ducks guts, page-4

I think your comments on the dewatering are off the mark. Pumping the lake down using electric pontoon mounted pumps is one thing, dewatering ground water is another. Handling rain events using sumps yet another. Dewatering the dig face allows better drill & blast (not that these guys need that yet) better grade control, less dilution and mining loss, better pit floors for trucks..... Also it provides better wall geotechnical factors of safety. Anyone who has looked at a retaining wall sees drainage holes to "depressurise" the wall for geotechnical stability.