“ORE CARRIER HEADS INTO LAKE SUPERIOR FROM DULUTH HARBOR AHEAD IS A LAYER OF SMOG HANGING IN THE AIR OVER THE CITIES OF DULUTH MINNESOTA AND SUPERIOR, WISCONSIN, SMOKE FROM ORE BOAT STACKS CONTRIBUTE TO SMOG,” Series: DOCUMERICA: The Environmental Protection Agency’s Program to Photographically Document Subjects of Environmental Concern, 1972 – 1977, Record Group 412: Records of the Environmental Protection Agency, 1944 – 2006, U.S> National Archives.
Rights clearance resides with the user.