Introduction and principles - Introduction to Environmental Impact Assessment - page 7

development of renewable energy). EIA to date has generally been used for individual
projects, and that role is the primary focus of this topic. But EIA for programmes, plans
and policies, otherwise known as SEA, is currently being introduced in the European
Union (EU) and beyond (Therivel 2004, Therivel & Partidario 1996, Therivel et al.
1992). SEA informs a higher, earlier, more strategic tier of decision-making. In theory,
EIA should be carried out first for policies, then for plans, programmes, and finally for
projects.
Risk assessment (RA) is another term sometimes found associated with EIA. Partly in
response to events such as the chemicals factory explosion at Flixborough (UK), and
nuclear power station accidents at Three Mile Island (USA) and Chernobyl (Ukraine),
RA has developed as an approach to the analysis of risks associated with various types of
development. The major study of the array of petrochemicals and other industrial
developments at Canvey Island in the UK provides an example of this approach (Health
and Safety Commission 1978). Calow (1997) gives an overview of the growing area of
environmental RA and management and Flyberg (2003) a critique of risk assessment in
practice.
Vanclay & Bronstein (1995) and others note several other relevant definitions, based
largely on particular foci of specialization and including demographic impact assessment,
health impact assessment, climate impact assessment, gender impact assessment,
psychological impact assessment and noise impact assessment. Other more encompassing
definitions include policy assessment, technology assessment and economic assessment.
There is a semantic explosion which requires some clarification. As a contribution to the
latter, Sadler (1996) suggests that we should view “EA as the generic process that
includes EIA of specific projects, SEA of PPPs, and their relationships to a larger set of
impact assessment and planning-related tools”.
1.3 The purposes of environmental impact assessment
1.3.1 An aid to decision-making
Environmental impact assessment is a process with several important purposes. It is an
aid to decision-making. For the decision-maker, for example a local authority, it provides
a systematic examination of the environmental implications of a proposed action, and
sometimes alternatives, before a decision is taken. The EIS can be considered by the
decision-maker along with other documentation related to the planned activity. EIA is
normally wider in scope and less quantitative than other techniques, such as cost-benefit
analysis (CBA). It is not a substitute for decision-making, but it does help to clarify some
of the trade-offs associated with a proposed development action, which should lead to
more rational and structured decision-making. The EIA process has the potential, not
always taken up, to be a basis for negotiation between the developer, public interest
groups and the planning regulator. This can lead to an outcome that balances the interests
of the development action and the environment.