Soil with high moisture content is often improved using conditioners such as calcium oxide (CaO). However, for bioremediation of such improved soils, the effect of increased pH on indigenous microbes in the soil is a concern. In this study, the effects of various amelioration conditioners on soil pH and microbial count have been investigated in the context of bioremediation. The effect of soil neutralization and addition of nutritional amendments for biological treatment after amelioration, were also discussed. Results clearly indicated that microbial counts in the soil significantly decrease with increased pH resulting from amelioration. However, through soil neutralization and the addition of nutritional amendments, microbial counts clearly recovered to original levels or higher without any addition of new microbes. From the final microbial count and physical and other properties following neutralization, utilization of the neutral soil amelioration conditioners appears to be very effective in terms of bioremediation for ameliorated soil.

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 Deterioration of Municipal Solid Waste Incineration Plants (MSWIPs) is becoming a significant social issue in Japan, especially considering decrease of population, and some plants can be renewed or closed under some circumstances. To make a scheduling for renewal or closure of MSWIPs, we apply the multi-period multi-plant location model by Okubo et al., to the south part of Miyagi prefecture. We examine the stability of the timings and priority of renewals and/or closures against the changes in population prediction, maintenance cost of plants, reconstruction cost, and so on. As a result, under realistic parameter changes and error of population forecasting, renewal and closure strategy are very stable at least first 6 years. On the otherhand, the closure decision and timing of the MSWIPs having later year closure plan may vary due to the parameter change.

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 This study compares the environmental and economic effects of alternative targeting strategies (benefit, cost, and benefit-cost ratio targeting) for reducing nitrate-N water pollution. We apply the three targeting strategies to the Conservation Reserve Program (CRP) in the Des Moines Watershed in Iowa.
 Our results show that the benefit-cost targeting achieves the highest nitrate-N runoff reduction. Although the cost targeting results in the largest amount of land out of production, this strategy also results in the smallest environmental benefits. The benefit targeting takes the smallest amount of resource out of production and results in highest output level. Our results also show that those differences among alternative targeting strategies tend to be larger when budget of land purchasing fund is smaller.

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