高放废物处置系统地下水同位素特征

Isotope Characteristics of Groundwater in the Potential Site of a High-Level Waste Repository in China

在高放废物处置库场地特性评价中 ,对于深地质处置方案而言 ,最有可能使放射性核素进入生物圈的机制是地下水的迁移 ,因此 ,水文地质研究是场址预选和评价中的一个重要内容。本文以甘肃北山预选区旧井地段为例 ,根据地下水同位素数据 ,结合所获得的地质、水文数据和信息 ,分析研究了研究区基岩地下水的起源、形成、演化和循环特征。研究表明 ,北山预选区旧井地段 ,深部地下水和浅部地下水均源自大气降水的补给 ,弱含水、低渗透。

Using the isotope techniques, the authors studied the origin, evolution and circulation of the groundwater in the potential site of China's high-level waste repository. The results indicate that both deep groundwater and shallow groundwater are mainly recharged by modern and local precipitation, and the deep groundwater in the site area is of meteoric origin. The shallow groundwater is mainly recharged by modern and local precipitation, and the deep groundwater originates from regional precipitation at higher elevation, or might be derived from the precipitation during the geological period of lower temperature. It is also known from the study that the deep underground is a system of very low-permeability where the groundwater flow rates are very low.