Special Engineer Detachment

9812nd Special Engineer Detachment
Manhattan Project Shoulder Patch
Active	22 May 1943–15 August 1947
Country	United States
Branch	United States Army Corps of Engineers
Size	6,032 on 1 December 1945
Garrison/HQ	Los Alamos Laboratory, Oak Ridge
Engagements	World War II Manhattan Project

The Special Engineer Detachment (SED) was a U.S. Army program that identified enlisted personnel with technical skills, such as machining, or who had some science education beyond high school, to meet the needs of the Manhattan Project during World War II. SED personnel Clinton Engineer Works, Hanford Engineer Works and Los Alamos Laboratory. SED personnel began arriving at Los Alamos in October 1943, and by August 1945, 1,800 worked there. They worked in all areas and activities of the Laboratory, including the Trinity Test, and were also involved in overseas operations on Tinian in support of the atomic bombing of Hiroshima and Nagasaki and the Operation Crossroads nuclear test series at Bikini Atoll in 1946.

Authorization and recruitment

With mobilization of American manpower underway due to the needs of the armed forces, the leadership of the Manhattan Project anticipated that they would have difficulty recruiting and retaining skilled technical staff. ^[1] The meet this need, the Special Engineer Detachment was formed by the Army Service Forces on 22 May 1943, initially with an authorized strength of 334 enlisted men. ^[2]

To meet the Manhattan Project's needs for personnel with technical skills, the Manhattan Project's Personnel Division was assisted by the headquarters of the Army Specialized Training Program (ASTP)], which placed its resources at the Manhattan Project's disposal. The ASTP arranged with the universities for security clearances and interviews with ASTP students. The Office of the National Roster of Scientific and Specialized Personnel looked through its files, which contained entires for 597,666 men and women by 1 July 1943, and provided the names, industrial and educational background and military draft status of qualified scientific personnel. Many colleges and universities furnished the names and draft status of ^{[3] [4]}

Personnel authorizations were handled by the United States Army Corps of Engineers, of which the Manhattan District was a part, until 31 July 1945, when responsibility passed to the headquarters of Army Service Forces. ^[5] In January 1945, the Corps of Engineers activated the 9812th Technical Service Unit, and most of the enlisted personnel at the Clinton Engineer Works, Hanford Engineer Works and Los Alamos Laboratory were transferred to the new unit on 1 February. At Los Alamos, however, the Military Police Corps, Women's Army Corps and service personnel remained part of the 8th Service Command's 4817th Service Command Unit. ^[6]

The demands of the Manhattan Project for specialized skills grew rapidly, and there was a series of increasing authorizations until 31 October 1945, when a peak strength of 6,032 was authorized. During 1946, this was decreased as the demobilization of United States armed forces after World War II progressed, and the authorization was lowered to 2,203 on 9 December 1946. ^[2] The Manhattan Project reached peak strength of 4,976 enlisted personnel on 1 November 1945, but this also included Military Police Corps, Women's Army Corps and service personnel as well as scientific and technical staff. ^[2] Recruitment continued into 1946, with 1,449 additional personnel requested during the year to replace demobilized personnel, and the Manhattan Project still has 2,326 enlisted personnel on 31 December 1946. ^[2] The Manhattan District was abolished on 15 August 1947. ^[7]

Legacy

An article released by the Atomic Heritage Foundation wrote that: "After the war, many went back to school and became successful scientists in their own right—including Val Fitch, who was awarded a Nobel Prize in Physics in 1980." ^{[8] [9] [10] [11] [12] [13]}

References

1. Jones 1985, p. 358.
2. Manhattan_District 1947b, pp. 7.3–7.4.
3. Manhattan_District 1947b, pp. 7.4–7.5.
4. Carmichael 1944, pp. 141–147.
5. Manhattan_District 1947b, pp. S12–S13.
6. Jones 1985, p. 361.
7. Manhattan_District 1947a, p. F2.
8. "Special Engineer Detachment". Nuclear Museum. Retrieved 29 November 2025.
9. "Special Engineer Detachment" (PDF). Department of Energy. Archived from the original (PDF) on 20 October 2020.
10. "Manhattan Project: People > Military Organizations > Special Engineering Detachment (SED)". Department of Energy. Retrieved 6 December 2025.
11. "Engineers behind the Manhattan Project". Los Alamos National Laboratory. Retrieved 6 December 2025.
12. Richardson, Darrell (28 December 2010). "Special Engineer Detachment remembered, reassembled". Oak Ridger. Retrieved 6 December 2025.
13. Adamson, June (Fall 1997). "The SED in Oak Ridge, 1943-1946: Using a Secret Newsletter by a secret army detachment to learn more about a secret city in Tennessee". Tennessee Historical Quarterly. 56 (3): 196–211. JSTOR   42627362.

Sources

• Bederson, Benjamin (2004). "SEDs at Los Alamos". In Kelly, Cynthia C. (ed.). Remembering the Manhattan Project: a Personal Memoir. Singapore: World Scientific Publishing. pp. 81–88. ISBN   978-981-256-040-7. OCLC   5011510150.
• Bederson, Benjamin (2001). "SEDs at Los Alamos: A Personal Memoir" (PDF). Physics in Perspective . 3 (1). Basel: Birkhäuser Verlag: 52–75. Bibcode:2001PhP.....3...52B. doi:10.1007/s000160050056. S2CID   117157405 . Retrieved 7 December 2025.

• Carmichael, Leonard (February 1944). "The National Roster of Scientific and Specialized Personnel". The Scientific Monthly. 58 (2): 141–147. JSTOR   18092.

• Jones, Vincent (1985). Manhattan: The Army and the Atomic Bomb (PDF). United States Army in World War II. Washington, D.C.: United States Army Center of Military History. OCLC   10913875 . Retrieved 30 September 2025.

• Manhattan District (1947a). General (PDF). Manhattan District History, Book I – General. Vol. 1. Washington, D.C.: Manhattan District. Retrieved 7 December 2025.
• Manhattan District (1947b). Personnel (PDF). Manhattan District History, Book I – General. Vol. 8. Washington, D.C.: Manhattan District. Retrieved 7 December 2025.
• Manhattan District (1947c). Technical (PDF). Manhattan District History, Book VIII – Los Alamos Project (Y). Vol. 28. Washington, D.C.: Manhattan District. Retrieved 7 December 2025.

External links

• "Herbert M. Lehr Collection (Special Engineering Detachment 1943–1946)". Veterans History Project. Library of Congress. 6 November 2019. AFC/2001/001/12058.