Major General Eugene Reybold of the U.S. Army Corps of Engineers authorizes the construction of facilities that would house the "Development of Substitute Materials" project, better known as the Manhattan Project.

Eugene Reybold was distinguished as the World War II Chief of Engineers who directed the largest United States Army Corps of Engineers in the nation's history.

The United States Army Corps of Engineers (USACE) is the military engineering branch of the United States Army. A direct reporting unit (DRU), it has three primary mission areas: Engineer Regiment, military construction, and civil works. USACE has 37,000 civilian and military personnel, making it one of the world's largest public engineering, design, and construction management agencies. The USACE workforce is approximately 97% civilian, 3% active duty military. The civilian workforce is mainly located in the United States, Europe and in select Middle East office locations. Civilians do not function as active duty military and are not required to be in active war and combat zones; however, volunteer opportunities do exist for civilians to do so.

The Manhattan Project was a research and development program undertaken during World War II to produce the first nuclear weapons. It was led by the United States in collaboration with the United Kingdom and Canada.