[pp.43-50]
Tomoaki HACHIMURA, Minoru YAMANAKA, Hiroyuki OHNO, Shuichi NAGAOKA, Tetsuya MIYAHARA and Hiroyuki TOSAKA (Kagawa University / Kankyo Chishitsu Co.Ltd / The University of Tokyo)
Abstract:
Natural disasters occur frequently in Japan, such as the Great East Japan Earthquake. Huge amounts of debris are generated from large-scale disasters; therefore, it is important to appropriately treat and dispose of the debris, which is handled as waste. If such disaster waste is not disposed of in an appropriate and effective way, numerous problems will occur at the final disposal site. For example, disaster waste layers in which stabilization is very slow could become problematic in former site redevelopment. If disaster waste were disposed of directly at a damaged landfill, environmental pollution can be expected. In addition, appropriate disposal of residue and untreatable wastes may be difficult due to the limitation of allowable landfill capacity. In order to appropriately dispose of huge amounts of disaster waste, tentative storage sites are required to be set up at appropriate areas. However, the risk of environmental pollution may be higher at several tentative storage sites. If the tentative storage is expected to be active for a long period such as several years, sufficient and concrete countermeasures such as a hydraulic barrier containing soil mixed with bentonite are necessary. The hydraulic barrier using bentonite is incrementally effective in the treatment of radiation-contaminated waste because bentonite adsorbs radioactive substances.
Key Word:
disaster waste, final disposal site, tentative waste storage site, environmental impact, hydraulic barrier works, bentonite mixture soil