2021 Volume 2021 Issue 8 Pages 29-34
In paddy fields contaminated with radioactive substances and where planting is prohibited, high concentrations of radioactive substances have accumulated in the top 2 - 3 cm of the soil. The removal of topsoil is therefore a fast and reliable decontamination measure. However, it is difficult to control the removal thickness with commonly-used construction machines. This prompted us to develop a modified construction machine in which the removal thickness is more accurately controlled to ensure full decontamination. The first step in the method is to treat the thin surface soil with soil hardener, consisting mainly of MgO. The second step is to scrape off the thin surface soil by laterally moving the bucket of an excavator. The final step is to suck up the removed soil with a vacuum. This method allows for effective decontamination of radioactively contaminated topsoil with a smaller amount of soil removed.
