M/T Igloo Moon; Key Biscayne, Florida

Key Biscayne, Florida | 1996-Nov-06

Initial Notification: The M/T Igloo Moon, a liquid propane gas (LPG) tank vessel carrying a full cargo (6,589 metric tons) of butadiene to Houston, Texas, ran aground November 6, 1996, on a sand bottom, in 25 feet of water, within the Biscayne National Park boundary. The vessel was reportedly carrying 57,000 gallons of IFO 380, a heavy fuel oil similar to #6; 30,000 gallons of marine diesel; and 6,000 gallons of lube oil. The USCG immediately began its incident command and by early that morning established a Unified Command at MSO Miami. A primary concern was the stability of the butadiene cargo and potential for evacuations. Butadiene is a colorless gas with a mild gasoline-like odor. It is flammable, reactive, and mildly toxic by inhalation, causing eye and respiratory tract irritation at high concentrations. Butadiene is a suspected human carcinogen. It was shipped as a liquefied compressed gas under refrigeration. Chemical inhibitor was added to it to prevent polymerization. USCG district 7. Keyword: endangered species.