Geological mapping, rock mass classifications, regional mapping, slope stability analyses and supports of the excavation of drill & blast tunnelling in hydropower project, site geological & geotechnical investigation, monitoring and interpretation data, drill core logging, outcrop logging, gallery and tunnel logging, etc. Tunnel construction and supervising, underground rock evaluation and assessment, classification of rocks. PRD (Permanent Rock Support Design) at the Devoll hydropower project in Albania. PRD is a Sweco branch in Albania that at work peak consisted of 6 expats + 7 locals. The PRD team duties s and has been to design all the permanent rock support at the drill and blast parts of the tunnels and caverns in the project. This includes to continuously, after every blast, make a geological mapping and adjust the rock support design to local conditions and to evaluate the contractors suggested initial support. It also includes precision convergence measurements with tape extensometers. In total around 10 km of tunnels with areas between 30 m2 to 45 m2 was excavated in very different rock types and rock qualities. The rock types encountered spanned from strong to weak conglomerate high up in the tunnel system moving towards flysch (sand- silt- and claystones) of very varying quality further down the tunnel system and finally a transition to harzburgite of very varying quality at the lowest part of the tunnel system. In addition, two caverns were constructed in a harzburgite of generally poor quality, one main power house cavern 60 m long, 16 m wide and 35 m high and one transformer cavern 26 m long, 16 m wide and 20 m high.