Combe Down, Bath
In 1988-89 open-cast quarries and shallow stone mines at The Brow were investigated by trenching and rock probing for several large detached houses. Successful stabilisation was achieved by jack-hammering out the thin roof cover, crushing the rocky spoil and consolidating with vibro-replacement stone columns. Raft foundations were subsequently adopted.
Ref: GG Thomas (1987) Cost Benefit Analysis for Stabilising Shallow Bath Stone Mines.