某尾矿库周边水放射性分布特征及其评价

Radioactivity Distribution Characteristics and Evaluation of Water of Tailings Periphery

分别测定某铀矿尾矿库排放水、渗滤水及浅层地下水样的放射性核素的比活度,估算周边居民直接饮用浅层地下水中放射性核素所致剂量并评价其影响。结果表明,研究区尾矿库排放水、渗滤水和浅层地下水中238 U的放射性比活度平均值分别为5.80、8.10和2.38mg/L,226 Ra的放射性比活度平均值分别为1.55、2.95×10-1和5.68×10-3 Bq/L。2种放射性核素所致的总待积有效剂量为0.961mSv,比参考水平高出约一个数量级。研究区的地下水放射性水平超标严重,饮用水不安全。

Radionuclide specific activities of discharge water, percolating water, and shallow groundwater of tailings periphery were measured respectively. Nearby residents drink water directly from shallow groundwater, whose radionuclide doses were estimated and evaluated. The results show that radionuclide specific activity of 238U in discharge water, percolating water, and shallow groundwater of tailings periphery was 5.80, 8.10 and 2.38 mg/L respectively, and radionuclide specific activity of 226 Ra was 1.55, 2.95 × 10^-1 and 5.68× 10^-3 Bq/L respectively. Two kinds of radionuclide lead to the total effective dose of 96.1 mSv, approximately one order of magnitude higher than reference levels. The groundwater in study area is unsafe to drink as its radioactivity levels seriously exceed the according standard.