Mining under LakesGo to google maps and have a look at the Athabaska basin. Southern Sask is all prairie and Northern Sask is mostly lakes [ over 100000 lakes] If you don't deal with lakes, you don't mine up there. The area will be the Saudi Arabia of U308 eventually, and dealing with the shallow lakes is not a major problem. In fact it helps with exploration because of easy access to drill sites.
Cameco has had issues with water at the Cigar Lake mine but it was not surface water that was the problem.