ABSTRACT
Tracer blasting is used in Canadian underground mines to minimize the overbreak in development headings. The miners feel much at ease with ANFO due to its safety and simplicity of loading. The lower cost and minimum overbreak makes it economically attractive to the mine management. This study has attempted to examine the application of tracer blasting during stoping operations. The field work was done at a Gold mine in Timmins, Ontario. The ANFO loaded holes in test rings were traced with a booster cord. The booster cord is different from a typical detonating cord and consists of a signal cord with bumps of higher core loads of PETN at equally spaced intervals.
There was a significant reduction in the explosive cost during ring blasting as compared to commonly used explosives in stoping operations. The peak particle velocity of ground vibrations was lowest in the case of tracer blasting as compared to the cartridged emulsion and ANFO. A reduction in the secondary breakage cost was observed during muck handling at different levels, which confirmed adequate fragmentation observed during visual examination of the muck pile.
