Mining operations’ legacy a mother lode of acid drainage
Restoration efforts slowly bringing back creeks that have been dead for decades
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There are places in the Chesapeake Bay watershed where bright orange streams go largely unnoticed.
No one living among these rural towns and country roads can recall anything else. The rush of pumpkin-colored water, a legacy from long-abandoned coal mines, has washed away any hope of a fishing hole or swimming spot for so long that few people imagine anything different.
The odd color signals a host of problems. The orange hue, and its many variations, comes from the presence of heavy metals that often make the water too acidic for fish and leave the streambed void of important insect life.
In the mountainous regions of the Bay watershed, some streams have run orange for more than a century. Generations of people have come to not expect clear water, much less fish.
So when the orange fades and the fish return, it's a show-stopper.
The fish in Babb Creek, a northern Pennsylvania stream, have enjoyed such a comeback. Not long ago, the creek was the victim of heavy mining operations, most of which closed a century ago.
"There were about 13 miles of the mainstem and four tributaries that were totally dead," said Bill Beacom of the Babb Creek Watershed Association. "There were no fish, no insect life, nothing. Most people said there's nothing you can do about it, it's such a big problem."
Aggressive cleanup efforts began in the 1990s. The first signs of reproducing trout appeared by 2000. Last year, Babb Creek was reclassified as a wild trout stream.
"People just can't believe it," Beacom said. "I fish there all the time. It's great."
Efforts to clean up the damaged streams have delivered similar results in select areas of the Bay region. Some recent research suggests they may be helping the Bay cleanup as well. The success stories, though, pale against the scope of the problem.
Acid mine drainage has devastated at least 1,100 miles of streams in the Bay watershed, and at least 5,000 miles of streams in Pennsylvania as a whole. At least 450 miles of streams are impacted in Maryland.
According to a 1999 report from the Chesapeake Bay Program, "Acid mine drainage from abandoned coal mines has been considered the most severe and extensive water pollution problem in western Maryland, West Virginia, and northeast, north central and western Pennsylvania."
Most Virginia streams impacted by mine pollution are not in the Bay watershed.
Repairing the full extent of damage is difficult for many officials to imagine. The effort would require billions of dollars and could take a century or more of ongoing treatments.
Yet some local level results deserve celebrating. In a painstaking, site-by-site crawl along targeted streams and rivers, state, federal, and local groups have stretched limited funds into a chain of treatment projects that have succeeded in reviving these once-dead waterways.
And more help is on the way. Recent changes in the federal Surface Mining and Control and Reclamation Act have increased the funds available for these projects and raised hope that more success stories lie ahead.
The act, first passed in 1977, collects fees from coal companies to clean up mine-related damage to landscapes and waterways. The bulk of the funds have removed high walls, drainage pits and other features of old mine lands that threaten public health and safety. Only 10 percent of the money could be used to address water quality problems.
In 2006, an aggressive multi-year campaign led by the Pennsylvania Foundation for Watersheds (formerly the Western Pennsylvania Watershed Program) helped to raise that allowance to 30 percent. The change will bring millions of additional dollars to ailing streams in the Bay watershed.
"This was citizen-based action that affected national public policy," said campaign chairman John Dawes.
The revised act also calls for mandatory spending of the funds, which better ensures that the money will reach the states as intended. Previously, advocacy groups endured an annual, time-consuming approval process with congressional committees that met with varying success. Funds were often withheld or diverted to other projects.
"In recent years, Pennsylvania received an average of only $22 million per year to deal with a multibillion dollar problem," Dawes said.
The revised act promises Pennsylvania approximately $1.4 billion dollars over the next 14 years. Up to 30 percent of each year's funding can be used to treat acid mine drainage.
"The passage of this legislation at the federal level is one of the most important environmental acts for Pennsylvania in the last two decades," said Brian Hill, president of the Pennsylvania Environmental Council. "The 30 percent set-aside is essential for Pennsylvania."
Maryland, with far fewer coal mines than Pennsylvania, will see funds for acid mine drainage increase from roughly $60,000 to $180,000 per year.
The broth that clouds the water and coats the bottom of Chesapeake tributaries is found mostly in two areas. The first is in the Susquehanna River basin, especially along the West Branch. The second is in the Potomac River basin, along the North Branch in western Maryland.
Water leaking and sometimes gushing from the old mines carries a toxic mix of metals such as iron, aluminum and manganese. The metals make the water acidic and smother the streambed with thick residue. This creates the disturbing orange hue and its many variations, known as "yellow boy" or "red boy." When aluminum dominates, the water may turn milky white or remain clear. But the results are the same: a biological wasteland.
Because the impacts of acid mine drainage (AMD) are felt mostly upstream of the Bay, it hasn't been a priority for regional cleanup efforts. No one knows how much of the metals from AMD reach the Bay itself or the level of threat they pose.
The Bay benefits from its location-the farther away from the mine sites, the more likely that natural processes will dilute and neutralize metals in the water. Meanwhile, a 1999 report from the Chesapeake Bay Program called for more research on the subject.
"Acid mine drainage isn't a significant concern for the Bay," said Richard Eskin, of the Maryland Department of the Environment, and the former chair of the Bay Program Toxics Subcommittee, "but it's not something we should ignore either, not if we want to talk honestly about fixing watersheds."
AMD is the legacy of mining operations from before 1977, when federal regulations began to hold the coal mining industry accountable for preventing and repairing the problems left in its wake.
Most of the mines causing today's problems closed in the late 1800s and early 1900s, but thousands of miles of underground tunnels still exist. Water accumulates in the tunnels and rises to the surface. It might trickle from spring-like openings in a hillside or seep down an exposed rock face as a thin sheet. It might also erupt violently from the mouth of a mine tunnel. The Jeddo Tunnel in Luzerne County, PA, spews 40,000 gallons of water per minute into the local creek.
Robert Runowski, a senior scientist with the EPA, said the problem is almost impossible to overstate.
"It's not just big. It's convoluted," he said. "Underground accumulations of water can go virtually anywhere. You end up with discharges eight, 10, 12 miles from the mine site. In areas like northeastern Pennsylvania, where the industry has been going since the 1850s, you have 150 years of environmental impact to deal with."
The treatment of AMD is a game played with many moving and uncertain pieces. The goal is to neutralize the acid content of the water and remove the metals. But the treatment process must be adapted to the specifics of each site-not just one solution for each mine, but a series of solutions tailored to each outflow point at the site.
The amount and type of metals in the water shape the treatment options, as well as the rate and volume of the flow. The choice also depends on the physical space available for the project, the degree of landowner cooperation and the amount of money available.
"You have a goal, to sequester the metals and elevate the pH (a measure of acidity)," Runowski said, "but it's a very involved process in trying to tailor the treatment to the community's problem. No one size fits all."
Diverting streamwater over beds of limestone is one of the simpler options. The natural properties of limestone neutralize the acid in the water before returning it to the stream. The water can also be flushed through limestone in pipes, chambers and wells.
Settling ponds and constructed wetlands can also treat AMD. They retain the water for longer periods of time, allowing plants and bacteria to play a role in neutralizing the acid and providing time for the metals to drop out of suspension.
Costs for individual treatment projects sometimes total tens of thousands of dollars, but often reach $200,000 or $300,000. Settling ponds slated for the Bear Creek watershed near Harrisburg are projected to cost $350,000. Large or technically complex systems cost millions. The physical removal of an 18-acre pile of coal waste in the West Branch headwaters is expected to cost approximately $4.4 million.
Once in place, treatment systems need ongoing maintenance. This might mean a weekly visit to replenish limestone or the monthly flushing of metallic sludge from a piping system. It might also mean the occasional scouring of a constructed pond or wetland, where metals have dropped out of the water and begun to coat the bottom. Partners in the Babb Creek watershed spend approximately $50,000 each year on maintenance.
The source of acid from a particular outflow can eventually be exhausted, but may take decades-or even centuries-to happen.
"Treatment is expensive and perpetual," Runowski said.
As a result, officials say the total cost of constructing and maintaining systems to neutralize all AMD discharges in the region would easily reach billions of dollars.
Despite the challenges, the need to address AMD has drawn increasing attention, in part because of the multi-state campaign that renewed the Surface Mining Control and Reclamation Act. People are also pointing to AMD sites for the potential benefits that treatment can bring to both the environment and the economy.
Restoring AMD waters, for example, could support the public water supply. Restoration on Swatara Creek, an eastern tributary to the Susquehanna, was driven for decades by the need for clean lake water in a proposed state park.
On the West Branch, the state and the Susquehanna River Basin Commission have partnered on a $6.1 million project that will treat 10 million gallons of AMD water per day. The treated water will be used to make up for river water used by farmers during drought.
Dredged material from shipping channels or fly ash from coal-burning power plants could possibly plug up old mine tunnels. This would support other industries and might also stabilize the land for development.
Approximately 150 Pennsylvania community groups have made AMD their primary focus, helped by regional organizations such as the Eastern and Western Pennsylvania Coalitions for Abandoned Mine Reclamation.
"Citizens in the coal field communities have paid the price for coal extraction that took place during the Industrial Revolution," Dawes said. "They have been owed this in terms of their health and safety and also in terms of property value. It's difficult to attract new residents and businesses to a degraded environment."
Restored AMD streams could also return a range of ecosystem functions to the watershed, such as reducing nitrogen pollution and providing fish habitat. Most AMD streams are located in forested areas with excellent potential for fisheries-good not just for wildlife, but for tourism.
"We're looking at 4,600 miles of dead streams in Pennsylvania," Dawes said. "It's pretty important as a revenue source to bring those streams back to life."
Recreational revenue is a major driver of AMD efforts on the West Branch. The West Branch runs through more than 2 million acres of public land with stunning mountains, dark nighttime skies and the largest elk herd this side of the Mississippi. But the area, marketed to tourists as "Pennsylvania Wilds," also has significant problems from AMD. The Pennsylvania Fish and Boat Commission estimates that more than $16 million dollars of potential recreational revenue are lost there each year because of AMD.
In 2004, a major West Branch restoration initiative led by Trout Unlimited linked up with Gov. Edward Rendell, who is working to boost outdoor recreation and ecotourism. "The governor visited the area and learned about AMD," said Amy Wolfe of Trout Unlimited. "He saw the potential."
Trout Unlimited and Pennsylvania state agencies are now among the 13 partners spearheading restoration plans for the West Branch. Projects and assessments are under way in at least a dozen West Branch tributaries, supported by watershed groups and conservation organizations. "One of the really good things about the West Branch is that most of the instream habitat is already intact," Wolfe said. "That's phenomenal. You just don't find that in other areas. Water quality is the only limiting factor."
Babb Creek was one of the first West Branch watersheds to see the return of native brook trout after AMD treatments. Good results are starting to show in Kettle Creek, too. Treating one AMD drainage site restored water quality in 2,500 feet of the stream. Brook trout and aquatic insects returned within a year.
Wolfe hopes that some of the new federal dollars will be put to work on the West Branch. And while comprehensive restoration costs are estimated at $279 million to $464 million, targeted efforts can deliver clean water in the mainstem and several tributaries for much less.
"It's important for people who have grown up here and accepted these nearly dead streams as a way of life to understand that it doesn't have to be that way anymore," Wolfe said. "Remediation technology has come a long way, and we have more hope now than ever to restore this region's potential."
Joe Mills, who works with the Maryland Bureau of Mines, offers direct testimony to the highs and lows of AMD restoration. For 15 years, he has studied, repaired and nurtured AMD streams feeding the North Branch of the Potomac.
Georges Creek is among his charges. Beginning in the 1990s, a series of treatment projects lowered acidity in the creek, with the Georges Creek Watershed Association as an active partner.
Their efforts brought both native and stocked fish into waters where aquatic life is said to have vanished by 1907.
"The old timers can't remember ever catching fish here until five to seven years ago," Mills said.
One stretch of the creek was notoriously acidic but was responding to treatment. Then, water flowing through the underground tunnels played the worst trick of all: It moved. Out of sight, deep within the old workings of the mine, something shifted. Mills will never know what caused it, but the results were clear.
A modest outflow erupted-downstream of the treatment station.
"We went from 60 gallons per minute to 250 gallons per minute," Mills said. "The water was like tomato soup. The metals were floating by in chunks."
The burst occurred when the creek was extremely low, which intensified its effects. Two days earlier, the watershed association recorded a pH reading of 7.5. Afterward, the level fell to an acidic 3.0-about the same pH as vinegar.
"It was a shock to the system," Mills said. "We had four miles of dead stream and dead fish, from here to the Potomac."
The outflow has slowed slightly since then, but still averages 200 gallons per minute. Stocking was stopped until Mills adjusted the treatment strategies to deal with the higher flow and increased acidity.
Morale suffered over the incident, but Mills touts a broader perspective. "In an odd way, we should be proud of that fish kill," Mills said. "Ten years ago, there were no fish here at all. Ten years ago, nobody would have noticed it happened."
The complexities of AMD mean that the successful efforts must draw on a wide range of groups and funding sources.
Community groups that tackle AMD projects need help from technical experts at government agencies or larger conservation organizations. In return, local groups add resources that government agencies can't offer-they raise and accept grant money, rally community support and provide volunteers.
Funds may come from the Surface Mining Control and Reclamation Act, but not always. The EPA and U.S. Geological Survey also fund AMD projects, as do state initiatives such as Pennsylvania's Growing Greener program. Private grant makers and businesses also contribute. The Pennsylvania Foundation for Watersheds is a major source of matching funds for restoration grants awarded in Pennsylvania.
The modern coal industry also enables restoration projects, both through fees that support the Reclamation Act and by conducting restoration projects in lieu of fines. Sometimes they support local projects just to be a good neighbor.
"It's a delicate balance among public, private, local and government entities," said the EPA's Runowski. "No one entity can address this issue well. You need public education, monitoring, resource management and technical assistance."
When the partnerships combine well, they can produce an impressive recovery. The Swatara Creek watershed, just north of Harrisburg, is one of the lucky ones.
Restoration there was led by Pennsylvania state agencies, which at one time hoped to tap the watershed for a new public reservoir. The upper 43 square miles of the watershed, though, were polluted by AMD.
"The Swatara was solid orange," said Dan Koury of the Pennsylvania Department of Environmental Protection. "The Lorberry Creek tributary was black from silt, and a solid line formed where they met. Habitat was dead."
Efforts to improve water quality converged on the Swatara beginning in the mid-1990s. The projects drew approximately 50 partners, including the USGS, EPA, U.S. Department of Energy, Schuylkill Conservation District and a newly formed watershed association.
Twelve treatment systems now operate there. The most critical water quality projects drew on approximately $4 million from state, federal and private sources. Since 2000, an additional $6 million in reclamation work has been supported by the Reclamation Act.
There have been challenges, including an outburst like the one at George's Creek that washed support timbers from a mine tunnel onto Interstate 81. There are persistent problems from the two largest discharges in the watershed. Yet the Swatara has made a comeback.
"You'll still see orange in the headwaters, but a lot of systems are in place to neutralize it," Koury said.
USGS scientists have documented more than 20 fish species living in the Swatara near the mined part of the watershed-none existed in the 1980s.
"A lot of people said that fish would never live in there," Koury said. "Then we got a call that someone caught an 18-inch fish in the creek behind their house, and the calls kept coming in. It was a big deal."
Partnerships and volunteers were critical. Several government agencies provided cleanup money. The local watershed association launched its own hatchery. A landfill operator helped with equipment and materials. Sportsmen's clubs, private citizens and even the National Guard donated labor, supplies and technical advice.
"You always need something you didn't factor in," Koury said. "If a storm wipes something out, the funding may not be there to fix it. Hurricane Ivan started carving away one of the main treatment systems near I-81. My heart dropped when I saw it. Then one of the township folks came out with a backhoe and fixed the problem. There was no charge. He did it because people appreciate what's been done out there."
Koury looks forward to seeing the new federal funds support AMD work across the state, and possibly boost work on the Swatara. The Pennsylvania Department of Environmental Protection is scheduling a series of public meetings to help decide where and how the money should be used. "Everybody has ideas on how to spend it," he said.
Air, Pyrite & Water: Recipe for Disaster
Problems from acid mine drainage don't come directly from coal. They come from what lies in and around it.
Pyrite, also called fool's gold, is commonly found in coal seams and neighboring rocks. Mining breaks open the rock, exposing pyrite to air and water.
Pyrite reacts with air and water to create sulfuric acid. Naturally occurring bacteria in coal waste products, left behind as refuse piles, speed the acid- forming process. The acid can dissolve heavy metals such as iron and aluminum and leave them suspended in the water.
As the stream becomes more acidic, it supports fewer fish, plants and insects. As iron and other metals drop out of the water, they coat the streambed in a thick layer of rusty orange paste that damages or destroys aquatic life.
AMD is mainly associated with abandoned mines that were developed before regulations to control pollution. The mine tunnels, once pumped free of groundwater, have become huge underground waterworks, often unmapped and unpredictable. The discharge of water from these tunnels can be as large as the streams they enter.
Acid Mine Drainage & The Chesapeake
Acid mine drainage is a major pollutant in some Chesapeake Bay tributaries, but not in the Bay itself. Because of this, AMD has traditionally played little to no role in regional Bay cleanup strategies.
But a study in northern Pennsylvania may challenge that logic.
Matthew McTammany of Bucknell University and Steven Rier of Bloomsburg University are working with the Stroud Water Research Institute to explain how restoring AMD streams may help the Bay-not by reducing metals in streams, but by restoring stream systems that in turn reduce nutrient pollution entering the Bay.
Healthy streams are highly effective at storing and filtering nutrients. Their floodplains and buffers are filled with trees, plants and bacteria that take up nutrients that would otherwise enter the waterway.
When AMD destroys stream life, it also wrecks the natural processes that reduce the movement of nutrients downstream. McTammany, Rier and Stroud researchers are exploring how well restored AMD streams recover their ability to process nutrients.
"It's an exciting possibility that remediating mine drainage might restore ecosystem functions in streams," McTammany said. "If we fixed up all the AMD up here, what would it mean to the nutrient load for the Chesapeake Bay? It might become another tool in the portfolio of nutrient reduction strategies."
Mixed Bag Of Tricks Used To Treat Acid Mine Drainage
Treating acid mine drainage hinges on two factors: neutralizing the acid and coaxing the metals out of the water. One step might be needed, or both. It depends on what's in the outflow.
"The science on treatments isn't perfect yet," said Charles Cravotta of the U.S. Geological Survey. "There's a lot to be studied, discovered and documented. And funding is limited."
Limestone is often used in treatment systems because it neutralizes acid. Polluted water is directed over beds, channels, wells and drains lined with limestone. The limestone dissolves as the water passes through it, producing alkalinity and reducing the acid. Limestone sand can also be loaded directly into the stream. These projects are less costly, but the stone and sand need to be replenished regularly. Also, large outflows require large treatment areas, which don't always exist at the treatment site.
Caustic soda, soda ash and ammonia can also help to reduce acidity, but these substances must be handled very carefully in contained environments. Constructing and maintaining such systems can be expensive.
Over the last 15 years, treatments have focused not only on limestone but on constructed wetlands and settling ponds that treat AMD through natural processes. These systems collect and slow the water, so that nature has more time to work.
An aerobic wetland is used for removing metals from water that does not have major acidity problems. The plants and increased levels of oxygen make the metals drop onto the wetland floor while cleaner water slowly exits the wetland and rejoins the stream. The metals must be occasionally cleaned from the wetland floor.
Settling ponds, or compost wetlands, are deeper than aerobic wetlands and lined with a thick layer of compost. The water is moved through the bottom of the pond, where microbes in the compost work to remove iron and other metals.
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