Wastewater injection faces an uncertain future in West Texas’ prolific Permian basin, and companies working there will have to consider how else to dispose water produced by fracking, said Alex Archila, the asset president of shale at BHP Billiton, a Houston-based mining and exploration company.

“Water, as I said of the Permian, will be a huge issue past a certain amount that you can inject,” said Archila. “And then it will be other solutions that the industry will need to figure out.”

Archila, who spoke on a panel at the CERAweek energy conference, said companies working in the Permian face two challenges when it comes to water: getting enough water for fracking and getting rid of underground water released by fracking.

Typically, companies dispose of so-called wastewater but injecting it back underground, a process that has bee linked to earthquakes in some areas of the U.S. In response to concerns about earthquakes,  Oklahoma is considering limiting wastewater injection. On Wednesday, Archila suggested that there might be a limit to how much wastewater can be injected into an area.

The Permian is currently the hub of oil and gas in the U.S., where the majority of the country’s oil and gas rigs can be found. A CERAweek, there is even a word for the energy industry’s enthusiasm for the basin: Permania.