I own and operate a 2 inch dredge. It is a lot of work, and the deeper the water, the more work it is....I cant imagine running an eight in dredge for more than an hour at a time. So IMO it would take at least four people to run an eight inch dredge for eight hours. Also, 50 tons an hour is very very optimistic, moving water and heavy or course dredging material slows production dramatically. 50 tons an hour at .05 ounce per ton would be great, IMO is optimistic, but lets hope for the best.