The Umatilla Chemical Depot opened in 1941, to prepare for World War II. The depot's mission was to store and maintain a variety of military items, from blankets to ammunition. The depot took on its chemical weapons storage mission in 1962 and stored 12% of the nation's stockpile. From 1990 to 1994 the facility reorganized in preparation for eventual closure, shipping all conventional ammunition and supplies to other installations.