Drilling water recycling process 'a win-win for everybody'
When drillers began exploring the Marcellus shale, they thought they could use only fresh water in their hydraulic fracturing of rock to release the natural gas trapped inside.
So they transported the water that flowed back from the fracturing process to treatment facilities, which would try to remove salt and chemicals before releasing the water into streams and rivers -- as industries did for years.
"Our streams and rivers, they can only take so much of that saltwater, so we advocated stopping that practice," said Matt Pitzarella, spokesman for Texas-based drilling company Range Resources, which has an office in Cecil.
At the state Department of Environmental Protection's request in May, drillers stopped taking wastewater to treatment facilities that dispense it into waterways.
Now, Pitzarella said, every driller operating in the state recycles a portion of its flowback water for reuse in drilling.
"Probably 75 to 80 percent of the water is being recycled for fracking," said Lou D'Amico, president and executive director of the Pennsylvania Independent Oil and Gas Association. "They remove free solids and things like that, and just return it back to a location and repump it in the next frack job."
The recycling process is simple but innovative, said Andrew Patterson, executive vice president for technical affairs for the Marcellus Shale Coalition, an industry group.
"People thought the saltiness of that flowback would make it difficult to do fracking because it's a different composition than fresh water, but that's what the innovation is -- you can use salty water," Patterson said. "You're basically returning it to where it originated."
Hydraulic fracturing, or fracking, involves pumping millions of gallons of water with sand and chemicals underground to break apart the rock and release natural gas.
About 10 percent to 20 percent of that water -- amounting to several hundred thousand gallons -- flows back to the surface immediately and operators capture it in tanks. The flowback water contains salt because the Marcellus shale was an ancient seabed.
Each drilling operator has a different process for recycling that water, but most follow the concept of filtering out solids and combining the water with fresh water in the next fracking job, Patterson said.
"Really, all you're trying to do is trying to remove things that you don't want to have to deal with when you're pumping it back through your system and putting it into another well," Patterson said. "Because you're using the water for another frack, the amount of treatment you'd need is fairly small compared to treatment needed for potable water."
Pitzarella said Range Resources' method of recycling uses connected tanks that remove solids, including minerals, excess salt that does not dissolve and drill cuttings. The water passes through filters as it flows up and down the tanks.
"By the time it gets to the last tank, all the solids are removed," Pitzarella said.
The company takes the solid waste to a landfill, he said.
"It ends up being a good thing for the environment, because you're using less fresh water, and it's also economical for the producers because they don't have to truck as much water to a disposal facility -- and so it's a win-win for everybody," Patterson said.