Thanks Trev for your comments,
The site I am interested in is directly over a mined 5m coal seam less than 25 meters below the surface. The mine closed in 1960, There also appears to be a fairly large amount of “fill” on the land left from the mining activity.
My project would involve building up to 4 houses and selling at 2 or 3 on completion. I am most concerned about the degree resistance potential buyers might have to buying property on such land. Do banks worry about lending for such properties and are there any ongoing insurance issues?
Also would there be any lasting liability that I (as the developer) might have if a sink hole should appear and damage a house that I sold.