Environmental Impact Assessment - Mining and the Environment: From Ore to Metal - page 82

against 'science i ction' and 'crystal ball inquiries' in discussing his i fth principle. This
states that the time frame should be realistic and 'reasonably' available within the time the
decision-maker intends to act ( Table 2.2 ) .

Evaluate the 'No Action' Scenario for Comparison

To judge mining-induced environmental change an understanding of the 'no action' scenario
is important. What would happen to the host environment without the project? This is by no
means an easy task. Environments are constantly changing. Natural environments are driven
by the forces of nature which include solar energy, wind, rainfall and runoff, and many other
factors, none of which is constant over time. Ecosystems do not have simple equilibrium states;
they are constantly changing in response to changes in the physical environment and evolu-
tion. Individuals, communities, societies and civilizations also change with time. If the mine
project were not undertaken, the environment would still exhibit: (1) irreversible trends due
to a combination of natural or human-induced factors such as logging, land use changes, or
economic development; (2) irreversible trends of natural origin such as soil erosion or eutroph-
ication of lakes; (3) great variability due to daily and annual cycles, variation in weather, or
natural ecological cycles; and (4) constant changes in host communities (SCOPE 5, 1975).
Elaborating on the 'no action' scenario provides an insight into environmental changes
that would occur in the absence of the project. As mentioned above this is, difi cult and
necessarily involves a degree of speculation as the scale of future changes can not be accu-
rately predicted.
The environmental impact assessment needs then to identify and evaluate environmen-
tal change as a result of the project over time, relative to the dynamic 'no action' baseline,
as illustrated schematically in Figure 2.3 . It is doubly difi cult to predict with any pretence
of accuracy the effects of proposed project actions on an environment whose attributes and
properties are changing continuously.
As monitoring plans are designed to evaluate actual mine-induced environmental
changes during mine operation, the environmental action plan needs to incorporate moni-
toring at environmental and social control locations outside the inl uence of the mining
project, to enable measurement and evaluation of environmental changes that occur which
are unrelated to the project.

Elaborating on the 'no action'
scenario provides an insight
into environmental changes that
would occur in the absence of
the project.

It is doubly diffi cult to predict
with any pretence of accuracy
the effects of proposed project
actions on an environment
whose attributes and properties
are changing continuously.

Focus on the Main Issues, both Negative and Positive

An EIA should not attempt to cover too many topics in too much detail, but should focus
on the most likely and most serious potential environmental impacts. It is as important to
evaluate positive impacts as to assess negative ones. Otherwise it is not possible to assess
the overall or net effects. Large, verbose, complex reports are unnecessary and often coun-
ter-productive, as i ndings are not readily accessible. Mitigation measures should take the
form of workable, acceptable solutions to key issues. The EIA should be communicated
concisely, preferably including a non-technical summary of information relevant to the
needs of decision makers. Supporting data should be provided separately.

It is as important to evaluate
positive impacts as to assess
negative ones.

Use of Environmental Assessment to Improve Project Design

An EIA supports decisions about project design. If started early enough, it provides informa-
tion to improve conceptual design such as with the siting of mine infrastructure, including