An Environmental Impact Assessment (EIA) is an assessment of the likely human environmental health impact, risk to ecological health, and changes to nature's services that a project may have. The purpose of the assessment is to ensure that decision-makers consider environmental impacts before deciding whether to proceed with new projects.
As the name implies, it is a technique for assessing the environment. It is done with regard to development projects. Environment' comes from the French word for surroundings. All projects affect their surroundings. If they produce an improvement (better views, less pollution, more wildlife) we are all pleased to note the beneficial side-effect' or positive externality' or positive environmental impact'. If, as happens more often, the affect on the environment is harmful, society has a right to protest - and a need to employ environmental designers.
There are two main types of legislation which are used to regulate the impact of projects on the environment:
1. Zoning Regulations (including Land Use Plans and Town Plans)
2. EIA Regulations
What is Environmental Impact Assessment?
The Environmental Impact assessment6 can be defined as:
Environmental impact assessment is, in its simplest form, a planning tool that is now generally regarded as an integral component of sound decision making... As a planning tool it has both information gathering and decision making component which provides the decision maker with an objective basis for granting or denying approval for a proposed development.
Justice La Forest, Friends of the Old man v. Canada et al. (1991) Environmental Impact Assessment (EIA) may be defined as a formal process used to predict the environmental consequences of any development project. EIA thus ensures that the potential problems are foreseen and addressed at an early stage in the projects planning and design.
A process or set of activities designed to contribute pertinent environmental information to project or Programme decision-making. ... A process which attempts to identify, predict and assess the likely consequences of proposed development activities. ... A planning aid concerned with identifying, predicting and assessing impacts arising from proposed activities such as policies, Programmes, plans and development projects which may affect the environment. ... A basic tool for the sound assessment of development proposals to determine the potential environmental, social and health effects of a proposed development
When it became apparent that the zoning system was not creating or protecting zones of environmental quality, it was supplemented by a second approach. Basically, the new idea was to assess each project as it arrived on the development agenda and discover what impact it would have on its surroundings. This became known as Environmental Assessment (EA) or Environmental Impact Assessment (EIA). [EA is the preferred term, partly because it leaves open the possibility that a development will have no impact whatsoever]. The concept of EA originated in America, partly because of its extra-rigid system of zoning. Planning control in some American states was much less comprehensive than in Europe and there was great public concern about the harmful affect which individual development projects were having on the environment. The National Environmental Policy Act (NEPA) of 1969 became a model for similar legislation throughout the world.
The key NEPA provision was that an Environmental Impact Statement (EIS) must be prepared for 'all major Federal actions significantly affecting the quality of the human environment'. The word 'actions' included building a house, planting a forest, felling a forest, laying a pipeline or carrying out a military exercise. The great value of the EA approach was that it included every influence of every project on every aspect of its context. Interaction matrixes were produced. Land users were prompted to consider the affects of each aspect of a development upon each component of the natural, social and spatial environment. For example, 'Soldiers defecating' was included for an EA of a military exercise in a wilderness area. For a road-building project, the component actions would include construction of a site office, removing vegetation, hiring local Labour, stripping topsoil, deflowering local virgins, excavating subsoil, laying a base course, adjusting drainage patterns, and so on forever. It was and remains a bonanza for environmental lawyers and scientists. A distinction can be drawn between:
Finally, in many countries, an inadequate database and lack of trained personnel are likely to be major constraints. Implementation of EIA in many countries faces problems due to:
poor availability and reliability of data;
insufficient training/education in EIA methodologies and in the establishment of appropriate legal and regulatory frameworks and institutional arrangements;
negligence of beneficial impacts in EIA reports;
lack of consideration of alternative sites, technologies, designs, and strategies;
insufficient involvement and participation of all interested and affected parties;
insufficient emphasis on required cost-effectiveness of EIA;
lateness in implementation and lack of follow-up monitoring and evaluation;
e.g., mitigation/adaptation measures which are not affordable or feasible in terms of maintenance requirements or operating costs;
Poor presentation of EIA results.
As regards the Human health impacts have been given minimal attention in most environmental impact assessment (EIA) studies despite the increasing awareness that many projects may have the potential for causing adverse health effects. The need to address human health in EIA studies was recognized in the 1970 National Environmental Policy Act (NEPA) and, more explicitly, in the 1979 Council on Environmental Quality (CEQ) regulations. In this study a generic health impact prediction and assessment methodology for EIA studies was developed and presented. The first phase of this study consisted of establishing the need for such a methodology. A review of 39 selected EISs showed that human health impacts, although not completely ignored, are typically given inadequate attention. Among those EISS that assessed health impacts, only 27% used risk assessment techniques for assessing all the health impacts addressed. This review was complemented with a more detailed analysis of two EISs that used risk assessment techniques. This analysis showed a lack of integration of the risk assessment elements into the overall EIA process. In the second phase of the study the methodology was developed by aggregating principles contained in risk assessment methods as well as in traditional approaches used in EIA studies. The main consideration was that it should be integrated into the unified analytical process that is basic in an EIA study. Consequently, the generic methodology was organized according to the activities conducted in a typical environmental impact study, with these activities linked to such tasks as scoping, impact identification, impact quantification and evaluation, and aggregation with other impacts. The proposed methodology was tested in a generic case study involving a coal gasification complex. This case study showed that the methodology can also be applied to EIA studies.