飞来峡水库坝区环境放射性水平调查

对飞来峡水利枢纽工程前后(1997～2000年)飞来峡水库库区水环境和坝区环境放射性水平进行了调查，测量了水环境介质(包括水、沉积物、水草、鱼、虾等)的放射性水平、大坝及周围居民区环境氡和土壤的放射性水平、飞来峡水利枢纽建设管理局辖区内的两个采石场的7辐射剂量率水平。调查结果表明：飞来峡水库库区水体中天然放射性核素^238U、^226Ra、^232Th浓度在水利枢纽工程前后无明显变化；水库水底沉积物主要是沙，其放射性水平低于库区土壤和岸边泥土；飞来峡水利枢纽工程坝区的环境放射性水平与未施工前比，总体保持在原来的水平；坝区属于放射性水平偏高地区，但不影响居民的居住。

Radioactivity Level around the Dam of Feilaixia Reservoir

Radioactivity level in the vicinity of Feilaixia Reservoir was investigated prior to and post-project. The results shows that the concentrations of natural radionuclides in water from different areas of the Reservoir are at the same level, without significant changes being found prior to and post-project. The dominant sediment in the Reservoir is sand, with lower radioactivity level than in mud and soils on the riverside. The radioactivity level in this area is kept at the background level throughout the period of prior to and post-project.