Environmental impact assessment

The first principle

Damage to the environment is far cheaper to prevent than to repair, and much of it, such as a drowned forest or a drained aquifer, cannot be repaired at all. Environmental impact assessment (EIA) therefore asks a simple question before a project begins: what will it change, can the change be reduced, and is the remaining harm worth the benefit? Its value rests on three conditions. The study must be honest, the people affected must be heard while the decision can still change, and approval must come before construction. Every debate about EIA in India is about one of these three conditions.

The core

Legal basis and categories

• A notification, not an Act. India has no separate EIA law. The Ministry of Environment, Forest and Climate Change (MoEFCC) issued the first EIA notification on 27 January 1994 under the Environment (Protection) Act, 1986, and replaced it with the EIA Notification of 14 September 2006, which remains in force with many amendments.
• Prior environmental clearance. The schedule of the notification lists the projects that need clearance, such as mining, thermal power, river valley projects, industrial units, ports and large construction, and requires that clearance be obtained before any construction or land preparation begins, other than securing the land.
• Category A and Category B. Projects above set size or capacity thresholds fall in Category A and are appraised at the Centre by an Expert Appraisal Committee (EAC), with the MoEFCC deciding. Smaller projects fall in Category B and are appraised in the State by a State Expert Appraisal Committee (SEAC), with the State Environment Impact Assessment Authority (SEIAA) deciding. A Category B project becomes Category A if it lies within 10 kilometres of a protected area, a critically polluted area, an eco sensitive area or an interstate or international boundary.
• B1 and B2. Category B projects are split at screening: B1 projects need a full EIA report, while B2 projects need none and skip the public hearing.

The four stages

• Screening applies only to Category B and decides whether a project is B1 or B2 on the application in Form 1.
• Scoping fixes the terms of reference, the questions the EIA report must answer, and the committee must issue them within 60 days of the application. The proponent then hires an accredited consultant, accredited through the Quality Council of India, to collect baseline data, usually for one season other than the monsoon, and prepare a draft report.
• Public consultation has two parts: a public hearing at or near the site, organised by the State Pollution Control Board, which must be completed within 45 days of the request after at least 30 days' public notice, and written responses from others with a stake in the project. Certain projects, including B2 projects and those inside notified industrial estates, are exempt from the hearing.
• Appraisal is the committee's detailed scrutiny of the final report and the hearing record, completed within 60 days, after which the regulatory authority must decide within 45 days. After clearance, the proponent files six monthly compliance reports, which the Ministry's regional offices are meant to check.

Dimensions

• Environmental. EIA is the only point at which air, water, forest and wildlife impacts of a project are considered together, and mitigation such as a green belt or an environmental flow is written into the clearance conditions.
• Social and democratic. The public hearing is often the only formal voice that affected communities have, and in the Niyamgiri case (Orissa Mining Corporation v Ministry of Environment and Forests, 2013) the Supreme Court gave the gram sabhas the decisive say on bauxite mining under the Forest Rights Act.
• Economic. Investors want certainty and speed, which is why governments have shortened timelines and widened exemptions, while weak assessment shifts the cost of damage onto the public later.
• Legal. The word "prior" is the core of the regime, and the question whether clearance can be granted after work has started has reached the Supreme Court repeatedly.
• Scientific. A study paid for by the proponent and based on a single season of data can miss migratory species, floods and groundwater effects, so the quality of the science decides the quality of the decision.
• Spatial. Each project is assessed alone, although a river with ten dams or a district with fifty mines suffers their combined effect.

In practice

• Common Cause v Union of India (2017). The Supreme Court held that mining in Odisha without a valid clearance, or beyond the cleared quantity, was illegal, and ordered compensation equal to the full price of the ore extracted illegally.
• Alembic Pharmaceuticals v Rohit Prajapati (2020). The Court held that ex post facto environmental clearance is alien to environmental jurisprudence and contrary to the 2006 notification, though it imposed compensation on the units rather than ordering their closure.
• The amnesty instruments. A notification of 14 March 2017 opened a six month window for projects already running without clearance to apply, and an office memorandum of 7 July 2021 laid down a standing procedure for such violation cases.
• Vanashakti v Union of India. On 16 May 2025 a two judge bench struck down both the 2017 notification and the 2021 office memorandum. On 18 November 2025 a three judge bench recalled that judgment by a majority of two to one and ordered a fresh hearing. On 29 July 2026 the Court held that prior clearance remains mandatory, upheld the 2017 notification as a narrow, one time amnesty, and quashed the 2021 office memorandum because it created a standing route to clearance after violation.
• The draft EIA Notification 2020. Published in March 2020 to replace the 2006 notification, it proposed cutting the public hearing notice from 30 to 20 days, allowing annual instead of six monthly compliance reports, extending the validity of mining clearances and creating a procedure for violation cases. It drew wide public objection and court challenges and has not been notified in final form; the 2006 notification has instead been amended piecemeal.
• Cumulative impact in the Himalaya. After the 2013 floods in Uttarakhand, the Supreme Court in Alaknanda Hydro Power v Anuj Joshi (2013) halted new clearances for hydropower projects in the State and asked for an expert study of whether the existing and proposed projects had worsened the disaster.

Issues and way forward

• The proponent pays the consultant. A consultant hired and paid by the project has every reason to write a favourable report, and copied or inaccurate reports have been found repeatedly; an independent body that commissions studies from a pooled fund, as many experts have proposed, would break the conflict of interest.
• Hearings that cannot change outcomes. Reports are often unavailable in local languages, hearings are held far from the affected villages, and objections are rarely answered in the clearance; publishing a reasoned response to every objection would give the hearing real weight.
• Monitoring is the weakest link. The Ministry's regional offices are too thinly staffed to check thousands of compliance reports, so conditions go unenforced; satellite monitoring, public compliance data on the PARIVESH portal (the online single window for clearances since 2018) and penalties tied to project value would help.
• Violations and amnesties. Repeated windows for regularisation tell proponents that building first pays; the July 2026 judgment now confines such relief to a narrow, one time window, and the remedy is to make violation costlier than compliance.
• No strategic or cumulative assessment. Strategic environmental assessment (SEA) examines a policy, plan or programme, such as a State's hydropower plan or a coastal development plan, before individual projects are chosen; cumulative impact assessment adds up the effects of many projects in one area. Neither is mandatory in India, although the European Union has required SEA since a directive of 2001.
• One regulator. The T.S.R. Subramanian committee (2014) recommended a National Environment Management Authority to appraise projects professionally, and the Supreme Court in the Lafarge case (2011) asked for a national regulator; neither exists.

Common confusions

• Screening and scoping. Screening decides whether a Category B project needs a full study at all, while scoping decides what the study must cover.
• Environmental clearance and forest clearance. Environmental clearance is granted under the EIA Notification for the project's overall impact, while forest clearance is granted under the forest law for diverting forest land, and a project on forest land needs both.
• Consent and clearance. Clearance is a one time permission from the Ministry or the SEIAA before construction, while consent to establish and consent to operate are permissions from the State Pollution Control Board under the Water and Air Acts.
• EIA and SEA. EIA assesses a single project after it has been chosen, while SEA assesses a policy or plan before projects are chosen.
• Ex post facto clearance and amnesty. The Court has rejected clearance after violation as a standing procedure, but it accepts a narrow, time bound statutory amnesty such as the 2017 window.

For the exam

• Keyword bank: prior environmental clearance, Category A and B, screening, scoping, terms of reference, public hearing, appraisal, Expert Appraisal Committee, accredited consultant, compliance monitoring, ex post facto clearance, time bound amnesty, strategic environmental assessment, cumulative impact assessment, precautionary principle.
• Previous year questions: Practise the previous year questions on this topic →
• Use in an answer:
  • Introduction with data: The EIA Notification of 2006 sets four stages before a project can begin, and the public hearing in it must be completed within 45 days, often the only time affected people are heard.
  • Introduction with a judgement: In Vanashakti v Union of India (July 2026), the Supreme Court reaffirmed that prior environmental clearance is mandatory and struck down a standing route to clearance after violation.
  • Conclusion: India's EIA regime is strongest on paper and weakest in practice, and an independent agency to commission studies and monitor compliance would do more than any new notification.
  • Conclusion: The next reform should move assessment upstream, from single projects to plans and river basins, so that cumulative and strategic impacts are weighed before the first project is cleared.