Soil remediation technologies for removal, decomposition, and confinement of contaminated materials

The effects of various chemical substances on the Earth's environment have become a critical issue in recent years, giving rise to a strong need for technologies to restore contaminated sites. Toshiba is promoting the development of soil remediation technologies for the removal, decomposition, and confinement of contaminated materials, taking advantage of its radioactive waste disposal technologies cultivated through its experience in the nuclear field. These include (1) SARRY-Soil^TM, a technology using an oxalic acid solution to remove radioactive cesium (Cs) from soil, whose effectiveness in offsite decontamination work has been verified through the treatment of soil contaminated as a result of the accident at the Fukushima Daiichi Nuclear Power Station; (2) a technology to decompose volatile organic compounds (VOCs) in contaminated soil and groundwater using a persulfate compound and an iron-based catalyst, which makes it possible to perform processing within a short time; and (3) a technology using magnesium oxide minerals as insolubilizing agents to confine fluoride and arsenic in widely contaminated soil so that they are not eluted into groundwater. (author)