Shallow borehole mining waterjet cutting reach-radius test

Since measurements of a BHM stope require special equipment and procedures, an easy and quick beforehand jet-cutting test is recommended, similar to the one pictured below:

In this case, the tool is positioned atop the production interval with the hydromonitor lowered to a short distance below the surface. A jet typically takes a few minutes to get through the ore (no rotation required) and reach the surface (in this case 26 FT away). This test provides a quick glimpse into the BHM possible cutting reach-radius - one of the most important parameters of borehole mining.

Note: the powerful jet gushing from beneath the surface suggests that the jet's energy is not fully exhausted. Thus, lowering the tool deeper in the ore may result in a longer (than 26 FT) cutting radius.