When meeting with a large boulder, especially if it lies on soft rocks, explosive work is used — torpedoing, with which a large boulder is crushed into small parts, which are then extracted with a bastard. Torpedoing is as follows: the well is cleaned of the dirt and a small hole is poured out in the boulder; casing pipes rise 2-3 m above the slaughter, after which an explosive charge is lowered into the well.