Defining wastewater disposal in the Marcellus shale fields has been a moving target.

Drillers initially sent millions of gallons to public water treatment plants, until regulators said the plants were not equipped to properly clean the salt- and metal-laden water that comes from shale gas wells. The traditional method of injecting it back into deep wells is less feasible in Pennsylvania, which has few such wells, and Ohio is accepting less wastewater because of potential links between injection and earthquakes.

The search for a solution has spawned an industry of companies and innovators looking for ways to treat or reuse the wastewater that environmentalists feared would foul drinking supplies.

“They can barge all this water somewhere else or reuse it, which is what we're seeing now,” said Radisav Vidic, chair of the University of Pittsburgh's civil and environmental engineering program and a leading researcher on management of gas drilling waste.

Recycling wastewater from hydraulic fracturing in shale gas production has become the norm in the Marcellus and Utica shale plays. About 90 percent of what comes out of wells goes into the next job, Vidic said.

“What we call disposal is disposal to the generator. We find a home for it in the drilling fields,” said Andrew Kicinski, president of Collier-based Reserved Environmental Services, whose plants in Mt. Pleasant in Westmoreland County and in Butler County treat wastewater for companies including Range Resources, Rice Energy and Rex Energy. The company formed in 2006 but has been devoted to treating gas waste since 2009 and plans to expand.

At some point, though, the fields won't take it all. The industry, regulators and researchers must find a long-term disposal solution for when the amount of wastewater exceeds what companies need to continue drilling and fracking, environmental leaders say.

“It needs to be all of the above groups working together,” said Davitt Woodwell, president of the Pennsylvania Environmental Council. “Companies are trying to figure out what to do with this because handling water is so expensive. Regulators are looking for the best technology.

“The innovators are looking to find the next big thing.”

DESALINATION

Companies use up to 5 million gallons of water to frack a Marcellus well, typically drawn from a river or provided by a water company. About 30 percent returns to the surface in the first two or three weeks, during what the industry calls “flowback,” and more returns over years of production.

It's contaminated mostly with heavy salts from the shale, as well as dissolved solids, metals and sometimes radioactive material.

“The most difficult thing to get out is the salt,” said Tony Gaudlip, who as director of civil engineering and construction at Range Resources oversees water management at the state's most prolific shale driller.

Specialized treatment plants can take out the solids, metals and radioactive material, though salts remain. A report this month from Duke University said ammonium and iodides can remain. Pennsylvania does not allow treatment plants to discharge wastewater from fracking into waterways.

In looking at ways to potentially make the water safe to return to streams, Range decided to go the other way. Unlike the high-heat fracking prevalent in Texas, Appalachian shale extraction does not require pure water at the start, Gaudlip said.

“We said, ‘Let's just go with the waste streams we had available,' ” he said of the decision in 2009.

The wastewater can go right to the next job, where it's mixed with fresh or treated water for use in drilling or fracking, or to a treatment facility such as Reserved Environmental Services' plants before it's stored for another job, Gaudlip said.

The treatment gets the water clean enough for safe handling, though it remains a brine solution.

North Strabane-based Comtech Industries focuses almost solely on the gas industry. The company sets up centralized treatment operations to handle water from several sites at once for customers that include major producers such as Cabot Oil & Gas and Chevron Corp.

“We're able, based on those staging areas, to use three-quarters fresh (water) and 25 percent recycled on most wells, but we've done a whole frack on nothing but recycled,” said Cabot spokesman George Stark.

‘YOU BETTER GET BUSY'

Nobody can say how long recycling will remain viable. Kicinski, whose company plans to open a facility this year to keep up with demand, said he expects recycling to remain predominant for at least 15 years.

Whether companies will have an excess of wastewater on their hands after that depends on drilling and production levels.

Many say they can't wait until then to look for long-term disposal solutions, especially as deep-well injection falls out of favor. Grant Township in Indiana County is fighting in federal court a proposal to put such a well there. The Coast Guard has yet to rule on a proposal to transport wastewater by barges to other states.

“If you're projecting that that curve is going to happen in seven or 10 years, you better get busy now,” said Joe Tirreno, executive vice president of Comtech.

Researchers and a few innovators are focused on desalination technologies that can remove the salt as crystals, leaving behind other solids that can be taken to landfills, and distilled water.

“Crystallization, I've always thought, is the approach that will work,” Gaudlip said of several processes that produce salt ready for use on icy roads.

Fairmont Brine Processing has a plant in West Virginia that converts wastewater to salt crystals, sludge and distilled water by using pressure and heat, said CEO Dave Moniot. The process requires a lot of energy and several expensive plants spread across Appalachia to cut down on transportation, Vidic and others said.

“Those are big capital commitments. They'll want operators to sign commitments, and we still need water for the foreseeable future,” Gaudlip said.

Vidic received a $496,000 grant from the Department of Energy to explore a less-energy-intensive technology to remove salts by using low-grade heat from power plants to filter wastewater through membranes. Work on that just began.

Making desalination commercially viable will require finding uses for the resulting crystals beyond road salt, Vidic said.

“We will have to develop some chloride or chlorine-based industry to make from it,” he said.

“If someone wants to invest in that, you will have feedstock for as long as you want,” Tirreno said.

CONCERNS

Treated water can and has leaked while companies store it between jobs in tanks or earthen impoundments.

Range is installing double-liner systems with leak protection in its impoundments as part of a $4.15 million settlement with Pennsylvania over leaky pools. EQT Corp. is fighting a $4.5 million fine for leaks at its impoundments.

The state needs to do a better job of tracking what companies do with wastewater, said John Walliser, vice president of the Pennsylvania Environmental Council. The state Department of Environmental Protection is reviewing its reporting requirements.

“It's not enough to say, ‘We subcontracted that out for disposal' and leave it to someone else to report what happens,” Walliser said.

Trucking water to disposal sites raises the risk of spills, Woodwell said.

The goal should be a technology that gets wastewater back to a state in which it is safe to return to the hydrologic cycle, he said.