International Review of Waste Management Policy - Department of ...

61.4 Concluding Remarks on the Literature
A number of points have arisen from the studies reviewed.
1. Estimates of the unit damage costs for individual pollutants appear to increasing
over time. Although there is still some dispute over which methodological
approach is more valid (VSL or VOLY), the suggestion would be that a forward
looking appraisal of pollution might tend towards the use of damage costs at the
higher, rather than the lower end of existing ranges;
2. In addition, the range of pollutants to which damage costs are attributed is
likewise increasing.
3. The unit damage costs for greenhouse gas pollutants are also tending to increase
over time;
4. The pressure to deal with climate change is leading to a lower carbon intensity
associated with electricity generation, and this trend is expected to continue.
Consequently the benefits associated with energy generated from waste are likely
to decline over time.
5. Landfill may sometimes have greater external costs than incineration, but this is
not always the case. A critical assumption is the capture rate for gas assumed at
the landfill, whilst the assumption concerning the avoided source of energy is also
critical;
6. Very few studies have looked at MBT processes, and therefore very few have
looked at the impacts of landfilling pre-treated/stabilised waste;
7. Given points 1 & 2, and with pre-treatment becoming more widespread, there is
no reason to believe landfilling of pre-treated waste is necessarily worse than
incineration from an environmental perspective, at least given the boundaries
within which valuation studies are currently forced to work;
8. Disamenity may also be significant for residual (and other) waste treatment
plants.
To conclude, all these points suggest that especially at the bottom of the waste
hierarchy, the ordering appears to be far from unequivocal from an environmental
point of view. It should be re-emphasised that few CBAs manage to capture all
possible effects, and it is not entirely clear that those that are not captured would, if
included, have only a small impact on the outcomes.
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International Review of Waste Policy: Annexes