Minimum distances for drilling near explosives

(1) Drilling shall not be carried out within 300 mm (12 ins) of a bootleg hole on surface or within 150 mm (6 ins) underground unless a safe, acceptable procedure has been developed. No drilling in blasted rock (2) No person shall drill in loose rock produced by blasting unless the rock has been thoroughly examined to ensure that it does not contain explosives or an engineered pattern is utilized to prevent overlaying of new holes over previously blasted holes.