It can turn either way, but why should that matter?
I was looking at a picture of one and figured I could fit a motor to the crank handle. The crank handle would have to be modified, of course. The question about the crank handle turning either way was based on whether the operation of the unloader was accomplished by a continuous turning of the crank as opposed to turning it one way to lift the culvert and the other way to send the magnet back to pick up another culvert.
Basically, if the handle is meant to turn one way to accomplish the entire unloading process, my task would be simpler.