Start here
The short answer
There are three places to look, and the first two are free. Search your address on our map to see what the old records hold near you. Ask your state mine map office for the mine map itself, which is the only document that shows where the rooms and tunnels actually run. If anything on your ground is already moving, that is not a records question and it comes first: call the state emergency number on your state page, and 911 if anyone could fall in.
Nobody can tell you from a map alone that your house is safe. What you can do, in an afternoon and for nothing, is find out whether anyone ever dug under your part of town and who holds the drawing of it.
Free, no sign up
Start with the free map
Our search takes a street address, a ZIP code or a town and draws every old mine record within the distance you choose, nearest first. It covers every state and Puerto Rico, it is free, and it asks you for nothing.
What comes back is a list of recorded workings with what was dug, how far the site got, and whether it was worked at the surface or underground. An underground opening is the one that matters most to a house: it is a way into workings that carry on out of sight.
Plain limits
What the map can tell you, and what it cannot
It can tell you that a shaft, a tunnel or a pit was recorded near your address, what came out of it, and roughly where it is. That is often the first anyone in a household has heard of it.
It cannot tell you that a working runs under your garden. A record is a point on a map, not a property line, and the two national files only hold a working where somebody catalogued it or drew it on a survey sheet. Plenty was never drawn at all, especially coal. Finding nothing on our map is not a clearance.
The document itself
Then ask the office that keeps the mine map
Every state has an office that holds the mine maps for its own ground, and your state page names it with its address, its telephone number and what it will send you. Most of them answer a plain request from a homeowner, and most charge nothing or little more than copying.
Two states let you check an address yourself. Pennsylvania publishes an undermined area check at the DEP mine subsidence risk viewer, and Ohio has a mine locator map at the Ohio Department of Natural Resources. Everywhere else it is a request by email, by form or by telephone.
If your state cannot find the map, the federal collection can. The National Mine Map Repository in Pittsburgh holds the national archive of closed and abandoned mine maps, more than 275,000 of them, and will search it for you by state, county, company or mine name.
What you get
What a mine map actually shows
| On the map | What it is | Why it matters |
|---|---|---|
| The outline of the workings | The rooms, the tunnels and how far they reach from the opening | This is the part a point on any map cannot give you |
| The depth | How far below the surface the working sits | A working a few feet down behaves very differently from one hundreds of feet down |
| The seam or the vein | Which layer was taken out, and how thick it was | It tells an engineer how much ground was removed |
| The pillars | The blocks left standing to hold the roof up | Pillars left out, or taken later, are the usual reason old ground gives way |
| The date it was certified | The day the map was signed off as a true record of the workings | Anything dug after that date is not on it |
| What is missing | Workings nobody mapped, and maps nobody kept | An old mine with no surviving map is common, and the office will tell you so |
Before you sign
If you are buying a house
- Step 1. Search the address on our mapIt takes a minute and it is free, and it tells you whether this is a question at all in that town.
- Step 2. Ask your state mine map office in writingAsk for any mine map covering the parcel and the area around it, and keep the answer, including an answer that says there is nothing.
- Step 3. Ask the seller and the agent what they knowAsk the question plainly and in writing, and ask whether the house has ever been repaired for ground movement.
- Step 4. Put it in the inspectionTell the inspector what you found and ask for the walls, the floors, the drive and the doors to be looked at with that in mind.
- Step 5. Ask about cover before you need itIn eight states there is a separate mine subsidence policy, because a normal home policy usually does not pay for a mine collapse. Your state page says whether yours is one of them.
First, not last
If the ground is already moving
Doors and windows that stop closing, a crack that runs at an angle across a wall, a floor or a drive that dips, a sudden wet patch or a well that goes dry: those are worth reporting the day you see them, not after a holiday.
Call your state abandoned mine programme, which your state page names with its number, and call 911 first if a hole is open or anyone could fall in. Measure what you can see, write the date on it and keep measuring, because how fast it grows is the first thing an engineer will ask.
No jargon
The words you will run into
Adit, portal, overburden, subsidence, room and pillar: the offices use these words and so do their forms. Every one of them is explained in one plain line on our words explained page, so you can read a letter from a state office without looking anything up.
Your own state
The office that holds the mine map, state by state
Each page names that state's own offices, its own counties and its own numbers.
Please read
Before you rely on any of this
The mine information here is for general information only. Old mine records can be incomplete, outdated or wrong, and finding nothing here does not mean there is nothing there. Check with the mine map office named here before you rely on it, and have a qualified engineer look at any ground you are worried about. PublicRecordCenter.com assumes no responsibility or liability for any errors, omissions, or consequences arising from the use of this information.