Shaft excavation down to elevation 152, removing material by
access gallery in elevation 152 (T6).Estimated volume: 158 m3
4th Stage
Staggering benching from elevation 164.60 down to 158 and 152,
removing material by shaft andaccess gallery at elevation 152
(T6).Estimated volume: 23970 m3
5th Stage
Shaft excavation down to elevation 132, removing material by
draft tube and tailrace tunnel.Estimated volume: 231 m3
6th Stage
Staggering benching from elevation 152 down to 145, 138 and 132,
removing material by draft tube,shaft and tailrace tunnel.Estimated
volume: 21725 m3
7th Stage
Benching of the base of the chamber removing material by draft
tube and tailrace tunnel.Estimated volume: 1100 m3
