The higher horizon adits draining show all is not well.
I have a hunch that it's probably going to be a wet and collapsey experience.
If you are wandering the fields, I have yet to have a look at these. ~
http://www.flashearth.com/?lat=50.257013&lon=-5.110461&z=17.4&r=4&src=msl
Went out there today, took a few photos. Not a lot to see, sadly. But here you go:
http://imgur.com/a/95Azw#5 [1-2] Mitchell shaft, hadn't snapped that one yet ;)
Triangular shaped wooded bit south of road, east of houses: a capped shaft well hidden (you can't see it from the road).
[3-6] Just SW of cursor, in field: a large mound, with gorse on top. No sign of a shaft, if there is one it is buried.
[7-10] Pointy extrusion from hedge just NE of cursor: a capped shaft, well hidden in gorse and brambles. Not visible until you're on top of it.
[11-13] Mound in next field, NE of 1st field: a large mound, flat on top, overgrown completely. No sign of a shaft or cap, but could be one under the vegetation.
[14-16] In next field, NE, at bend in dirt track: a large triangular mound, covered in stones. No sign of a shaft.