[urban caveman]

claytonx have you ever known of a filter system of some kind for water that is draining freely from a mine through an adit or similar? the entrance i was in had water flowing out of it which went through some kind of filter system before entering a near by brook. it was a big metal box so to speak with the water entering at the top and draining around half way down. the water draining from the entrance was orange from iron discolouration but clear when it left the filter. if not a mine has anyone any other ideas what it could possibly be? thanks