同位素技术在某核废处置场区水文地质条件研究中的应用

本文通过对研究区各类地下水化学成分、水中氢、氧稳定同位素及放射性同位素的研究，区分出浅层地下水（孔隙水）和基岩风化裂隙水。确定了地下水的补给区为排牙山区；地表水、地下水迳流的主要方向为ＳＥ向，同时存在地下水侧向迁移，并以泉的形式补给浅层水和地表水。通过氚的衰变计算及与香港观测站的资料对比，确定了区内地下水的相对年龄，并将其分为３个年龄组：（１）迳流时间最短的地下水，具近期大气降水的氚浓度；（２）相对年龄为２０年左右的浅层地下水；（３）相对年龄大于３０年的低氚水。

THE APPLICAITION OF ISOTOPIC TECHNIQUE TO THE HYDROGEOLOGICAL CONDITION RESEARCH IN A NUCLEAR WASTE DISPOSAL SITE

Through the research on chemical compositions of various kinds of ground water,hydrogen and oxygen stable isotopes and radioactive isotopes in ground water in the study area,theshallow underground water(pore water)and the weathering fissure water in bedrock are distinguished in this paper.It is determined that the recharge area of ground water is thePaiyashan area. The main direction for the surface water and ground water runoff is SEstriking,in the meantime the lateral migration of ground water exists and recharges the shallow water and surface water in the form of springs. Based on the decay calculation of tritiumand compared with the data from Hongkong observation station,the relative ages of water inthe area have been established and they are divided into 3 age groups:(1)ground water withthe shortest runoff time, having tritium concentration identical to that of recent meteoricwater;(2)shallow ground water with the relative age of about 20 years;(3)low tritium water with the relative age of more than 30 years.