Its a current project of mine.
Apprently as well as having underground stables it was also worked on 2 levels and coverd an extensive area extending under a major A road.
A small side working does exsist, howevwe its tiny and ends in stacked deads with little to no crawlspace.
http://www.aditnow.co.uk/photo/Windrush-Sandstone-Quarry-User-Album-Image-001/ Having walked the area extensivley in the winter and seeing a large depression in a field some distance from the main workings, the above ground evedence would certainly support the written word.
I've done a couple of visits to the area, last time was not so long back with sloworm, j and the walrus (who journaled the day over on DP).
There are other "Interesting" features along the way to look at, so i'm going to be a bit twichy about its eaxct location atm, just incase it all goes to cock.
Better to regret something you have done - than to regret something you have not done.