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 ?
- (a) 1 only
- (b) 2 and 3 only
- (c) 3 only
- (d) 1, 2 and 3 ✓ UPSC's answer
Why the answer is (d)
• Statement 1 is correct: coal ash (fly ash and bottom ash) concentrates heavy metals such as arsenic, lead, mercury and cadmium.
• Statement 2 is correct: burning coal releases SO2 and NOx, the precursors of acid rain and smog; India set emission norms for power plants in 2015.
• Statement 3 is correct: Indian coal is high-ash (35–45%) but low-sulphur, which is why India generates about 200 million tonnes of fly ash a year.
• Hence 1, 2 and 3, option (d).
Why the other options are wrong
- (a) 1 only
- Statements 2 and 3 are also correct.
- (b) 2 and 3 only
- Statement 1 on heavy metals in coal ash is also correct.
- (c) 3 only
- Statements 1 and 2 are also correct.
Asked in the GS Paper I of the UPSC Civil Services Preliminary Examination 2020, held on 4 October 2020. Question and answer key: Union Public Service Commission. Explanation: UPSC Answer Check.