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PART A: Control of Industrial Pollution
Filters · ESP · Inertial Collectors · Scrubbers · FGD · Catalytic Converters · Pollution Index · Coal Gasification
💡 Think of Industrial Pollution Control As a Multi-Stage Security Check for Air
Just like an airport has multiple security checkpoints — baggage scanner, body scan, manual check — industrial chimneys use multiple pollution control devices in sequence. Coarse particles are caught first (inertial collectors / filters), then fine particles (ESPs), then gaseous pollutants (scrubbers). The combination can remove 99%+ of particulate matter and most harmful gases. The problem: these devices cost money to install and maintain — which is why India’s thermal power plants have been delaying FGD installation for a decade.
The 6 Key Industrial Pollution Control Technologies
🔲
Filters (Baghouse)
PM Removal · Physical barrier
HowPolluted gas passed through fabric filter (like a giant vacuum cleaner bag) → particles trapped on filter surface
MaterialCotton/synthetic fabric for low temperatures | Glass cloth for high temperatures (up to 290°C)
RemovesParticulate Matter — both coarse (PM10) and fine (PM2.5) particles. Used in cement plants, coal plants, steel mills.
AdvantageSimple, effective for dry particles. Baghouse systems can achieve 99%+ PM removal. Low energy consumption.
LimitationCannot remove gaseous pollutants (SO₂, NOₓ). Filters must be cleaned/replaced regularly.
⚡
Electrostatic Precipitator (ESP)
Star Technology · 99%+ PM Removal
HowDust-laden gas passes between high-voltage electrode wires (thousands of volts) → corona discharge ionises particles → charged particles attracted to oppositely charged collecting plates → collected on plates → periodically knocked off
EfficiencyCan remove over 99% of particulate matter from exhaust gas — one of the most effective PM removal technologies
Used inThermal power plants (most critical), cement industry, steel plants, paper mills
AdvantageHigh efficiency even for very fine particles. Low flow restriction. Can handle very large gas volumes. Fly ash collected can be reused (cement, bricks).
LimitationCannot remove gaseous pollutants. High capital cost. Effectiveness reduces if fly ash has high electrical resistivity. Does NOT remove SO₂.
UPSCStandard equipment in all coal-fired thermal power plants in India. FGD required additionally for SO₂.
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Inertial Collectors (Cyclone Separator)
Pre-cleaner · Coarse PM removal
HowGas spun in a spiral inside a cone-shaped cylinder → heavier particles thrown outward by centrifugal force → particles slide down walls → collected at bottom. Cleaned gas exits from top.
RemovesCoarse particulate matter (PM > 10 µm). Used as first-stage pre-cleaner before ESP or baghouse.
AdvantageNo moving parts → very low maintenance. Handles hot, sticky gases. Relatively cheap. Works well for large particles.
LimitationPoor efficiency for fine particles (PM2.5). Cannot remove gases. Usually used in combination with other devices.
💧
Scrubbers (Wet + FGD)
Removes Gases + PM · FGD crisis in India
How (Wet)Polluted gas stream brought into contact with scrubbing liquid (usually water) → particles and soluble gases are absorbed by liquid → cleaned gas exits. Like mucus in the trachea trapping dust.
How (FGD)Flue Gas Desulphurisation (FGD): Uses limestone/lime slurry to absorb SO₂. Reaction: SO₂ + CaCO₃ → gypsum (CaSO₄·2H₂O) — commercially useful by-product.
RemovesBoth particulate matter AND gaseous pollutants (SO₂, HCl, HF). FGD specifically targets SO₂.
By-productFGD produces gypsum → used in cement, construction, wallboard manufacturing (circular economy)
LimitationGenerates liquid waste that needs treatment. High cost. FGD installation cost: ~₹1.2 crore/MW
💎
Catalytic Converter
Vehicles · Converts toxic gases
HowExhaust gases pass over catalysts (platinum, palladium, rhodium) → chemical reactions convert pollutants to harmless gases
Converts
CO → CO₂ | NOₓ → N₂ + O₂ | Unburnt HC → CO₂ + H₂OCritical ruleONLY UNLEADED PETROL must be used — lead poisons the catalyst permanently. India banned leaded petrol in 2000.
UPSC keyMandatory in all BS-VI vehicles. Platinum-group metals = expensive → vehicle cost. BS-VI SCR (Selective Catalytic Reduction) additionally reduces NOₓ using urea.
🔥
Coal Gasification
Cleaner coal use · Syngas production
WhatConverting solid coal into syngas (synthesis gas — mainly CO + H₂) by reacting coal with steam and oxygen at high temperatures. Then burning clean syngas instead of coal directly.
Why cleanerSO₂, NOₓ, and particulates can be removed from syngas BEFORE combustion (easier than from flue gas after combustion). Much lower emissions than direct coal burning.
India statusNational Coal Gasification Mission: Target 100 million tonnes of coal gasification by 2030. Methanol economy push. India exploring as alternative to direct coal combustion.
By-productSyngas can be used for fertiliser (ammonia/urea) production, chemicals (methanol), hydrogen extraction — multiple uses.
Pollution Index for Industries — CPCB’s Comprehensive Environmental Pollution Index (CEPI)
Comprehensive Environmental Pollution Index (CEPI)
- Developed by: Central Pollution Control Board (CPCB)
- Purpose: Measures the level of environmental pollution around industrial clusters. Score: 0–100. Score ≥70 = “critically polluted” area; 60–70 = “severely polluted”
- Parameters: Air quality (PM, SO₂, NOₓ), water quality (heavy metals, BOD), land quality, and health impacts on local population
- Moratorium: Industrial clusters scoring ≥70 get a development moratorium — no new industries allowed until pollution is controlled
- India’s most critically polluted clusters: Vapi (Gujarat), Singrauli (UP/MP border), Ankleshwar (Gujarat), Ludhiana (Punjab)
- UPSC angle: CEPI is a tool where India links industrial regulation to measurable environmental outcomes — related to Polluter Pays Principle
🔴 FGD Compliance Crisis — India’s Thermal Power Plants Current Affairs 2024-25
- Background: In 2015, MoEFCC ordered all coal-fired thermal power plants to install FGD (Flue Gas Desulphurisation) systems by 2017 to reduce SO₂ emissions
- Reality (as of 2025): Only 7% of thermal power plant units have installed FGD systems — nearly all of those are NTPC (National Thermal Power Corporation) plants
- December 2024 extension: MoEFCC extended FGD deadlines again:
- Category A (near cities/sensitive areas): December 31, 2027 (previously 2024)
- Category B: December 31, 2028
- Category C (remote plants): December 31, 2029
- Contracts awarded: 44% of units have contracts awarded or under implementation (1,05,200 MW) — but actual installation is far behind
- Controversy: CSIR-NEERI (2024) recommended against FGD installation, arguing SO₂ from India’s low-sulphur coal (92% of Indian coal has 0.3–0.5% sulphur) doesn’t significantly affect ambient air quality. Suggested prioritising PM control instead.
- CSE critique: Repeated deadline extensions indicate “weak enforcement and regulatory laxity”. Coal-based TPPs account for 47% of India’s installed power capacity (217 GW) and are the single largest SO₂ source.
- FGD by-product value: Gypsum produced by FGD is commercially valuable — can offset some installation costs. Used in cement and construction.
| Technology | Removes | Efficiency | Key Limitation | UPSC Key Fact |
|---|---|---|---|---|
| Baghouse Filter | PM (particulates) | >99% for PM | Only PM; no gases | Cotton/glass cloth fabric; best for dry particles |
| ESP (Electrostatic Precipitator) | Fine PM (dust, fly ash) | >99% PM removal | No gases; ineffective if ash has high resistivity | Standard in all coal plants; corona discharge ionises particles; collected on plates |
| Inertial Collector (Cyclone) | Coarse PM (>10 µm) | 70–90% coarse PM | Poor for fine PM; no gases | No moving parts; first-stage pre-cleaner; centrifugal force |
| Wet Scrubber | PM + soluble gases | Good for gases | Liquid waste; high operating cost | Water contact removes both PM and SO₂, HCl; like mucus in trachea |
| FGD (Flue Gas Desulphurisation) | SO₂ specifically | 90–99% SO₂ removal | ₹1.2 cr/MW cost; only 7% installed in India (2025) | Produces gypsum; SO₂ + CaCO₃ → gypsum (CaSO₄). Dec 2024 deadlines extended. |
| Catalytic Converter | CO, NOₓ, unburnt HC | 90%+ conversion | Only unleaded petrol; expensive metals | Pt/Pd/Rh catalysts; CO→CO₂; NOₓ→N₂; Mandatory BS-VI |
| Coal Gasification | Pre-combustion cleaning | Much lower emissions than direct coal burning | High capital cost; still under development | Coal → Syngas (CO+H₂); National Coal Gasification Mission: 100 MT by 2030 |
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PART B: Control of Vehicular Pollution
BS-VI · FAME I/II · PM E-DRIVE 2024 · Green Tax · EV 2030 targets · GRAP
💡 India’s Vehicular Pollution Response = A 3-Pronged Attack
India’s approach to vehicular pollution works on three levels simultaneously: (1) Make existing vehicles cleaner — BS-VI emission norms cut NOₓ by 70% and PM by 80% in diesel vehicles vs BS-IV. (2) Accelerate shift to zero-emission vehicles — FAME scheme, PM E-DRIVE, EV targets. (3) Emergency restrictions on worst polluters — Green Tax on old vehicles, GRAP restrictions under AQI triggers. These three work simultaneously — improve today’s vehicles while subsidising tomorrow’s EVs while restricting yesterday’s polluters.
BS-VI Emission Standards — India’s Biggest Single Step on Vehicular Pollution
BS-VI — Everything UPSC Needs
- Implemented: April 1, 2020 — India leapfrogged directly from BS-IV to BS-VI, skipping BS-V entirely
- Why leapfrog: India’s UNFCCC commitments (NDC targets) required faster action. Also economically efficient — one major industrial retooling instead of two. Equivalent to Euro-VI standards globally.
- Key difference BS-IV vs BS-VI: Sulphur content in fuel — BS-IV: 50 parts per million (ppm) | BS-VI: 10 ppm (ultra-low sulphur). This 80% sulphur reduction is what enables advanced emission control technologies to work effectively.
- Emission reductions vs BS-IV:
- PM (diesel vehicles): ↓ 80%
- NOₓ (diesel vehicles): ↓ 70%
- NOₓ (petrol vehicles): ↓ 25%
- CO, unburnt HC: significant reduction
- New technologies enabled by BS-VI fuel: DPF (Diesel Particulate Filter), SCR (Selective Catalytic Reduction using urea/AdBlue for NOₓ), OBD (Onboard Diagnostics — mandatory — monitors emissions in real-time)
- OBD mandate: All BS-VI vehicles must have Onboard Diagnostics that alert drivers if emission controls malfunction — a major enforcement improvement
Electric Vehicle Schemes — From FAME to PM E-DRIVE
2015
FAME I — Faster Adoption and Manufacturing of (Hybrid &) EVs
Budget: ₹895 crore. Duration: 2015–2019. Results: Supported 2.8 lakh EVs, 425 e-buses, 520 charging stations. Subsidies for 2W, 3W, buses, and hybrid vehicles.
2019
FAME II — Expanded Scope, Charging Infrastructure
Budget: ₹10,000 crore. Duration: 2019–March 2024. Focus: Subsidies for e-2W/3W/4W, e-buses; charging infrastructure (2,877 public charging stations approved). Results (June 2025): 16.29 lakh EVs supported — 14.35 lakh e-2W, 1.65 lakh e-3W, 22,644 e-4W, 5,165 e-buses.
Apr 2024
EMPS 2024 — Electric Mobility Promotion Scheme (Bridging Scheme)
Budget: ₹778 crore. Duration: April–September 2024. Replaced FAME-II temporarily. Subsidies for e-2W and e-3W only (not e-4W or e-buses). Later merged into PM E-DRIVE.
Oct 2024
PM E-DRIVE — Electric Drive Revolution in Innovative Vehicle Enhancement Latest
Budget: ₹10,900 crore. Duration: October 2024 – March 2026. Scope: e-2W, e-3W, e-ambulances, e-trucks, e-buses + 72,000 public charging stations (₹2,000 crore allocation). Incentive: ₹5,000/kWh for e-2W/3W in FY25; ₹2,500/kWh in FY26. Includes e-voucher system via Aadhaar face authentication. 5,71,411 e-2W sales in 2024-25 under EMPS+PM E-DRIVE.
2024
New EV Policy 2024 — India as Manufacturing Destination
Allows global EV makers to import fully built EVs at 15% customs duty (reduced from 100%) if they invest minimum ₹4,150 crore in local manufacturing within 3 years. Aimed at attracting Tesla, BYD, and other global players. Minimum vehicle CIF value: USD 35,000.
🚌 PM e-Bus Sewa — 10,000+ E-Buses
Target: 14,000 e-buses by 2026 for cities. BHEL = nodal agency for charging infrastructure under PM E-DRIVE. States like Karnataka, Telangana scaling up e-bus fleets rapidly.
🔋 PLI Scheme — Battery Manufacturing
Production Linked Incentive for Advanced Chemistry Cell (ACC) batteries and EV components. Mandatory 50% domestic value addition. ₹3,500 crore allocation in FY25. Reduces import dependence on China for EV batteries.
🚗 EV 2030 Targets (NEMMP)
National Electric Mobility Mission Plan: 30% private cars | 70% commercial vehicles | 40% buses | 80% two-wheelers and three-wheelers by 2030. ~80 million EVs on Indian roads by 2030.
💰 Green Tax on Old Vehicles
Vehicles older than 8 years must pay Green Tax when getting fitness certificate renewed. Higher tax for vehicles older than 15 years (to incentivise scrapping). Encourages fleet renewal with cleaner vehicles.
🚨 GRAP Restrictions on Vehicles
Under GRAP Stage 3 (AQI 401+): Ban on BS-III petrol and BS-IV diesel vehicles in Delhi-NCR. Stage 4 (AQI 450+): Possible odd-even rationing. Implemented by CAQM.
🔌 Charging Infrastructure
PM E-DRIVE: 72,000 charging stations (₹2,000 crore). Karnataka leads with ~6,097 public charging stations (July 2025). 8,885 stations installed under FAME-II. Bharat Charge Points on highway network.
🔴 EV Sector — Key 2024–25 Data Current Affairs
- FY 2023-24: Over 1.5 million EVs sold in India. Electric 2-wheelers dominate — 60% of EV market
- PM E-DRIVE results: 5,71,411 e-2W sales in 2024-25 under EMPS + PM E-DRIVE
- EV passenger car market: Surged 75% YoY in Q1 FY26; market penetration at 3.5% (up from 2%). Kerala leads with 7.9% penetration.
- Electric car sales August 2025: 17,298 units — 155% year-on-year rise from 6,787 in August 2024
- E-2W lead the market: Most affordable; urban mobility; supported by higher subsidy (₹5,000/kWh under PM E-DRIVE)
- Global comparison: China saw >50% of new cars as electric in 2024; India at ~3.5% penetration — significant gap remains
- India’s Zero-Emission Trucking: Top 10 priority corridors for e-truck deployment identified (May 2025 report). Heavy EV transition ongoing.
- Challenges: Range anxiety, insufficient charging (despite rapid build-up), high upfront cost, battery import dependence, shifting policies create uncertainty
⭐ Complete Pollution Control Cheat Sheet
- Baghouse Filter: Fabric filter | 99%+ PM removal | Cotton (low temp) / Glass cloth (up to 290°C) | Only particulates
- ESP: Electrostatic Precipitator | Ionises particles (corona discharge) | Collects on oppositely charged plates | >99% PM removal | Standard in all coal plants | Cannot remove SO₂
- Inertial Collector (Cyclone): Centrifugal force | Coarse PM only | No moving parts | First-stage pre-cleaner
- Wet Scrubber: Water contact | Removes PM + soluble gases | Like mucus in trachea
- FGD: Flue Gas Desulphurisation | Limestone slurry → absorbs SO₂ → produces gypsum | Cost: ₹1.2 crore/MW | India: only 7% installed (2025) | Dec 2024 extended deadlines: Cat A → 2027, B → 2028, C → 2029
- Catalytic Converter: Pt/Pd/Rh metals | CO→CO₂, NOₓ→N₂, HC→CO₂+H₂O | Unleaded petrol only (lead kills catalyst) | Mandatory BS-VI
- Coal Gasification: Coal → Syngas (CO+H₂) → cleaner combustion | National Coal Gasification Mission: 100 MT by 2030
- CEPI: Comprehensive Environmental Pollution Index | CPCB | Score ≥70 = critically polluted → development moratorium
- BS-VI: Implemented April 1, 2020 | Leapfrogged BS-V | Sulphur: BS-IV 50 ppm → BS-VI 10 ppm | PM ↓80%, NOₓ ↓70% (diesel) | OBD mandatory | Enables DPF + SCR
- FAME I: 2015-19 | ₹895 crore | 2.8L EVs, 425 e-buses, 520 charging stations
- FAME II: 2019-March 2024 | ₹10,000 crore | 16.29 lakh EVs supported (FAME II total)
- EMPS 2024: April-September 2024 | ₹778 crore | Bridge between FAME II and PM E-DRIVE | e-2W and e-3W only
- PM E-DRIVE: October 2024 – March 2026 | ₹10,900 crore | e-2W/3W/ambulances/trucks/buses + 72,000 charging stations | ₹5,000/kWh subsidy (FY25)
- New EV Policy 2024: Global makers → import at 15% duty (vs 100%) → must invest ₹4,150 crore locally within 3 years
- PLI-Auto: Advanced Chemistry Cell batteries | 50% domestic value addition mandatory | ₹3,500 crore FY25
- Green Tax: Vehicles >8 years → pay green tax on fitness certificate renewal. Incentivises fleet renewal.
- EV 2030 targets: Cars 30% | Commercial vehicles 70% | Buses 40% | 2W+3W 80% | ~80 million EVs
- India EV status 2024-25: 1.5M EVs sold FY24 | e-2W = 60% of market | 3.5% passenger car penetration | Kerala leads (7.9%)
🧪 Practice MCQs — Test Yourself
Q1. With reference to ‘Bharat Stage VI’ vehicle emission norms, consider the following statements:
1. The norms indicate the maximum permissible emission levels.
2. India leapfrogged from BS IV to BS VI skipping BS V.
3. BS VI norms for two-wheelers have been waived for five years.
Which is/are CORRECT?
✅ Official Answer: 1 and 2 only (Statement 3 is FALSE)
Statement 1 ✅: Bharat Stage emission norms indicate the maximum permissible emission levels for vehicles — they set the upper limit for CO, NOₓ, PM, and unburnt hydrocarbons that vehicles can emit. Statement 2 ✅: India directly leapfrogged from BS-IV to BS-VI in April 2020, skipping BS-V entirely. This was done to meet India’s NDC commitments and because the technology investment for one leap was more economical. Statement 3 ❌ WRONG: BS-VI norms were NOT waived for two-wheelers. BS-VI applied to ALL vehicle categories including two-wheelers from April 1, 2020. This was a deliberate choice because two-wheelers are the largest vehicle category in India and a major source of urban pollution. The key difference BS-IV vs BS-VI: sulphur in fuel drops from 50 ppm to 10 ppm; PM in diesel vehicles ↓80%; NOₓ in diesel ↓70%.
Q2. An Electrostatic Precipitator (ESP) used in thermal power plants works by which principle?
✅ Answer: (c) — Corona discharge ionises particles → attracted to collecting plates
An Electrostatic Precipitator works through electrostatics: (1) High-voltage electrode wires (maintained at thousands of volts) create a corona discharge — a zone of ionised air around the wire. (2) Electrons from the corona discharge attach to dust/fly ash particles, giving them a net negative charge. (3) The collecting plates are grounded (relatively positive) — the negatively charged particles are attracted to these plates. (4) The particles stick to the plates and are periodically dislodged by mechanical rapping → fall into hoppers for collection. Key advantage: Can remove >99% of PM including fine particles, with minimal flow restriction. Key limitation: Does NOT remove gaseous pollutants like SO₂ — that requires FGD (scrubbers). Option (a) describes a Baghouse Filter. Option (b) describes an Inertial Collector/Cyclone. Option (d) describes a Wet Scrubber.
Q3. Consider the following about FGD (Flue Gas Desulphurisation) in India’s thermal power plants (as of early 2025):
1. India mandated FGD installation in all coal-fired power plants in 2015.
2. As of 2025, approximately 7% of thermal power plant units have actually installed FGD systems.
3. FGD produces gypsum as a by-product, which can be used in cement and construction.
4. India’s coal has high sulphur content (above 2%), making FGD essential.
Which are CORRECT?
✅ Answer: (c) — 1, 2 and 3 only. Statement 4 is WRONG.
1 ✅: In December 2015, MoEFCC mandated FGD installation in all coal-fired thermal power plants — originally with a 2017 deadline. 2 ✅: Despite the 2015 mandate, as of 2025 only about 7% of thermal power unit capacity has actually installed FGD — mostly NTPC plants. The December 2024 notification extended deadlines again to 2027-2029 by category. 3 ✅: FGD’s chemical reaction (SO₂ + CaCO₃ limestone → CaSO₄·2H₂O gypsum) produces gypsum as a by-product. This gypsum is commercially valuable — used in construction, cement manufacturing, wallboard (drywall) production. This is an example of circular economy principles. 4 ❌ Wrong: India’s coal has LOW sulphur content — 92% of Indian coal has only 0.3–0.5% sulphur (NOT above 2%). This is actually one reason CSIR-NEERI (2024) argued FGD may not be the most urgent priority — suggesting India should focus on particulate matter control instead. High-sulphur coal is found mainly in imported coal used in coastal power plants.
Q4. The PM E-DRIVE scheme (PM Electric Drive Revolution in Innovative Vehicle Enhancement), launched in October 2024, has a total financial outlay of approximately:
✅ Answer: (c) ₹10,900 crore
The PM E-DRIVE (PM Electric Drive Revolution in Innovative Vehicle Enhancement) Scheme was approved by the Cabinet with an outlay of ₹10,900 crore, effective from October 1, 2024 to March 31, 2026. It covers: Demand incentives for e-2W, e-3W, e-ambulances, e-trucks; Capital grants for e-buses; 72,000 public EV charging stations (₹2,000 crore specifically for charging); Upgradation of testing facilities. The other options for context: ₹778 crore = EMPS 2024 (April-September 2024, bridging scheme); ₹10,000 crore = FAME-II (2019-2024). The PM E-DRIVE scheme subsumes EMPS 2024 and is the successor to FAME-II, with a slightly larger budget and a new focus on e-trucks, e-ambulances, and extensive charging infrastructure.
Q5. A catalytic converter fitted in a vehicle converts pollutants using platinum, palladium, and rhodium as catalysts. Which of the following is NOT a correct statement about catalytic converters?
✅ Answer: (c) — This is WRONG. Leaded petrol DESTROYS the catalyst permanently.
This is one of UPSC’s most classic pollution control questions. Catalytic converters CANNOT work with leaded petrol — this is a critical fact. (c) is WRONG because: Lead (Pb) in leaded petrol acts as a catalyst poison — it coats the surface of the platinum, palladium, and rhodium catalysts, permanently deactivating them. Even small amounts of leaded fuel can permanently destroy the expensive catalyst. This is why India banned leaded petrol in 2000 — a necessary prerequisite for catalytic converters to work nationwide. (a) ✅ Correct: CO + O → CO₂ (oxidation catalyst). (b) ✅ Correct: NOₓ → N₂ + O₂ (reduction catalyst). (d) ✅ Correct: Unburnt hydrocarbons → CO₂ + H₂O (oxidation). Modern 3-way catalytic converters do all three reactions simultaneously. BS-VI vehicles also add SCR (Selective Catalytic Reduction) using urea (AdBlue) specifically for more aggressive NOₓ reduction.
📜 UPSC Previous Year Questions (PYQs)
How is the National Green Tribunal (NGT) different from the Central Pollution Control Board (CPCB)?
1. The NGT has been established by an Act whereas the CPCB has been created by an executive order of the Government.
2. The NGT provides environmental justice and helps reduce the burden of litigation in the higher courts whereas the CPCB promotes cleanliness of streams and wells, and aims to improve the quality of air in the country.
Which of the statements given above is/are correct?
✅ Official Answer: (b) 2 only
Statement 1 ❌ Wrong: The CPCB (Central Pollution Control Board) was established under the Water (Prevention and Control of Pollution) Act, 1974 — it is also a statutory body established by legislation, NOT by executive order. The NGT was established by the National Green Tribunal Act, 2010. Both are statutory bodies established by Acts of Parliament. The statement is factually incorrect in claiming CPCB was created by an executive order. Statement 2 ✅ Correct: The NGT provides environmental justice (quasi-judicial body) and reduces burden on higher courts for environmental disputes. The CPCB promotes cleanliness of streams and wells (water quality mandate under the Water Act, 1974) and improves air quality (Air Act, 1981). The functional descriptions of both bodies are accurately stated here. Key distinction: NGT = judicial/quasi-judicial body for environmental disputes. CPCB = regulatory/technical body for monitoring and standard-setting.
With reference to ‘Bharat Stage VI’ vehicle emission norms, consider the following statements:
1. The norms indicate the maximum permissible emission levels.
2. India leapfrogged from Bharat Stage IV to Bharat Stage VI skipping Bharat Stage V.
3. Bharat Stage VI norms for two-wheelers were waived for five years.
Which of the statements given above is/are correct?
✅ Official Answer: (a) 1 and 2 only
Statement 1 ✅: Bharat Stage emission norms indicate the maximum permissible emission levels — they set the upper limit for CO, NOₓ, PM, and HC that vehicles can emit. Statement 2 ✅: India directly leapfrogged from BS-IV (applicable nationwide from April 2017) to BS-VI in April 2020, skipping BS-V entirely. Reason: UNFCCC commitments, India’s NDC targets, and the Supreme Court’s October 2018 order. Economically efficient — one major industrial retooling instead of two. BS-VI is equivalent to Euro-VI standards globally. Key improvement: Sulphur in fuel drops from 50 ppm (BS-IV) to 10 ppm (BS-VI). Statement 3 ❌ Wrong: BS-VI norms were NOT waived for two-wheelers. BS-VI applied to all vehicle categories simultaneously from April 1, 2020 — including two-wheelers, three-wheelers, cars, buses, and trucks. There was no exemption. Two-wheelers are actually a critical target because India has the world’s largest two-wheeler fleet and they are a major urban PM and HC source.
According to the Environmental Protection Agency (EPA), which one of the following is the largest source of sulphur dioxide emissions?
✅ Official Answer: (c) Fossil fuel combustion — power plants and industries
According to the US EPA (and consistent with global environmental data), fossil fuel combustion in power plants and industries is the single largest source of SO₂ emissions. This is because coal and petroleum contain sulphur compounds — when burned, sulphur oxidises to SO₂. Coal-fired thermal power plants are the dominant source. In India specifically: thermal power plants account for the overwhelming majority of SO₂ emissions — which is precisely why FGD installation in thermal power plants is so important. Vehicles (a): Much lower SO₂ from petrol/diesel since BS-VI reduced sulphur in fuel to just 10 ppm. Not a major SO₂ source. Agricultural burning (b): Mainly produces PM, CO, and black carbon — minimal SO₂. Volcanic eruptions (d): Do emit SO₂ but are sporadic/natural events — NOT the primary human-caused source. The FGD crisis in India (only 7% compliance as of 2025) is directly relevant to this question — India’s power plants are its largest SO₂ source, and the long-delayed FGD mandate is supposed to address this.
Consider the following statements regarding mercury pollution:
1. Gold mining activity is a source of mercury pollution in the world.
2. Coal-based thermal power plants cause mercury pollution.
3. There is no known safe level of exposure to mercury.
How many of the above statements are correct?
✅ Official Answer: (c) All three are correct
Statement 1 ✅: Gold mining uses mercury (Hg) in artisanal and small-scale gold mining (ASGM) to separate gold from ore — mercury amalgamates with gold, then is heated to evaporate the mercury. This releases mercury vapour into the atmosphere and liquid mercury into water bodies. ASGM is the world’s largest source of anthropogenic mercury pollution. Statement 2 ✅: Coal naturally contains mercury. When coal is burned in thermal power plants, mercury is released as flue gas. ESP and FGD can capture some mercury, but without specific mercury control equipment, significant mercury escapes. Coal-fired power plants are the second-largest source of mercury pollution globally (after ASGM). This directly connects to the industrial pollution control topic — yet another reason why better scrubbing technologies and FGD matter. Statement 3 ✅: According to WHO and EPA, there is no known safe level of mercury exposure — any exposure carries health risks. Mercury is a potent neurotoxin causing brain damage (especially in developing fetuses), kidney damage, immune suppression. The Minamata Convention (2013) specifically targets mercury pollution globally.
Consider the following statements:
1. Coal ash contains uranium and thorium which are radioactive elements.
2. Coal ash is generated as a pollution-free by-product of coal-based power generation.
3. A part of coal ash can be used in the production of building materials.
Which of the statements given above is/are correct?
✅ Official Answer: (c) 1 and 3 only
Statement 1 ✅: Coal ash (fly ash) contains trace amounts of uranium (U) and thorium (Th) — naturally occurring radioactive elements present in the coal that get concentrated in the ash after combustion. While the levels are low, they are slightly above background levels. Large-scale fly ash disposal (ash ponds) can cause radioactive leaching into groundwater — a lesser-known pollution concern. Statement 2 ❌ Wrong: Coal ash is NOT pollution-free. It contains heavy metals (arsenic, mercury, cadmium, lead, chromium), radioactive elements (U, Th), and toxic organic compounds. Unmanaged ash ponds can contaminate soil and groundwater. Fly ash that escapes ESPs contributes to PM pollution. The correct statement should say “coal ash is a by-product” — but NOT a “pollution-free” one. Statement 3 ✅: Fly ash (coal ash) IS used in construction materials — in cement manufacturing (as a pozzolanic additive replacing some Portland cement), bricks, concrete blocks, and road sub-base. India mandates use of fly ash in construction within 100 km of thermal plants. This is both a waste management solution and reduces the need for other raw materials. Connecting to our topic: fly ash collected by ESPs and FGD systems is commercially valuable for construction.
Mains GS Paper 3: “Describe the key issues related to India’s attempts to control vehicular pollution in its cities.” [For Prelims practice based on this topic]
Which of the following correctly describes the Perform, Achieve and Trade (PAT) Scheme?
✅ Answer: (c) PAT = market-based energy efficiency scheme for industries
The PAT (Perform, Achieve and Trade) Scheme is one of India’s most important industrial pollution control mechanisms — and directly relevant to this chapter. Key facts: (1) What it is: A regulatory and market-based mechanism to enhance energy efficiency of energy-intensive large industries. (2) Under: Bureau of Energy Efficiency (BEE), Ministry of Power, under the National Mission for Enhanced Energy Efficiency (NMEEE) — part of NAPCC. (3) How it works: Energy-intensive industries (thermal power plants, steel, cement, aluminium, fertiliser, textile, paper, chemicals) are given energy consumption targets. Industries that exceed (over-perform) their targets earn Energy Saving Certificates (ESCerts). Industries that under-perform must buy ESCerts from over-performers — creating a market incentive for efficiency. (4) Why it reduces industrial air pollution: More energy-efficient industries burn less fuel → less SO₂, NOₓ, PM, and CO₂ emissions. (5) India’s progress: PAT cycles have covered 13 energy-intensive sectors. Combined with the FGD mandate and ESP upgrades, PAT is a key part of India’s industrial pollution reduction framework. The Mains question connects: effective vehicular pollution control requires BS-VI, EVs, public transport expansion, parking policies, odd-even schemes, and fuel switching — but also addressing industrial pollution that compounds urban air quality problems.
❓ Frequently Asked Questions
This is a genuinely complex policy question with competing considerations: Arguments for extending deadlines: (1) 92% of Indian coal has very low sulphur content (0.3–0.5%), so SO₂ emissions are inherently lower than from high-sulphur coal elsewhere. (2) CSIR-NEERI’s 2024 study suggested India’s 220-metre stack heights and climatic conditions already dilute SO₂ adequately at ground level. (3) FGD installation costs ~₹1.2 crore per MW — for 217 GW of coal capacity, total cost would be ~₹26,000 crore — a massive burden on already-stressed power distribution companies. (4) India’s energy security depends on coal — disrupting 71% of electricity generation for FGD retrofits has real economic consequences. Arguments against extending: (1) SO₂ converts to secondary PM2.5 (sulphate aerosols) in the atmosphere — so even if ground-level SO₂ stays within limits, it contributes to the PM2.5 crisis. (2) Repeated extensions signal regulatory weakness — undermining environmental governance credibility. (3) NTPC has installed FGD successfully, proving it’s technically feasible for other plants too. (4) Acid rain and regional ecosystem damage still occur, even if ground-level SO₂ is diluted. The bottom line: It’s a classic “environment vs development” tension — India’s energy security (cheap coal) vs long-term health and environmental costs.
India’s EV position globally (2024-25): India sold 1.5 million EVs in FY24 — significant in absolute terms but only ~3.5% of total vehicle sales. China sees >50% of new cars as electric; Europe ~25%; USA ~11%. India is far behind. However, India is growing fast — passenger EV sales surged 75% YoY in Q1 FY26. Electric 2-wheelers (60% of India’s EV market) are already approaching meaningful penetration due to affordability. Why India lags: (1) Upfront cost: EVs cost significantly more than comparable petrol vehicles; Indian buyers are very price-sensitive. (2) Charging infrastructure: India has 8,885 public charging stations vs petrol pumps counting in hundreds of thousands. (3) Range anxiety: India’s road network and charging density make long-distance EV travel stressful. (4) Electricity grid: Much of India’s electricity comes from coal — charging EVs on coal power doesn’t fully eliminate emissions. (5) Battery sourcing: India is heavily dependent on China for lithium-ion batteries — a strategic vulnerability. (6) Policy stability: Rapid policy changes (FAME I → FAME II → EMPS → PM E-DRIVE) create uncertainty for manufacturers. What’s working: The e-2W segment (scooters, motorcycles) has a compelling economics case — lower purchase price, lower running costs, easy home charging. This is India’s EV success story, and it’s growing rapidly. Government’s 80% e-2W target by 2030 may actually be achievable.
Legacy IAS — UPSC Civil Services Coaching, Bangalore |
FGD compliance data: Down To Earth (January 2025) — “only 7% installed, Dec 2024 deadline extension to 2027-29.” PM E-DRIVE scheme details from PIB (October 2024) and Ministry of Heavy Industries. EV market data from IBEF (July 2025) — 16.29 lakh EVs under FAME-II; 75% YoY passenger EV growth Q1 FY26; 17,298 e-car sales August 2025 (155% YoY). CSIR-NEERI FGD controversy from IAS Gyan analysis (August 2024 meeting). BS-VI emission reductions from PMF IAS official data. CEPI from CPCB guidelines.
