FIXED-POINT OBSERVATION AND CHARACTERIZATION OF RADIOACTIVE CS IN SOIL COLLECTED AT KAWASAKI, JAPAN

Area of Science:

• Environmental Science
• Radiochemistry
• Soil Science

Background:

• Fukushima Daiichi Nuclear Power Plant accident released radioactive cesium (Cs).
• Radioactive Cs contamination in soil poses long-term environmental challenges due to its persistence.
• Understanding the behavior and form of radioactive Cs in soil is crucial for remediation strategies.

Purpose of the Study:

• To quantify radioactive Cs concentration in soils at Meiji University, Japan, ten years post-Fukushima accident.
• To analyze the distribution and chemical form of radioactive Cs in these soil samples.
• To assess the persistence and mobility of radioactive Cs in urban soil environments.

Main Methods:

• Fixed-point observation of radioactive Cs concentration in soil samples.
• Analysis of soil samples using sequential extraction to determine the chemical form of radioactive Cs.
• Measurement of activity concentration of radioactive Cs (Bq kg-1).

Main Results:

• Radioactive Cs concentrations in soil samples at Meiji University's Ikuta Campus ranged from 127 to 448 Bq kg-1.
• Ten years after the accident, radioactive Cs was still detectable in the studied soils.
• Sequential extraction indicated that the majority of radioactive Cs in surface soil exists in a poorly soluble form.

Conclusions:

• Radioactive cesium contamination from the Fukushima accident remains in Kawasaki soils a decade later.
• The poorly soluble form of radioactive Cs in surface soil suggests limited mobility but challenges for removal.
• Long-term monitoring and understanding of cesium's chemical form are essential for managing contaminated soils.