han 4
roentgens; another 22 individuals received between 4 and 15 roentgens.

PREFACE

From 1945 to 1962, the U.S. Government, through the Manhattan Engineer
District (MED) and its successor agency, the Atomic Energy Commission
(AEC), conducted 235 tests of nuclear devices at sites in the United
States and in the Atlantic and Pacific Oceans. In all, an estimated
220,000 Department of Defense (DOD)* participants, both military and
civilian, were present at the tests. Project TRINITY, the war-time
effort to test-fire a nuclear explosive device, was the first
atmospheric nuclear weapons test.

* The MED, which was part of the Army Corps of Engineers, administered
the U.S. nuclear testing program until the AEC came into existence in
1946. Before DOD was established in 1947, the Army Corps of Engineers
was under the War Department.

In 1977, 15 years after the last above-ground nuclear weapons test,
the Centers for Disease Control** noted a possible leukemia cluster
among a small group of soldiers present at Shot SMOKY, a test of
Operation PLUMBBOB, the series of atmospheric nuclear weapons tests
conducted in 1957. Since that initial report by the Centers for
Disease Control, the Veterans Administration 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
weapons testing program.

** The Centers for Disease Control are part of the U.S. Department of
Health and Human Services (formerly the U.S. Department of Health,
Education, and Welfare).

In late 1977, DOD began a study to provide data to both the Centers
for Disease Control and the Veterans Administration on potential
exposures to ionizing radiation among the military and civilian
participants in atmospheric nuclear weapons testing. DOD organized an
effort to:

o Identify DOD personnel who had taken part in the atmospheric nuclear
weapons tests

o Determine the extent of the participants' exposure to ionizing
radiation

o Provide public disclosure of information concerning participation by
military personnel in Project TRINITY.

METHODS AND SOURCES USED TO PREPARE THIS VOLUME

This report on Project TRINITY is based on historical and technical
documents associated with the detonation of the first nuclear device
on 16 July 1945. The Department of Defense compiled information for
this volume from documents that record the scient