November 24, 1993



The Honorable John Glenn

Chairman, Committee on

Governmental Affairs

United States Senate



Dear Mr. Chairman:

In response to your request, this fact sheet provides information

on several - planned radioactive releases that were conducted at

U.S. nuclear sites in the post World War II years, including a

release at Hanford, Washington, in December 1949. The Hanford

event, referred to as the Green Run test, has been the subject of

public attention in the Pacific Northwest since the late 1980s.

Public concern has been heightened by the longtime secrecy

surrounding the event and the fact that some test details still

remain classified. As agreed with your office, we are presenting

information on (1) the Green Run test and (2) several other tests

at U.S. sites in the late-1940s and early 1950s that involved

radioactive releases.

In summary, the Green Run test was atmospheric radioactivity

monitoring experiment conducted by the military and the former

Atomic Energy Commission (AEC). A premise of the test was that

aerial monitoring and sampling of a radioactive cloud, even far

from the source, could give evidence of nuclear materials.

Conducted on December 2-3, 1949, the test released a recorded total

of almost 28,000 curies of radioactive material from a special

agent fuel reprocessing operation into the atmosphere over

southeast Washington and Oregon.

For the test, some of the plant's usual radiation safety

procedures were intentionally relaxed, resulting in a larger than

normal radioactive release. Test participants did not consider the

test to be unsafe at the time, and the radiation doses that the

off-site populace might have received as a result of the test were

not estimated at the time (based on the historical test

documentation available to us). However, according to the AEC, in

some locations, the release exceeded then-existing local Hanford

limits for deposition in vegetation and animal tissue, and it may

not have been permissible under today's more stringent safety

standards for U.S. nuclear sites. Presently, to better understand

the health effects of the test. Please call me at (202) 512-3841

if you or your staff have anyquestions. Major contributors to this

fact sheet are listed in appendix II.

Sincerely yours,

Victor S. Rezendes

Director, Energy and Science Issues

___________

An identically titled classified version of this fact sheet (C-

GAO/RCED-93-IFS) was issued to you on June 30, 1993.

/2/A curie is a basic unit of radioactivity that is equal to 3.7x10

exponential 10 radioactive disintegrations per second