The old timers typically washed these areas down to bedrock, and some areas appear terraced. I would imagine this is because these hydraulic mines were generally where the miners found old Tertiary river channels on the sides of mountains that were gold-bearing.

Two potentially important Canadian projects, which could have produced revenues in the billions and jobs in the tens of thousands, have now been officially abandoned and the reasons offered by both relate to the economic impossibility of successfully negotiating all the regulatory obstacles that have been presented.