the bombs are used to intentionally start slides in areas that are likely to slide. if the start it with a bomb and use the proper safety measures, no one gets hurt. if they open it to the public and the avy is triggered by an unsuspecting skier then death could result. also, in some places, bombs are used above roadways so that a natural avy does not take out traffic. and by dropping bombs they literally mean they have bombs that they will throw over cornices into specific locations. its also comon to run bombs out on cables in hard to reach chutes, these bombs can also be shot across canyons to reach those far off slide paths (Alta)hope this clears things up