Darrell Sapp, Post-Gazette
	Firefighter George Rice, of Hickory, runs through the flowing waters on Liberty Street in McDonald. Neighbors were evacuated last week when the waters started to drain from abandoned Nickle Plate Mine in McDonald.

Polluted water gushing from the long-abandoned Nickle Plate coal mine through the streets of McDonald last week may have surprised people, but mining experts say the region will have to get used to wading through such "blowouts."

Abnormally high rainfall over the past year has raised the level of pooled water in more than 1,000 small, old, abandoned mines in southwestern Pennsylvania and northern West Virginia. The wet reminders of the region's mining past are likely to continue to bubble and blow out at a variety of surface sites through the spring.

In addition to the McDonald blowout, mine water was rushing out of the Maud Mine Complex and into Millers Run near Gladden on the Allegheny-Washington county line. And numerous discharges into Chartiers Creek are running at record high flows.

Paul Ziemkeiwicz, director of the National Mine Land Reclamation Center at West Virginia University, said precipitation last year was similar to the amount that caused numerous breakouts and blowouts in the spring of 1995.

"I would not be surprised if we see another cycle like that," said Ziemkeiwicz, who visited the McDonald blowout site Wednesday evening.

The Nickle Plate Mine operated in the Pittsburgh coal seam under relatively shallow cover, about 300 feet deep, from the late 1800s through the 1930s. Like other abandoned mines, it gradually has been filling with water since then.

A small discharge from the mine normally drains into Robinson Run, a highly polluted tributary of Chartiers Creek, southeast of McDonald, Ziemkeiwicz said, but the recent heavy rains and melting snow raised the pool level in the underground mine, built up pressure and popped out last week near the old mine entrance.

The flow was first estimated at 10,000 gallons a minute but soon declined to 4,000 gallons a minute.

"This is a real small mine and poorly mapped," said Ziemkeiwicz, who estimated it at between 600 and 1,300 acres. "I would be surprised if the heavy flow we've been seeing lasts very long."

Thousands of gallons a minute continue to pour from the Maud Mine complex blowout, caused in part by an unnamed tributary of Millers Run that was diverted into the mine when its natural channel was eroded by Hurricane Ivan flooding.

"Last week, 90 percent of that stream flow was going into the deep mine. It was going in clear and coming out polluted," said Bob Hedin, a local environmental engineer. "That mine complex is so full of water that it's coming out in several places that it didn't come out before."

The discharge isn't occurring in a town or residential area, so it hasn't received the attention given the McDonald blowout, but because it's full of acid, iron and aluminum pollution picked up during its trip through the mine, it poses a long-term threat to aquatic life in Millers Run and Chartiers Creek.

The South Fayette Conservation Group has applied for a state Growing Greener grant to fix the stream channel and stop the tributary from entering the mine.

Hedin said all the usual mine discharges in the Chartiers Creek watershed are running higher than any time since flow monitoring of the discharges started four years ago.

Despite the higher than usual levels of mine drainage, the pollution will have minimal effect on Chartiers Creek's recovering aquatic life and fishery because the creek is running at higher than normal levels.

"If this happened when flows were low, it would pose a problem. But Chartiers is flowing at 100,000 gallons a minute now and was at five times that last week," Hedin said. "All that dilution means that creek life won't be affected."

The trick will be making sure all the polluted mine discharges won't kill stream life in Chartiers and other creeks once surface flows return to normal.

Ziemkeiwicz said better monitoring of the region's mine pools was needed to identify spots where they might break out next. A research project to do that installed 25 monitoring wells but has run out of money.

"We've identified a couple of potential breakout points that could happen this year or in two or three years," he said. "More precipitation will shorten the time frame for that to happen or increase the volume of the breakout when it does occur."