A consortium of five universities is testing possible new methods for removing moisture from coal slurry, state lawmakers heard Tuesday at a committee meeting that heard about emerging technologies.
A session of a joint interim committee received updates on research advances and also the continuing complains of constituents who say a coal byproduct has polluted their drinking water.
Washing coal with water and chemicals helps it burn more efficiently, but leaves behind a wastewater containing heavy metals and other toxins.
Coal operators store this slurry in ponds or inject it into worked-out underground mines. Injection relies on troughs dug into sealed mine voids, which in theory hold the waste and allow solids to settle to the bottom.
The industry maintains this practice is safe. Critics allege that natural settling or such activity as blasting can allow injected slurry to leak into nearby groundwater.
Roe-Han Yoon, a professor at Virginia Tech, is director of the five-school Center for Advanced Separation Technologies that's leading university research on new methods to extract the moisture from slurry.
He told Tuesday's committee of one process that employs a centrifuge to dry out coal waste. Consortium researchers are pursuing a patent for a separate dehydration process that could be performed by a portable, trailer-sized machine, Yoon added.
Potential profits would spur coal companies to embrace such methods, Yoon said. From four billion tons of waste, this new technology could recover 1.4 billion tons of fine powdered coal, he estimated.
"I call it a treasure box, if we have the right technologies," Yoon said.
The lawmakers also heard from former state Sen. Russ Weeks, R-Raleigh, who said he's been working with his son on a process to convert slurry into a solid.
Weeks said he and his son are also seeking a patent for their chemical formula. Holding up a sample of hardened slurry, Weeks said their formula could be applied as slurry is injected underground.
"This would preclude it from getting into the water table," he said.
Only a dozen coal operations continue to inject slurry, the state Department of Environmental Protection reports. DEP blocked new sites last May, after issuing a report that found no evidence of slurry migrating underground.
The agency has since launched a more detailed investigation of slurry and groundwater in Boone County, which leads the state in coal production.
West Virginia University, part of Yoon's consortium, has been studying whether underground injection poses a threat to human health.
Several members of the Sludge Safety Project urged lawmakers at Tuesday's meeting to pursue alternatives to injecting or impounding slurry.
Representing coalfield residents, these speakers presented jars of murky water from area taps while recounting the array of health ailments blamed on slurry pollution.
"Nobody on Prenter Road has their own gall bladder," said Pam Johnson, a nurse. "Not many 5-year-olds require dentures, except in Prenter Hollow."
Residents of Prenter and Seth, both in Boone County, are suing eight coal companies they believe poisoned their wells by pumping coal slurry into old underground mines.
Jason Bostic of the West Virginia Coal Association said operators would welcome methods to help them recover more coal. But he said that every coal seam in Appalachia contains materials that cannot burn and so must be removed when the coal is processed.