Waste Management

The mounds around the furnace are heaps of slag, the waste product left after iron ore was superheated so molten iron sank to the bottom while impurities and limestone residue rose to the surface and were skimmed off and discarded. Once hardened, this material became slag, which could look like volcanic glass or lava rock. Slag was removed from the furnace about every six hours, and the amount produced became such a problem that it was used to fill holes and surface roads throughout the village. Eventually, more slag was produced than could be used, so it was piled in heaps near the furnace, and some of the forest floor visible today may lie atop old slag mounds.

Maryland · United States