In order to tackle perceived environmental problems, it is essential to have a good grasp of the facts and figures related to the issue. In waste management, it is often pointed out that the information currently available is inadequate. The UK Department of Environment states that "accurate knowledge of the quantities and composition of waste is fundamental to the provision of efficient, economic and environmentally sound waste management services". As for waste reduction target, it acknowledges that "it will be necessary to improve our data on waste arisings before an appropriate target can be identified" (DoE 1995). Indeed, "data strategy" is one of the main pillars in the UK waste strategy.
While the researcher in his PhD study also looks at the quantity data, the focus of this article is on efforts to grasp the composition of household waste. In earlier studies, analyses in terms of materials (paper, plastics, metals, etc) were carried out. These aimed to determine landfill and incineration characteristics. The need for greater waste categorisation increases as policies higher up the waste hierarchy are pursued. In order to formulate packaging regulations, recycling schemes, and waste minimisation initiatives, not only the material characteristics, but also the social context of the waste becomes important (e.g. is it goods or is it packaging? Where was the packaging being added?).
In England, Warren Spring Laboratory has undertaken waste composition analysis surveys in a number of cities and rural districts, with up to 40 sorting categories. In Japan, Kyoto City Council has been conducting annual surveys of 250 categories for the past 20 years. ARPA-K Co. Ltd, to whom the survey work was contracted out, has conducted similar surveys in numerous Japanese cities.
It is very interesting to compare the situations in various cities in different countries under diverse conditions and waste management systems. Policy insights can be obtained from these case studies. An accurate comparison of the detailed waste composition is very useful in order to assess the feasibility of various schemes in these different locations. Currently, the data to make this kind of comparison possible is lacking. Even when survey results are available, it is difficult to compare one with another, because of the differences in survey methods and categorisation of waste.
The researcher have been involved in a research project which makes international comparison possible. The research project is lead by Professor Kazuhiro Ueta (Economics, Kyoto University), and is funded by the Japanese Government. The ultimate aim is to suggest policies and systems for reduction of packaging waste. In the project, household waste composition surveys were carried out in Neyagawa (Japan, September 1998), Cambridge (UK, November 1998), Freiburg (Germany, December 1998), and Aarhus (Denmark, September 1999). To a certain extent, logistical practicality dictated the choice of cities, but the locations have interesting contrasts. Japan and Denmark incinerate a high proportion of household waste, whereas the UK and Germany rely on direct landfilling. With regard to packaging waste regulations, Germany is known for the DSD ("green point") system, and there is a ban on canned beverage containers in Denmark.
In each city, a total of about 1000 kg of household waste from three housing types (typically; "detached", "terraced", and "flats") was sampled, and hand-sorted into more than 100 categories, following the method developed by Fukuoka and Koizumi (ARPA-K). In order to grasp the total of what is discarded from households, the contents of separate collections for recyclables, and recycling "banks" were also investigated (returnable bottles with redemption value are not included in this survey).
Data analysis is currently ongoing, and the results have not yet been finalised. Interim figures, however, show that the percentage (weight based) of packaging in total discards is not very different in each city: Freiburg 23%, Neyagawa 23%, Cambridge 25%. An examination of the packaging material indicated that plastic dominates in Neyagawa, while glass contributes greatly to the weight of packaging in Cambridge and Freiburg. In a breakdown of stages of added packaging, Cambridge has most from the manufacturing stage, and Neyagawa, a significant amount originating from the retail stage.
The survey results also indicate the potential recyclablility and the actual materials recycling rates. Neyagawa recycles a good percentage of what can be recycled under its current scheme. In Cambridge, a larger proportion of what could go to the recycling collection points ends up in the waste bin. In Freiburg, it is shown that the DSD scheme effectively diverts waste packaging from landfill sites. It is also possible to calculate minimisation potentials from the survey results - the amount of items for which efforts can be made by the industry (eg, packaging, junk mails) and the consumer (eg, disposable items, unused food, etc.).
![[photo: all from bins]](collage.jpg)
The survey results will probably provide good PR materials for waste
minimisation and recycling. The sheer amount of unused food makes it manifest that we do indeed live in a wasteful world.