A method of blasting rock at an underground blast site in which boreholes aredrilled in arock mass from a drive defining face, each borehole is loaded with at leastone charge ofexplosive material, at least one detonator is placed in operative associationwith eachcharge, and a sequence of at least two initiation events is conducted to blastthe rock mass,in each of which only some of the charges are initiated, by sending firingsignals to onlythe detonators associated with said charges and in which each initiation eventis a discreteuser-controlled initiation event. In one of the at least two initiation eventsa strandedportion of the rock mass such as a pillar is created that has already beendrilled andcharged, and the stranded portion of the rock mass is blasted in a subsequentone or moreof the at least two initiation events without personnel accessing saidstranded portion. Firstexplosive charges may be blasted in the one initiation event, leaving a pillarof strandedore with the preloaded borehole extending through it. The detonators may bewireless.
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