Herbert Depke was born November 18, 1907 in Danville, Illinois. He received a B.S. from the University of Illinois in 1930, then began working for his family’s business. When the United States entered the Second World War, Depke began searching for war work. He began by working at a DuPont plant in Indiana, likely on conventional explosives. When the Dupont Company built the Manhattan Project plant in Hanford, WA, Depke volunteered to transfer to the new site.
Depke's son, Herbert W. Depke, gave an interview to the Atomic Heritage Foundation about life as a child at Hanford; you can hear it here.