北山花岗岩裂隙地下水循环属性试验研究

 中国高放核废物预选场址位于甘肃省北山花岗岩体中。北山3号试验钻孔(BS03)位于旧井地段，地处区域性地下水系统的径流区。该钻孔是专门为场址评价而开凿的。首次采用钻孔双栓塞水文地质试验系统由该钻孔采集到分别来自144.00～156.77，208.00～238.00，430.51～445.72 m这3个层段的代表性地下水样。稳定同位素(d 2H，d18O)测试分别采用铬还原和CO2平衡法制备并且在MAT253质谱上测试。结果表明，地下水补给为本地降水，与前人关于祁连山补给的观点不同。氚采用蒸馏与电解富集流程(20倍)制备并且在QUANTLUS1220上测试。氟利昂(CFCs)采用带德国制富集装置的气相色谱测试。结果表明，3个层段地下水样品中均不含1951年以来人工热核试验带来的氚或1940年以来人类工业化带来的氟利昂，属于年龄在60 a以上的老水。

EXPERIMENTAL STUDY ON CYCLE PROPERTY OF GROUNDWATER IN FRACTURED GRANITE IN BEISHAN，CHINA

The pilot site for high-level radioactive waste repository in China is located in Beishan granite body of Gansu Province. Test borehole No.3(BS03) is seated in the area belonging to ground run-off zone of the regional groundwater system. The borehole is drilled specially for site evaluation. A group of depth-specific groundwater samples have been obtained for the first time from three different depth levels，i.e. 144.00–156.77，208.00–238.00，430.51–445.72 m in the borehole using a double-packer down-hole sampling and testing system. Stable isotopes d2H and d18O of the groundwater samples indicate that the recharge of the groundwater mainly comes from local precipitation. It is different from the earlier oppinion that the recharge of the groundwater comes from Qilian Mountains. 3H and CFCs contents show that the age of the groundwater at the interested depths is at least 60 years.