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redefined. Because the assessment of site- and region-dependent damage endpoints
is an issue that more or less started in the mid-1990s, not much data have been
published. Therefore, it is quite possible that determined indicators or cost types are
not available in the literature for the processes and pollutants of certain regions.
If data are available, then whether a classification is possible according to
technology and/or region must be determined for each process. If one or both options
are possible, then technology- and/or region-dependent factors from the literature
are used to estimate the corresponding damage. For instance, data on external costs
are available for electricity production (kWh) in regions of Spain. Another example
is the mentioned region-dependent impact factors, e.g., in YOLL, published by
Krewitt et al. (2001) for different European countries and some world regions. If a
classification according to technology and/or region is not possible, then uniform
world factors must be applied. For instance, Rabl et al. (1998) have published a
uniform world model for air emissions. Diesel production and the related process
chain that takes place all over the world is an example of a process difficult to classify.
Depending on the selected weighting scheme and the available data in the
literature, physical impact parameters, damage indicators or environmental costs are
obtained. The physical impact parameters can be summed up directly with those
obtained in the site-specific and site-dependent assessment. Damage indicators and
environmental costs can be gathered together according to the selected intermediate
aggregation scheme. Options for site-specific impact assessment are explained in
Figure 6.15 for the medium of air; in principle, these can also be applied to other
media. For example, Schulze (2001) presents site-orientated impact assessments for
the medium of water in relation to LCAs for detergents, using the integrated assess-
ment model GREA-TER in an adapted version valid for products instead of chemical
substances.
Based on the data of local air emissions, site-specific factors are calculated for
the predominant pollutants. These factors can be expressed in the form of physical
impact parameters before being weighted and aggregated according to the scheme
chosen in the goal and scope definition. The fate and exposure analysis can be carried
out in a generic or detailed way. The generic way uses an integrated impact assess-
ment model, e.g., EcoSense (described in Chapter 4). Such an integrated impact
assessment model consists of a Gaussian dispersion model for the pollutant transport
near the emission point (i.e., approximately £100 km) and another transport model
for the long-range pollutant transport (i.e., approximately >100 km). In the case of
EcoSense 2.0, the models included are ISCST-2 and WTM. The integrated impact
assessment model EcoSense also includes an elevated number of dose–response and
exposure–response functions that can be used for the consequence analysis. The
level of detail in the database of an integrated impact assessment model is limited,
e.g., the resolution of population densities is not as detailed as it could be when
using a geographic information system.
In the case of a more detailed assessment, only the long-range transport model
of the integrated impact assessment model is used (e.g., WTM in EcoSense). An
independent Gaussian dispersion model (see Chapter 4) is applied (e.g., ISCST-3 in
BEEST) for the transport near the emission point and more detailed geographic data
like those in ERA provided by a geographic information system are employed.

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