled in Pennsylvania. Currently, about 13,000 wells have been drilled into the various reservoirs under Pennsylvania, and current projections have shale gas production rising, increasing from 25 TCF to 33 TCF by 2050.

“On the energy standpoint, these are very strategic sources of energy,” said Yoxtheimer. “But again, obviously there are potential environmental impacts.”

Water management

Many of the environmental issues around fracking relate to the industry’s use of or impact on water.

The fracking process takes large volumes of water—mostly surface water in this part of the world—and brings it to a well site, mixing it with a range of chemicals, Yoxtheimer said. That treated water gets forcefully sent underground to open up fractures deep beneath the surface, allowing gas to be extracted; afterward, the water gets removed for reuse or disposal.

Each part of that process has the potential for a significant environmental impact.

Where the water for fracking comes from is a concern. In the Susquehanna Basin, the nearest Pennsylvania basin to the Upper Delaware, the third leading withdrawal of water is for the natural gas industry, around 24.3 million gallons per day or 10 percent of total withdrawals. This impact is overseen by state and basin-specific agencies, with regulations in place to govern the effect withdrawals can have.

The chemicals added to the fracking fluids are themselves a matter of concern. The industry tries to reduce their use, given their expense, said Yoxtheimer, and has released much of the data about their composition through databases like fracfocus.org. Some of the chemicals involved do however remain proprietary.

As the drilling process commences, it could contaminate groundwater around the drilling site. It’s not necessarily that fracking’s fractures let gas escape into nearby wells, said Yoxtheimer, but methane leaking around the well closer to the surface can pose a problem.

“This was an issue especially 14, 15 years ago when not as much was known about the subsurface geology,” Yoxtheimer said. “Some of the shallow methane especially caught the industry off guard; the wells weren’t drilled to contain it.” New regulations to seal off shallow gas during well construction, as well as industry-standard pre-drilling well testing, can help to mitigate these issues.

After fracking completes, the produced fluids that come out of a well contain both the chemicals that were used to treat the water pre-fracking, and the contaminants pre-existing in the earth, including salts, metals and radioactive substances. The industry treats and re-uses much of this fluid material, and has tried to increase that percentage. Whatever remains—around 6.3 percent of the fluids generated in PA in 2021—gets transported to disposal wells.

The transport of the fluids to injection wells carries with it risks of contamination; they get carried by trucks, which can lead to spills and leaks. On the other side, the disposal wells that take the final fluids simply put them back into the ground, many in depleted gas fields with emptied underground reservoirs. That process has the potential to cause seismic activity.

“These tend to be very controversial projects, as you can imagine,” said Yoxtheimer. “While the EPA will say that this is the safest way to dispose of these brines, the public might not exactly be buying that, and that’s understandable.”

Looking to the future

“There are certainly challenges. I’m not trying to minimize anything, but I’m also trying to say there are things we can do to minimize these risks and minimize the potential environmental impacts,” Yoxtheimer said. “Whether we want to admit it or not, this is an energy source that most of us use on a daily basis; we’re in an energy-hungry world, and we do have to find cleaner sources of energy and minimize the associated potential environmental impacts.”