Mineshafts near property - next steps

Hsmum42

Hi - wonder if anyone can help. We are looking to buy a property (60s bungalow) and have just had the searches back. They show there are two mine shafts, one within the grounds of the property. They are recorded to have been treated, but its unknown as to what standard this was. 

We are not quite sure what our next steps should be. We were planning to extend and remodel the existing property. Is this now even possible? I believe we can get further investigations done, but no idea as to what the cost and time frame of that would be. 

any advice would be gratefully received. 

thanks

ETA picture of site - green area is woodland belonging to the property that can not be developed which appears to be where shafts were.

Wren14

My house has 3 mineshafts within 10 metres, one of which is underneath my attached neighbours living room!
I can't offer any advice on if you can build over them now but the Coal Authority are really helpful and you get to speak to a real person when you phone them. Best to go direct to them and ask if they can be built over or not. 

Hsmum42

Thanks - we don’t want to build over them, just extent the footprint of the existing property which is away from where they have labelled the shafts x

daveyjp

Shafts lead to adits, knowing where they are and how deep - if the mines are old they may only be 3-5m under the surface - will need to be investigated if you plan to dig.