In both countries, municipal waste statistics are accumulated through official annual surveys covering all local authorities (ca.400 in England, and ca.3200 in Japan). The extent of inaccuracies and inconsistencies in the statistics is investigated, and recommendations for improvement are made. In many cases, it is possible to detect the cause of inconsistency, enabling corrections to be made to the dataset. Statistical analyses are conducted using the corrected data. Difficulties include the heterogeneity of the units (local authorities) and the large variance in the variables. It is demonstrated that contradictory results can be produced, depending on the statistical method employed.
More intensive analysis reveals interesting information about the six local authorities with the best recycling figures. Many of the selected cases indicated problems with the calculation of recycling rates, but in all cases much effort has been put into recycling and/or waste minimisation. In Japan, some schemes in rural areas relying on recycling and composting are being stretched beyond their limits by urbanisation and the increase in non-recyclable waste. In England, high recycling performances have been achieved by a range of methods and arrangements.
Waste composition data is useful in assessing the potential of various policy initiatives for waste minimisation and recycling. As policies higher up the waste hierarchy are pursued, compositional data with more detailed categorisation is desired. In this research, household waste in Cambridge, UK and Neyagawa, Japan was manually sorted into more than 100 categories. This is possibly the first time that a detailed composition analysis has been carried out in different countries using a virtually identical method. This permitted identification and comparison of the potential for various measures in both England and Japan. It is indicated that due to differences in waste composition, similar policy measures can have very different potential in different locations.