The resistivity fish counter is widely used in Europe to count Atlantic salmon that pass through in-river structures (e. g., a Crump weir). The use of the counter is known to be an accurate and economical way of counting fish. However, the counter is rarely used in Japan. This study aims to establish a method for counting fish that pass through a fish way in Japan by using the resistivity fish counter.
 A platform equipped with the sensor component of the resistivity counter was assembled in the fishway at the headwork of the Tone-ozeki. We designed the platform in accordance with the requirements of a fish way for Atlantic salmon (i. e., with appropriate velocity and height of water flow). We counted the number of salmon passing through the fish way during the spawning season by using the resistivity fish counter on the platform.
 The sensor component of the fish counter was captured by a video camera from directly above, for a total of 19 h. The number of fish was counted from the video analysis. The accuracy of the number of salmon determined by using the fish counter was evaluated by comparing the result obtained from the fish counter with that obtained from the video analysis.
 The accuracy of the number of salmon counted by using the fish counter was found to be 96%. The factors that might decrease the accuracy of the counter, the method of designing the platform in accordance with the requirements of a fish way, and cost for this study were considered. Methods for improving the accuracy of the counter are discussed.

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 The high loading rate oxidation ditch (OD) system with dual dissolved oxygen (DO) control has been developed for the purpose of advanced wastewater treatment and cost saving. For the purpose of scale-up to the real scale, the clean water experiments were conducted, with the full scale oxidation ditch with diffused aeration and vertical flow boosters, to examine the effect to the dual DO control by the design and operational factors, which include a flow characteristics and a oxygen supply capability.
 In this study, the flow characteristics of the OD channel were analyzed using a tank number and circulation ratio as the parameters. The analysis showed the complicated flow characteristics of the OD channel, which changed from the plug flow to the completely mixing transiently. Based on the tank number N =65~100 which were obtained from the tracer tests, a model of DO mass balance was constructed, then the accurate method for estimate the overall oxygen transfer coefficients was proposed. The potential error of the conventional method in the specific conditions was indicated. In addition, the effect of the flow characteristics on the design and operational parameters of the dual DO control, which include the circulation time or the DO profile, was clarified.

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 In this study, we developed an integrated management model that supports local government to make a promising energy saving measure on a block-scale combined with urban planning. We applied the model to Osaka city and estimated CO₂ emissions from the residential and commercial buildings to 2050. The urban renewal cases selected in this study included advanced multipole accumulation case, normal multipole accumulation case, and actual trend continuation case. The energy saving options introduced in each case included all-electric HP system, micro grid system, and we also set the option where the greater CO₂ reduction one is selected in each block. The results showed that CO₂ emission in 2050 would be reduced by 54.8-57.6% relative to the actual condition by introducing the new energy system in all cases. In addition, the amount of CO₂ reduction in actual trend continuation case was highest. The major factor was that the effect of CO₂ emission reductions by installing the solar power generation panel was higher than the effect by utilizing heated water mutually on the high-density blocks in terms of total urban buildings' energy consumption.

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 We have studied how the fluorine-insoluble in the waste foundry sand (chromite sand) and production method of the roadbed material with insolubilized waste foundry sand. And we got following knowledges.
 (1) We found a minimum mixing rate to insolubilize of fluorine in the waste foundry sand by the ingenuity of mixing procedure.
 (2) Now we can insolubilize the waste foundry sand including comparatively high concentration fluorine (elution concentration: 20-70mg/l) by the mixing time difference of MgO and blast furnace cement.
 (3) In the verification test the roadbed material made from the insolubilized waste foundry sand satisfied reference value of environment safety.

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 The purpose of this study, we use the material that mixed plural wastes from a viewpoint of the effective use of the wastes as planting ground, is scrutiny of the practicality as the materials and be the proposal of the environment and landscape evaluation method of the slope seeding. The soil hardness of the materials are in the range of 15-23 proper mm in the vegetation from the observation result for about 4 years after the slope planting execution and for instance, the C/N ratio changes with 33 or less we have obtained the fine value to growth of the vegetation. In other words, the practicality as planting ground is able to be proven from a viewpoint of the effective use of wastes. To the next, we choose the color of slope seeding and we replace it to the reflectance that is used since before, we grasp the color like the numerical value from the vegetation reflection spectrum and from green visibility ratio we propose the method that the environment and landscape evaluation of slope seeding is predicted. As the result, the method that we propose can become 1 method that the environment and landscape of slope seeding is predicted objectively, the purpose of this study is able to be achieved.

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 A tool for strategic development and improvement of remediation technologies was proposed to set a target specification by applying the RN_SOIL, an evaluation index of remediation technologies for contaminated soil. Under the scenario of agricultural site contamination with dieldrin and its remediation, improving items and the target values of the bioremediation using charcoal material (charcoal bioremediation), as a developing technology, were determined. The development target was that the RN_SOIL value of charcoal bioremediation fell below that of high temperature thermal desorption as a competing technology. Sensitivity assessments of the RN_SOIL selected a remediation period and an incubation volume for bacterial growth and settlement in the charcoal as improving properties. Risk assessment and life cycle inventory analysis was introduced to determine a human health risk due to contaminant, and a total cost of remediation or a CO₂ emission accompanied with remediation, as evaluating factors of RN_SOIL, respectively. Assessment based on the RN_SOIL was able to show clearly improving items for achieving the target or items with great effect for improvement.

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 The results of forecasting domestic water demand in the long term are important for planning water supply facilities and operation and management systems. In Japan, recently, domestic water demand has been decreasing because of the progress of a water saving society such as spread of water-saving equipment. The trend methods has been used for forecasting water demand, however, water demand structures are complicated due to the variation of factors affecting them. It has therefore become difficult to forecast domestic water demand by the trend methods. Some waterworks have used multivariate analysis method using quantification method theory 1 for water demand forecasting. However, the method includes a issue not to be able to set in the changes of prescriptive factors in the future. The selection of explanatory variables is also a large issue. The aim of this study was to analyze changes of the prescriptive factors using quantification theory type 1 by the results of questionnaire surveys carried out at intervals and to reflect how far the water demand should be expressed on practical level focused on the selection of explanatory variables. As the results, changes of the factors and its contribution were revealed across the age. However, results of the water demand forecasting were not enough accurate because of the changes of factors. And, the considerations in water demand forecasting using multivariate analysis were mentioned.

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 There were the following typos in the article, "Journal of Japan Society of Civil Engineers, Ser. G (Environmental Research) Vol.67 (2011) , No.3 pp. 134-149".

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