高放废物地质处置野马泉预选场地 地下水同位素分析

 野马泉地区是我国高放废物处置库的重要预选区之一,大面积分布的花岗岩是良好的处置库围岩。为认识研究区的水文地质条件,从水文地质角度评价其作为高放废物处置库场地的适宜性,开展同位素水文地质调查工作。野外调查和氢、氧稳定同位素分析结果表明,研究区浅部和深部地下水均源自大气降水补给,浅部地下水主要由现代和区内降水补给形成,而深部地下水则可能由区域降水补给形成。此外,地下水的氚含量数据表明,浅部地下水系统相对开启,水循环交替能力较强。

ISOTOPE ANALYSIS OF GROUNDWATER IN YEMAQUAN CANDIDATE SITE OF CHINA¢S HIGH-LEVEL RADIOACTIVE WASTE REPOSITORY

Yemaquan district,one of the important candidate sites for China¢s high-level radioactive waste repository,is located in the Beishan area,Gansu Province,Northwest China. The granite is widely distributed in this district and it will be a good host rock for a high-level radioactive waste disposal repository. In order to understand the hydrogeological conditions and to evaluate if the district is a suitable/unsuitable site for a repository,the isotopic hydrogeological investigation and research were carried out during last decade. According to the field investigation and the analysis of the stable isotopes of hydrogen and oxygen,it is concluded that both shallow groundwater and deep groundwater are of meteoric origin. The shallow groundwater is recharged mainly by modern and local precipitation,and the deep groundwater may be originated from regional precipitation at higher elevation. In addition,from the tritium data of groundwater in the district,it is also found that the shallow groundwater system is relatively open;and the ability of water circulation is more capable than that of deep groundwater system.