Marine4 from here knows the story much better than I do, but there is a story of two children that went missing (traveling back home) and (one or both) found passed away in the area. What was creepy was the youngest was about my son's age (3-4) and while I was walking the lower tunnel, I felt "him" holding onto my boot as I walked along. There was also a collapse in the top tunnel killing I think about 12 workers (you can see where the brick changes).
The mob was also big in the area back in the day, and there are stories that this is one of the locations for kills (the coke ovens are another....belt buckles, keys, etc found in some ovens help to confirm that)