LAKE MICHIGAN - The U.S. Environmental Protection Agency research vessel Lake Guardian transits through Lake Michigan near Chicago with a U.S. Coast Guard Vessel of Opportunity Skimming System attached to the ship during an exercise May 9, 2012. The VOSS is intended for oil spill response, can be used on various types of vessels, and was last used during the Deepwater Horizon response in the Gulf of Mexico. (U.S. Coast Guard photo by Petty Officer 1st Class Lauren Jorgensen)