2. Selection of target values for selected indicators:
after having selected a set of indicators as explained
before, it is necessary to set favored target values.
To select these values, a hierarchical approach was
followed:
(a) Consideration of the existing Chilean framework,
with respect to targets already set.
(b)For those indicators that the Chilean framework
did not provide targets for, debates with scientists,
politicians, public authorities, waste pickers, and
other stakeholders were carried out.
(c) Finally, data from literature research regarding
values established and achieved, at the
international level, were used as references for
target definition.
3. Identification of sustainability deficits: a comparison
between the current indicator values and the favored
target values (as explained in step 2) allowed
identification of deficits threatening sustainability. The
values of indicators for the current situation were
determined in a previous work [23].
Table 1 shows the most relevant indicators, which have
been selected on the basis of the criteria mentioned above.
The future explorative scenarios of MSW management
are evaluated following the methodology explained in
the ‘Sustainability evaluation’ section. The development
of explorative scenarios is explained in the next
subsection.
Explorative scenarios
One important question is how the management of
MSW generated will look like in the future. If it is possible
to have a look into the future, will it be possible to
take actions today in order to improve that future? The
scenario technique is a key concept for this type of prospective
analysis, describing events and trends as they
may evolve. This technique helps to support decision
makers and policy makers to establish strategies for alternative
futures [25]. Within the Risk Habitat Megacity
Project, three explorative framework scenarios had been
developed for the MRS: BAU, CR, and MI. These framework
scenarios served as a basis for the establishment
of specific scenarios in the field of MSW management
in MRS. The framework scenarios are characterized
by different driving forces for future development; as
a consequence, the three scenarios, at the most general
level, show differences in economic development
(e.g., the increase of the GDP), institutional framework/
governance (e.g., market or state influence), demographics