定量示踪试验在地下水污染防治中的应用——以福泉市龙井湾为例

Application of quantitative tracer test in prevention and control of groundwater pollution——A case study of Longjingwan in Fuquan city

龙井湾岩溶管道地下水系统为研究区主要发育的地下水系统之一。为准确确定岩溶地下水来源、径流方向以及地下水流速和岩溶管道介质特征等,以1 400 g荧光素钠为示踪剂,通过分析接收点试剂历时曲线分析管道结构,计算地下水流速和其回收率。试验结果表明:龙井湾岩溶管道总体为单支岩溶管道,但中间可能串联了多个地下溶潭。烟科所溶洞至龙井湾泉地下水最快流速为22.1 m/h,最慢流速为10.2 m/h,主峰平均速度为18.8 m/d。并通过计算示踪剂回收率,龙井湾岩溶泉(S1)接收点回收率为10%,大井边(S2)接收点回收率为65%。为后期厂区地下水污染防治提供依据。

Longjingwan karst pipeline groundwater system is one of the main groundwater systems developed in the study area.In order to accurately determine the source of karst groundwater,the direction of runoff,the velocity of groundwater and the characteristics of karst pipeline media,1400 g of sodium fluorescein was used as the tracer to analyze the pipeline structure by analyzing the reagent duration curve at the receiving point,the velocity of groundwater and its recovery were calculated.The results showed that the longjing bay for single karst conduit karst pipeline overall,but may have series multiple underground puddle in the middle.The fastest and slowest groundwater velocity from Yankesuo Karst Cave to Longjingwan Spring is 22.1 m/h and 10.2 m/h,the average peak velocity is 18.8 m/d.By calculating the recovery rate of tracer,the recovery rate of Longjingwan Karst Spring(S1) is 10%,the recovery rate of Dajingbian(S2) is 65%.It provides the basis for the prevention and control of groundwater pollution in the later period.