MEMPHIS - The Coast Guard Cutter Scioto, a 65-foot river buoy tender homeported in Keokuk, Iowa, undergoes drydock to replace its Caterpillar 353 main diesel engines with twin V-12 diesel engines made in Italy, June 20, 2011. The Scioto is scheduled to resume operations on the Mississippi River in late September. U.S. Coast Guard photo by Master Chief Petty Officer Michael Ellis.