PREFACE Between 1945 and 1962, the U.S. Atomic Energy Commission (AEC) con- ducted 235 atmospheric nuclear weapon tests at sites in the United States and in the Pacific and Atlantic oceans. of Defense the tests. In all, about 220,000 Department (DOD) participants, both military and civilian, were present at Of these, approximately 142,000 participated in the Pacific test series and approximately another 4,000 in the single Atlantic test series. In 1977, 15 years after the last aboveground nuclear weapon test, the Center for Disease Control (CDC) of the U.S. Department of Health and Human Services noted more leukemia cases than would normally be expected among about 3,200 soldiers who had been present at shot SMOKY, a test of the 1957 PLUMBBOB Series. istration (VA) Since that initial report by the CDC, the Veterans Admin- has received a number of claims for medical benefits from former military personnel who believe their health may have been affected by their participation in the weapon testing program. In late 1977, the pOD began a study that provided data to both the cDpCc and the VA on potential exposures to ionizing radiation among the military and civilian personnel who participated in the atmospheric testing 15 to 30 years earlier. In early 1978, the DOD also organized a Nuclear Test Personnel Review (NTPR) tos @ Identify DOD personnel who had taken part in the atmospheric nuclear weapon tests @ Determine the extent of the participants' exposure to ionizing radiation @ Provide public disclosure of information concerning participation by DOD personnel in the atmospheric nuclear weapon tests.