Herdel’s first assignment was to Explosive Ordnance Disposal Mobile Unit (EODMU) 2 in Virginia Beach, Virginia from December 1990 to August 1993. He attended Basic EOD Technician School in Indian Head, Maryland and, upon graduation, was assigned to EODMU 5 in Agana, Guam from September 1994 to December 1997. While there he served on the first Command Special Operations Detachment.
From January 1998 to December 1999, Herdel was assigned to EODMU 2, Det. Roosevelt Roads, Puerto Rico, where he conducted operations throughout the Caribbean and South American areas of operation. Following this, he transferred to EODMU 2 on board Naval
Amphibious Base Little Creek in February 2000, making multiple deployments while assigned to the 22 MEU and on Seal Team 8, Alpha and Charlie Platoons.
In September 2003, Herdel transferred to Explosive Ordnance Disposal Training and Evaluation Unit 2, Ft. Story, Virginia, where he was assigned as the air operations department head from June 2004 to May 2006. His next assignment took him to the U.S. Army Military Freefall School in Yuma, Arizona. He was the first EOD Technician to be permanently stationed at the school and was awarded Freefall Instructor number 578. He returned to EODMU 2 in December 2007 to deploy as the leading chief petty officer (LCPO) of multiple platoons in support of Operation Iraqi Freedom and CENTCOM operations, and was also advanced to Master Chief Petty Officer.
Herdel was assigned as operations department LCPO at EODMU 6 in Virginia Beach, Virginia and deployed as the operations master chief for Commander, Task Group (CTG) 56.1. Upon his selection as a command master chief (CMC) in 2012, he was transferred to EODMU 2.
As CMC of EODMU 2, he deployed as part of the leadership team in support of CTG 56.1. It was during this time that the command was awarded the first Navy Expeditionary Combat Command (NECC) Battle (Navy) "E" commendation. In July 2015 he was selected as the first command master chief of Expeditionary Warfighting Development Center.
In October 2016, Herdel was selected to be the NECC Force Master Chief, where he currently serves.
Herdel holds a Bachelor’s Degree in Business Management and has completed the following courses: Joint Special Operations University Summit Course, National Defense University Keystone Course, Naval Postgraduate School Senior Leader Seminar, Georgetown University Capitol Hill Workshop, Daniel K. Inouye Asia-Pacific Center for Security Studies Asia Pacific Orientation Study, Executive Leadership Symposium, Naval War College Senior Enlisted Academy and Command Leadership School. Herdel is a qualified Master Explosive Ordnance Disposal Technician and Free-Fall Naval Parachutist. His personal decorations include the Bronze Star Medal, Meritorious Service Medal (2), Navy and Marine Corps Commendation Medal (5), Navy and Marine Corps Achievement Medal (9), and Army Achievement Medal.