A molten metal scrap submergence system comprising a furnace and a vortexing scrap submergence well. The vortexing scrap submergence well includes a diverter suspended above the well and oriented for immersion in a bath of molten metal circulating within the well. The system, or an alternative scrap submergence system, can include a hood element disposed in an overlapping position with regard to a top opening of the scrap submergence well. The hood at least substantially seals the top opening. The hood element includes a scrap piece feed chute and a burner allowing carbon containing vapor evaporated from the surface of the molten scrap pieces to combust and form predominantly water. The system, or an alternative scrap submergence system can include internal side walls of the well with a first diameter portion adjacent and above said ramp and a second, larger diameter portion above said first portion.