碳捕集、利用与封存（CCUS）能够有效降低传统能源产业CO2排放量，缓解气候变化。地层中CO2泄漏，作为潜在风险之一，可能改变浅层地下水水质，影响地表动植物生长，甚至危及周围人群安全。为监测CO2是否泄漏至地表并评估泄漏对浅层地下水的影响，进行浅层地下水连续取样十分必要，为此开发了一种新型浅层井CO2监测系统。详细介绍了该系统的构成、工作原理、技术难点应对措施和操作步骤。该系统基于U形管原理：渗入井筒的地下水通过单向阀进入U形管内，而后采用氮气对U形管的一端加压，U形管的另一端得到样品。该系统能连续对地下不同层位（层位数根据实际需求确定）进行取样，为封存现场环境风险预警系统提供组成数据。

Carbon capture, utilization and storage (CCUS), as an emerging technology to reduce greenhouse gas emissions, could mitigate climate change. CO2 leakage as one of the potential risks would influence the quality of groundwater and affect the growth of surface flora and fauna, even threaten the safety of human beings living around. In order to monitor this kind of leakage and estimate the influence of leakage on shallow groundwater, it is necessary to sample the shallow groundwater continuously. Thus, a novel CO2 monitoring system in shallow well is developed. Its composition structure, working principle, countermeasures to technical problems and the procedure are introduced in detail. The monitoring system is based on the U-tube: groundwater permeates into the borehole and flows into the U-tube through a check valve; then a nitrogen cylinder pressurizes one end of the U-tube; the sample is obtained from the other leg of the U-tube. Moreover, the monitoring system is able to sample from different formation layers (the number of formation layer depends on the actual situation). It also provides data for the risk warning system in project.