An explosion onboard the EMC423 tank barge on the Chicago Sanitary and Ship Canal Wednesday evening has resulted in the presumed death of a crewmember and the closure of the waterway, the U.S. Coast Guard reported. The tank barge that exploded was carrying approximately 588 thousand gallons of Clarified Slurry Oil. This cargo is a byproduct of the oil refining process and is used to make fuel oils. It was loaded onto the barge at the Exxon Mobile Plant in Joilet, Ill., and was destined for the Ameropan Oil Corporation facility in Cicero, IL. The tank barge involved in the explosion is owned and operated by the Egan Marine Corporation. Egan Marine operates a small fleet of barges and towboats in Lemont, Ill.