The Luxembourg Sandstone is the main strategic aquifer of the Grand-Duchy of Luxembourg, providing one third of the total drinking water resource in the country. In the unconfined part, the aquifer discharges through more than 400 springs, which are used for supply. The long-lasting diffuse contamination by pesticides (more recently Metolachor ESA) has been previously simulated assuming the aquifer as an equivalent porous medium, and using environmental tracers and baseflow characteristics. A statistical analysis of the whole data set of artificial tracer tests made for this aquifer (112 injections involving 102 springs) emphasized the role of the main fissures (NE–SW) for preferential groundwater flow and the importance of including them in a conceptual model involving a multiple-porosity aquifer. The results show that these fissures are influencing the whole flow system. The average peak velocity is 16 m/h and the average first arrival (maximum) velocity is 52 m/h (32 m/h for injection-well to spring traces alone), with a recorded maximum velocity of 350 m/h. The threats of infiltrating streams within catchments have also been characterized, suggesting the usefulness of tracer tests for optimizing protective measures. The main benefit of the study is the improvement in the ability to delineate safeguard zones accurately, according to more representative velocities and the strong anisotropy.

卢森堡砂岩是卢森堡大公国的主要战略含水层，提供了该国总饮用水资源的三分之一。在无限制部分中，含水层通过400多个用于供应的弹簧排出。先前已经模拟了农药（最近是Metolachor ESA）对农药的持久性弥漫性污染，并假设含水层是等效的多孔介质，并使用了环境示踪剂和基流特征。对该含水层进行的人工示踪剂测试的整个数据集（112次注入，涉及102个泉水）的统计分析强调了主要裂缝（NE-SW）对地下水优先流动的作用以及将其包括在涉及地下水的概念模型中的重要性。多孔的含水层。结果表明，这些裂缝正在影响整个流动系统。平均峰值速度为16 m / h，平均首次到达（最大）速度为52 m / h（仅注入井至弹簧走线为32 m / h），记录的最大速度为350 m / h。还对流域内溪流渗透的威胁进行了表征，表明示踪剂测试对于优化防护措施的有用性。这项研究的主要好处是，根据更具代表性的速度和强各向异性，可以准确地描绘出保护区的能力。还对流域内溪流渗透的威胁进行了表征，表明示踪剂测试对于优化防护措施的有用性。这项研究的主要好处是，根据更具代表性的速度和强各向异性，可以准确地描绘出保护区的能力。还对流域内溪流渗透的威胁进行了表征，表明示踪剂测试对于优化防护措施的有用性。这项研究的主要好处是，根据更具代表性的速度和强各向异性，可以准确地描绘出保护区的能力。