Julian Cope presents Head Heritage

In the first half of the tunnel the voiding is said to be no more than 0.5 metres above Atkinson’s steel support arches. However, in two sections this voiding is said to be directly associated with the visible surface slumping uphill from the entrance, which is clearly a lot more than 0.5 metres higher, suggesting (to me at least) that the height of the voiding is only a small part of the story and that the damage and loss of integrity extends in a column above it right to the surface...