Why not do both? If a trench is constructed, something must be done with the dirt and rocks. If this is piled immediately in front of or behind the trench (depending on the need), the trench's usefulness is effectively doubled.
Since the J-Probe is wheeled, it won't take a very deep trench to obstruct its progress, just a steep-sided one. I would recommend placing the leftover dirt behind the trench. This would cause the J-Probe to face a near vertical obstruction. If the wall is placed on the opposite side, the J-Probe will be able to scale the wall and then fall into the trench, leaving it INSIDE the perimeter, possibly undamaged and upright.
I would also suggest that we select an area to secure and begin a series of concentric trenches, with small, non-aligned gaps to allow our probes to get through. These gaps could then be mined and/or booby-trapped with rockslides. (Despite the current terrestrial brouhaha over landmines, they still are *very* useful items.) This could also be done with clear conscience since it is defensive in nature only.
What do you think?
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