Abstract: A mobile platform in an underground mine supports an electric motor that operates a compressor to supply air under pressure to one or more hoppers containing abrasive particles which are held in suspension and pressurized within the hopper. The electric motor is drivingly connected to a hydraulic pump that supplies water under pressure in a range of 3000 to 4000 p.s.i. through a conduit to the water inlet of a nozzle assembly. A second conduit conveys the pressurized abrasive particles to the nozzle assembly for admixture with the water. The flow of abrasive particles is maintained by the compressed air at a constant flow rate to enhance the output velocity of the water encapsulated particles from the nozzle assembly. The abrasive stream impinges on the surface of a gas well casing to sever the casing as the nozzle assembly is rotated around the casing. In this manner a pipe or gas well casing obstructing a mining operation is removed without generating sparks in the hazardous mine atmosphere.