Environmental Impact Assessment (EIA) in India: UPSC Notes

By Dooit UPSC expert · 31 October 2026 · 11 min read

Environmental Impact Assessment (EIA) is the process of studying, before a project is approved, the damage it is likely to do to the environment — and deciding on that basis whether to clear it, clear it with conditions, or reject it. In India this runs under the EIA Notification 2006, issued under the Environment (Protection) Act, 1986, and a project cannot lawfully begin without prior Environmental Clearance.

In three decades of mentoring aspirants, I have seen Environment grow from a side-topic into one of the most reliably examined areas of the UPSC syllabus — and within it, EIA is the piece candidates get half-right most often. They remember the phrase "Environmental Impact Assessment", they know there was a controversy around 2020, and then the answer runs dry. That is a waste, because EIA is one of those rare topics where the facts are finite, the process is logical, and a well-organised note earns marks in Prelims and Mains alike. This guide gives you the complete, exam-safe foundation: what EIA is, the law behind it, the categories, the four stages, the single-window portal, and the debate the examiner expects you to understand without taking sides.

Why environmental impact assessment matters for UPSC

Before you learn the content, see where it pays. A strategic aspirant always does this.

• Prelims (GS Paper 1): Clean factual questions — the parent Act, the year of the current Notification, who clears Category A versus Category B, what the PARIVESH portal is. These are learnable, low-ambiguity marks.
• Mains GS Paper 3: EIA sits explicitly under "conservation, environmental pollution and degradation". Expect analytical questions on balancing growth with ecological safeguards, or on reforming the clearance process.
• Mains GS Paper 2: Governance angle — public participation, transparency, and the role of regulatory bodies and tribunals.
• Essay & Ethics: The development-versus-environment dilemma and intergenerational equity are classic prompts where an EIA example lifts an abstract answer into the concrete.

Notice the leverage. A topic that pays in four papers deserves a tight, well-revised note — not a vague memory of a news headline.

What is EIA, and the law behind it

Strip away the jargon and EIA is common sense formalised: look before you leap. A proponent who wants to build a thermal power plant, mine coal, construct a large dam or set up a chemical factory must first commission a study of what that project will do to air, water, soil, forests, wildlife and the people living nearby. The regulator reads that study, hears the affected public, and then decides. If the project is cleared, it comes with binding environmental conditions the proponent must follow.

The legal spine is the Environment (Protection) Act, 1986 — the umbrella law passed in the aftermath of the 1984 Bhopal gas tragedy, which empowers the Central Government to take all measures necessary to protect and improve environmental quality. EIA is not a separate statute; it is a notification issued using powers under this Act. That distinction matters for Prelims: EIA can be amended by executive notification without a fresh law in Parliament, which is exactly why the 2020 draft could be floated the way it was.

The legal journey — a timeline to memorise

Examiners love a clean sequence of dates. Learn this spine and most Prelims questions fall into place.

One fact aspirants routinely miss: the 2006 Notification was a genuine shift, not a tweak. It handed a large share of projects to state authorities, which is why "decentralisation" is the keyword examiners associate with 2006.

Category A versus Category B — who clears what

Every project covered by the Notification falls into one of two buckets, decided by its size, capacity and pollution potential.

Hold on to the logic, not just the table. Category A is centralised precisely because the projects are the ones with the widest footprint. Category B was devolved to the states to cut delays — and the B1/B2 sub-split exists so that genuinely small projects are not dragged through a full study they do not need. If a SEIAA has not been constituted in a state, the Centre steps in and clears Category B projects there too.

The four stages of the EIA process

This is the heart of the topic and the part most worth drawing as a flow. The 2006 Notification lays out four stages in sequence.

• Stage 1 — Screening: Applies only to Category B projects. The authority decides whether the project needs a detailed EIA study (making it B1) or not (B2). Category A projects skip this stage entirely because a full EIA is mandatory for them.
• Stage 2 — Scoping: The Expert Appraisal Committee draws up the Terms of Reference (ToR) — the specific environmental concerns the EIA report must address, tailored to that project and its location. Good scoping is what stops an EIA from becoming a vague, copy-paste document.
• Stage 3 — Public Consultation: This has two parts — a public hearing at the project site for locally affected persons, and an invitation for written responses from other interested parties. This is the democratic heart of the process. Certain categories (and most B2 projects) are exempt, which is exactly where the fiercest debates about EIA happen.
• Stage 4 — Appraisal: The EAC (for Category A) or SEAC (for Category B) studies the final EIA report together with the outcome of public consultation, and makes a recommendation to the regulatory authority to grant Environmental Clearance — with conditions — or to reject it.

One subtlety worth a mark: public consultation feeds into appraisal, but the committees are advisory. The final grant or refusal of clearance rests with the regulatory authority — the MoEFCC for Category A and the SEIAA for Category B.

PARIVESH — the single-window portal

Since 2018 the entire clearance machinery has moved online through PARIVESH (Pro-Active and Responsive facilitation by Interactive and Virtuous Environmental Single-window Hub), launched by the MoEFCC. It is a single web platform where proponents submit and track applications for environmental, forest, wildlife and Coastal Regulation Zone (CRZ) clearances. For UPSC, remember PARIVESH as the governance-reform answer: it was designed to cut delays, reduce discretion and improve transparency by putting the whole trail — application, ToR, committee minutes, conditions — in one place. It is a textbook "e-governance meets environment" example for GS2 and GS3.

The Draft EIA Notification 2020 — understand the debate, don't take sides

In 2020 the Ministry released a draft EIA Notification meant to replace the 2006 regime. It triggered an unusually large public response and remained a draft; the 2006 Notification continues in force. You should know the main points of contention because the examiner tests your ability to weigh them, not your opinion:

• Post-facto clearance: The draft proposed a route to regularise projects that had already begun operating without prior clearance. Critics argued this inverts the basic logic of EIA, which is to assess before construction.
• Narrower public consultation: Proposals to shorten the notice period for public hearings and to expand the list of exempt projects were seen as shrinking the space for affected communities to be heard.
• More exemptions: A longer list of projects placed outside the full process raised concerns about ecologically significant activities escaping scrutiny.

In an answer, present the tension honestly: proponents of reform point to crippling delays and investment uncertainty; critics point to weakened public participation and the precautionary principle. A trained candidate lays out both and lands on a balanced, reform-with-safeguards position.

Criticisms and limitations

A one-sided answer loses marks. Be ready to discuss where India's EIA regime falls short: EIA reports are often prepared by consultants paid by the project proponent, raising conflict-of-interest worries; public hearings can be poorly attended or held far from affected communities; monitoring of post-clearance conditions is frequently weak; and the sheer volume of exemptions means many projects escape detailed scrutiny. The counterweight to many of these gaps is the National Green Tribunal, which has repeatedly reviewed and set aside flawed clearances — a link worth making in any governance-flavoured answer.

How to revise this for the exam — a coach's method

Do not re-read the notification ten times. Instead, build a one-page note with four blocks: (1) the law chain — Bhopal 1984 → EP Act 1986 → EIA 1994 → EIA 2006; (2) the A/B table; (3) the four-stage flow you saw above, drawn by hand so your pen remembers it; and (4) the 2020 debate in three bullets. Then test yourself: close the page and reproduce the four stages from memory. If you can draw the flow and name who clears Category A versus B, you have the Prelims marks. For Mains, practise one 150-word answer on "balancing development and environment" using EIA as your central example. This topic rewards structured revision over volume, which is exactly the discipline our environment and ecology preparation strategy is built around — and the same spaced, test-driven loop that underlies everything at Dooit.

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