PACIFIC OCEAN (May 22, 2021) Engineman 3rd Class Omar Valdivia inspects an oil sample aboard the Independence-variant littoral combat ship USS Omaha (LCS 12), May 22, 2021. Omaha is underway as part of the Essex Amphibious Ready Group (ARG) conducting integrated training with the 11th Marine Expeditionary Unit (MEU) off the coast of southern California. Together, the 11th MEU, Amphibious Squadron (PHIBRON) 1, and ships are designated as an ARG. (U.S. Navy photo by Ensign Alexandra Green)