高放废物处置库因格井预选区水化学-同位素分析

Groundwater Chemical and Isotopes Characteristics of the Yingejing Preselected Area for High Level Radioactive Waste Disposal Repository

因格井坳陷是中国高放废物地质处置库黏土岩重要预选场址之一。选取研究区19组水样作为研究对象,利用Piper三线图和Gibbs图等方法,探讨该区域的地下水化学特征和氢氧同位素特征,主要结论是:研究区的地表水和地下水的水化学类型主要是Cl-SO_4-Na-Ca型或Cl-SO_4-Na型,水化学类型差别不大;pH大多落在7~9之间,TDS值均小于100 g·L^(-1),两者符合中国黏土岩选址的基本标准;地下水主要接受大气降水的补给,地表水的补给作用不明显,初步认为,就水文地质条件而言,因格井坳陷预选区适合建造高放废物处置库。

Yingejing Depression,one of the important preselected sites of disposal repository for high-level radioactive waste（HLW） in China,is located in the Bayingobi Basin,Inner Mongolia Automomous Region,northwest China.Based on 19 water samples collected in the study area,using Piper diagram and Gibbs diagram method,the chemical features of groundwater and characteristics of hydrogen and oxygen isotopes are discussed.The main conclusions are as follows：the major hydrochemistry type both groundwater and surface water is Cl-SO_4-Na-Ca or ClSO_4-Na;7 ~ 9 p H and TDS values are less than 100 g/L,which conforms to the basic standard of clay rock site in China;precipitation is the main source of groundwater,surface water supply effect is not obvious.Preliminary view,in terms of hydrogeological conditions,Yingejing Depression is suitable for the construction of high level radioactive waste disposal.