Flour mill

[tingeliM]

I like the green tint. It creates a little ominous atmosphere, but maybe turn it down just a little bit? The black and white conversion of yours is quite flat, but that one could look great also.
Be careful with the balance between the shadows and the highlights. Now the waterfall is way too bright and it sticks out too much, in my opinion.
In black and white this is clearly visible and easy to fix when there are only the lights and the shadows to work with. This is why it's always good to check even the color images with a black and white layer while editing to see if anything sticks out too much (especially the stuff that isn't supposed to). Another good technique is to zoom out and/or squint your eyes to see if there is a part of the photo that has too much black or too much white in it.

Here's my black and white version of your image:


I used a black and white gradient map for the conversion. Often times it works well, and then you can selectively use levels or curves adjustment layers to bring out highlight or deepen the shadows.
I used levels adjustment layers to darken the waterfall a little bit and bring out the mill's highlights. I also lightened the sky's light areas a bit with a curves adjustment layer (you might as well use the levels).

And here's the same with a little bit of green tint:


I took the shade of green from your original image and applied it to an empty layer. Then I switched the layer mode into color and lowered the opacity down to 33%.