I would think they would be mobile units. The drill here is a helicopter portable rig, they consist of about 13, 2000lb lifts not including fuel, drill rod...etc. The drill here is about a 30 min flight from camp. No road access. SLI's drills could be bigger in size as they could be driven there on flatbed and are either moved by Cat by dragging them around or would be mobile units. There is a drilling company I pass on the way to work, just outside of Thunder Bay, they have a number of drill rigs mounted on old Sherman tank chassies.