Two caverns 20m-wide x 190m-long x 33m-high in phyllite, rockbolted and shotcreted. Total excavation 250,000m3. Contract includes 4km of 30m2 section cooling water tunnel and 1km of 65m2 section road tunnel. Contractor: AF Spesialprosjekt using Atlas Copco Rocket Boomer 353 rigs with COP 1838 drills, one with extended reach. Bever controls for contouring. Caverns excavated on three benches with two faces at each level. 1,200m3 blasted in each round. Completion end-1998. Dec 1998.
