Which of the following is true of underground mining method?

When the ore lies deep below the surface, underground mining method is used. It is also called Shaft Method. It requires specially designed lifts, drills, haulage vehicles, ventilation system for safety and efficient movement of people and material. Hence this process is risky. All of the above

All of the above

When the ore lies deep below the surface, underground mining method (shaft method) has to be used. In this method, vertical shafts have to be sunk, from where underground galleries radiate to reach the minerals. Minerals are extracted and transported to the surface through these passages. It requires specially designed lifts, drills, haulage vehicles, ventilation system for safety and efficient movement of people and material. This method is risky. Poisonous gases, fires, floods and caving in lead to fatal accidents.