Sergeant Major Rivera enlisted in the Marine Corps in July 2000, and attended recruit training at MCRD, Parris Island, South Carolina 2nd Battalion, Fox Company. After Recruit Training, he completed Marine Combat Training, where he received orders to Ft. Leonard Wood, Missouri for MOS School as a Motor Transport and Logistic Vehicle System Operator. Upon completion of MOS school, Private First Class Rivera received orders to 2d Transportation Support Battalion, 2d Force Service Support Group, Bravo Company, Camp LeJeune, North Carolina.
In March 2002 Lance Corporal Rivera deployed to Zaragoza, Spain in support of Dynamic Mix. In January 2003, Corporal Rivera deployed to Kuwait and subsequently to Iraq in support of Operation Iraqi Freedom I. In August 2004, he returned to Iraq in support of Operation Iraqi Freedom II-2, and participated in operations across Al-Anbar Province, including Operation Phantom Fury. He was promoted to Sergeant on October 2004 and received orders on February 2005 to Combat Service Support Group-3 in Kaneohe Bay, Hawaii.
Sergeant Rivera was attached to 1st Battalion, 3d Marines and deployed, December 2005, to Afghanistan in support of Operation Enduring Freedom 6/7, Operation Mountain Lion, Korengal Valley, Kunar Province. Upon completion of the deployment, he returned to Combat Service Support Group-3.
Sergeant Rivera was later assigned to a developmental team called Wolf Pack, helping develop the future capabilities of the United States Marine Corps. He was selected as Non-Commissioned Officer of the Year for III MEF in 2007. At this time, he requested assignment to Drill Instructor School and later attended in January 2008.
Sergeant Rivera was promoted to Staff Sergeant on April 2008 and served as a Drill Instructor, Senior Drill Instructor, and Chief Drill Instructor with Company L and Company M, Third Recruit Training Battalion, Marine Corps Recruit Depot, Parris Island. He was selected to become an Instructor at Drill Instructor School, where he was meritoriously promoted to the rank of Gunnery Sergeant, on January 2011.
After completing a successful tour as a Drill Instructor, Gunnery Sergeant Rivera was assigned to Truck Company Bravo, Headquarters Battalion, 1st Marine Division and served as Company Gunnery Sergeant and Company First Sergeant. He then attached to 2d Battalion, 7th Marines where he was forward deployed, September 2012, as the Motor Transport Chief in Sangin, Helmand Province, Afghanistan. Upon return from deployment, he attended the Advanced Course in Camp Pendleton, California and graduated as the Honor Graduate and “Gung Ho” recipient for the course.
In July 2014, Gunnery Sergeant Rivera executed orders to 1st Battalion, 12th Marines, Headquarters' Battery in Marine Corps Base Kaneohe Bay, Hawaii. He was selected to the rank of First Sergeant and executed orders to 1st Battalion, 3d Marines. First Sergeant Rivera deployed with Company C in support of the Unit Deployment Program which included exercises in Japan and South Korea. Upon redeployment First Sergeant Rivera was moved to be Weapons Company before receiving orders to Officer Candidates School in Quantico, Virginia.
In May 2017, First Sergeant Rivera was assigned to the Headquarters and Service Company, Company C, and Company L. Sergeant Major Rivera was promoted to his current rank in November 2019 and was assigned to 1st Battalion, 3d Marine Regiment, now re-designated as the 3d Littoral Combat Team, 3d Marine Littoral Regiment, in which he currently serves today.
Sergeant Major Rivera's personal awards include the Navy and Marine Corps Commendation Medal with one silver star, two gold stars, and a combat distinguishing device, in Lieu of 8th award, Navy and Marine Corps Achievement Medal with two gold stars in lieu of 3rd award and the Combat Action Ribbon with a gold star in lieu of 2nd award.