120718-N-AC887-011 PACIFIC OCEAN (JULY 18, 2012) Chief of Naval Operations (CNO) Adm. Jonathan Greenert, left, and Secretary of the Navy (SECNAV) the Honorable Ray Mabus observe as the Military Sealift Command fleet replenishment oiler USNS Henry J. Kaiser (T-AO 187), background, transfers biofuels to the guided-missile cruiser USS Princeton (CG 59) during a replenishment at sea. The fueling is part of the U.S. Navy's Great Green Fleet demonstration portion of the Rim of the Pacific (RIMPAC) 2012 exercise. (U.S. Navy photo by Chief Mass Communication Specialist Sam Shavers/Released)