in Tennessee.

The Oak Ridge site was selected on the basis of several criteria. The plutonium pilot facilities needed to be 2 to 4 mi from the site boundary and any other installation, in case radioactive fission products escaped. While security and safety concerns suggested a remote site, it still needed to be near sources of labor, and accessible by road and rail transportation. A mild climate that allowed construction to proceed throughout the year was desirable. Terrain separated by ridges