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

at landfill and incineration, but at recycling too. However, very few have looked at
other non-landfill treatments for residual waste. 1144
Some of the key assumptions which influence the outcomes of such appraisals are
outlined and discussed below. This discussion will highlight important methodological
issues, serving to contextualise the subsequent review of specific studies.
61.2.1 Methodological Issues Common to External Cost Appraisal of all
Options
In what follows, issues relating to the calculation of external costs of different residual
waste options are considered. Firstly, a number of general comments are presented
on the methodology applied in studies assessing of external costs.
1) Most studies seem to use an approach based upon the use of unit damage costs
(UDCs) to assess the harm caused by specific pollutants. Relatively few make use
of ‘bottom up’ approaches in which the impact of emissions are modelled through
dose-response functions applied to the locality in which an activity takes place.
2) If the study is ‘top down’, the choice of unit damage costs becomes critical.
Similarly, if the study is ‘bottom up’, the choice of dose-response functions, the
way the dispersion of pollutants is modelled, and the nature of the location
assumed for any activity all become important. The scope of the analysis (the
range of the pollutants modelled) is of obvious significance in both cases. There
do appear to be some discernable trends in this regard:
� The range of pollutants to which a damage cost is assigned appears to be
expanding over time. Earlier studies tended to focus on emissions of GHGs,
NOx, PM and SOx, whilst more recent studies have become more ambitious in
their attempt to capture a range of externalities. A problem here is that neither
the unit damage costs, nor the dose response functions which typically
underpin studies from which UDCs are derived, are known with certainty.
There remains considerable uncertainty concerning the effects of a range of
pollutants upon human health. It barely needs stating that the long-term
consequences of some activities have barely been touched upon;
� The significance of specific types of pollutant in the overall assessment of
damages appears to be changing. GHGs may be becoming more important,
even as the damages associated with SOx, NOx, PM10, etc. are being
downplayed. PM2.5 may become more important in analyses as awareness
1144 J.C. Powell, David Pearce and Inger Brisson (1995) Valuation for Life cycle Assessment of Waste
Management Options, CSERGE Working Paper WM 95-07; Coopers & Lybrand, CSERGE and EFTEC
(1997) Cost-Benefit Analysis of the Different Solid Waste Management Systems: Objectives and
Instruments for the Year 2000, Luxembourg: Office for Official Publications of the European
Communities.); Broome, E., P. Vaze and D. Hogg (1999) Beyond the Bin: the Economics of Recycling,
Final Report to Waste Watch.; COWI (2000) External Costs of Landfill and Incineration, Final Report to
the European Commission; Nolan ITU (2004) TBL Assessment of Garden Organics Management, Final
Report to the NSW Dept of Environment and Conservation, Sustainability Programs Division, May
2004.
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International Review of Waste Policy: Annexes