Depends on what your ground looks like. If it's bedrock at the surface and you'd have to dynamite to clear a large patch, then drilling a small hole will be muc

Depends on what your ground looks like. If it's bedrock at the surface and you'd have to dynamite to clear a large patch, then drilling a small hole will be much less expensive and much more efficient. If it is just plain brown dirt for miles down, then digging some trenches might be a better solution. If it's a few feet of sand until you hit the water table, then I have no idea what the best solution is.