The first looks like a floating dredge. They probably had a man-made lake there. The last look like some sort of smelters, to melt whatever they were mining out of the ore.
You are right on the first photos and damn close on the second set! The first pick is of the Yankee Fork gold dredge. Pretty heavy machinery operating 24/7 in the late 1800's early 1900's. Even in the dead of winter. The kilns were used to create charcoal to melt down the silver they were pulling out from the Bayhorse mine.