Had another look at this plan. The tip before removal, indeed stretched from below the entrance of the Firestone(Rampgill)to around the entrance of Smallcleugh, roughly 300m.
Paradoxically it was not the largest tips removed, these were above the Firstone, stretching up the hill, across the road, following the course of Rampgill Vein.
Presumably, after removal, is what we see today, namely the cut around the stream.