The exposure rates, the distribution of exposure paths and the risk level of BTEX and aliphatic TPH have been evaluated by using Geo-environmental Risk Assessment System. The major exposure paths to the human are different due to the kind of the oil contents. The human are mainly exposed to BTEX from inhalation of indoor air, groundwater intake and crops intake, whereas they are mainly exposed to TPH (C5-12) from inhalation of indoor air. On the other hand, the main exposure paths of TPH (C12-34) are direct ingestion of soil, inhalation of indoor air and crops intake. The leaching concentrations of exposure limit are estimated at 0.03mg/dm³ for benzene, 1mg/dm³ for toluene, 1.3mg/dm³ for xylene and 0.4mg/dm³ for ethylbenzene. In the case of aliphatic TPH, the soil contents of the exposure limit are calculated at 200-40000 mg/kg.

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To understand the seasonal influence of water discharge from a dam on stream benthic animals, biological and environmental surveys were conducted monthly from May 2000 to April 2001 at sites above and below the Okura dam. At the lower site, total population density increased, and Shannon-Wiener diversity index decreased during the month of September and November. This was a consequence of seasonal outbreak of Hydropsyche orientalis, which mainly feeds on Fine Particulate Organic Mater, and FPOM was highly supplied to the tail water in the said period. The Sorenson's similarity index across the dam showed seasonal prevalence in which the level increased from July to September, decreased during November and December, and recovered from January to March.

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Substantiality of environmental education becomes urgent issue for the world sustainable development. International experience and information sharing, improvement through comparison study are important things. Especially cooperation between Japan and China becomes more and more important in the future. For this purpose, it is necessary to grasp the present conditions of environmental education of China, and push forward mutual understanding. This study focused on the transitions of environmental education between Japan and China are compared through the analysis of junior high school geography. The authors found the change in the description of Course of Study and the transitions of environmental education in the textbook, and analyzed the contents of environmental education of China and Japan. As a results, environmental issue by industry is the center of education in China, contents of environmental consideration education is not enough than Japan.

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With the relative value of the quantity of disaster waste calculated by the estimated debris and the amount of garbage total exhaust in annual, the disaster response capacity of public authorities in the huge earthquake disasters was estimated. A numerical simulation model for wide-area cooperative measures in the emergency debris operation was developed. The required period for emergency debris operation with wide-area cooperation by the backyard method on earthquake disaster in the Tokyo Metropolitan area was estimated at 21.6 months. In addition, it was indicated that the required period for debris operation in the huge earthquake disasters was influenced by the wide-area cooperative measures.

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Phytoremediation is one of the environmental rehabilitation techniques that utilize physiological function of plant. In this study, a colum experiment was carried out to examine the reduction of leachate and the migration of pore water by plants. Migration of pore water toward the lower part was restrained by high volumetric water content in root area( G.L.-10cm and G.L-30cm). As a result, the amount of leachate was decreased by vegetation. The vegetation roots relaxed migration of pore water. Lead concentration of pore water and leachate were not changed by vegetation. Restraint and relaxation of pore water migration toward the lower part by vegetation roots is effective for the prevention of lead dispersion.

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A mathematical expression for the purpose of easy understanding of the result of life cycle inventory analysis on a recycling process with its constituent factors was proposed. In this paper, the methodology was described quoting the case analyzing the reduction effect of CO₂ achieved through a plastic recycling system. The amount of CO₂ reduction was described by four factors, (1) the amount of CO₂ associated with procurement and oxidation of replaced materials or fuels, (2) the ratio of the yield ratios, (3) the ratio of the performances and (4) the amount of the additional CO₂. The proposed method of expression was applied to the examples i.e. the recycling of disposed plastic containers and wrapping.

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The hollow composition isolation wall made of concrete and EPS (Expanded Poly Styrene) was investigated to reduce transmission of vibration. A full-scale experiment was conducted with the wall. The vibration was given by free falls of a weight to simulate vibration from construction works and vehicles. Aa for effect on a decrease in vibration, including embedded depth of the composition isolation wall showed the effect of 4.5dB on the average even in about 1/4 of the wavelength 3Hz in the nearby low frequency number of vibration. And, it was found that the range where the diffraction from the end part of the isolation wall didn't affect was within θ=70° behind the wall. Based on the results, a simple method to estimate the reduction of vibration by the composition wall was proposed. The proposed method estimated the vibration reduction well, and it was found that the method can be used to quantitatively estimate the efficiency of composition isolation wall.

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PCBs concentrations in sea water and blue mussels were observed in Seto Inland Sea, and they were in the range from 0.5 to 4.0 ng/L (mean±standard deviation: 1.8±0.6 ng/L) and from 3.1 to 69.8 ng/g-wet (24.0±19.0 ng/g-wet), respectively. PCBs with chlorine substitution at positions of 2,4,5 were highly concentrated in blue mussels, while PCBs with chlorines at 2,3,4,5 were less accumulated. Two QSAR equations which show relationships between logBCF and logK_ow were proposed with application boundary of either equation at 7.5 of logK_ow. Threshold molecular weight of PCBs at which inhibition of PCBs ingestion to mussel happens was shown to be between 360.88 and 395.32 g.

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Many pro-environmental behaviors for reducing CO₂ emission are recommended recently, thus people might choose to behave in some ways. A perceived effectiveness, which is said to influence the behavioral choise, might differ from actual effectiveness. This is because this factor is affected by various cognitive bias. We therefore supposed the hypothesis that providing information of actual effectiveness would lead to decrease the difference between perceived and actual effectiveness, and then this difference would make pro-enviromental behaviors more efficient. The reduce of difference by providing information is supported by the data analysis of this experiment.

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