I have had Scouts employ heavy equipment . . . although briefly, and arranged by the Scout. eg: gas powered post hole digger for hard packed clay and rock for fence posts, and as in this case for the holes for an outdoor classroom. There, there were 9 benches (2 posts each) and a teacher podium (1 post) in hard pack. In another case, a bobcat was used to raise a bluestone slab to door level for easier wheel chair access at an old church. The slab was 5' x 8' and 6 inches thick!! As long as the Scout arranges for it (not Dad) and sees to it that the equipment is used by adults, then it is just like the use of a circular saw or a chop saw to get the job done. Just make sure it's done safely.
Eagle '63, ASM, Council Advancement Comm.(Eagle advisor),OA VIGIL member,NESA, council training staff,