Geologist studies impact of hydrofracking on groundwater
Master’s graduate Craig Joseph, a participant in the National Energy and Technology Laboratory Postgraduate Research Program, uses his academic background in marine geology to help predict how hydrofracking will affect groundwater. To extract natural gas, the industry injects fracturing fluid into the earth at high pressure to shatter the rock deposits and release the natural gas. When the fluid resurfaces, it has the potential to carry contaminants that could be deposited into the environment. Above, he prepares a sample dilution for elemental analysis.
Several years ago, Craig Joseph rode his bike through his college-town streets in Morgantown, W.Va. Nearby, a stream flowed bright orange with acid mine drainage, a phenomenon common for one of the nation’s top coal-producing states. Joseph paused to watch a few kids play in the stream. After years of scuba diving, swimming and rafting, this moment culminated his personal and academic interest in water: its movement, its chemistry and any chemicals within.
Sustained by this curiosity, Joseph obtained a master’s degree in marine geology from Oregon State University, where he studied how fluids migrate through the oceanic crust and into the ocean. He conducted his research as part of the National Energy and Technology Laboratory (NETL) Professional Internship Program (PIP), managed by the Oak Ridge Institute for Science and Education. After nearly three years in the PIP program, he transitioned to a NETL postgraduate researcher through the NETL Postgraduate Research Program in April 2012. His current goal is to conduct a baseline analysis of the impact hydrofracking the Marcellus Shale has on groundwater.
“Currently, we are developing experimental methods to analyze metal mobility and potential sources of groundwater contamination during hydrofracking operations within the Marcellus Shale,” he said.
The Marcellus Shale is a formation of sedimentary rock stretched across eastern North America. The most recent U.S. Geological Survey assessment estimates the shale contains about 3.4 billion barrels of natural gas liquids.
“We are trying to get an idea of how drilling into shale gas formations like the Marcellus Shale is influencing the world around us,” said Joseph.
Ideally, his research could be used by drill operators to minimize potential environmental impacts of natural gas extraction.
To extract natural gas, the industry uses a process called hydraulic fracturing, or hydrofracking, which injects “fracturing fluid” among other inputs at high pressure into the earth to shatter the rock deposits and release the gas. When this fluid resurfaces, it has the potential to carry contaminants that could be deposited into the environment.
“I have developed a few different laboratory experiments where we are looking at what metals and other elements get liberated when the Marcellus Shale—which hasn’t been exposed to oxygen for hundreds of millions of years—is exposed,” he said.
One of these experiments subjects a sample of the Marcellus Shale to various fluids in a high-temperature, high-pressure setting to simulate what happens to it thousands of feet below the surface. During the course of a few weeks, he can develop a time-resolved analysis of which contaminants, if any, leach out. His hypothesis is that the shale formation contains certain metals like lead, chromium, uranium and arsenic.
“When certain metals are exposed to different types of fluids, particularly if oxygen is introduced into the system, these metals may change form and be rendered mobile,” said Joseph.
His time at NETL is split between his computer and hands-on research in the safety-goggles setting. He develops research methods, then implements and improves upon those methods in the lab.
“The tools that I am using can be applied to a wide variety of environments where element mobilization and environmental impacts of fluid-rock interaction are of concern, including coal mines, offshore or onshore oil wells and geothermal energy wells,” he said.
He also gets to network with microbiologists, chemists and other scientists whose research focuses on the Marcellus Shale.
“Gaining the experience at NETL with people who have been in the research sciences for many, many years—and having the ability to collaborate and learn with them—has been beyond helpful,” he said. “The insight gathered from each of the disciplines can be combined to form a holistic understanding of the impact of natural gas drilling on the environment.”
By the time the program ends, Joseph hopes to look back and see that he contributed meaningful, impactful research to the larger body of knowledge surrounding geological systems.
“Eventually, I plan to start my own geologic and environmental consulting firm; I am considering going back to school for a doctorate degree,” he said. “For the meantime, I am using research at NETL as a way to diversify my understanding of different experimental and analytical techniques.”