Drilling of vertical shafts for ONKALO complete
All vertical shafts of the underground research facility ONKALO have now been drilled through. The last of the shafts to be drilled was the personnel shaft, with the final phase being completed in early April.
The inlet air shaft and personnel shaft reach the depth of 455 metres, while the exhaust air shaft reaches 437 metres.
The reinforcement of the personnel shaft and the partial reinforcement of both air shafts will begin in the latter half of this year.
The maintenance and hoisting cage will be removed from the exhaust air shaft and installed to its proper position in the inlet air shaft. The exhaust air shaft will then be modified to fulfil its actual purpose, with exhaust air from ONKALO routed to flow via the designated route.