They have been going on about it for some time. It was used by some local people as some sort of garden and the engine house was within the site. I gather the shaft is slabbed over and has a vent pipe. I could not find this. If it was allowed to vent, it would improve the quality of air underground which is shocking.
Lord Falmouth has been threatening to do something spectacular with the site for years, from an airport, golf club to loads of new homes. Since Hallenbeagle has been developed (the other side from killifreth) it probably sets some sort of precedent to do something with the land, whilst the planners are feeling all lovely about the fantastic industrial estate they have made.
There are A LOT of shafts on the site. Lots more than you can see metal cones for. At some point they will ****** it up.