● Coal ash, a catchall term for several kinds of waste left over at power plants that burn coal, typically contains a number of substances harmful to human health—arsenic, chromium, lead, and mercury among them. Hence Statement 1 is correct.
● Pollution from coal-fired power plants comes from the emission of gases such as carbon dioxide, nitrogen oxides, and sulfur dioxide into the air, as well a significant volume of wastewater which may contain lead, mercury, cadmium and chromium, as well as arsenic, selenium and nitrogen compounds. Hence Statement 2 is correct.
● Coal India Limited announced that ash content of coal produced in the country is generally 25 to 45 % whereas average ash content of imported coal varies from 10 to 20 %. Indian Coal has comparatively higher ash content th solar water pumps, consider an imported coal due to drift theory of formation of coal deposits in India. Hence Statement 3 is correct.