With a bit more processing this would be really good. As it is, you have a sound composition that nails the challenge, and a model who is acting the part well, but the photo remains flat and dull. If you haven't done so, a levels adjustment would bring more depth to the tonal range.
I think you lost a bit of the colors in the left part of the photo (the rocks look a bit washed out compared to the ones on the right, probably because of the light), but I like the colors and textures on the right side of the photo. :).
It looks to me as if the rocks near the foreground are in focus, and the boy is not. Would have preferred a greated depth of field to carry tjhe focus for more of the photo
I am wonder if the trees and grass were cut out if it would look like he was lifting a pile of rocks! Nice idea. Learn to make Curve adjustments to make image pop!
Great shot, I only wish that the model was in a bit clearer view. It looks like the focal point is a bit short of him. A smaller aperture might have been effective here.
The image size isn't the best to say exactly but it seems that the focus is more on the bridge than on the person. The background with the trees is a bit colorless and the sky is burned.