UNDERGROUND PROTECTION UNDERNEATH A DUMP

摘要

A dump sitting on the ground is isolated by first driving a tunnel longitudinally through the ground underneath the dump, then cutting from at least one side of the tunnel with a longwall-mining machine a longitudinally and transversely extending slit having a lower end opening into the tunnel and an upper end opening at ground level, and providing a liquid barrier in the slit underneath the dump. The material dug by the machine to form the slit is first conveyed downward along the slit into the tunnel and thence along and out of the tunnel. Stowing material is brought into the slit from the upper end thereof to backfill behind the machine. The cutting machine itself can be a standard cutter head with a longwall conveyor and a set of following props that hold up the roof behind the cutter until this area is backfilled.