Environmental risks and impacts - Environmental Deterioration and Contamination: Problems and their Management - page 204

characterization of the impacts by assigning scores to them (along pre-defined crite-
ria) or percentages on a relative scale (compared to 100% being the reference). The
scores or percentages may be based on quantitative characteristics, but the end point
of the assessment is still not an absolute value because we have added “apple to pear,''
resulting in a figure which means neither apple nor pear and has no unit.
Translating this into an environmental problem, for example, we cannot add the
health risk posed by mercury, the meteorological chances of a flood, the socio-economic
impacts of losing a job and the danger a miner faces. However, something that we can
do is put the risk by mercury, the chances of flood and the socio-economic impact on
individual scales and read the percentage of the particular impact's extent. The risk
of mercury may be, for example, an absolute value of 5 if the mercury concentration
equals fivefold of the screening concentration. Probability of flood can be calculated
from topography and meteorological data using known probability patterns or the
statistics of the last 100 years: small floods twice a year, large flood in every fifth year.
As an alternative we can further assess the consequences of a flood. The relevant con-
sequences may be mercury-contaminated sediment is laid down on flood-plain soil,
gardens and residential area, which can be characterized by a quantitative risk value,
damage to homes and furnishing and damage to husbandry, which can be charac-
terized by a monetary value of 5,000. Social-economic impact on the miner can be

evaluated based on a questionnaire filled up by the miner and scoring his answers
using a predetermined score system. The result is, say, 78 points from a maximum of
a hundred. We have fivefold chemical risk,

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5,000 damage and 78% socio-economic
impact, which should be summed up after normalization. The end point of the impact
assessment is the summarized impacts on the miners which can be compared with the
impact on, let us say, the farmers. If one has long-term experience in the application
of an impact assessing system, sooner or later he can develop the skills in interpreting
the result in a useful and relevant way. The criteria of comparability are the use of the
same impacting components and the same scales for the targets of impact assessment.

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4 MANAGINGTHE RISK OF PROJECTS, PLANS AND PROGRAMS

Environmental Impact Assessment (EIA) accounts for all possible positive and nega-
tive impacts that a proposed project may have on environment and on socio-economic
conditions. A project in this sense may be spatial planning, establishment of an indus-
trial facility, the opening of a mine, changing the energy profile in a region, planning
new regional or national regulations, etc.
The output of this kind of preceding assessment represents the inventory of the
ensuing environmental impacts and is used for making the decision whether or not
to proceed with the project. The International Association for Impact Assessment
(IAIA, 2013) defines environmental impact assessment as the process of identifying
the future consequences of a current or proposed action. It includes the process of
identifying, predicting, evaluating and mitigating the biophysical, social, and other
relevant adverse effects of development proposals prior to major decisions being taken
and commitments made (EIA Best Practice, 1999).
EIA requires decision makers to account for environmental scores in their deci-
sions. As the impacts of a project may be innumerable, the spatial and temporal scoping