The Chernobyl nuclear reactor disaster was the third biggest news story in the United States in 1986.
The Mighty Oak nuclear test accident in Nevada didn’t make any list of stories which made news in 1986.
At the same time that the U.S. government and the media were criticizing the Soviet Union for its cover-up of the Chernobyl tragedy, the U.S. was trying to conceal a nuclear accident of its own.
On April 10, 1986, an underground weapons effects test, codeÂnamed Mighty Oak, got out of control.
It left dangerous levels of radiation in the underground test tunnel and possibly destroyed some $20 million worth of test equipment.
During the next month, the Department of Energy (DOE) began releasing radioactive gases from the accident into the atmosphere.
Initially, the DOE announced that the test had been “routine” and repeatedly told reporters (who had heard of the mishap) that there had been “no problem” with the test. On May 1, the DOE finally admitted that the tunnel containment system of blast doors and seals had failed and the tunnel had been contaminated. The venting of radioactive gases was not admitted until May 7.
While the full story is still not known, it appears that some $20 million of test equipment may have been destroyed in the accident and that the levels of radioactive inert gas, Xenon 133, fifty miles from the test site, were up to 550 picocuries per cubic meter. These levels are within official safety guidelines but were several times higher than the well-publicized highest levels of air-born radioactivity from Chernobyl reported inside the United States. This also was the highest recorded figure from a test since the “Baneberry” accident of 1970 when 6.7 million curies of radioactivity escaped from a test malfunction.
Nuclear testing critic Dr. Rosalie Bertell, director of research for the International Institute of Concern for Public Health, charges that the cover-up is still continuing and that the real radiation hazards from Mighty Oak are not yet known.
 SOURCE:
THE THREEPENNY REVIEW (PACIFIC NEWS SERVICE), Fall 1986, “The Nevada Radiation Cover-Up,” by Peter Dale Scott, p 3.