济南微堆退役场址的终态检测  

Final Survey of Decommissioning Site for Jinan MNSR

作　　者：张永保[1] 李义国[1] 彭旦[1] 邹淑芸[1] 鲁谨[1] 张金花[1] 

机构地区：[1]中国原子能科学研究院反应堆工程研究设计所,北京102413

出　　处：《原子能科学技术》2013年第9期1599-1603,共5页Atomic Energy Science and Technology

摘　　要：采用γ谱测量和低本底β谱测量的方法对济南微堆退役场址中137Cs、60Co、65Zn和90Sr的放射性水平进行了终态检测。所有样品中均未检测出65Zn;水池中60Co的最高值在原堆芯正下方的池底,达49.3Bq/kg,由中子活化而产生;其他检测单元中,137Cs、60Co和90Sr的最高值分别为5.7、6.8和8.1Bq/kg,分别出现在运输通道、堆厅和土壤中,这些核素可能为退役活动污染所致。检测结果表明:所有样品的放射性水平均低于基于年有效剂量为10μSv所导出的清洁解控水平和可接受水平,其中大部分样品接近本底水平。检测方法对137Cs、60Co和65Zn的探测下限分别为1.1、1.0和1.3Bq/kg,检测结果的不确定度小于33.0%,标准物质GBW08304a的测量值与标准值的相对偏差小于3%。Radioactive levels of 137Cs, 60Co, 6SZn and 90Sr in decommissioning site of Jinan MNSR were surveyed finally by detecting 13 and 7 spectra. 65 Zn in all samples was not detected. In reactor pool, the highest level of 49.3 Bq/kg of 60Co exists at pool bottom just below the reactor core, and is produced by neutron activation. In other survey units, the highest levels of 5.7, 6.8 and 8.1 Bq/kg of 137 Cs, 60 CO and 9o Sr exist in transport passage, reactor hall and soil, respectively, and probably come from contamination of decommissioning practice. The survey results indicate that radioactive levels in all samples are lower than the clearance levels and the acceptable levels derived from the effective dose of 10 μSv/a, and that in most of samples are close to the background levels. The detection lower limits of 137Cs, 60Co and 6SZn are 1.1, 1.0 and 1.3 Bq/kg, respectively. The uncertainty of survey results is less than 33.0%. The relative deviation between the measured value and the certified value of standard material GBW08304a is less than 3 %.

关 键 词：济南微堆 退役 终态检测 

分 类 号：TL943[核科学技术—辐射防护及环境保护]