impact assessment (EIA) is a tool that seeks to ensure sustainable
development through the evaluation of those impacts arising from a major
activity (policy, plan, program, or project) that are likely to have
significant environmental effects. It is anticipatory, participatory, and
systematic in nature and relies on multidisciplinary input (Glasson et al.
The phrase Environmental Impact Assessment comes from Sec. 102 (2)
of the National Environmental Policy Act (NEPA), 1969, USA. Some rudiments
of EIA are implicit even in early examples of environmental legislation.
Napoleon in 1910 issued a decree which divided noxious occupations into
categories: those which must be far removed from habitations, those which
may be permitted on the outskirts of towns, and those which can be
tolerated even close to habitations, having regard to the importance of
the work and the importance of the surrounding dwellings. Now the EIA has
become a requirement in more than 100 countries (Canter 1996). In many
European countries, it came into vogue with the introduction of the
concept of sustainable development after the World Commission of
Environment in 1987. In India, though EIA came into existence around
1978-79 , it was made mandatory only in 1994.
Following sections will give more detailed information on EIA :