My question is, how does this differ from what is currently used to make artificial snow? The wastewater is treated to have the impurities removed, so it's relatively clean. On the other hand, traditional snowmaking operations use retaining ponds at the base of the mountain to hold the water they will use to make snow. Those ponds are typically filled from natural waterways. Those natural waterways have fish, frogs, and other stuff in them. The ponds themselves are lovely habitats for ducks, geese, beaver, etc. Know what all those animals have in common? They all poop. The snowmakers pump the water out of those poop filled ponds, run them through a basic particulate filter (so the sticks and leaves don't clog the gun nozzles), and pump that right out of the guns onto the slopes. Poop is poop. When my students eat the snow, I remind them that the snow is made from poopy water, and they usually stop pretty quick.
It seems like people are more upset about the idea of this operation, rather than the actual quality of the water being used.