A Sacramento State project to map California’s groundwater resources, and to determine how they might be affected by the underground disposal of wastewater, has been awarded $660,000 by the U.S. Geological Survey (USGS). Led by Geology Professor David Shimabukuro, the project is the first launched under the auspices of the University’s Institute for Water, Energy, Sustainability, and Technology (iWEST).
Established last year, iWEST (csus.edu/iwest) focuses on advancing the sustainability of water, energy, and food systems by securing funding for and shepherding a collaboration of faculty, staff, and students involved in a series of research projects.
The first research project is being conducted by the Geology Department in the College of Natural Sciences and Mathematics in partnership with the State Water Resources Control Board and the USGS California Water Science Center located in Placer Hall.
When oil or natural gas is pumped from the ground, it frequently is accompanied by water that is not suitable for human consumption. It may be too salty or contain hydrocarbons.
Presently, that water is disposed of by injecting it beneath the ground into “water disposal wells.” While this works out if it is injected deep enough, or into areas where water already is in contact with petroleum resources or is too salty, that’s not always the case.
“The problem is, in this state, we don’t have a good understanding of where exactly these safe areas are,” Shimabukuro says. That’s where the professor and his team of about 25 sophomores, juniors, and seniors come in.
Using the oil companies’ own records, they meticulously are combing through documents that specify well depth, the type of rock structure surrounding the well, quality of the groundwater, and more.
The information will be used to make a map of California’s groundwater in sensitive areas and point out just where oil companies may dispose of the wastewater – and where it could contaminate usable groundwater.
Such information is becoming more vital given California’s drought. With less and less runoff into streams and reservoirs each year, groundwater becomes a more precious resource. Even subterranean sources that might be somewhat salty and previously overlooked could be desalinated at much lower cost than sea water, which has a much higher salt content.
Creating the map is painstaking. While most of the information is online and the documents have been scanned into PDF formats, each must be reviewed and interpreted by the researcher, then converted into a digital format to produce the needed information on salinity levels. And the state has flagged more than 100 oil fields for review.
“This is a long-term project,” Shimabukuro says, noting they can process only about four well fields a year. “It takes a long time to do this kind of science correctly. These records are sometimes more than a hundred pages long.”
While it’s going to take several years to complete, reports on individual oil fields can be used relatively quickly to start regulating the injection process. And even though the funding is only for one year, it is expected to be part of a three-year, $2.25 million agreement. “As long as the project continues to deliver things on time, it will move forward and will be a multiyear agreement,” says Geology Department Chair Tim Horner.
The severity of California’s drought has generated considerable interest in water projects, says iWEST Executive Director Debbie Whaley. “That’s where we’re seeing funding available right now and are really able to help faculty and students,” she says.
Shimabukuro especially appreciates how iWEST finds aid for professors, allowing them to spend more time on such projects.
“And we’re trying to find other opportunities to find research money so faculty can have more time to develop these projects with students,” Whaley says.
Such projects represent tremendous opportunities for students, especially undergrads. They get paid while learning more about their subject in a real-world situation. It not only augments their classroom studies, but gives them solid information for their résumés and an opportunity to flourish in their field.
“Over the course of this project I’ve had probably 10 students who have been co-authors or lead authors on scientific presentations at local, regional, or national geo-science meetings,” Shimabukuro says.