Due to increasing pressure on the capacity of landfill sites and the need to reduce environmental impacts associated with management and treatment of waste, (i.e. emission of gases that lead to global warming), many local Japanese governments are currently facing the challenge of tackling the issues surrounding municipal waste management and treatment. Local authorities have also been suffering from increasing fiscal stress as they confront the problem of a population that is shrinking and graying at an unprecedented rate. These are two social phenomena that have serious implications on how municipal solid waste is managed. Given the social and economic changes taking place, local municipalities must explore new methods for the administration and operation of solid waste collection and treatment, while taking into account that limited financial and human resources have to be utilized effectively and efficiently with significant priority on the needs of citizens. This approach would be similar concept to the New Public Management (NPM) system which was originally initiated in the United Kingdom.
According to Barzelay, NPM is “a term used to describe distinctive new themes, styles, and patterns of public service management.” In this article, we focus on ‘benchmarking (BM),’ as a tool for bringing about the general concept of NPM. BM will allow local governments to recognize the positioning or ranking of their own public service performance, and to compare individual performance with that of municipalities having similar social and economic conditions. We explore the potential pros and cons of the BM application for better municipal solid waste management; and conclude that a comprehensive and consistent database is necessary for the effective comparison of local public service performance. Capable human resources with decent knowledge and experience in both municipal solid waste management and the NPM principle will also be critical for effective utilization of BM. A reward system based on the results of BM will require careful mechanism design due to potential inconsistencies between that which should be rewarded and that which can be most effectively rewarded.

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The objectives of this study were to verify the effectiveness in reducing polluting gas emissions of novel methods for covering dairy slurry by using various types of hydrophobic fertilizers and to evaluate the mechanisms for reducing gas emissions from this slurry before and after methane fermentation. The hydrophobic fertilizers were prepared by mixing finely-ground chemical fertilizers (SP: super-phosphate, CC: calcium carbonate, and NP: a mixture of ammonium phosphate and ammonium sulfate) with hydrophobic silica (8wt. %) to make a moisture-proof cover that could float on the slurry. Laboratory trials were carried out for 13 days using a pilot-scale device. The hydrophobic fertilizers composed of SP and NP reduced NH₃ and CH₄ emissions from the digested slurry remarkably. However, we did not observe any suppression of gases when we applied the hydrophobic fertilizer composed of CC. The effect of the novel covers on the emissions of greenhouse gases and other polluting gases varied with the types of chemical fertilizers depending on acidity-alkalinity, solubility and ability to adsorb these gases. The hydrophobic fertilizer coverings and partial dissolution of their nutritional constituents affected the fermentation process of dairy slurry during storage and consequent gas emissions.

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The characteristics of three currently operating kitchen-waste biogasification facilities, including the amounts of methane (CH₄) generated, their environmental burdens, and the economic efficiency of each were investigated. The amounts of CH₄ generated at kitchen-waste biogasification facilitis from untreated kitchen waste and from kitchen waste that which undesirable materials were removed ware 67-92m³_N/ton and 83-103m³_N/ton, respectively. This wade clear that evaluations of amounts of CH₄ generated from kitchen waste should consider CH₄ measurements errors and the ratios of undesirable materials and carbon in the kitchen waste.
We found that concern for reduction of odor emissions was necessary and that the properties of the liquid fermentation residue depended on the change in the weight of the kitchen waste during treatment, the type of methane fermentation system used and the type of pretreatment method used on the liquid fermentation residue at kitchen-waste biogasification facilities.
The amounts of electricity generated by the biogas were less than the total amounts of electricity consumed in the kitchen-waste biogasification facilities. The running costs, not including labor, of a facility that releases treated liquid fermentation residue into the sewage system and treats odor with the ordinary deodorization methods were estimated to be about 7500-9600yen/ton kitchen waste. In a facility that releases treated liquid fermentation residue into a river, treats odor with an advanced deodorization method and adopts a dual-fuel type generator, the running costs, not including labor, were estimated to be about 14500yen/ton of kitchen waste.

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Adsorption characteristics of commercially available charcoal made of phyllostachys pubescens was quantitatively evaluated using the gas phase adsorption method. Micro-pore volume of the bamboo charcoal involved in adsorption is about 0.2mL/g, and has about 30-50% adsorption ability compared to a standard activated charcoal. It is a molecular sieve with a micro-pore diameter of 0.6-0.7nm. A comparison of absorption ratios shows that the micro-pore diameter depends on the temperature the bamboo charcoal is made at.
In conclusion, bamboo charcoal is a high-perfomance, functional material that is easy to produce (just by carbonizing mature bamboo). It also has excellent characteristics from the viewpoints of utilizing unused resource materials and energy consumption. The bamboo charcoal can be applied for the molecular level separation as a cheap absorbent.

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We have developed a Horizontal Permeable Reactive Barrier (HPRB) system as an alternative intermediate and bottom soil cover in landfill. The HPRB materials were prepared by mixing volcanic ash soil (i.e. Kanto loam) as the base material for capturing toxic chemicals, iron powder discharged from foundries as a reaction accelerator, and waste-melted slag as a permeation regulator. In this study, the HPRB performance was evaluated by using four in situ pilot-scale lysimeters in test cells with diameters of 5m and heights of 7m. Two test cells were filled with waste A - an inorganic waste consisting of incineration ash and crushed incombustible waste. Two other test cells were filled with waste B in which 5% compost was added to the waste A. HPRB layers of 0.5-m thickness were placed at the bottom of each 2.5-m-thick waste layer and slag layers were placed as controls in the same manner.
We evaluated them by designing a 2²-type experiment consisting of two-factors (waste and cover soil) and two standards (waste A and waste B, HPRB and slag). 125 chemical items in leachate, including pH, EC, ORP, organic pollutants, inorganic ions, metals (including metalloids), volatile fatty acids and organic compounds (chlorobenzenes, phenols, 1,4-dioxane, PAHs) were monitored over a one-year period. As the result, 60 items were detected in the leachates and, except Ca²⁺, Mg²⁺, NO₃⁻, Zn and 1,4-Dichloro-benzene, the main effect of HPRB was confirmed for all the items. This suggests that HPRB can capture and purify large quantities of these substances.

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This study reveals historical changes in household waste collection service charges following World War II as a basis for studying cost sharing for waste management systems. We reviewed surveys of waste collection charges conducted from post-war times up to the present. Our results showed the following: 1) The number of cities that levied charges for household waste collection services increased from about zero to 50 percent during the first ten years after World War II, but it decreased to about 10 percent in the late 1960’s and early 1970’s. There was another increase starting in the early 1990’s, which reached about 40 percent in 2005; 2) The ratio of charge revenues to municipal solid waste management costs in Japan decreased from about 10 percent to three to four percent in the late 1960’s and early 1970’s; 3) The average charge in 1957 was at 173 yen per household per month (inflation adjusted price). This was about half of what was being paid by households for waste collection in cities with a unit pricing program in the year 2000.

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Ishikawa (1966) introduced Grid City Model (GCM) in order to provide an approximate estimation of the costs for collection and transportation of municipal solid waste (MSW). This paper shows how GCM can be extended using a GIS (Geographic Information Systems) mesh data of the population. The GCM-GIS model offers better estimations for cases with uneven population distributions, or for municipalities that have complicated layouts. Sensitivity analyses were carried out with various patterns of trash separation. Results showed that the eventual times of collection has a greater effect on costs than the pattern itself.

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