The cost is very close to Scheme Two and is therefore a viable alternative. Since this alternative requires no excavation, a problem in archaeological sensitive sites, it is the preferred alternative. The cost of archaeological monitoring and testing would make Scheme Two more costly. Only one scheme is proposed for this wall. The general treatment will be to pressure grout the wall and cracks.
Some additional strength is required at the points which cracked severely.
Structural plaster is proposed for the inside finish where shown on the drawing. This will be tied to the steel chords and into the rock with epoxy anchors at regular intervals. The general treatment should be sufficient to both repair and upgrade these walls to better lateral resistance. That will include pressure grouting the wall and the cracks. The building was recently rehabilitated as a visitors centre.