For the purpose of applying Life Cycle Assessment (LCA) methods to the planning and design of infrastructure, relevant data was collected and analyzed and a method developed for environmental impact assessment. Firstly, information on ten varieties of environmental loads used in the construction and maintenance of infrastructure was compiled using the input-output method to produce a life cycle inventory. Secondly, a method for environmental impact assessment of wastewater treatment facilities was developed by normalizing environmental loads to provide a common scale, thus making possible the comparison of environmental severity in different environmental impact categories. A case study of wastewater treatment facilities, including inventory analysis, was undertaken. From this study, an environmental impact assessment for a typical wastewater treatment facility was carried out and comparable values to be used in the planning and design of such a facility were proposed. Examples of the application of the developed method are also presented.

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The authors developed an advanced recycling technique which uses coarse grain material, which is gotten by calcinating for 1 hour at 1000°C after dehydrating construction waste and granulating, for gravel drain material. In this paper, we evaluated about the use for which it is possible to use, except the gravel drain material, this calcined material. As the result, it confirmed that calcined material is possible to use for the roadbet, reclamation, back-filling materials, aggregate which doesn't too much need the strength such as the mortar, and ground material for plant.

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Spatial conformity between heat demand and waste heat supply was analyzed in Tokyo with GIS. For the regional feasibility study on the district sewage heat supply, the relationships between demand and supply, and the probability of heat use were classified. In case that heat pumps were settled at 3 points along an each series of sewer line, the percentage of total usable heat and the usable heat per a heat pump were analyzed as indicators representing the characteristics of the relationships between demand and supply in each series of sewer line. The result showed a high feasibility in Shibaura Sewage Treatment District in the central business district of Tokyo.

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Demolition wood waste recyclings as fuels and boards were evaluated by LCA, and more appropriate method to evaluate CO₂ reduction measures was discussed. Conclusios are as follows: 1) recycling as fuels reduces many environmental loads, which can be further reduced by improving chipping process; 2) recycling as board chips increses some environmental loads in input, which can be reduced by improving chipping process and operating selective demolition; 3) recycling as boards increses many environmental loads in input, which can be reduced by improving glue and board production processes; and 4) CO₂ reduction mesures are evaluated more appropriately by distinction of CO₂ whose origin is biomass from CO₂ whose origin is fossil fuel.

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In this paper, we examine the validity of pulse count of snapping shrimps for sea environmental monitoring. Snapping shrimps exist everywhere in the World Sea, and they make peculiar strong pulse sounds. Pulse count can be achieved merely by recording their sounds for a few minutes by using a hydrophone without special biological knowledge. From field surveys and laboratory experiments, we found that the pulse count depends on water temperature when sea environment is normal, and it falls by the occurrence of oxygen-deficient water. The results show that this method can be a useful index of the effect of water pollution on benthic animals in fixed-point observation.

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Atmospheric dispersion considering plume rise was predicted using a Lagrangian particle dispersion model. The governing equations of the model are stochastic differential equations which represent the random motion of a particle. The vertical component of the equations includes an acceleration term due to buoyancy. Lidar observations of plume rise and field tracer experiments were conducted at a power station to examine the validity of the results from the dispersion model. Good agreement was obtained between the dispersion model and the Lidar observation of the plume trajectory. The calculated result of the spread of the plume was slightly larger than the observed one. This is reasonable considering that the former represents the time average while the latter represents the instantaneous value. The dispersion model was applied to the prediction of concentrations in a real terrain and its validity was verified through comparison with the results of the field tracer experiment.

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The treatment performance and operational parameters of the process, which was composed of pre-coagulation-sedimentation tanks, biofilm reactors and an aerated filter, were discussed with the pilot plant treating actual municipal sewage. Concentrations of SS, T-ATU-BOD, T-N and T-P in the effluent were kept less than 5mg/L, 5mg/L, 3mgN/L and 1mgP/L, respectively, under total hydraulic retention time (HRT) of 8h in the biological process. In the aerated filter, removal of residual organic matter and SS, and restoring DO concentration could be accomplished. The process was proved to be applicable to advanced treatment of municipal sewage without a secondary sedimentation tank.

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The middle-phase microemulsion potentially for oil recovery is often produced by using alcohol as a co-surfactant. The objective of this study is to connect the changes of this middle-phase with the resulting minimum interfacial tensions upon adding the alcohol to the systems containing brine, an anionic surfactant and different alkanes. The results demonstrated a reduction in the interfacial tensions with either increasing alcohol concentration or decreasing the alkane carbon number. The observed trends were expressed by a simple correlation between the minimum interfacial tensions and optimal salinities. This correlation can be used to select the optimum surfactant/alcohol formulations for soil remediation.

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Effectiveness of waste reduction and influence upon other environmental loads and costs were evaluated in two actual old house renovation cases. Conclusions are as follows: 1) waste reduction was observed by around 20% in the case of renovating at the same spot (case A), and a few % in the case of renovating at the different spots (case B); 2) not only waste but other environmental load reductions were observed by a few %-30% in the case A, and a few %-20% in the case B; 3) cost reduced in the case A and increased in the case B, and this implies the possibilities of cost reduction although it is said that old house renovation is expensive; and 4) the system that makes it possible to stock the recyclable materials and to reuse them at appropriate house renovations and constructions is necessary to rise the effectiveness of waste reduction.

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