From the locked thread -
"We referred to it as a new tunnel because
First, EH's article in British Archaeology Jan 2005 [Appendix 5] said – "Atkinson's tunnel entrance would be re-opened and "a new tunnel constructed to the centre of the hill" "
From Britarch -
"Atkinson's tunnel entrance would be re-opened and a new tunnel constructed to the centre of the hill, <b>ideally wholly within the line of the original</b>. Then working outwards from the centre, the remaining collapse and infill material would be removed and all voids re-filled with properly compacted chalk."
http://www.britarch.ac.uk/ba/ba80/feat1.shtml
Prefer to leave certain information out do you Mr Swift?