I mixed a harmless salt in water (called a tracer, because it’s easy to detect), and injected it into the ground. Then i used a huge pneumatic drill with a special geophysics tool (measuring resistivity) to chase down where the salt was moving before it diluted too much to find.
Its called a Tracer Test, and it’s pretty common for characterizing aquifers. What made my test unique was proving the usefulness of a geophysics tool to chase down the changes in geochemistry.

Faster, more responsive than installing a network of monitoring wells ahead of time.

I’ve now told you enough that i may have absolutely given my identity away.
Grad level science is a much smaller world than you might think.