Originally, POMCUS sites were primarily simply guarded, fenced-in lots of pre-loaded, maintained vehicles and weapons systems ready to roll, although the precursor to POMCUS sites was a series of underground storage areas liberated from the Germans in Pirmasens and the outlying areas Husterhoeh Kaserne utilized to store combat-readied armor.
In addition to the USAMMA headquarters located at Fort Detrick, USAMMA has operational maintenance and storage locations in Camp Carroll, South Korea; Sagami General Depot, Japan; Defense Depot Tracy, California; Sierra Army Depot, California; Defense Depot Hill, Utah; Tobyhanna Army Depot, Pennsylvania; Naval Weapons Station Charleston, South Carolina; Husterhoeh Kaserne, Pirmasens, Germany; As Saliyah Army Base, Qatar; and Camp Arifjan, Kuwait.