The introduction of a strategic environmental assessment requires prediction of the environmental impact atan early stage and for multiple plans. In an environmental impact assessment(EIA) at the program phase, it is important that the prediction be easily made even if it is not very accurate. This paper presents examples of a road project and a power plant project and proposes a simplified method for predicting air pollution. The proposed method calculates the air concentration of nitrogen oxides and particulate matter from emission quantities without yearly atmospheric dispersion simulations. The relationship between the air concentrations and emission quantities is obtained by analyzing the data presented in existing environmental impact statements. This method is advantageous as full-year meteorological observation is not required. The difference in prediction results between the proposed and the current methods was approximately two-fold and depended on the influence of meteorological and other conditions. The proposed method is applicable to screening and evaluation of alternative plans in the EIA and is also useful to the EIA for urgent disaster recovery.

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UV irradiation reactors are used for water treatment by various industrial fields and public water works for the purpose of inactivating pathogens. In order to design the irradiation reactor, it is necessary to grasp emission models and flow models, however, in order to evaluate the reactor, manufacturers must make a real reactor in order to examine performance. The purpose of this study is to develop a design method for UV irradiation flow reactors. The reactor used in this study was an annular type UV irradiation flow reactor with a lamp sleeve on the center of the outer cylinder. The inactivation of Bacillus subtilis spores was examined varying the transmittance of water, and the test results were compared with the analytical results. From the comparison, it is concluded that the diffuse light model is appropriate as an emission model and the laminar and plug flow model is appropriate for a flow model.

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