Highly Polluting Industries

**Thermal Power:** ~88% of annual industrial water consumption **Engineering:** ~5% of annual industrial water consumption **Paper & Pulp:** ~2.3% of annual industrial water consumption **Textiles:** ~2% of annual industrial water consumption Industrial water consumption does not include water consumption of agriculture sector.

In a steel furnace, coke reacts with iron ore , releasing iron and generating CO and CO2 gases. Due to the use of coal , pollutants such as SOx and NOx are released, therefore all are correct options.

**1. Copper slag** is a by-product generated during the extraction and refining of copper. It can be used as a partial replacement for sand in concrete production, thus reducing the demand for natural resources. This reduces the environmental impact associated with sand mining. **2. Cold mix asphalt technology** involves producing asphalt mixtures at lower temperatures compared to traditional hot mix asphalt. This results in reduced energy consumption during production and lower emissions of greenhouse gases. Cold mix asphalt also allows for the use of recycled materials, further enhancing its environmental sustainability. **3. Geotextiles** are synthetic materials used in road construction for various purposes such as soil stabilisation, drainage, and erosion control. They can help in reducing the need for excessive excavation and use of natural resources like stone and gravel, thereby minimizing environmental impact. **4. Hot mix asphalt technology** involves producing asphalt mixtures at high temperatures. While it provides excellent performance properties for roads, it typically requires higher energy consumption during production compared to cold mix asphalt technology. **5. Portland cement** is a key ingredient in concrete production. While it is widely used in construction, its production process is energy-intensive and emits significant amounts of carbon dioxide, contributing to greenhouse gas emissions. Therefore, the correct answer is A. 1, 2, and 3 only.

**Statement 1 is correct.** Furnace oil is indeed a product of oil refineries. It is a dark viscous residual fuel obtained by blending heavier components of crude oil. **Statement 2 is correct.** Furnace oil is widely used in industries like cement, steel, and textiles for power generation and heating. It is burned in boilers, furnaces, and engines to produce energy. **Statement 3 is correct.** Furnace oil contains high sulfur content, and its combustion releases sulfur oxides (SOₓ), contributing to air pollution and acid rain.

* **Statement 1 is correct:** Gold mining is poisoning Amazon forests with mercury. To separate the gold, miners mix liquid mercury into the sediment, which forms a coating around the gold. * **Statement 2 is correct:** Fly ash generated by TPPs is one of the ways mercury is released into the environment. Fly ash is usually disposed of in ash ponds in the form of ash slurry, forming an aquatic ecosystem of its own. Coal-based TPPs are the major source of mercury – the ninth most toxic element found on earth — emissions into the environment. Mercury contributed over 80 percent of emissions released by the TPPs, according to 2016 estimates by the Delhi-based think-tank Centre for Science and Environment. * **Statement 3 is incorrect:** While mercury is unquestionably toxic, toxicology works on the principle of dose: “The dose makes the poison.” Hence, scientific bodies define **reference doses** (RfD) or tolerable intake levels, not zero exposure. WHO's Provisional Tolerable Weekly Intake (PTWI) for methylmercury (from fish) → 1.6 µg/kg body weight/week and 1 µg/litre for total mercury in drinking water. If no safe level truly existed: Mercury would be completely banned, not regulated. **NOTE:** UPSC usually considers extreme statement to be wrong.