A method for conducting simultaneous convergent tracer tests in multilayered aquifers

Area of Science:

• Hydrogeology
• Environmental Science
• Geochemistry

Background:

• Forced gradient tracer tests are crucial for understanding contaminant transport and aquifer properties at the field scale.
• Traditional full-depth tests yield complex breakthrough curves, hindering the identification of specific flow paths.
• Level-specific aquifer tests are often costly and do not guarantee pathway identification.

Purpose of the Study:

• To present a novel method for conducting simultaneous, multilevel tracer tests.
• To overcome limitations of traditional tracer testing methods in identifying subsurface flow pathways.
• To enable high-frequency and cumulative sampling for detailed transport analysis.

Main Methods:

• Development and application of a novel multilevel sampling system for simultaneous tracer tests.
• Conducting forced gradient tracer tests between two boreholes.
• Utilizing fluorescein as a tracer in a multilayered sandstone aquifer.

Main Results:

• Successful simultaneous execution of multiple tracer tests across the full borehole depth.
• Generation of six well-defined tracer breakthrough curves.
• Demonstration of the system's capability for high-frequency and cumulative sampling.

Conclusions:

• The novel multilevel sampling system effectively facilitates simultaneous tracer tests.
• This method significantly improves the ability to delineate groundwater flow paths and study contaminant transport.
• The technique offers a more efficient and informative approach to aquifer characterization.