The hoist shaft at Mökkivaara was completed in 1939. It was needed in addition to the old shaft to increase annual production. In addition to ore extraction, the shaft was used for the transport of people and goods.

Once the Keretti facilities were completed in 1954, all ore hoisting happened there. The hoisting of personnel, goods, and surrounding rocks was left at Mökkivaara.

With the mechanization of mining equipment in the 1960s, large loaders and drilling jumbos came into use. Now that it was possible to move freely in inclined tunnels, creating an inclined tunnel connection to the surface became even more important.

The three-kilometer-long Kaasila inclined tunnel was completed in 1973. Now, transporting goods to the mine could be done thru the inclined tunnel. Passenger traffic was centralized to the Keretti shaft, which had a separate passenger lift. This was different from Mökkivaara, where there was only one crane for surrounding rocks and personnel hoisting. The mine's tunnel network had expanded so that personnel transport underground was carried out by wheeled vehicles from the Keretti shaft to the Mökkivaara mining areas.

The shaft at Mökkivaara became unnecessary. The elevator car and hoist bucket were removed from the shaft. New fans were installed there, and the shaft was converted into a fresh air ventilation shaft.