When average devices can not get to far enough or function quickly sufficient, Mighty Probe is the tool for the job

https://alexishphs947.cloudhinter.com/posts/just-how-to-find-a-septic-tank-fast-with-a-mighty-probe-and-septic-probe-rod

When ordinary tools can not reach far enough or function fast sufficient, Mighty Probe is the device for the job, offering you the depth, rate, and control needed to get it done.