秦山核电基地外围环境放射性水平20年监测结果

浙江省辐射环境监测站对秦山核电基地外围环境放射性水平的20年监督性监测结果表明，秦山核电基地外围环境 γ 辐射剂量率，气溶胶中总α、总β、⁴⁰K、¹³⁷Cs的活度浓度，沉降物中总β日沉降量，空气中¹⁴CO₂活度浓度，陆地淡水（饮用水、湖塘水、井水）中总α、总β、⁹⁰Sr、¹³⁷Cs的活度浓度，土壤中 γ 核素²³⁸U、²³²Th、²²⁶Ra、¹³⁷Cs的比活度，生物样品中放射性核素⁴⁰K、¹³⁷Cs、⁹⁰Sr及¹⁴C的比活度，均未发现异常，与对照点监测值和运行前本底调查值相比，属同一水平。空气、雨水、地表水、饮用水、排放口海水和陆生植物样品中³H活度浓度均高于相应对照点监测值，部分介质中³H活度浓度远高于基地运行前相应的本底。说明秦山核电基地20年的运行，特别是秦山三期重水堆运行之后，其外围环境已受到基地流出物中³H排放的影响。

Monitoring Result of Radioactivity Level in External Environment Around Qinshan NPP Base During Past Twenty Years

In the past twenty years, a continuous supervision monitoring of environmental radioactivity level around Qinshan NPP (QNPP) Base was carried out by Zhejiang Province Radiation Environmental Monitoring Center. The monitoring results show that the γ radiation dose rate around QNPP Base, the activity concentration of gross α, gross β, ⁴⁰K , and ¹³⁷Cs in aerosol samples, the gross β daily settlement in fallout, the activity concentration of ¹⁴CO₂ in air, the activity concentration of gross α, gross β, ⁹⁰Sr , and ¹³⁷Cs in environmental freshwater (drinking water, lake water and well water), the average-specific activity of ²³⁸U, ²³²Th, ²²⁶Ra , and ¹³⁷Cs in soils, and the average specific activity of ⁴⁰K, ¹³⁷Cs, ⁹⁰Sr , and ¹⁴C in edible plants, are not abnormal. The radionuclide contents in those samples are of the same levels compared with the background values before the operation of QNPP Base and the monitored values of Hangzhou reference site. However, the activity concentrations of ³H in air, rain water, drinking water, pond water, sea water of discharge site, and terrestrial plants are higher than the monitored values of Hangzhou reference site, and in some medium the activity concentrations of ³H outclass that of background around QNPP Base. The results indicate that after 20 years operation of QNPP Base, especially after the third phase heavy water reactors operation commercially, the external environment around QNPP Base has been affected by ³H in radioactive effluent.