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Life Cycle Assessment: Principles, Practice and Prospects
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such outcomes can be foreseen using LCA is, of course, a function of the appropriate scoping
of the study, data and modelling, and constraints of the technique. For example, the study by
Beer et al. (2002) did not take into account land use or water use, as is the case with most LCA
work on biofuels to date internationally. In this case, the practitioners recognised the omission
as a constraint on impact identification.
At first glance, it appears that the pitfall of the already defined question can only be avoided
by explicitly defining or re-defining the question in its systemic context as a first stage within
the LCA. There is an obvious and fair objection to this. Naturally, clients engage LCA with
questions they have already identified, which they need assistance to resolve. If these questions
were not acceptable, LCA would have few clients. That there are boundaries to the questions is
also practical, given limited time and resources, let alone that a bounded question is necessary
to give the process any direction.
The pitfall is not, however, automatic. It can be resolved to the extent to which the LCA is
self-reflexive; that is, to the extent that it recognises that the results are determined by the scope,
method and limitations of the assessment itself. LCA can achieve this in the fourth stage, ‘Inter-
pretation’, where the results of the inventory analysis, duly related to indicators in the impact
assessment, are examined to assess whether they provide a sufficient level of evidence to draw
valid conclusions. The results are tested against each of the three previous steps using a variety
of methods, including sensitivity analysis, completeness checks and data quality analyses. In
referring the results back to the first stage, ‘goal and scope definition’ (see Chapter 3), the objec-
tive of the initial question is revealed and any potential conclusions from the results are
examined to see whether they meet that objective. It may be shown, at this stage, that the objec-
tive is not met by the results because the initial question has not been designed to achieve this.
A well-known example where this process resulted in a recommendation to re-define the
original question was the second major LCA ever conducted in Europe, on biopolymers in the
1970s (Oberbacher et al. 1996). The initial question was about the difference in environmental
impact between plastics made from biopolymers and other plastics, the objective being to rec-
ommend ways to reduce the impact of plastics. The results showed that both sets of plastics
involved considerable environmental impact, and therefore answering the initial question
would not lead to any significant reduction in impact. So the recommendation was that the
more general role of packaging and plastics in the economy should be challenged to see how
their impact could be tackled. Based on a consideration of the context of the problem – the
flow of plastics through the economy – the final recommendation addressed deeper structural
causes of environmental impact and suggested more far-reaching solutions than the initial
question would have allowed.
The following two Australian LCA examples also illustrate how interpreting the context of
the problem or initial question can lead to systemic solutions.

4.3.1 Case study: Yarra Valley Water
Yarra Valley Water, a Victorian water authority, commissioned an LCA to compare the author-
ity’s reticulated water supply system with small household rainwater tanks, to see whether the
tanks should be introduced to save water (Grant and Hallman 2003). The results showed that
the tanks did not compare well with the existing reticulated system. On interpreting the results,
it was realised, however, that it did not make sense to recommend extending the reticulated
system as an alternative to tanks. The existing infrastructure was fixed and could not be
extended, and the results did not point to the existing system being the best available way to
save water. Instead, the initial question was re-defined to take into account the authority’s
objective, and a further LCA compared a range of water-saving mechanisms as possible alter-
natives to reticulated water.

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