Skipperud Lindis, Salbu Brit, Oughton Deborah H, Drozcho Eugeny, Mokrov Yuri, Strand Per
Norwegian University of Life Science, Department of Plant and Environmental Science, Isotope Laboratory, P.O. Box 5003, 1432 AS, Norway.
Health Phys. 2005 Sep;89(3):255-66. doi: 10.1097/01.hp.0000165449.06373.b0.
The Mayak Production Association (Mayak PA) was established in the late 1940's to produce plutonium for the Soviet Nuclear Weapons Programme. In total, seven reactors and two reprocessing plants have been in operation. Today, the area comprises both military and civilian reactors as well as reprocessing and metallurgical plants. Authorized and accidental releases of radioactive waste have caused severe contamination to the surrounding areas. In the present study, [alpha]-spectrometry and inductively coupled plasma-mass spectrometry (ICP-MS) have been used to determine plutonium activities and isotope ratios in soil and sediment samples collected from reservoirs of the Techa River at the Mayak area and downstream Techa River. The objective of the study was to determine the total inventory of plutonium in the reservoirs and to identify the different sources contributing to the plutonium contamination. Results based on [alpha]-spectrometry and ICP-MS measurements show the presence of different sources and confirmed recent reports of civilian reprocessing at Mayak. Determination of activity levels and isotope ratios in soil and sediment samples from the Techa River support the hypothesis that most of the plutonium, like other radionuclides in the Techa River, originated from the very early waste discharges to the Techa River between 1949 and 1951. Analysis of reservoir sediment samples suggest that about 75% of the plutonium isotopes could have been released to Reservoir 10 during the early weapons production operation of the plant, and that the majority of plutonium in Reservoir 10 originates from discharges from power production or reprocessing. Enhanced 240Pu/239Pu atom ratios in river sediment upper layers (0-2 cm) between 50 and 250 km downstream from the plant indicate a contribution from other, non-fallout sources.
玛雅克生产协会（玛雅克PA）成立于20世纪40年代末，为苏联核武器计划生产钚。该地区总共运行过七座反应堆和两座后处理厂。如今，该地区既有军用反应堆也有民用反应堆，还有后处理厂和冶金厂。放射性废物的授权排放和意外泄漏对周边地区造成了严重污染。在本研究中，采用α能谱法和电感耦合等离子体质谱法（ICP-MS）测定了从玛雅克地区捷恰河水库及捷恰河下游采集的土壤和沉积物样本中的钚活度及同位素比值。本研究的目的是确定水库中钚的总存量，并识别造成钚污染的不同来源。基于α能谱法和ICP-MS测量的结果显示存在不同来源，并证实了近期有关玛雅克民用后处理的报道。对捷恰河土壤和沉积物样本中活度水平和同位素比值的测定支持了这样一种假设，即大部分钚与捷恰河中的其他放射性核素一样，源自1949年至1951年间向捷恰河的早期废物排放。对水库沉积物样本的分析表明，约75%的钚同位素可能是在该工厂早期武器生产运行期间释放到10号水库中的，且10号水库中的大部分钚源自发电或后处理排放。工厂下游50至250公里处河流沉积物上层（0 - 2厘米）中240Pu/239Pu原子比的升高表明存在其他非沉降源的贡献。
