引绰济辽工程文得根引水隧洞放射性调查评价

对长约70 km引水工程洞线上进行的地面伽马能谱测量、陆地伽马剂量率测量、土壤氡浓度测量、岩石表面氡析出率测量以及钻孔岩芯样品的放射性元素U、Ra、Th、K含量分析的综合放射性地质调查，并对获得的测量数据进行分析研究。结果表明，测区引水沿线地质体放射性核素当量含量平均值为：U 1.56×10-6，Th 14.12×10-6，K 2.16×10-2；钻孔岩芯放射性元素分析含量平均值为：U 32.34 Bq/kg，Ra 35.68 Bq/kg，Th 35.29 Bq/kg，K 865.65 Bq/kg。陆地伽马剂量率为90.42 nGy/h；土壤氡浓度平均值为4 272.1 Bq/m3；岩石表面析出率平均值为4.01×10-2 Bq/m2·s。根据测量结果，利用内照射和外照射辐射剂量计算了对施工人员造成的辐照剂量为0.759 mSv，低于国家对公众的剂量限值1 mSv/a，表明引水工程输水隧洞的施工在安全辐射范围内。

Radioactivity survey and evaluation for the Wendegen diversion tunnel of Chouer to Liao River project

Based on the comprehensive radioactivity survey for the chosen diversion project tunnel line, several measurements and analyses were carried out, e.g. the ground gamma ray spectrum measurement, ground gamma dose rate measurement, soil radon concentration measurement, measurement of radon exhalation rate on rock surface, and content analysis of radioactive element uranium, radium, thorium and potassium for the drillcore samples. The results showed that the mean value of radionuclide content of the geological bodies along water diversion tunnel line are:U 1.56×10-6,Th 14.12×10-6 and K 2.16%. The mean value of radioactive elements in drillcore are:U 32.34 Bq/kg,Ra 35.68 Bq/kg,Th 35.29 Bq/kg and K 865.65 Bq/kg. The ground gamma dose rate is 90.42 nGy/h, the mean soil radon concentration is 4 272.1 Bq/m3, and the average radon exhalation rate of rock is 4.01×10-2 Bq/m2·s. The possible irradiation dose to the construction personnel is 0.759 mSv, which is calculated from the irradiation and the radiation based on outside and inside measurements, the results showed that the radiation levels of the survey area were lower than 1 mSv/a, which is the national dose limit for the public, indicating that the construction of water conveyance tunnel of water diversion project is in the safe radiation range.