Baseline radiological environmental monitoring and impact assessment of radioactive waste storage facilities in Thailand

Radiation monitoring was conducted at two sites of the RWSF in Thailand. The activity concentration of tritium was assessed in the surface water, while gross alpha/beta radioactivity levels were measured additionally in soil and sediment. Gamma-ray spectroscopy was obtained the radioactivity concentrations for all environmental samples, and the external gamma-ray exposure dose rate was estimated. No tritium activity was detected at either site and showed no influence from nuclear-related activities. The average gross alpha/beta levels were found to be low, approximately 0.06-0.50 Bq/L, indicating that these levels are within safe limits. The activity concentrations of K-40, Th-232, and U-238 radionuclides in soil samples were 239.38±21.75, 57.95±1.56, and 50.34±0.56 Bq/kg, respectively, while those in water samples were 17.15±1.31, 0.69±0.13, 0.32±0.05 Bq/L, respectively. These natural radionuclides do not exceed the recommended limits. Related artificial radionuclides, including Cs-137, Co-60, and I-131 were not detected in any sample. Additionally, no radionuclides were detected in airborne dust samples, possibility of effective air ventilation in the sampling area. Moreover, the external gamma-ray exposure rate approximately 0.3-0.5 μSv/h, within the natural background radiation level. This routine monitoring has been strictly in accordance with international regulations, confirming that the RWSFs pose no radiological risk to nearby living organisms.