To promote consumers' pro-environmental behavior, scenario analysis by life-cycle assessment was applied to drinking water usage, the environmental consequences of which depend on usage behavior. First, elements that characterize drinking water usage were listed, and incompatible elements were grouped into five stages: production and distribution of drinking water, water quality improvement/sales of drinking water, storage of drinking water, use of drink containers, and disposal of plastic bottles. The usage of drinking water was described from consumers' viewpoints, and each scenario was identified by selecting a single element as a module from each of the five stages and then combining the modules. Then, greenhouse gas emissions were evaluated with regard to five types of drinking water (i.e., tap water, small and large containers of domestic bottled water, and small and large containers of imported bottled water) and three types of drink containers (i.e., drinking glasses, water flasks, and plastic bottles). Greenhouse gas emission for each module was formulated as a function of the volume of drinking water, then that in a given scenario for a given volume of drinking water became calculable. Greenhouse gas emissions were compared among scenarios consistent with particular situations or tastes of consumers.

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The diffusion and adsorption of benzene in soil are key factors determining the fate and transport of benzene. Therefore, any mathematical model for benzene transport in soil requires appropriate consideration of the diffusion and adsorption processes. In this study, benzene transport models were developed for Andosol and sand, considering diffusion through gas and liquid phases and liquid-solid adsorption, based on experiments using a headspace flux chamber. The liquid-solid adsorption experiments were performed to determine the benzene adsorption coefficients. The results show that the model can predict benzene transport in Andosol and sand in wet conditions. The adequacy of current gas-solid adsorption methods under dry conditions was also studied using sand with a low water content (0.4%). The results indicate that gas-solid adsorption is appropriate for the benzene transport model in sand at low water contents.

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The characteristics of benzene emissions to the atmosphere from two types of soil (sand and Andosol) were investigated using a flux chamber (30.0 × 17.5 × 29.0 cm). Soil was placed in the chamber and air was then flushed through the headspace. The benzene emissions to the atmosphere were estimated under various conditions by measuring the benzene concentrations in the headspace. The results indicated that the benzene emission rates from both soil types decreased with increasing soil moisture content. The emission rate was also affected by the benzene content of the soil. The emission rates from both soils could be described using the benzene dissolution from soil as measured by a water leaching test. The effect of changing the air flow rate from 3.8 to 11.4 hr^-1 through the headspace for sand was clarified, with increased air flow rates resulting in increases in the benzene emission rate. The effect of temperature changes from 20 to 40°C for Andosol was also determined with increased temperature resulting in increases in the benzene emission rate.

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