What responsibilities did Oak Ridge, Hanford, and Los Alamos have in the Manhattan Project?

The Manhattan Project utilized three primary sites, each with distinct responsibilities essential to the development of the first atomic weapons:

Oak Ridge, Tennessee

Originally known as the Clinton Engineer Works, Oak Ridge served as the primary site for the production of uranium-235. It housed large, complex facilities dedicated to isotope separation, utilizing electromagnetic and gaseous diffusion processes to enrich uranium. Additionally, it hosted an intermediate-scale reactor to support the development of plutonium production methods.12

Hanford, Washington

The Hanford Engineer Works was established as the project’s dedicated site for the large-scale production of plutonium-239. Its location on the Columbia River provided the necessary cooling water and hydroelectric power required for massive nuclear reactors. Once plutonium was synthesized from uranium, it was processed in chemical separation plants before being shipped to Los Alamos for weapon fabrication.13

Los Alamos, New Mexico

Los Alamos functioned as the project’s central scientific laboratory, often referred to as Project Y. Under the direction of J. Robert Oppenheimer, scientists and engineers were tasked with the design, development, and final manufacture of the atomic bomb. Their responsibilities included reducing fissionable materials from Oak Ridge and Hanford into pure metal, fabricating those materials into weapon components, and solving the complex engineering challenges required to create a deliverable, functional weapon.412