fiind acoperit apoi cu sol curat si materialele de drum cu o grosie de 0,5-1m.
Radioactive soil to be used in base layer for new roads
The Environment Ministry on Tuesday drew up a basic plan to use soil contaminated with radioactive substances from the Fukushima No. 1 nuclear plant to build roads.
Under the basic plan, tainted soil with relatively low radioactive cesium concentrations of up to 5,000 to 8,000 becquerels per kilogram will be used to form the base layer of roads.
This level will then be covered with uncontaminated soil, asphalt and other material with at a thickness of at least 50 to 100 cm.
By covering radioactive soil with untainted material, the health risk for residents living in nearby areas will be minimized as their annual radiation dose will be kept to 0.01 millisievert or less, according to the ministry.
The ministry plans to launch a verification project in Minamisoma, Fukushima Prefecture, as early as this summer to test the use of contaminated soil as the base material for road construction.
Tainted soil in the prefecture, generated from decontamination work following the March 2011 accident at the Tokyo Electric Power Company Holdings Inc. nuclear power station, will be kept in an interim storage facility near the nuclear plant for final disposal at a site outside the prefecture within 30 years.
The interim facility, located in an area that straddles the towns of Okuma and Futaba, is believed to store up to 22 million cubic meters of contaminated soil. The latest plan will help the ministry facilitate the reuse of contaminated soil within and outside the prefecture to reduce the amount to be transferred to the final disposal site.