The Japanese architectural, engineering and general contracting firm Shimizu Corporation has developed a new technology to reduce radioactivity in demolished nuclear power plants.

The technology is designed to reduce radioactivity in concrete chunks from demolished nuclear power plants to one-hundredth of their original size.

Through extracting radioactive material from disposed concrete chunks, the technology is expected to save both space and money when managing radioactive waste.

Currently, any concrete from buildings that previously housed nuclear reactors at power plants have to be used for landfill under strict control.

Shimizu believes that by cutting contaminated concrete into 8mm pieces before putting the material in high-temperature nitric acid for 24 hours, 1t of concrete chunks produces only 7.4kg of radioactivity, which amounts to less than one-hundredth of the original volume.

Following the process, concrete chunks can reportedly be disposed of as ordinary industrial waste or even recycled as building material.

Practical tests using concrete from demolished nuclear power plants are yet to be carried out and the technology needs to go under review in order to meet safety regulations.