The Gruve 7 mine lies 15 kilometers from Longyearbyen and has been in production since 1975. About 20 people are employed in the mine, which produces approximately 70 000 tons of coal annually. Some 25 000 tons of this are delivered to Longyearbyen Energiverk, which is Norway’s only coal-fired power plant and provides electricity and heating in Longyearbyen. The rest of the coal is sold largely to foundry industry in Germany.
The coal seam in the Gruve 7 mine has an average thickness of 1.5 meters. Coal is mined using the room-and-pillar method, in which a network of ‘rooms’ is cut into the coal seam leaving behind ‘pillars’ of coal to support the roof of the mine. The coal is extracted by a Continuous Miner (CM), which is a crawler-mounted mining machine that can be remotely controlled. The coal is transported on conveyor belts out of the mountain and then onward by truck to Longyearbyen.