There is considerable fear of further increase of brown field in Japan because of the growing proportion of elderly population and the fall in land prices. Reduction in cost of counter measures or the securement of remediation quality seem to be urgent matter, however high cost excavation of contaminated soil or the long term pump and treat of groundwater are still chosen at many chlorinated volatile organic compounds (CVOC)-polluted sites. In this research, by using the site case study polluted by CVOC under the existence building, we compared the sustainable approach, which is relatively new evaluation strategy, with risk based approach and cost based approach. Six of countermeasure techniques included excavation, anaerobic biostimulation using vertical wells, in-situ chemical oxidation, anaerobic biostimulation using slant wells, monitoring, pump and treat. It was possible to evaluate the various output parameters of environmental, social, economic aspects by using sustainable approach. Only sustainable approach could compare the risk of remedy works, which include the risk of traffic accidents, with carcinogenesis risk (health risk) of CVOC. In addition, this approach could only estimate the benefit of future land use by attending the profit-earning ratio of land through or after the remedy work of considered six techniques. On the other hand, difficulty of the decision-making by numerous indexes and necessity of an integration index was considered to be the problem of sustainable remediation in the future.

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 A series of studies aims to develop superabsorbent polymer based soil conditioner as new soil conditioner in classification sorting treatment of decontamination soil. In this study, the soil improvement mechanism by superabsorbent polymer based soil improvement material is verified through physical analysis. As a result, the following contents were revealed. (1) Improvement effect by superabsorbent polymer-based soil improving material is remarkable for any target soil, and in case of homogeneous soil, improving effect can be expected more in high water content condition. (2) Superabsorbent polymer based soil conditioner is an improvement based only on moisture absorption of interstitial water. (3) One of the reasons why the classification test results differ between sandy soil and viscous soil is that moisture having a high holding power remains in the viscous soil which can not be absorbed by the superabsorbent polymer type soil improving material, and the aggregate structure is dispersed. It could be thought that it did not reach to.

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 A planting ground which composed of sewage sludge, water supply sludge, waste wood, and wood chip derived from construction of industrial waste as main (raw) material and mixed with flying powder of Konjac to act as adhesives material and plant growth base material which composed of organic growth foundation material mixed with polymer-based resin are experimented by spraying seed on a sloped ground of Toyo university campus. The physical characteristics of soil hardness and water-holding capacity; Chemical characteristics of pH, EC, CEC, and the total amount of nitrogen; ground coverage ratio; and spectral reflection characteristics are calculated for a long term and evaluated the adaptability. As a result, flying powder of Konjac is not inferior material comparing with polymer-based resin and sufficiently act as adhesives material. And also the proposed planting ground as slope stabilized material is feasible for resource recovery. Moreover, the results contribute to promote industrial waste treatment and disposal, and re-cycling them as a planting ground can be capable to restore nature.

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