Question

UPSC Prelims 2020 Question:

Consider the following statements:

  1. Coal ash contains arsenic, lead and mercury. 
  2. Coal-fired power plants release sulphur dioxide and oxides of nitrogen into the environment. 
  3. High ash content is observed in Indian coal.

Which of the statements given above is/are correct?

  1. 1. 1 only
  2. 2. 2 and 3 only
  3. 3. 3 only
  4. 4. 1, 2 and 3

Answer (Detailed Solution Below)

Option 4: 1, 2 and 3

Detailed Solution

Explanation:

  • Contaminants in coal ash include mercury, cadmium, lead, chromium, selenium and arsenic. These contaminants, if not properly managed, can pollute waterways, ground water, drinking water, and the air. So, statement 1 is correct.

  • Coal combustion emits numerous pollutants, including nitrogen oxides (NOx) and sulphur oxides, as well as particulate matter. They also emit greenhouse gases like carbon dioxide and methane, both of which have been linked to global warming and climate change. So, statement 2 is correct.

  • According to Coal India Limited, the ash content of domestic coal ranges from 25 to 45%, whereas the ash content of imported coal ranges from 10 to 20%. Because of the drift theory of coal deposit formation in India, Indian coal has a higher ash content than imported coal. So, statement 3 is correct.

Therefore, option (4) is the correct answer.

Subject: Environment | Pollution

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