Manhattan Project History

In early October 1942, Gen. Leslie Groves, the commander of the Manhattan District of the Corps of Engineers, learned from scientists in the Office of Scientific Research and Development (OSRD) that they needed a new laboratory to concentrate their scattered theoretical and experimental efforts to design a nuclear weapon.

Groves began a search throughout the West. The Manhattan District finally found a suitable site in New Mexico, but it was not Los Alamos.

In an Oct. 8 meeting with J. Robert Oppenheimer, Groves heard of the proposal for a central laboratory, which OSRD scientists had endorsed. After a second meeting a week later, with Oppenheimer and Col. J.C. Marshall on a Chicago-New York train, he invited Oppenheimer; Arthur Compton, his superior in the OSRD hierarchy; and OSRD Director Vannevar Bush to a meeting Oct. 19, when a formal decision was to be made to establish the Laboratory.

They initially thought of placing the laboratory at Oak Ridge, Tenn., because most of the plants to make 235-uranium were planned for a site Groves had just acquired there - or in Chicago, where Compton's Metallurgical Laboratory was located.

But Groves believed that the project required a more remote site. It would need a climate that permitted year-round construction, safety from enemy attack, transportation and access to power, water and fuel.

It would also have to provide an adequate testing ground and, for reasons of safety and security, should be in a sparsely populated area. Despite this last requirement, Groves also hoped that it would have sufficient buildings to house a small research staff.

After considering a site near Los Angeles, which he rejected on security grounds, and one near Reno, Nev., which he found unsuitable because of winter snows, Groves told Maj. John Dudley of the Manhattan District staff to survey the West for potential sites.

Dudley, borrowed from another district of the corps of engineers, was not supposed to know the purpose of the installation whose site he was looking for. However, after a short talk with Oppenheimer, Edwin McMillan and the other scientists planning the new laboratory, Dudley said, "[I] knew what they were doing quite thoroughly. I tried to turn them off, but within two minutes they would again be leaking information."

What Dudley needed to know was how large the laboratory would be.

"Based on Oppenheimer's idea that six scientists, assisted by some engineers, technicians and draftsmen, could do the job quite rapidly and effectively," and adding support personnel, Dudley first estimated 265 would need to be accommodated.

After talking to Ernest Lawrence and Oppenheimer in Berkeley, he raised this number to 450 and, by the end of November, to 600. This determined the water supply, housing and other resources that the new site would require.

Elaborating on his criteria, Groves specified that the site had to be at least 200 miles from any ocean or any international boundary and that sufficient housing already be in place so that the six scientists could move in and start the think-tank immediately.

Groves also wanted a natural bowl ringed by hills that could help secure the site and contain any accidental explosions.

"Toward the end of October 1942, I started out on my search," Dudley later recalled. "My plan was to visit the various Corps of Engineers offices in the Southwest.

"I carried with me a letter from the chief of engineers that said 'give this man all the help he needs.' . . . I traveled by air, rail and auto. Perhaps a thousand miles were covered on two-lane roads - one lane for the left wheels and one lane for the right wheels. When the going got tough, I switched to a jeep, and when it got even tougher, I rode a horse."

Dudley searched parts of California, Nevada, Utah, Arizona and New Mexico. His first choice for the laboratory site was Oak City, Utah. "It was a delightful little oasis in south central Utah. The railroad was only 16 miles away over a nice, easy road. The airport was not too distant. The water supply was good. It was surrounded by hills, and beyond there was mostly desert. However, I noticed one thing: If we took over this area we would evict several dozen families and we would also take a large amount of farm acreage out of production."

Based on these impediments, Dudley recommended his second choice, the little town of Jemez Springs, N.M.

The hot springs there had attracted a resort hotel, and there were a number of empty buildings but very few people who would have to be evicted. It was surrounded by mountains and a small ridge would separate the technical area from the residential area.

"If the place blew up, only the six scientists would be involved and not all the families," Dudley recalled. The access road was adequate to haul the scientific equipment that Oppenheimer, fellow scientist John Manley and McMillan wanted for the new laboratory.

Dudley's immediate superior, Marshall, approved the area for a site study, which was conducted by members of the Albuquerque Office of the Corps of Engineers. Oppenheimer and the OSRD scientists, however, needed to approve the site. If they did, the new Laboratory would be located on the western slopes of the Jemez Mountains of New Mexico.

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