Sergeant Major Orellano enlisted in the Marine Corps on 9 May 1988 and attended recruit training at Marine Corps Recruit Depot, San Diego, California. Following the completion of recruit training he was sent to NAS Millington, Tennessee with follow on training to MCAS, Camp Pendleton and MCAS, Cherry Point, NC for in his Military Occupational Specialty, (6531), Aviation Ordnance. Upon completion of all schools he was assigned to his first unit, Marine Observation Squadron One (VMO-1) MCAS, New River, NC. During his time there he conducted multiple deployments in support of the Drug Interdiction enforcement in Miami and the Caribbean, numerous Weapons and Tactics Instructor Training (WTI), MCAS Yuma, Az and Combined Arms Exercises (CAX) MCB, 29 Palms, California. In December 1991, he deployed in support of Operation Desert Storm/Shield.
In August 1992, he reenlisted and applied for the Marine Security Guard (MSG) Program. He attended MSG school Class 1-93 and graduated in November 1992. Sergeant Orellano first post as a Watch Stander was MSG detachment, American Embassy, Montevideo, Uruguay. His second and third posts were MSG detachments at the American Embassies Yaounde, Cameroon and Tokyo, Japan.
In January 1996, he returned to CONUS and was assigned to HMT-303 MAG-39, where he served in the billet of Ordnance Supervisor. In July of 1997, Staff Sergeant Orellano was reassigned to HMLA 369 MAG-39. During this time he completed two Unit Deployments to Okinawa, Japan serving in the billets ordnance Supervisor and Quality Assurance Representative.
In February 2001, he reapplied for the MSG Program and attended Class 3-2001 as a student Detachment Commander. Upon completion he was assigned to his first post as the Detachment Commander, MSG detachment, American Embassy, Bamako, Mali, West Africa. His second post was MSG detachment, American Embassy, Mexico City, Mexico and his third post was the United States Tri-Missions to Brussels, Belgium.
In April 2004 he returned to the Fleet Marine Force and was assigned to 2d Battalion, 1st Marine Regiment. He served as the First Sergeant for Fox Company and Headquarters and Service Company. During this time he deployed in support of Operation Iraqi Freedom 4-6 (OEF 4-6) in the Al Anbar Province and conducted a year long UDP in Okinawa in support of the 31st Marine Expeditionary Unit.
In Mar 2008, he was transferred to the School of Infantry West, Camp Pendleton, California. Assigned as a First Sergeant to Marine Combat Training Battalion, he activated the newly formed Kilo Company. In January of 2009, he was reassigned within the School of Infantry to activate the newly formed Combat Instructor School.
In February 2010, First Sergeant Orellano was transferred to 2d Battalion, 6th Marine Regiment and assumed the duties of the First Sergeant, Headquarters and Service Company. During this time he deployed in support of Operation Enduring Freedom 10-2, conducting and supporting combat operations in Marjah, Helmand Province, Afghanistan.
Sergeant Major Orellano was promoted to his present rank on 1 Feb 2011 and assumed his current duties on 01 May 2012.
His personal awards include the Meritorious Service Medal, Navy and Marine Corps Commendation Medal (3rd Award) Navy and Marine Corps Achievement Medal (2nd Award) and the Combat Action Ribbon.