Nuclear Health and Safety:

Examples of Post World War II Radiation Releases at U.S. Nuclear Sites

RCED-94-51FS: Published: Nov 24, 1993. Publicly Released: Dec 16, 1993.

Additional Materials:


Office of Public Affairs
(202) 512-4800

Pursuant to a congressional request, GAO provided information on planned post-World War II radioactive releases at U.S. nuclear sites, focusing on: (1) the Green Run test conducted at the Hanford, Washington, site in December 1949; and (2) several other tests at U.S. nuclear sites in the late 1940s and early 1950s that involved radioactive releases.

GAO found that: (1) the Green Run test was an atmospheric radioactivity monitoring experiment designed to detect evidence of far away nuclear materials; (2) the Green Run test released a total of almost 28,000 curies of radioactive material; (3) some of the nuclear plant's safety procedures were intentionally relaxed, resulting in a larger than normal radioactive release; (4) the Green Run test was not unsafe at the time but, according to the Atomic Energy Commission (AEC), the Hanford release exceeded existing local limits for deposition in vegetation and animal tissue, and would not have been permissible under today's more stringent safety standards for U.S. nuclear sites; (5) a study of historical Hanford radiation doses is currently under way; (6) 12 other planned radioactive releases occurred at three U.S. nuclear sites from 1948 to 1952; (7) AEC conducted radiation warfare tests at its sites in Oak Ridge, Tennessee, and Dugway, Utah, to develop an air-dropped radioactive munition; (8) AEC conducted atmospheric radiation-tracking tests at its site in Los Alamos, New Mexico, to analyze the diffusion of radioactive gases and fallout effects; and (9) two of the Los Alamos tests resulted in the detection of atmospheric radiation over populated areas, but there was no documentation of potential health effects from these tests.

Nov 19, 2020

Oct 29, 2020

Oct 15, 2020

Jul 24, 2020

Jun 24, 2020

Jun 9, 2020

May 13, 2020

May 12, 2020

Apr 29, 2020

  • energy icon, source: Art Explosion

    Priority Open Recommendations:

    Department of Energy
    GAO-20-285PR: Published: Apr 22, 2020. Publicly Released: Apr 29, 2020.

Apr 17, 2020

Looking for more? Browse all our products here