The chemical properties of sweet potatososeipaper and barleysoseipaper were determined by the ratio of N, P₂O₅, K₂O, and C in eachsoseipaper. A mineralization test of organic nitrogen was carried out under 30°C the condition in the dark, keeping the moisture content at 60% of the maximum water capacity in the soils. Furthermore, this research was applied to the growth test of Green Pakchoi in a pot made ofsoseipaper.
Results clarified the following :
Mineralization patterns of both types ofsoseipaper show similar changes, but the content of NO^-₃-N varies with the elapsed time.
In the Green Pakchoi growth test using a pot made ofsoseipaper, the plant absorbed components of the sosei paper, which proved to be effective as a fertilizer.
N.B, soseipaper (‘sosei’ means‘reborn’)
SPWS (sweet potato waste stillage)
BWS (barley waste stillage)

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A large number of video-tape-cassettes (videotapes) have been produced in Japan. They will be disposed of, and a new ploblem of waste disposal may occur if videotapes are replaced by other recording media. It might already be necessary to establish a method of processing videotapes. To use materials and parts of videotapes after processing, they must be separated by crushing or disassembly. In this study, six types of videotape processing methods were considered, in which both crushing and disassembly were combined at the different processing stages. Afterwards the volume of CO₂emission and recycle-cost were estimated. The results of this study show that the most environmental friendly and profitable method from the viewpoint of CO₂emission and recycling cost was to crush videotapes directly and to remove materials. If the disassembly time could be reduced less than 53% compared to the present, the CO₂emission volume might be the same as with the crushing method.

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A ‘Resource recycling society’ (RRS) is the common goal to reduce environmental impact from human activities and to conserve natural resources. Its original definition is, however, stated just qualitatively, and it has wide implications. Quantitative indicators are necessary to explicitly show objectives, and to evaluate the achievement level gained by political or technological strategies.
In this paper, focusing on solid waste management in a municipality, six indicators are designed to give RRS ratings, which include evaluation of public attitude concerning waste reduction or recycling as well as grading solid waste management by local governments. Each indicator is made up of there or four questions that are supposed to be answered by citizens. Questionnaire surveys were carried out in thirteen metropolitan cities in Japan. The resulting graph-charts of indicators well describe the different attitude among these cities. Influential strategies towards RRS have been found in correlation analysis, frequent recyclable-collection and regular distribution of pamphlet about waste.

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The collected volume of household waste is a key index of municipal solid waste management because it equals to the volume that a municipality should treat or dispose of. This paper tried to determine why volume differ widely among cities.
The thirteen largest cities in Japan were surveyed. First, statistical data of solid waste collection, both the total volume in each municipality and the volume in administrative districts, were analyzed. Second, questionnaires were sent to residents in six administrative districts in four cities, asking 1) monthly generation of packaging waste, such as bottles and cans, and newspaper/magazines, and 2) disposal method of waste items. Waste flow in surveyed districts was estimated.
Major findings were : per capita waste generation is almost uniform among cities or administrative districts. Acceptance of business/commercial waste in household waste collection simply increases the collection volume. Low collection volume in Hiroshima is due to the wide practice of home-composting/incineration and recycling, and also to strict exclusion of business/commercial waste.

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Estimation methods of waste generation from building demolitions were examined, and demolition waste generations in the near future (including hazardous wastes) were estimated in Japan as a whole. Conclusions are as follows : 1) estimation methods of building demolition corresponding to existing statistics data and changes in building life span were improved ; 2) statistics values for wastes from building demolition could be underestimated ; and 3) demolition waste generation was estimated to be doubled in 2010 as compared to those in 1990, with generation from non-wooden buildings being larger than those from wooden buildings due to the increasing generation of concrete waste, and CCA-impregnated wood and vinyl chloride wastes will increase rapidly, estimated to become 3 times in 2010 as much as those in 1990.

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Conventional equations to estimate sampling variability in leaching tests and content tests are insufficient because these equations are based on the assumption that wastes consist of a single composition. In this paper, the influence of the variability of sampled compositions on the variability of test data of multicomposition wastes, which consist of plastics, fabrics, metals, etc., has been statistically analyzed. Results show that the equations that estimate the coefficient of variation of sampling were derived as functions of sampling weight, particle diameter, average apparent density, which could be measured easily, and a newly defined sampling parameter, which represented a diversity of compositions and was inherent to waste. Using the derived equations, the coefficients of variation of test data for some typical weights, numbers, distributions of particle diameter and average apparent densities of samples were estimated and discussed.

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