Radiocesium distribution and mid-term dynamics in the ponds of the Fukushima Dai-ichi nuclear power plant exclusion zone in 2015–2019

Factors Controlling the Dissolved 137Cs Seasonal Fluctuations in the Abukuma River Under the Influence of the Fukushima Nuclear Power Plant Accident

“…In the early stage of the accident, highly radioactive Cs-rich microparticles (CsMPs) were widely dispersed and were observed at the Tsukuba, Japan (∼170 km to the south of the FDNPP). Thus, the trend of decline in K d (=−0.05 years −1 in Figure 2f) could be associated with 137 Cs leaching from CsMPs (e.g., Ikehara et al, 2020;A. Konoplev, Wakiyama, et al, 2021).…”

“…These are caused by physical decay and natural attenuation processes, including advection, diffusion and dispersion, but these processes do not reduce the total amount of radionuclides; rather, they affect radionuclide distribution over space and time, and may dilute radionuclides in the environment or partially remove/relocate and spread them (A. A. Konoplev, Wakiyama, et al, 2021;Smith et al, 2005).…”

Reconstruction of the Long-Term Dynamics of Particulate Concentrations and Solid–Liquid Distribution of Radiocesium in Three Severely Contaminated Water Bodies of the Chernobyl Exclusion Zone Based on Current Depth Distribution in Bottom Sediments

“…The water samples were filtered in situ through sandwich-type Petryanov filters (with a pore size of 0.5 µm) to separate suspended material from solution [48]. Dissolved 137 Cs was immobilized by two sequential cartridges of cellulose-based and iron hexacyanoferrateimpregnated ANFEZH sorbent (EKSORB Ltd., Ekaterinburg, Russia) [10,49,50]. Alternatively, the filtrate was collected into plastic containers and 1 mL of 6M nitric acid was added for direct determination of activity.…”

“…Thirty-five years after the Chernobyl nuclear power plant (ChNPP) accident, studies of radioactive contamination of water bodies continue to be of importance and relevance due to the need to understand long-term processes and dynamics. Closed and semi-closed lakes and ponds were found to be most sensitive to radioactive contamination, as evidenced by numerous studies conducted in the Chernobyl contaminated areas [1][2][3][4][5] and the Fukushima Dai-ichi nuclear power plant zone [6][7][8][9][10], as well as in the PA Mayak area [11][12][13] and in the USA including Savannah River site [14][15][16]. Despite a vast number of studies of radionuclide behavior in such water bodies, most of them lacked broad temporal coverage and did not deal with long-term changes in radionuclide concentrations.…”

Long-term prediction of $$^{137}$$Cs in Lake Onuma on Mt. Akagi after the Fukushima accident using fractional diffusion model

“…Therefore, the 137 Cs activity concentrations of the lake water and pond smelt in Lake Onuma were measured for a long period of 5.4 years after the accident 10 .The main processes governing 137 Cs activity concentration after the accident can be categorized into an initial phase and mid-, to long-term phases, corresponding to the post-accident phase. The most important processes in the initial phase are the atmospheric fallout of 137 Cs on the water surface, subsequent sorption and fixation by sediments, and their settling on the bottom [13][14][15] . Besides pure fitting, a parameter for a given lake and radionuclide in the diffusion model can be estimated using characteristics with clear meaning 137 Cs deposition, effective diffusion coefficient, and distribution coefficient 11 , and thus predictions of 137 Cs long-term dynamics in a lake can be provided immediately after the accident using previously measured values of the characteristics, literature data or expert judgments.…”