The Yenisei River, one of the largest rivers in the world, is contaminated with artificial radionuclides released by a Russian nuclear facility producing weapon-grade plutonium, which has been in operation for many ye...The Yenisei River, one of the largest rivers in the world, is contaminated with artificial radionuclides released by a Russian nuclear facility producing weapon-grade plutonium, which has been in operation for many years. Examination of Yenisei River sediment samples revealed the presence of artificial radionuclides typical of radioactive discharge from the Mining-and-Chemical- Combine (MCC) nuclear facility: isotopes of europium (152Eu, 154Eu, and 155Eu), cesium (137Cs and 134Cs), 60Co, 90Sr, and transuranium elements. The MCC is also a source of radioactive particles in the Yenisei. New data on radionuclide concentrations in sediments and radioactive particles in the Yenisei River were obtained using a wide range of analytical methods. Sequential extraction performed on samples of sediment cores showed different degrees of potential environmental availability of artificial radionuclides and uranium. In a few samples, 241Am was present in the unextractable form, which may be accounted for by the presence of microparticles of the reactor fuel. These microparticles were investigated using scanning electron microscopy, and their reactor origin was confirmed.展开更多
Discharges from the Mining-and-Chemical Com- bine (MCC) of Rosatom, downstream from Krasnoyarsk-26, near of the Krasnoyarsk resulted in radioactive contamination of sedi-ments of the River Yenisei. The concentration o...Discharges from the Mining-and-Chemical Com- bine (MCC) of Rosatom, downstream from Krasnoyarsk-26, near of the Krasnoyarsk resulted in radioactive contamination of sedi-ments of the River Yenisei. The concentration of artificial gammaemitting radionuclides (137Cs, 60Co, 152Eu, and 241Am) was determined to analyze the migration processes leading to the transport of these radionuclides. The concentration of artificial radionuclides in the surface layers of the studied area varied in wide ranges: 137Cs – 318 - 1800 Bq/kg, 60Co – 87 - 720 Bq/kg, 152Eu – 12 - 287 Bq/kg and 241Am – 6 - 76 Bq/kg. There was a sequence of migration of radionuclides investigated in the surface layer of sedi-ments that were collected in the near zone of influence of the MCC: 241Am ≈ 152Eu >60Co >137Cs. Radionuclide species have been found to be directly related to sediment structure and composition.展开更多
The results of monitoring the radiation-chemical situation in the middle reach of the Yenisei River located in the nearest zone of the influence of the Mining and Chemical Combine of Rosatom have been described in the...The results of monitoring the radiation-chemical situation in the middle reach of the Yenisei River located in the nearest zone of the influence of the Mining and Chemical Combine of Rosatom have been described in the paper. Using different physico-chemical methods, it has been found that uranium and tritium content in the water exceeds the background values of the flood plain of the River Yenisei. It has been shown that a wide range of radionuclides of different genesis flows into the waters of the Yenisei River. It has been demonstrated that radionuclides are transported by the water flow in the form of molecular solution or with suspended matter. In this case, the suspended matter consists of pelitic finely dispersed mineral particles, plant and organic detritus and living biological objects （for example, worms）. It has been shown that the main contribution to radionuclide and metal accumulation is made by humic substances covering the panicles of the suspended matter and actively participating in the formation of complexes with radionuclides and heavy metals. As a result of this work, the artificial radionuclide inflow into the ecosystem of the River Yenisei has been evidenced.展开更多
文摘The Yenisei River, one of the largest rivers in the world, is contaminated with artificial radionuclides released by a Russian nuclear facility producing weapon-grade plutonium, which has been in operation for many years. Examination of Yenisei River sediment samples revealed the presence of artificial radionuclides typical of radioactive discharge from the Mining-and-Chemical- Combine (MCC) nuclear facility: isotopes of europium (152Eu, 154Eu, and 155Eu), cesium (137Cs and 134Cs), 60Co, 90Sr, and transuranium elements. The MCC is also a source of radioactive particles in the Yenisei. New data on radionuclide concentrations in sediments and radioactive particles in the Yenisei River were obtained using a wide range of analytical methods. Sequential extraction performed on samples of sediment cores showed different degrees of potential environmental availability of artificial radionuclides and uranium. In a few samples, 241Am was present in the unextractable form, which may be accounted for by the presence of microparticles of the reactor fuel. These microparticles were investigated using scanning electron microscopy, and their reactor origin was confirmed.
文摘Discharges from the Mining-and-Chemical Com- bine (MCC) of Rosatom, downstream from Krasnoyarsk-26, near of the Krasnoyarsk resulted in radioactive contamination of sedi-ments of the River Yenisei. The concentration of artificial gammaemitting radionuclides (137Cs, 60Co, 152Eu, and 241Am) was determined to analyze the migration processes leading to the transport of these radionuclides. The concentration of artificial radionuclides in the surface layers of the studied area varied in wide ranges: 137Cs – 318 - 1800 Bq/kg, 60Co – 87 - 720 Bq/kg, 152Eu – 12 - 287 Bq/kg and 241Am – 6 - 76 Bq/kg. There was a sequence of migration of radionuclides investigated in the surface layer of sedi-ments that were collected in the near zone of influence of the MCC: 241Am ≈ 152Eu >60Co >137Cs. Radionuclide species have been found to be directly related to sediment structure and composition.
文摘The results of monitoring the radiation-chemical situation in the middle reach of the Yenisei River located in the nearest zone of the influence of the Mining and Chemical Combine of Rosatom have been described in the paper. Using different physico-chemical methods, it has been found that uranium and tritium content in the water exceeds the background values of the flood plain of the River Yenisei. It has been shown that a wide range of radionuclides of different genesis flows into the waters of the Yenisei River. It has been demonstrated that radionuclides are transported by the water flow in the form of molecular solution or with suspended matter. In this case, the suspended matter consists of pelitic finely dispersed mineral particles, plant and organic detritus and living biological objects （for example, worms）. It has been shown that the main contribution to radionuclide and metal accumulation is made by humic substances covering the panicles of the suspended matter and actively participating in the formation of complexes with radionuclides and heavy metals. As a result of this work, the artificial radionuclide inflow into the ecosystem of the River Yenisei has been evidenced.
