that is a 3 million dollar rock miller. Digs 10 feet wide and 2.5 feet deep. Moves on average like 5000 yards of rock a day. Used for milling roads, building pads, and anything else God put in the way. The 3rd picture is a trencor 1760 digs 15' feet wide and up to 7 feet deep. Doesn't move nearly as much rock as my machine.
Been many years now but i wanna say it was out near driftwood....
things were so impressive i pulled over to check out the path
they were carving...'course it was a weekend & they werent runnin'...
i cant imagine how much noise they make chewing up rock...