LHM is the green hydraulic fluid used in the suspension/brake system of Citroen`s.
Is it near the wheel arch or actually dripping over the bottom of the wheel to the ground, if its leaking down the ram/bottom arm or over the wheel it might simply be a split return pipe that is strapped to the inboard side of the hydraulic ram. If you can be more specific about the location of the leak I might be able to help more