Read the passage and answer the questions:
Methods of Mining
The discovery of minerals in the history of human development, is reflected in many stages in terms of copper age, bronze age and iron age. The use of minerals in ancient times was largely confined to the making of tools, utensils and weapons. The actual development of mining began with the industrial revolution and its importance is continuously increasing. Depending on the mode of occurrence and the nature of the ore, mining is of two types: surface and underground mining. The surface mining also known as open-cast mining is the easiest and the cheapest way of mining minerals that occur close to the surface. Overhead costs such as safety precautions and equipment is relatively low in this method. The output is both large and rapid. When the ore lies deep below the surface, underground mining method or 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. Have you ever read about mine fires and flooding of coal mines in India? The developed economies are retreating from mining, processing and refining stages of production due to high labour costs, while the developing countries with large labour force and striving for higher standard of living are becoming more important. Several countries of Africa and few of south America and Asia have over fifty per cent of the earnings from minerals alone.
Which of the following is the main feature of underground mining method?
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → This method requires specially designed lifts, drills, haulage vehicles and ventilation for safety.
Option (1) It is known as open-cast mining. — Incorrect. Open-cast is the other name of surface mining; underground mining is the shaft method.
Option (2) This method requires specially designed lifts, drills, haulage vehicles and ventilation for safety. — Correct. When the ore lies deep, vertical shafts are sunk and underground galleries radiate to reach the minerals. Moving people and material through these passages needs specially designed lifts, drills, haulage vehicles and a ventilation system.
Option (3) There are very low safety precautions and equipments used in it. — Incorrect. Low safety costs belong to surface mining; underground work needs special safety equipment.
Option (4) It is the cheapest way of mining. — Incorrect. Shafts, galleries, lifts and ventilation make underground mining costly; surface mining is the cheapest.
Note: This passage is taken almost word for word from the NCERT chapter ‘Primary Activities’ (Fundamentals of Human Geography): the opening lines on minerals in the history of human development and the section ‘Methods of Mining’. NTA did not dig far for this passage: it came straight from the book’s ‘Methods of Mining’ page. One slow look at Fig. 4.19 there, and shaft and open-cast mining will never confuse you again.
NCERT (2025-26): “Methods of Mining … Depending on the mode of occurrence and the nature of the ore, mining is of two types: surface and underground mining. The surface mining also known as open-cast mining is the easiest and the cheapest way of mining minerals that occur close to the surface. Overhead costs such as safety precautions and equipment is relatively low in this method. The output is both large and rapid.…” “Methods of Mining … 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. Have you ever read about mine fires and flooding of coal mines in India?…”
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