Drilling shall not be done in or within what distance of old holes or bootlegs?

• A. 5 centimeters
• B. 10 centimeters
• C. 15 centimeters
• D. 20 centimeters

Answer: (C)

Maintaining a safe clearance from old holes or bootlegs is about preventing unintended communication with existing voids and gas pathways. Old holes can connect to methane pockets, ventilation routes, or unstable rock around them, so drilling too close could intersect the void or create a conduit for gas, dust, or a blowout. A minimum distance of 15 centimeters provides a margin for drill deviation and irregularities at the opening, reducing these risks. Distances smaller than that leave too little clearance, while a much larger distance isn’t required by the rule and would unnecessarily constrain work. So the recommended distance is 15 centimeters.