Radioactive Material Monitoring in the Water Environment (River Sediments)
Radioactive cesium concentrations in river sediments were measured in FY2021 as in the previous year.
A total of 2,014 samples, including 818 samples collected in Fukushima Prefecture and others collected in Iwate, Miyagi, Ibaraki, Tochigi, Gunma, Chiba and Saitama Prefectures and the Tokyo Metropolis, were surveyed.
The survey results showed that concentrations of radioactive cesium detected in approx. 99% of these samples were less than 1,000 Bq/kg (dry).
- Included in this reference material on March 31, 2013
- Updated on March 31, 2023