Concerns are in the press today that the proposed new flyover near Blick Mead could obliterate the ancient and fascinating site. - see Arianna Huffington's Weblog for example.
The Highways Agency has been criticised for circulating an inaccurately labelled plan of their proposal.
This is the plan (sans labels) and the Google view of the existing junction. It appears that the proposed junction footprint is within the existing road area. The worries over the effect on the water table, the construction process and the raised height of the road are all matters of concern.
Click to enlarge
The proposals are to be discussed at a series of meetings in the next few months. Your views will be welcomed.