Ohio, West Virginia and Pennsylvania. You can also type a latitude and longitude, like 40.0804, -80.9009, or paste the link to a home for sale from Zillow, Realtor.com, Redfin or a local broker's site: the page reads the address out of the link itself and never opens the listing. As you type, the letters go to Esri's address search for suggestions; the address you pick goes to the US Census Bureau or Esri to find it on a map, and the point goes to the state and federal map services listed at the bottom of this page. I get a note that the tool was used, with the town and the answer, never the street address. If you ask for the PDF by email, I also get the email you typed. Nothing else is saved, except the compare list if you make one: it stays in your own browser, on your device, and I never see it.
Before you buy / mine check --
A mile around the address.
0 mapped mines within a mile
Two miles across, north at the top.
Print a one-page summary
Print the full report
Check another house
The share picture says what is under your house and never shows the address.
Owning or buying near old mines: the longer guide
Over a mapped mine is not the same as a problem. Most houses over old mines never move. When the ground does settle it is expensive, and what pays for it depends on your state and county; the insurance part of this report has the rules for this address. What to do depends on where you stand.
I am buying
I own the house
I am building
Run the address before you make an offer. Some sales come with no seller disclosure form at all, such as court-ordered sales, foreclosures and many estate sales, so nobody may bring the mine up but you.Ask the state for the mine map of that spot. It shows how deep the coal was and how it was mined, which this page cannot. Who to ask is in the What to do part of this report.Ask the seller in writing about any cracks, repairs, settling or mine subsidence claims on the house, even if the disclosure form does not ask.Ask your title company about the coal. In coal country the coal under a lot is often sold separately from the surface, and an old deed can give up the right to have the ground held up. Ask for a search that goes back far enough to find that, and ask what the title policy leaves out about minerals and settling.Many buyers put the inspection and an insurance quote in their contingencies ; ask your agent or attorney. Ask the home inspector to note any cracks, and get the mine subsidence coverage priced before closing, not after.Over a mine with a state permit? A permit can stay open long after the mining stops, so ask the state whether anything is planned. Ask the mine company for its mining plan for the property. Longwall mining is planned to let the ground settle, and some states require the company to repair or pay for the damage.
Find out what your mine subsidence coverage pays. The insurance part of this report has the rules for your county; check your policy papers for the line and its limit.Learn the signs and look once a season. New cracks that step up a block or brick wall, doors and windows that start to stick, floors that tilt, a dip or a hole in the yard, pipes that break for no reason.If you see them, talk to a licensed professional engineer who has worked on mine subsidence before you call a contractor, and take dated photos of every crack. The numbers to call are in the What to do part of this report.Smell gas in the basement, or water coming in that never did before? Over old mines, mine gas and mine water can find their way into a basement. For gas, get out and call 911 from outside. Then report it to your state’s abandoned mine program.Report a sinkhole or sudden settling to your state’s abandoned mine program. Ohio, West Virginia and Pennsylvania all investigate, and their programs can fill a void under private land.
Get the mine map before you buy the lot. Depth matters most: a shallow mine under a new foundation is the case engineers worry about.Have a geotechnical engineer look at the site. Over a shallow mine they may drill to find the voids and fill them with grout before anything is built.Ask about the foundation. A design for possible settling costs far less on paper than a repair later.Ask about mine subsidence coverage when you insure the house. In West Virginia it starts 30 days after you apply; in Pennsylvania the state policy starts when you apply and pay.
How these mines were worked
Room and pillar. Most of the old mines here were dug as rooms with pillars of coal left standing to hold the roof up. Over decades the pillars and the roof can weaken, and the ground above can sag years after the mine closed. Whether the pillars were left or pulled is the question to ask about any mine under a house.
Pulling pillars. Many mines took the pillars out on the way out of a section, called retreat mining or pillar robbing by miners. That gets more coal and leaves less holding the roof, so the ground over those sections usually settles sooner and more. The state mine map often shows where it was done.
Longwall. Today’s big mines take a whole panel of coal at once with a longwall machine. The ground over a panel is expected to settle as the machine passes, mostly within months. If a working longwall mine is near, ask the company for its plan and timing under the property before it gets there.
Strip mines. Surface mines were dug from the top and filled back in. The fill can settle on its own for years.
Where the answer comes from
Everything is read live from public map services each time you check, nothing is copied or kept:
Ohio: the Ohio Department of Natural Resources’ Abandoned Underground Mines maps, the Division of Mineral Resources Management’s permit records for mines worked since 1977, and the Division of Oil and Gas well records. Whether a permitted Ohio mine is still producing comes from the federal Mine Safety and Health Administration’s mine records, refreshed by hand at least every 45 days.West Virginia: the West Virginia Geological and Economic Survey’s mined-area maps and the Department of Environmental Protection’s underground mining permit limits.Pennsylvania: the Department of Environmental Protection’s mined-out areas, underground mining permits, longwall panels, mine shafts and its mine subsidence insurance map.Everywhere: FEMA’s National Flood Hazard Layer, US Census Bureau address lookup, and USGS The National Map for the terrain, map and satellite views, the road and place names and the landmarks. The 3D fly-over’s roads and town names come from OpenStreetMap, served by OpenFreeMap.
It is approximate and it is not a guarantee either way. The outlines come from old mine maps, some of them a hundred years old, and some mines were never mapped at all. “No mapped mine” does not mean there is no mine. “Over a mine” does not mean the ground will move. A state permit can stay open years after a mine closes, so a permit alone never means mining is going on. This is a place to start, not an inspection, an engineering opinion or legal advice.
I am Blake Porterfield, and I built this in St. Clairsville because people around here kept asking. It is free and it stays free. Willow Creek builds tools like this for local businesses: (740) 310-9000 .