Somewhere along the line, this shot ended up in my inbox, and I'm not able to find who sent it. It looks familiar and you can find pictures of the mill in the Lac La Belle history by Clarence J. Monette. The mill was located on the hill to the right as you take the right fork when entering Lac La Belle.
Some ruins probably remain.
That mill was built by the Delaware Mining Company to process the rock for the mine where tourist now visit. By Bill P.,Ca. Yes,it could be the east corner of the lake where the little stream below Haven Falls flows in. The area between the water and the trees looks like the marsh area and stampsand that was very pronounced before the marshes were cleared and trees started to grow into the stampsand area. It doesn't fit completely in my memory but that's my first thought when I saw the picture.