This study evaluated the water soluble lead and the transportable lead of artificial lead-contaminated soil amended with phosphate material using water extraction test and unsaturated leaching model test. After the tests, an insoluble lead mineral formed was determined using X-ray diffraction. The application of amendment could suppress the level of water soluble lead and transportable lead in the neutral and acidic contaminated soil containing lead carbonate or chloride. Formation of insoluble lead mineral such as pyromorphite was identified or detected in both of amended soils after the tests. In water extraction test, the suppression level of water soluble lead corresponded to 72.6% of total lead content in soil while the formation level of pyromorphite-lead was lower at 51.6% of total lead content, suggesting that the other mechanism explained the suppression mechanisms of water soluble lead in addition to the formation of pyromorphite. Suppression level of transportable lead was compatible with the formation level of pyromorphite-lead, indicating that dissolved lead was transformed to the pyromorphite through the transporting process in unsaturated soil, which resulted in the lead immobilization.

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 Soil washing is seen as a volume reduction/waste minimization technology for treatment of radiocesium (radio-Cs) contaminated soils. However, little information relative to specific application and potential effectiveness of the soil washing process exists that applies to radio-Cs contaminated soils in Fukushima. The objective of this experimental study was to understand the performance and validity of soil washing for the radio-Cs contaminated soils. Soil washing performance with a trade-off between the removal efficiency of radio-Cs and the volume reduction rate of feed soils was evaluated after an examination of each radio-Cs balance at every stage of soil washing, namely wet-sieving, hydrocyclone, and scrubbing-flotation.
 As a result of this study, following observations were made; 1) the removal efficiencies of cyclone system were at around 70% of radio-Cs, and the efficiencies were greatly improved to 84~87%, when the cyclone system was combined with the scrubbing-flotation system, 2) the sludge volume was slightly increased when the cyclone system was combined with the ‘chemical scrubbing-flotation’. 3) ‘chemical scrubbing-flotation’ was useful for improving the removal efficiencies of radio-Cs as well as minimizing the sludge volume, 4) the treated water was good for reuse, because the radio-Cs was below the detectable level (< 10 Bq/kg), 5) the radio-Cs content of clean products was less than 3,000 Bq/kg as compared to the feed soils of approximate 20,000 Bq/kg, 6) the volume reduction rate of feed soils ranged from 70 to 80%, and 7) most of the organic matter in feed soils was concentrated into sludge cake.
 The above results indicate that the soil washing system with the chemical scrubbing flotation makes it possible to achieve both high removal efficiency of radio-Cs and a high volume reduction rate of feed soils, and can be practically used in Fukushima for remediation of soils.

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 In this paper, the effect of recycling Joumine water reservoir sludge for strength improvement of the bottom of the Ichkeul lake sediment using the natural ecosystem is evaluated, with a focus on the remediation of National Heritage Ichkeul National Park in Tunisia. The goals of strength improvements are to minimize erosion from sea waves and enable marine organism growth. The main conclusions of this study are as follows. 1) The Joumine water reservoir sludge ecosystem can be enhanced by improving sludge strength. 2) A crystallization of the calcite in the Joumine water reservoir ecosystem is promoted by adding urea and calcium chloride. 3) The proposed techniques can be implemented to improve the benthos growth.

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 This paper proposes a method for creating District Metered Areas considering minimization of the life cycle cost (total of a capital cost and an operational cost). To minimize the cost, some mathematical approaches are applied. Our approach considers a distribution pipe network as a graph network model. Under the model, a graph clustering algorithm decides boundaries of DMAs. Then, genetic algorithm decides entering pipes of DMAs and pump heads. We applied our proposed method to a virtual pipe network to construct DMAs. Compared with the case considering only a capital cost, the result obtained by our method reduces the life cycle cost by 9%. Moreover, we tried sensitivity analysis by fluctuating water demands in the network. By this trial, we confirmed that DMAs robust to hydraulic condition can be created by setting high lower bound on water pressure in a network.

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 Integration of a fluorescent protein gene into chromosomal DNA of Cupriavidus necator KT1, which had been used in bioremediation, was examined with a Tn5 transposon vector. The resultant strains were evaluated as prey bacteria in grazing experiments with a flagellate belonging to the genus Spumella found in the natural environment frequently. Each of the green fluorescent genes of ZsGreen and the red fluorescent gene of tdTomato was integrated into the chromosomal DNA of the strain KT1 with a promoter. Results showed that all promoters evaluated were found to be useful to make transformants that can be observed as a single cell under fluorescent microscopy. The integration of fluorescent gene did not cause any significant effect on neither the character of the strain KT1 nor the predation by the flagellate. Two fluorescent colors were successfully used to confirm that a strain mutated had a better capability of surviving under the existence of the flagellate.

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