Reprinted with permission
Abandoned mines prone to flooding
By Joe Napsha
Monday, February 7, 2005
State officials say it's impossible to predict the next outburst of a flooded mine in western Pennsylvania, but a study of
underground mine pools from northern West Virginia to central Westmoreland County has found that abandoned mines are filling with an
estimated 1.4 trillion gallons of water.
"All of those abandoned mines have water pools to some extent," said Tom Rathbun, a spokesman for the state Department of
The mine water that burst out of the abandoned Nickel Plate Mine last month in McDonald, Washington County, caught officials by
surprise. There had been a small discharge from the mine, but no indication of such a buildup of water, Rathbun said.
No pool of water had been found inside the old mine when the state conducted a mine subsidence project there from 1988 to 1993,
"It's just impossible to know what's going on in these mountains," Rathbun said.
But a study conducted for West Virginia University's Water Research Institute digitized mine maps and computed data about
underground mine pools from northern West Virginia to the Export and Delmont areas. It found that between 1980 and 2002, mine
closures have resulted in rising water levels in mines throughout the region.
Active mines are pumped dry enough to allow mining operations to continue, but those pumps are shut off when the coal companies
leave, said Bruce Leavitt of Washington, Pa., a consulting hydrologist for the Water Research Institute.
The study identified more than 1,300 mines in an area stretching from Fairmont, W.Va., north to Pittsburgh, and from the
Greensburg and Uniontown areas west to the northern panhandle of West Virginia.
Researchers looked at the larger mines in the Pittsburgh coal seam, described in the study as "the single most valuable mineral
deposit in the world." Along the seam and in its basins, they found that small mines may be leaking into deeper ones, Leavitt said.
Groundwater fed by rainfall, streams and floods dumps even more water into the old mines.
Although the estimated amount of mine water tops a trillion gallons, Rathbun said the abandoned mines between the Ohio and
Monongahela rivers are so deep -- from 200 feet to 900 feet -- that water is unlikely to reach the surface, as it did in McDonald.
Instead, it remains in the abandoned mines because "there is no place for it to go."
But on the eastern side of the Monongahela River, the coal seams rise and "there are discharges all over the place,"
Water trickling from a mine "provides a relief valve so (the pit) doesn't fill up," he said, but those discharges dump untreated
mine water into streams and rivers.
The researchers' final report has yet to be released, but two years ago, the $2 million, multiphase study found that the
abandoned Shannopin Mine near Bobtown, Greene County, was close to flooding. Water now is being pumped from that mine and treated
before it is discharged into a stream.
Water also is rising at the Clyde, Gateway and Pitt Gas mine complex, also in Greene County, Leavitt said. The Mathies Mine, in
Washington County, bears watching, too, along with a couple of mines in the northern panhandle of West Virginia.
It is less likely that an outburst will occur at any of the abandoned mines in Fayette and Westmoreland counties, because most of
those mines are below the drainage level, said Joseph Donovan, director of WVU's Hydrology Research Center, which conducted the study.
The largest mines in Fayette and Westmoreland counties are so deep that water would have to flow upward before it could burst out
of the ground as it did in McDonald.
Still, "there's no shortage of old drainage spots," which are polluting the Youghiogheny and Monongahela rivers with mine runoff,
The WVU study reported that an estimated 17 billion cubic gallons of mine water discharges annually from the Pittsburgh coal basin,
about 50 percent of which is not treated. The researchers found that because the Pittsburgh coal seam has a moderate-to-high sulfur
content, it can produce enormous acid loads, and the drainage will continue to be acidic for years. The mine water can be high in iron
content, as well as other minerals.
The blowout at McDonald apparently was caused by a buildup of pressure that was not reduced sufficiently by the small amount of
drainage in one area, Donovan said. The mine water appears to have blown out at an old portal, he said.
Leavitt and Donovan, an associate professor in WVU's Department of Geology and Geography, were among several researchers from WVU,
Carnegie Mellon University in Pittsburgh and the University of Pittsburgh who worked on the study.
The Department of Energy, which provided funds for the study, is reviewing the final report before it is published.
The DEP is continuing to digitize mining maps, an effort started before the Quecreek mine flood in Somerset County trapped nine
miners in 2002. Rathbun said the state also wants to identify mine pools and other potential problems.
Joe Napsha can be reached at firstname.lastname@example.org or (412)-320-7993.