>On the one hand, these holes would be vertical, which is harder than horizontal I don't think this is the case. We dig vertical holes all the time for wells,

>On the one hand, these holes would be vertical, which is harder than horizontal I don't think this is the case. We dig vertical holes all the time for wells, geothermal, and pilings for buildings: http://www.bdonline.co.uk/Pictures/web/r/r/g/CCTV_17_foundation_ready.jpg http://www.bdonline.co.uk/Pictures/web/r/r/g/CCTV_17_foundat... Look at all of them! For one building!