Yes. I've been looking at Orion's Belt, out the window, and am trying to reconcile it with the shape of the Thornborough henges. There is a striking similarity. There must be one hell of a heap of bones somewhere - from the feasting if not from the building. It's still rich agricultural land.
It's not far away in time from when the amphibians return to the pools to mate and spawn. While you have cited PPG9 in defense of Thornborough PPG16 is much stronger. (Let's hope I've got the numbers correct). If a survey found Great crested newt in the ponds - and the creatures do favour gravel pits - then there would be a whole new line of objection raised. Surveying by torch light, usually in April, has been deemed not to need a special license from English Nature.