E. Frank Miller was working at DuPont’s Belle Works in August 1943 when he was recruited to the TNX segment of DuPont working on the Manhattan Project by Dr. Monte Evans, his former manager. Miller was one of three Construction Consultants reporting to C. N. Gross at Hanford. When he arrived at Hanford in 1944, Miller was responsible for graphite fabrication and quality control.
After the completion of the 105-B reactor he served as Construction Consultant for the 105-D and 105-F reactors, as well as the chemical separation facilities at the T-Plant area. Miller was appointed Assistant Chief Supervisor of the 100-F area after the completion of the 105-F reactor and continued to work for DuPont through September 1946. Afterwards he joined the USAEC (United States Atomic Energy Commission) in Washington, D.C. and supervised the production of fissionable material through the mid-1960s.