New Information From Old Mine Maps

A new partnership will make maps of abandoned mines more accessible to the public. The information is proving useful to homeowners who live atop old mines, and even to developers of a new regional botanical garden. The Allegheny Front's Leah Kauffman has the story.

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OPEN: A new partnership will make maps of abandoned mines more accessible to the public. The information is proving useful to homeowners who live atop old mines, and even to developers of a new regional botanical garden. The Allegheny Front's Leah Kauffman has the story.

KAUFFMAN: Our region is riddled with abandoned coal mines. Invisible far beneath us, we're often unaware of old mines until one subsides or collapses -- damaging roads, homes, and other buildings above. At the Pennsylvania Department of Environmental Protection, Jim Welsh explains the extent of the hazard.

WELSH: We estimated a few years back that there is approximately a million homes at risk.

KAUFFMAN: Private homeowner's insurance usually won't cover mine subsidence, but the DEP has a program that does. Welsh is using new data from old mine maps to help people decide whether to buy mine subsidence policies.

WELSH: Right now there's approximately 59,000 policies in effect in Pennsylvania. So Pennsylvania is very much underinsured.

KAUFFMAN: Recently, CONSOL Energy, along with the DEP and the federal Office of Surface Mining, pledged $200,000 to help insure that a special collection of CONSOL's old mine maps can be conserved by the University of Pittsburgh and scanned. The state will add those scans to an ever-growing database that people can access online to learn if their property has been mined. Jim Welsh says this project is particularly important because it focuses on so-called hardback maps, five-foot-wide paper maps glued to canvas, sometimes more than 30-feet long.

WELSH: When the foremen come out at the end of the day, the surveyors came out at the end of the day, this is the map they updated. And then they did tracings off of this map to turn into the government or their investors.

KAUFFMAN: These are the master maps of the mine. They're the most complete, up-to-date records of a mine's ever-changing, otherwise hidden features. Fortunately, CONSOL, the largest mining company in Pennsylvania, has donated more than 700 of the maps to Pitt's archives. Unfortunately, they generally arrive in pretty bad shape. Most are frozen into tight rolls, grown brittle with age and covered in coal dust. Amy Baker is the conservation expert at Pitt who brings life back to these maps, some of which are over 150 years old.

BAKER: If you try to unroll this map, it would just crack about every four inches. So in order to unroll the map safely, we place them inside the humidity dome.

KAUFFMAN: Baker describes the humidity dome as a giant air hockey table filled with water vapor.

BAKER: Little by little, as the humidity is introduced, those paper fibers relax, the adhesive soaks up some of the moisture, and we're able to unroll it safely without cracking.

KAUFFMAN: When a map is pliable again, Baker removes it from the dome and flattens it out, drying it slowly so it doesn't curl up again. Once dry, the maps are cleaned of years of coal dust. Baker won't try to make each map pristine, but it is important that enough dirt is removed that a scanner can pick up details like letters and numbers.

BAKER: They're so interesting and I mean they're all done by hand, and so, sometimes they just look like works of art.

KAUFFMAN: Once restored, the maps are transported to the Office of Surface Mining in Greentree. There, Paul Coyle's team has a room-sized scanner.

COYLE: This is the national mine map repository for the whole country. We have a machine that can scan an area of 60 by 90 inches. We take the electronic data and also convert it to microfilm. Microfilm will last 500 years.

KAUFFMAN: The physical maps return to Pitt's archives, and the scans are shared with the DEP. Builders and developers also use the maps to identify and deal with mining-related hazards. Lindsay Totten is one of those developers. She's part of a nonprofit organization hoping to build the area's first outdoor botanical gardens, planned for Settler's Cabin Park west of Pittsburgh. First, the group has to solve a big acid mine drainage problem on their land. The conventional solution is to treat the water that comes out of the mines, but they're taking a more radical approach. They'll return to the old mines, take out the pillars of coal that were left behind, and fill in the voids with earth.

TOTTEN: We call our project reclamation because we are not doing it to retrieve the coal. What we are doing it for is to reclaim the land and get rid of the polluted water that the mines are creating.

KAUFFMAN: To determine whether their plan was economically feasible, to get a permit to begin work, and to make the reclamation work as safe and efficient as possible, the Botanic Garden needed to know where the mines were, and where coal might still remain.

TOTTEN: It became very apparent that we were going to have to find the mine maps so that we could see what was underneath the ground.

KAUFFMAN: After a long search for maps of the Botanic Garden site, the DEP's Jim Welsh helped identify one in the Pitt archives. Reclamation work will begin later this summer. About a quarter of CONSOL's hardback maps have been scanned so far, adding more than 53,000 acres to the DEP's database of areas that have been mined. The Office of Surface Mining provides similar information to the public for areas outside of the Pittsburgh region. For the Allegheny Front, I'm Leah Kauffman.