Yes Lebanon is on the other side of the valley. The track leading off to the north goes near the base of the mine.
Hall tunnel was intended to be a link to the mines on guenilla pass, bringing the ore down vertically in a connecting shaft with all the other mines to the hall tunnel, and out to the railroad (this was long before the argentine central had even been imagined). But after striking rich silver veins, they changed course. Kevin wilcomb who works at the loop knows the history of the mines better then I do. If your ever around and curious, he is a great source of information.