Loading of boreholes with flowable explosives

A method of loading a flowable explosive into a borehole which includes, in a single operation, feeding the flowable explosive, or its constituents, and the flowable stemming material, or its constituents, successively into the borehole, by the steps of:

• inserting a lance into a mouth of the borehole until an outlet end of the lance is adjacent a blind end of the borehole;
• feeding the flowable explosive, or its constituents, into the borehole along a conduit of the lance;
• withdrawing the lance from the borehole as the borehole receives flowable explosive, or its constituents, from the outlet end of the lance, the withdrawal and feeding being at rates which are synchronized with each other so that the volume of the borehole between said outlet end of the lance and the blind end of the borehole corresponds with the volume of flowable explosive, or its constituents, which has been fed into the borehole;
• inserting a plug of the flowable stemming material into the borehole, when the flowable explosive, or its constituents, has been loaded, by feeding the flowable stemming material, or its constituents, into the borehole along another conduit of the lance;
• withdrawing the lance further from the borehole, as the borehole receives the flowable stemming material, or its constituents, the further withdrawal and the feeding of the flowable stemming material being at rates which are synchronized with each other so that the volume of the borehole between said outlet end of the lance and the flowable explosive in the borehole corresponds with the volume of the flowable stemming material, or its constituents, which has been fed into the borehole;
• and
• causing or allowing the flowable stemming material, or its constituents, to set, so that it forms a non-flowable plug which closes off the borehole by engaging the wall of the borehole, thereby to stem the flowable explosive in the borehole.