Y-12 National Security Complex
National Nuclear Security Administration (operated by Consolidated Nuclear Security), Oak Ridge, Tennessee
Y-12 in Oak Ridge, Tennessee broke ground in February 1943 as the Manhattan Project's electromagnetic uranium separation plant and employed more than 22,000 people by 1945. During the Cold War it produced nuclear weapon secondaries. It remains an NNSA site that manufactures, processes and stores special nuclear materials.
- Company
- National Nuclear Security Administration (operated by Consolidated Nuclear Security)
- Status
- Operating
- Opened
- 1943
- Employees
- Not stated
- Industry
- Aerospace and defense
- Revised
- November 12, 2026
What is made here
Manufactures, processes and stores special nuclear materials for national security; built in WWII to enrich uranium for the atomic bomb.
Facts
| Groundbreaking | Ground was broken on February 18, 1943 for the first production building of the Y-12 Electromagnetic Separation Plant (federal: y12.doe.gov) |
|---|---|
| Original mission | Built to make enough enriched uranium for a new kind of bomb during the Manhattan Project (federal: y12.doe.gov) |
| Peak workforce | More than 22,000 workers were employed at the site at its 1945 peak (federal: y12.doe.gov) |
| Cold War | About 8,000 people worked around the clock producing nuclear weapon secondaries during the Cold War (federal: y12.doe.gov) |
| Mission today | A national asset for manufacturing, processing and storing special materials vital to national security, and for preventing the spread of weapons of mass destruction (federal: y12.doe.gov) |
Figures are as stated by the source named next to each one. Company figures are the company's own claims.
Can you visit?
We haven't found a public tour of this factory. See factory tours in Tennessee.
Sources
- Y-12 National Security Complex: History (federal, checked November 12, 2026)
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