DISCUSSIDN ON OVERCOMING THE LARGE TOE BURDEN BY THERMAL BLAST-HOLE CHAMBERING IN NANFEN OPEN-PIT MINE

This article introduas tha due to the long toe burder and the smaller angle of foowall benches for thesmaller angle (40°～50°) of seams in Nanfen pen-pit Mine. Por this, author recommendes the successfulexperiences with thermal chambering of blast holos in Russia for overcondng the tightbottoms by increasingexplodve charge and without deepening the ovetdrill. By this method the productivity will be increaed andthe cest cut will be achived also.